patch-2.2.18 linux/drivers/usb/audio.c

• Lines: 3818
• Date: Thu Dec 7 15:01:03 2000
• Orig file: v2.2.17/drivers/usb/audio.c
• Orig date: Fri Apr 21 12:46:37 2000

diff -u --new-file --recursive --exclude-from /usr/src/exclude v2.2.17/drivers/usb/audio.c linux/drivers/usb/audio.c
@@ -1,126 +1,3741 @@
+/*****************************************************************************/
+
+/*
+ *	audio.c  --  USB Audio Class driver
+ *
+ *	Copyright (C) 1999, 2000
+ *	    Alan Cox (alan@lxorguk.ukuu.org.uk)
+ *	    Thomas Sailer (sailer@ife.ee.ethz.ch)
+ *
+ *	This program is free software; you can redistribute it and/or modify
+ *	it under the terms of the GNU General Public License as published by
+ *	the Free Software Foundation; either version 2 of the License, or
+ *	(at your option) any later version.
+ *
+ *
+ * 1999-09-07:  Alan Cox
+ *		Parsing Audio descriptor patch
+ * 1999-09-08:  Thomas Sailer
+ *		Added OSS compatible data io functions; both parts of the
+ *		driver remain to be glued together
+ * 1999-09-10:  Thomas Sailer
+ *		Beautified the driver. Added sample format conversions.
+ *		Still not properly glued with the parsing code.
+ *		The parsing code seems to have its problems btw,
+ *		Since it parses all available configs but doesn't
+ *		store which iface/altsetting belongs to which config.
+ * 1999-09-20:  Thomas Sailer
+ *		Threw out Alan's parsing code and implemented my own one.
+ *		You cannot reasonnably linearly parse audio descriptors,
+ *		especially the AudioClass descriptors have to be considered
+ *		pointer lists. Mixer parsing untested, due to lack of device.
+ *		First stab at synch pipe implementation, the Dallas USB DAC
+ *		wants to use an Asynch out pipe. usb_audio_state now basically
+ *		only contains lists of mixer and wave devices. We can therefore
+ *		now have multiple mixer/wave devices per USB device.
+ * 1999-10-28:  Thomas Sailer
+ *		Converted to URB API. Fixed a taskstate/wakeup semantics mistake
+ *		that made the driver consume all available CPU cycles.
+ *		Now runs stable on UHCI-Acher/Fliegl/Sailer.
+ * 1999-10-31:  Thomas Sailer
+ *		Audio can now be unloaded if it is not in use by any mixer
+ *		or dsp client (formerly you had to disconnect the audio devices
+ *		from the USB port)
+ *		Finally, about three months after ordering, my "Maxxtro SPK222"
+ *		speakers arrived, isn't disdata a great mail order company 8-)
+ *		Parse class specific endpoint descriptor of the audiostreaming
+ *		interfaces and take the endpoint attributes from there.
+ *		Unbelievably, the Philips USB DAC has a sampling rate range
+ *		of over a decade, yet does not support the sampling rate control!
+ *		No wonder it sounds so bad, has very audible sampling rate
+ *		conversion distortion. Don't try to listen to it using
+ *		decent headphones!
+ *		"Let's make things better" -> but please Philips start with your
+ *		own stuff!!!!
+ * 1999-11-02:  Thomas Sailer
+ *		It takes the Philips boxes several seconds to acquire synchronisation
+ *		that means they won't play short sounds. Should probably maintain
+ *		the ISO datastream even if there's nothing to play.
+ *		Fix counting the total_bytes counter, RealPlayer G2 depends on it.
+ * 1999-12-20:  Thomas Sailer
+ *		Fix bad bug in conversion to per interface probing.
+ *		disconnect was called multiple times for the audio device,
+ *		leading to a premature freeing of the audio structures
+ * 2000-05-13:  Thomas Sailer
+ *		I don't remember who changed the find_format routine,
+ *              but the change was completely broken for the Dallas
+ *              chip. Anyway taking sampling rate into account in find_format
+ *              is bad and should not be done unless there are devices with
+ *              completely broken audio descriptors. Unless someone shows
+ *              me such a descriptor, I will not allow find_format to
+ *              take the sampling rate into account.
+ *              Also, the former find_format made:
+ *              - mpg123 play mono instead of stereo
+ *              - sox completely fail for wav's with sample rates < 44.1kHz
+ *                  for the Dallas chip.
+ *              Also fix a rather long standing problem with applications that
+ *              use "small" writes producing no sound at all.
+ * 2000-05-15:  Thomas Sailer
+ *		My fears came true, the Philips camera indeed has pretty stupid
+ *              audio descriptors.
+ * 2000-05-17:  Thomas Sailer
+ *		Nemsoft spotted my stupid last minute change, thanks
+ * 2000-05-19:  Thomas Sailer
+ *		Fixed FEATURE_UNIT thinkos found thanks to the KC Technology
+ *              Xtend device. Basically the driver treated FEATURE_UNIT's sourced
+ *              by mono terminals as stereo.
+ * 2000-05-20:  Thomas Sailer
+ *		SELECTOR support (and thus selecting record channels from the mixer).
+ *              Somewhat peculiar due to OSS interface limitations. Only works
+ *              for channels where a "slider" is already in front of it (i.e.
+ *              a MIXER unit or a FEATURE unit with volume capability).
+ * 2000-11-26:  Thomas Sailer
+ *              Workaround for Dallas DS4201. The DS4201 uses PCM8 as format tag for
+ *              its 8 bit modes, but expects signed data (and should therefore have used PCM).
+ *
+ */
+
+/*
+ * Strategy:
+ *
+ * Alan Cox and Thomas Sailer are starting to dig at opposite ends and
+ * are hoping to meet in the middle, just like tunnel diggers :)
+ * Alan tackles the descriptor parsing, Thomas the actual data IO and the
+ * OSS compatible interface.
+ *
+ * Data IO implementation issues
+ *
+ * A mmap'able ring buffer per direction is implemented, because
+ * almost every OSS app expects it. It is however impractical to
+ * transmit/receive USB data directly into and out of the ring buffer,
+ * due to alignment and synchronisation issues. Instead, the ring buffer
+ * feeds a constant time delay line that handles the USB issues.
+ *
+ * Now we first try to find an alternate setting that exactly matches
+ * the sample format requested by the user. If we find one, we do not
+ * need to perform any sample rate conversions. If there is no matching
+ * altsetting, we choose the closest one and perform sample format
+ * conversions. We never do sample rate conversion; these are too
+ * expensive to be performed in the kernel.
+ *
+ * Current status:
+ * - Pretty stable on UHCI-Acher/Fliegl/Sailer
+ * - Does not work on OHCI due to lack of OHCI driver supporting URB's
+ *
+ * Generally: Due to the brokenness of the Audio Class spec
+ * it seems generally impossible to write a generic Audio Class driver,
+ * so a reasonable driver should implement the features that are actually
+ * used.
+ *
+ * Parsing implementation issues
+ *
+ * One cannot reasonably parse the AudioClass descriptors linearly.
+ * Therefore the current implementation features routines to look
+ * for a specific descriptor in the descriptor list.
+ *
+ * How does the parsing work? First, all interfaces are searched
+ * for an AudioControl class interface. If found, the config descriptor
+ * that belongs to the current configuration is fetched from the device.
+ * Then the HEADER descriptor is fetched. It contains a list of
+ * all AudioStreaming and MIDIStreaming devices. This list is then walked,
+ * and all AudioStreaming interfaces are classified into input and output
+ * interfaces (according to the endpoint0 direction in altsetting1) (MIDIStreaming
+ * is currently not supported). The input & output list is then used
+ * to group inputs and outputs together and issued pairwise to the
+ * AudioStreaming class parser. Finally, all OUTPUT_TERMINAL descriptors
+ * are walked and issued to the mixer construction routine.
+ *
+ * The AudioStreaming parser simply enumerates all altsettings belonging
+ * to the specified interface. It looks for AS_GENERAL and FORMAT_TYPE
+ * class specific descriptors to extract the sample format/sample rate
+ * data. Only sample format types PCM and PCM8 are supported right now, and
+ * only FORMAT_TYPE_I is handled. The isochronous data endpoint needs to
+ * be the first endpoint of the interface, and the optional synchronisation
+ * isochronous endpoint the second one.
+ *
+ * Mixer construction works as follows: The various TERMINAL and UNIT
+ * descriptors span a tree from the root (OUTPUT_TERMINAL) through the
+ * intermediate nodes (UNITs) to the leaves (INPUT_TERMINAL). We walk
+ * that tree in a depth first manner. FEATURE_UNITs may contribute volume,
+ * bass and treble sliders to the mixer, MIXER_UNITs volume sliders.
+ * The terminal type encoded in the INPUT_TERMINALs feeds a heuristic
+ * to determine "meaningful" OSS slider numbers, however we will see
+ * how well this works in practice. Other features are not used at the
+ * moment, they seem less often used. Also, it seems difficult at least
+ * to construct recording source switches from SELECTOR_UNITs, but
+ * since there are not many USB ADC's available, we leave that for later.
+ */
+
+/*****************************************************************************/
+
+#include <linux/version.h>
 #include <linux/kernel.h>
 #include <linux/malloc.h>
 #include <linux/string.h>
 #include <linux/timer.h>
 #include <linux/sched.h>
-#include "usb.h"
+#include <linux/module.h>
+#include <linux/sound.h>
+#include <linux/soundcard.h>
+#include <linux/list.h>
+#include <linux/vmalloc.h>
+#include <linux/wrapper.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <linux/bitops.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+#include <linux/usb.h>
 
-static int usb_audio_probe(struct usb_device *dev);
-static void usb_audio_disconnect(struct usb_device *dev);
-static LIST_HEAD(usb_audio_list);
+#include "audio.h"
 
-struct usb_audio
-{
-	struct usb_device *dev;
+#define AUDIO_DEBUG 1
+
+#define SND_DEV_DSP16   5 
+
+#define dprintk(x)
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * Linked list of all audio devices...
+ */
+static struct list_head audiodevs = LIST_HEAD_INIT(audiodevs);
+static DECLARE_MUTEX(open_sem);
+
+/*
+ * wait queue for processes wanting to open an USB audio device
+ */
+static DECLARE_WAIT_QUEUE_HEAD(open_wait);
+
+
+#define MAXFORMATS        MAX_ALT
+#define DMABUFSHIFT       17  /* 128k worth of DMA buffer */
+#define NRSGBUF           (1U<<(DMABUFSHIFT-PAGE_SHIFT))
+
+/*
+ * This influences:
+ * - Latency
+ * - Interrupt rate
+ * - Synchronisation behaviour
+ * Don't touch this if you don't understand all of the above.
+ */
+#define DESCFRAMES  5
+#define SYNCFRAMES  DESCFRAMES
+
+#define MIXFLG_STEREOIN   1
+#define MIXFLG_STEREOOUT  2
+
+struct mixerchannel {
+	__u16 value;
+	__u16 osschannel;  /* number of the OSS channel */
+	__s16 minval, maxval;
+	__u16 slctunitid;
+	__u8 unitid;
+	__u8 selector;
+	__u8 chnum;
+	__u8 flags;
+};
+
+struct audioformat {
+	unsigned int format;
+	unsigned int sratelo;
+	unsigned int sratehi;
+	unsigned char altsetting;
+	unsigned char attributes;
+};
+
+struct dmabuf {
+	/* buffer data format */
+	unsigned int format;
+	unsigned int srate;
+	/* physical buffer */
+	unsigned char *sgbuf[NRSGBUF];
+	unsigned bufsize;
+	unsigned numfrag;
+	unsigned fragshift;
+	unsigned wrptr, rdptr;
+	unsigned total_bytes;
+	int count;
+	unsigned error; /* over/underrun */
+	wait_queue_head_t wait;
+	/* redundant, but makes calculations easier */
+	unsigned fragsize;
+	unsigned dmasize;
+	/* OSS stuff */
+	unsigned mapped:1;
+	unsigned ready:1;
+	unsigned ossfragshift;
+	int ossmaxfrags;
+	unsigned subdivision;
+};
+
+struct usb_audio_state;
+
+#define FLG_URB0RUNNING   1
+#define FLG_URB1RUNNING   2
+#define FLG_SYNC0RUNNING  4
+#define FLG_SYNC1RUNNING  8
+#define FLG_RUNNING      16
+#define FLG_CONNECTED    32
+
+struct my_data_urb {
+	urb_t urb;
+	iso_packet_descriptor_t isoframe[DESCFRAMES];
+};
+
+struct my_sync_urb {
+	urb_t urb;
+	iso_packet_descriptor_t isoframe[SYNCFRAMES];
+};
+
+
+struct usb_audiodev {
+	struct list_head list;
+	struct usb_audio_state *state;
+	
+	/* soundcore stuff */
+	int dev_audio;
+
+	/* wave stuff */
+	mode_t open_mode;
+	spinlock_t lock;         /* DMA buffer access spinlock */
+
+	struct usbin {
+		int interface;           /* Interface number, -1 means not used */
+		unsigned int format;     /* USB data format */
+		unsigned int datapipe;   /* the data input pipe */
+		unsigned int syncpipe;   /* the synchronisation pipe - 0 for anything but adaptive IN mode */
+		unsigned int syncinterval;  /* P for adaptive IN mode, 0 otherwise */
+		unsigned int freqn;      /* nominal sampling rate in USB format, i.e. fs/1000 in Q10.14 */
+		unsigned int freqmax;    /* maximum sampling rate, used for buffer management */
+		unsigned int phase;      /* phase accumulator */
+		unsigned int flags;      /* see FLG_ defines */
+		
+		struct my_data_urb durb[2];  /* ISO descriptors for the data endpoint */
+		struct my_sync_urb surb[2];  /* ISO sync pipe descriptor if needed */
+		
+		struct dmabuf dma;
+	} usbin;
+
+	struct usbout {
+		int interface;           /* Interface number, -1 means not used */
+		unsigned int format;     /* USB data format */
+		unsigned int datapipe;   /* the data input pipe */
+		unsigned int syncpipe;   /* the synchronisation pipe - 0 for anything but asynchronous OUT mode */
+		unsigned int syncinterval;  /* P for asynchronous OUT mode, 0 otherwise */
+		unsigned int freqn;      /* nominal sampling rate in USB format, i.e. fs/1000 in Q10.14 */
+		unsigned int freqm;      /* momentary sampling rate in USB format, i.e. fs/1000 in Q10.14 */
+		unsigned int freqmax;    /* maximum sampling rate, used for buffer management */
+		unsigned int phase;      /* phase accumulator */
+		unsigned int flags;      /* see FLG_ defines */
+
+		struct my_data_urb durb[2];  /* ISO descriptors for the data endpoint */
+		struct my_sync_urb surb[2];  /* ISO sync pipe descriptor if needed */
+		
+		struct dmabuf dma;
+	} usbout;
+
+
+	unsigned int numfmtin, numfmtout;
+	struct audioformat fmtin[MAXFORMATS];
+	struct audioformat fmtout[MAXFORMATS];
+};  
+
+struct usb_mixerdev {
 	struct list_head list;
+	struct usb_audio_state *state;
+
+	/* soundcore stuff */
+	int dev_mixer;
+
+	unsigned char iface;  /* interface number of the AudioControl interface */
+
+	/* USB format descriptions */
+	unsigned int numch, modcnt;
+
+	/* mixch is last and gets allocated dynamically */
+	struct mixerchannel ch[0];
 };
 
-static struct usb_driver usb_audio_driver =
-{
-	"audio",
-	usb_audio_probe,
-	usb_audio_disconnect,
-	{NULL, NULL}
+struct usb_audio_state {
+	struct list_head audiodev;
+
+	/* USB device */
+	struct usb_device *usbdev;
+
+	struct list_head audiolist;
+	struct list_head mixerlist;
+
+	unsigned count;  /* usage counter; NOTE: the usb stack is also considered a user */
 };
 
+/* private audio format extensions */
+#define AFMT_STEREO        0x80000000
+#define AFMT_ISSTEREO(x)   ((x) & AFMT_STEREO)
+#define AFMT_IS16BIT(x)    ((x) & (AFMT_S16_LE|AFMT_S16_BE|AFMT_U16_LE|AFMT_U16_BE))
+#define AFMT_ISUNSIGNED(x) ((x) & (AFMT_U8|AFMT_U16_LE|AFMT_U16_BE))
+#define AFMT_BYTESSHIFT(x) ((AFMT_ISSTEREO(x) ? 1 : 0) + (AFMT_IS16BIT(x) ? 1 : 0))
+#define AFMT_BYTES(x)      (1<<AFMT_BYTESSHFIT(x))
+
+/* --------------------------------------------------------------------- */
 
-static int usb_audio_irq(int state, void *buffer, void *dev_id)
+extern inline unsigned ld2(unsigned int x)
 {
-	struct usb_audio *aud = (struct usb_audio*) dev_id;
-	return 1;
+	unsigned r = 0;
+	
+	if (x >= 0x10000) {
+		x >>= 16;
+		r += 16;
+	}
+	if (x >= 0x100) {
+		x >>= 8;
+		r += 8;
+	}
+	if (x >= 0x10) {
+		x >>= 4;
+		r += 4;
+	}
+	if (x >= 4) {
+		x >>= 2;
+		r += 2;
+	}
+	if (x >= 2)
+		r++;
+	return r;
+}
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * OSS compatible ring buffer management. The ring buffer may be mmap'ed into
+ * an application address space.
+ *
+ * I first used the rvmalloc stuff copied from bttv. Alan Cox did not like it, so
+ * we now use an array of pointers to a single page each. This saves us the
+ * kernel page table manipulations, but we have to do a page table alike mechanism
+ * (though only one indirection) in software.
+ */
+
+static void dmabuf_release(struct dmabuf *db)
+{
+	unsigned int nr;
+	void *p;
+
+	for(nr = 0; nr < NRSGBUF; nr++) {
+		if (!(p = db->sgbuf[nr]))
+			continue;
+		mem_map_unreserve(MAP_NR(p));
+		free_page((unsigned long)p);
+		db->sgbuf[nr] = NULL;
+	}
+	db->mapped = db->ready = 0;
 }
 
-static int usb_audio_probe(struct usb_device *dev)
+static int dmabuf_init(struct dmabuf *db)
 {
-	struct usb_interface_descriptor *interface;
-	struct usb_endpoint_descriptor *endpoint;
-	struct usb_audio *aud;
+	unsigned int nr, bytepersec, bufs;
+	void *p;
 
-	int i;
-	int na=0;
-	
-	interface = &dev->config[0].interface[0];
+	/* initialize some fields */
+	db->rdptr = db->wrptr = db->total_bytes = db->count = db->error = 0;
+	/* calculate required buffer size */
+	bytepersec = db->srate << AFMT_BYTESSHIFT(db->format);
+	bufs = 1U << DMABUFSHIFT;
+	if (db->ossfragshift) {
+		if ((1000 << db->ossfragshift) < bytepersec)
+			db->fragshift = ld2(bytepersec/1000);
+		else
+			db->fragshift = db->ossfragshift;
+	} else {
+		db->fragshift = ld2(bytepersec/100/(db->subdivision ? db->subdivision : 1));
+		if (db->fragshift < 3)
+			db->fragshift = 3;
+	}
+	db->numfrag = bufs >> db->fragshift;
+	while (db->numfrag < 4 && db->fragshift > 3) {
+		db->fragshift--;
+		db->numfrag = bufs >> db->fragshift;
+	}
+	db->fragsize = 1 << db->fragshift;
+	if (db->ossmaxfrags >= 4 && db->ossmaxfrags < db->numfrag)
+		db->numfrag = db->ossmaxfrags;
+	db->dmasize = db->numfrag << db->fragshift;
+	for(nr = 0; nr < NRSGBUF; nr++) {
+		if (!db->sgbuf[nr]) {
+			p = (void *)get_free_page(GFP_KERNEL);
+			if (!p)
+				return -ENOMEM;
+			db->sgbuf[nr] = p;
+			mem_map_reserve(MAP_NR(p));
+		}
+		memset(db->sgbuf[nr], AFMT_ISUNSIGNED(db->format) ? 0x80 : 0, PAGE_SIZE);
+		if ((nr << PAGE_SHIFT) >= db->dmasize)
+			break;
+	}
+	db->bufsize = nr << PAGE_SHIFT;
+	db->ready = 1;
+	dprintk((KERN_DEBUG "dmabuf_init: bytepersec %d bufs %d ossfragshift %d ossmaxfrags %d "
+	       "fragshift %d fragsize %d numfrag %d dmasize %d bufsize %d fmt 0x%x\n",
+	       bytepersec, bufs, db->ossfragshift, db->ossmaxfrags, db->fragshift, db->fragsize,
+	       db->numfrag, db->dmasize, db->bufsize, db->format));
+	return 0;
+}
+
+static int dmabuf_mmap(struct dmabuf *db, unsigned long start, unsigned long size, pgprot_t prot)
+{
+	unsigned int nr;
+
+	if (!db->ready || db->mapped || (start | size) & (PAGE_SIZE-1) || size > db->bufsize)
+		return -EINVAL;
+	size >>= PAGE_SHIFT;
+	for(nr = 0; nr < size; nr++)
+		if (!db->sgbuf[nr])
+			return -EINVAL;
+	db->mapped = 1;
+	for(nr = 0; nr < size; nr++) {
+		if (remap_page_range(start, virt_to_phys(db->sgbuf[nr]), PAGE_SIZE, prot))
+			return -EAGAIN;
+		start += PAGE_SIZE;
+	}
+	return 0;
+}
+
+static void dmabuf_copyin(struct dmabuf *db, const void *buffer, unsigned int size)
+{
+	unsigned int pgrem, rem;
+
+	db->total_bytes += size;
+	for (;;) {
+		if (size <= 0)
+			return;
+		pgrem = ((~db->wrptr) & (PAGE_SIZE-1)) + 1;
+		if (pgrem > size)
+			pgrem = size;
+		rem = db->dmasize - db->wrptr;
+		if (pgrem > rem)
+			pgrem = rem;
+		memcpy((db->sgbuf[db->wrptr >> PAGE_SHIFT]) + (db->wrptr & (PAGE_SIZE-1)), buffer, pgrem);
+		size -= pgrem;
+		(char *)buffer += pgrem;
+		db->wrptr += pgrem;
+		if (db->wrptr >= db->dmasize)
+			db->wrptr = 0;
+	}
+}
+
+static void dmabuf_copyout(struct dmabuf *db, void *buffer, unsigned int size)
+{
+	unsigned int pgrem, rem;
+
+	db->total_bytes += size;
+	for (;;) {
+		if (size <= 0)
+			return;
+		pgrem = ((~db->rdptr) & (PAGE_SIZE-1)) + 1;
+		if (pgrem > size)
+			pgrem = size;
+		rem = db->dmasize - db->rdptr;
+		if (pgrem > rem)
+			pgrem = rem;
+		memcpy(buffer, (db->sgbuf[db->rdptr >> PAGE_SHIFT]) + (db->rdptr & (PAGE_SIZE-1)), pgrem);
+		size -= pgrem;
+		(char *)buffer += pgrem;
+		db->rdptr += pgrem;
+		if (db->rdptr >= db->dmasize)
+			db->rdptr = 0;
+	}
+}
+
+static int dmabuf_copyin_user(struct dmabuf *db, unsigned int ptr, const void *buffer, unsigned int size)
+{
+	unsigned int pgrem, rem;
+
+	if (!db->ready || db->mapped)
+		return -EINVAL;
+	for (;;) {
+		if (size <= 0)
+			return 0;
+		pgrem = ((~ptr) & (PAGE_SIZE-1)) + 1;
+		if (pgrem > size)
+			pgrem = size;
+		rem = db->dmasize - ptr;
+		if (pgrem > rem)
+			pgrem = rem;
+		copy_from_user_ret((db->sgbuf[ptr >> PAGE_SHIFT]) + (ptr & (PAGE_SIZE-1)), buffer, pgrem, -EFAULT);
+		size -= pgrem;
+		(char *)buffer += pgrem;
+		ptr += pgrem;
+		if (ptr >= db->dmasize)
+			ptr = 0;
+	}
+}
+
+static int dmabuf_copyout_user(struct dmabuf *db, unsigned int ptr, void *buffer, unsigned int size)
+{
+	unsigned int pgrem, rem;
+
+	if (!db->ready || db->mapped)
+		return -EINVAL;
+	for (;;) {
+		if (size <= 0)
+			return 0;
+		pgrem = ((~ptr) & (PAGE_SIZE-1)) + 1;
+		if (pgrem > size)
+			pgrem = size;
+		rem = db->dmasize - ptr;
+		if (pgrem > rem)
+			pgrem = rem;
+		copy_to_user_ret(buffer, (db->sgbuf[ptr >> PAGE_SHIFT]) + (ptr & (PAGE_SIZE-1)), pgrem, -EFAULT);
+		size -= pgrem;
+		(char *)buffer += pgrem;
+		ptr += pgrem;
+		if (ptr >= db->dmasize)
+			ptr = 0;
+	}
+}
+
+/* --------------------------------------------------------------------- */
+/*
+ * USB I/O code. We do sample format conversion if necessary
+ */
+
+static void usbin_stop(struct usb_audiodev *as)
+{
+	struct usbin *u = &as->usbin;
+	unsigned long flags;
+	unsigned int i, notkilled = 1;
+
+	spin_lock_irqsave(&as->lock, flags);
+	u->flags &= ~FLG_RUNNING;
+	i = u->flags;
+	spin_unlock_irqrestore(&as->lock, flags);
+	while (i & (FLG_URB0RUNNING|FLG_URB1RUNNING|FLG_SYNC0RUNNING|FLG_SYNC1RUNNING)) {
+		set_current_state(notkilled ? TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE);
+		schedule_timeout(1);
+		spin_lock_irqsave(&as->lock, flags);
+		i = u->flags;
+		spin_unlock_irqrestore(&as->lock, flags);
+		if (notkilled && signal_pending(current)) {
+			if (i & FLG_URB0RUNNING)
+				usb_unlink_urb(&u->durb[0].urb);
+			if (i & FLG_URB1RUNNING)
+				usb_unlink_urb(&u->durb[1].urb);
+			if (i & FLG_SYNC0RUNNING)
+				usb_unlink_urb(&u->surb[0].urb);
+			if (i & FLG_SYNC1RUNNING)
+				usb_unlink_urb(&u->surb[1].urb);
+			notkilled = 0;
+		}
+	}
+	set_current_state(TASK_RUNNING);
+	if (u->durb[0].urb.transfer_buffer)
+		kfree(u->durb[0].urb.transfer_buffer);
+	if (u->durb[1].urb.transfer_buffer)
+		kfree(u->durb[1].urb.transfer_buffer);
+	if (u->surb[0].urb.transfer_buffer)
+		kfree(u->surb[0].urb.transfer_buffer);
+	if (u->surb[1].urb.transfer_buffer)
+		kfree(u->surb[1].urb.transfer_buffer);
+	u->durb[0].urb.transfer_buffer = u->durb[1].urb.transfer_buffer = 
+		u->surb[0].urb.transfer_buffer = u->surb[1].urb.transfer_buffer = NULL;
+}
+
+static inline void usbin_release(struct usb_audiodev *as)
+{
+	usbin_stop(as);
+}
+
+static void usbin_disc(struct usb_audiodev *as)
+{
+	struct usbin *u = &as->usbin;
+
+	unsigned long flags;
+
+	spin_lock_irqsave(&as->lock, flags);
+	u->flags &= ~(FLG_RUNNING | FLG_CONNECTED);
+	spin_unlock_irqrestore(&as->lock, flags);
+	usbin_stop(as);
+}
+
+static void conversion(const void *ibuf, unsigned int ifmt, void *obuf, unsigned int ofmt, void *tmp, unsigned int scnt)
+{
+	unsigned int cnt, i;
+	__s16 *sp, *sp2, s;
+	unsigned char *bp;
 
-	for(i=0;i<dev->config[0].bNumInterfaces;i++)
-	{
-		int x;
+	cnt = scnt;
+	if (AFMT_ISSTEREO(ifmt))
+		cnt <<= 1;
+	sp = ((__s16 *)tmp) + cnt;
+	switch (ifmt & ~AFMT_STEREO) {
+	case AFMT_U8:
+		for (bp = ((unsigned char *)ibuf)+cnt, i = 0; i < cnt; i++) {
+			bp--;
+			sp--;
+			*sp = (*bp ^ 0x80) << 8;
+		}
+		break;
+			
+	case AFMT_S8:
+		for (bp = ((unsigned char *)ibuf)+cnt, i = 0; i < cnt; i++) {
+			bp--;
+			sp--;
+			*sp = *bp << 8;
+		}
+		break;
 		
-		endpoint = &interface->endpoint[i];
+	case AFMT_U16_LE:
+		for (bp = ((unsigned char *)ibuf)+2*cnt, i = 0; i < cnt; i++) {
+			bp -= 2;
+			sp--;
+			*sp = (bp[0] | (bp[1] << 8)) ^ 0x8000;
+		}
+		break;
+
+	case AFMT_U16_BE:
+		for (bp = ((unsigned char *)ibuf)+2*cnt, i = 0; i < cnt; i++) {
+			bp -= 2;
+			sp--;
+			*sp = (bp[1] | (bp[0] << 8)) ^ 0x8000;
+		}
+		break;
+
+	case AFMT_S16_LE:
+		for (bp = ((unsigned char *)ibuf)+2*cnt, i = 0; i < cnt; i++) {
+			bp -= 2;
+			sp--;
+			*sp = bp[0] | (bp[1] << 8);
+		}
+		break;
+
+	case AFMT_S16_BE:
+		for (bp = ((unsigned char *)ibuf)+2*cnt, i = 0; i < cnt; i++) {
+			bp -= 2;
+			sp--;
+			*sp = bp[1] | (bp[0] << 8);
+		}
+		break;
+	}
+	if (!AFMT_ISSTEREO(ifmt) && AFMT_ISSTEREO(ofmt)) {
+		/* expand from mono to stereo */
+		for (sp = ((__s16 *)tmp)+scnt, sp2 = ((__s16 *)tmp)+2*scnt, i = 0; i < scnt; i++) {
+			sp--;
+			sp2 -= 2;
+			sp2[0] = sp2[1] = sp[0];
+		}
+	}
+	if (AFMT_ISSTEREO(ifmt) && !AFMT_ISSTEREO(ofmt)) {
+		/* contract from stereo to mono */
+		for (sp = sp2 = ((__s16 *)tmp), i = 0; i < scnt; i++, sp++, sp2 += 2)
+			sp[0] = (sp2[0] + sp2[1]) >> 1;
+	}
+	cnt = scnt;
+	if (AFMT_ISSTEREO(ofmt))
+		cnt <<= 1;
+	sp = ((__s16 *)tmp);
+	bp = ((unsigned char *)obuf);
+	switch (ofmt & ~AFMT_STEREO) {
+	case AFMT_U8:
+		for (i = 0; i < cnt; i++, sp++, bp++)
+			*bp = (*sp >> 8) ^ 0x80;
+		break;
+
+	case AFMT_S8:
+		for (i = 0; i < cnt; i++, sp++, bp++)
+			*bp = *sp >> 8;
+		break;
+
+	case AFMT_U16_LE:
+		for (i = 0; i < cnt; i++, sp++, bp += 2) {
+			s = *sp;
+			bp[0] = s;
+			bp[1] = (s >> 8) ^ 0x80;
+		}
+		break;
+
+	case AFMT_U16_BE:
+		for (i = 0; i < cnt; i++, sp++, bp += 2) {
+			s = *sp;
+			bp[1] = s;
+			bp[0] = (s >> 8) ^ 0x80;
+		}
+		break;
 
-		if(interface->bInterfaceClass != 1) 
-	        	continue;
+	case AFMT_S16_LE:
+		for (i = 0; i < cnt; i++, sp++, bp += 2) {
+			s = *sp;
+			bp[0] = s;
+			bp[1] = s >> 8;
+		}
+		break;
 
-		printk(KERN_INFO "USB audio device detected.\n");
+	case AFMT_S16_BE:
+		for (i = 0; i < cnt; i++, sp++, bp += 2) {
+			s = *sp;
+			bp[1] = s;
+			bp[0] = s >> 8;
+		}
+		break;
+	}
 	
-		switch(interface->bInterfaceSubClass)
-		{
-			case 0x01:
-				printk(KERN_INFO "audio: Control device.\n");
-				break;
-			case 0x02:
-				printk(KERN_INFO "audio: streaming.\n");
-				break;
-			case 0x03:
-				printk(KERN_INFO "audio: nonstreaming.\n");
-				break;
+}
+
+static void usbin_convert(struct usbin *u, unsigned char *buffer, unsigned int samples)
+{
+	union {
+		__s16 s[64];
+		unsigned char b[0];
+	} tmp;
+	unsigned int scnt, maxs, ufmtsh, dfmtsh;
+
+	ufmtsh = AFMT_BYTESSHIFT(u->format);
+	dfmtsh = AFMT_BYTESSHIFT(u->dma.format);
+	maxs = (AFMT_ISSTEREO(u->dma.format | u->format)) ? 32 : 64;
+	while (samples > 0) {
+		scnt = samples;
+		if (scnt > maxs)
+			scnt = maxs;
+		conversion(buffer, u->format, tmp.b, u->dma.format, tmp.b, scnt);
+		dmabuf_copyin(&u->dma, tmp.b, scnt << dfmtsh);
+		buffer += scnt << ufmtsh;
+		samples -= scnt;
+	}
+}		
+
+static int usbin_prepare_desc(struct usbin *u, purb_t urb)
+{
+	unsigned int i, maxsize, offs;
+
+	maxsize = (u->freqmax + 0x3fff) >> (14 - AFMT_BYTESSHIFT(u->format));
+	//printk(KERN_DEBUG "usbin_prepare_desc: maxsize %d freq 0x%x format 0x%x\n", maxsize, u->freqn, u->format);
+	for (i = offs = 0; i < DESCFRAMES; i++, offs += maxsize) {
+		urb->iso_frame_desc[i].length = maxsize;
+		urb->iso_frame_desc[i].offset = offs;
+	}
+	return 0;
+}
+
+/*
+ * return value: 0 if descriptor should be restarted, -1 otherwise
+ * convert sample format on the fly if necessary
+ */
+static int usbin_retire_desc(struct usbin *u, purb_t urb)
+{
+	unsigned int i, ufmtsh, dfmtsh, err = 0, cnt, scnt, dmafree;
+	unsigned char *cp;
+
+	ufmtsh = AFMT_BYTESSHIFT(u->format);
+	dfmtsh = AFMT_BYTESSHIFT(u->dma.format);
+	for (i = 0; i < DESCFRAMES; i++) {
+		cp = ((unsigned char *)urb->transfer_buffer) + urb->iso_frame_desc[i].offset;
+		if (urb->iso_frame_desc[i].status) {
+			dprintk((KERN_DEBUG "usbin_retire_desc: frame %u status %d\n", i, urb->iso_frame_desc[i].status));
+			continue;
+		}
+		scnt = urb->iso_frame_desc[i].actual_length >> ufmtsh;
+		if (!scnt)
+			continue;
+		cnt = scnt << dfmtsh;
+		if (!u->dma.mapped) {
+			dmafree = u->dma.dmasize - u->dma.count;
+			if (cnt > dmafree) {
+				scnt = dmafree >> dfmtsh;
+				cnt = scnt << dfmtsh;
+				err++;
+			}
 		}
-		na++;
+		u->dma.count += cnt;
+		if (u->format == u->dma.format) {
+			/* we do not need format conversion */
+			dmabuf_copyin(&u->dma, cp, cnt);
+		} else {
+			/* we need sampling format conversion */
+			usbin_convert(u, cp, scnt);
+		}
+	}
+	if (err)
+		u->dma.error++;
+	if (u->dma.count >= (signed)u->dma.fragsize)
+		wake_up(&u->dma.wait);
+	return err ? -1 : 0;
+}
+
+static void usbin_completed(struct urb *urb)
+{
+	struct usb_audiodev *as = (struct usb_audiodev *)urb->context;
+	struct usbin *u = &as->usbin;
+	unsigned long flags;
+	unsigned int mask;
+	int suret = USB_ST_NOERROR;
+
+#if 0
+	printk(KERN_DEBUG "usbin_completed: status %d errcnt %d flags 0x%x\n", urb->status, urb->error_count, u->flags);
+#endif
+	if (urb == &u->durb[0].urb)
+		mask = FLG_URB0RUNNING;
+	else if (urb == &u->durb[1].urb)
+		mask = FLG_URB1RUNNING;
+	else {
+		mask = 0;
+		printk(KERN_ERR "usbin_completed: panic: unknown URB\n");
 	}
+	urb->dev = as->state->usbdev;
+	spin_lock_irqsave(&as->lock, flags);
+	if (!usbin_retire_desc(u, urb) &&
+	    u->flags & FLG_RUNNING &&
+	    !usbin_prepare_desc(u, urb) && 
+	    (suret = usb_submit_urb(urb)) == USB_ST_NOERROR) {
+		u->flags |= mask;
+	} else {
+		u->flags &= ~(mask | FLG_RUNNING);
+		wake_up(&u->dma.wait);
+		printk(KERN_DEBUG "usbin_completed: descriptor not restarted (usb_submit_urb: %d)\n", suret);
+	}
+	spin_unlock_irqrestore(&as->lock, flags);
+}
+
+/*
+ * we output sync data
+ */
+static int usbin_sync_prepare_desc(struct usbin *u, purb_t urb)
+{
+	unsigned char *cp = urb->transfer_buffer;
+	unsigned int i, offs;
 	
-	if(na==0)
-		return -1;
+	for (i = offs = 0; i < SYNCFRAMES; i++, offs += 3, cp += 3) {
+		urb->iso_frame_desc[i].length = 3;
+		urb->iso_frame_desc[i].offset = offs;
+		cp[0] = u->freqn;
+		cp[1] = u->freqn >> 8;
+		cp[2] = u->freqn >> 16;
+	}
+	return 0;
+}
+
+/*
+ * return value: 0 if descriptor should be restarted, -1 otherwise
+ */
+static int usbin_sync_retire_desc(struct usbin *u, purb_t urb)
+{
+	unsigned int i;
+	
+	for (i = 0; i < SYNCFRAMES; i++)
+		if (urb->iso_frame_desc[0].status)
+			dprintk((KERN_DEBUG "usbin_sync_retire_desc: frame %u status %d\n", i, urb->iso_frame_desc[i].status));
+	return 0;
+}
 
-	aud = kmalloc(sizeof(struct usb_audio), GFP_KERNEL);
-	if(aud)
-	{
-        	memset(aud, 0, sizeof(*aud));
-        	aud->dev = dev;
-        	dev->private = aud;
+static void usbin_sync_completed(struct urb *urb)
+{
+	struct usb_audiodev *as = (struct usb_audiodev *)urb->context;
+	struct usbin *u = &as->usbin;
+	unsigned long flags;
+	unsigned int mask;
+	int suret = USB_ST_NOERROR;
 
-		endpoint = &interface->endpoint[0];
+#if 0
+	printk(KERN_DEBUG "usbin_sync_completed: status %d errcnt %d flags 0x%x\n", urb->status, urb->error_count, u->flags);
+#endif
+	if (urb == &u->surb[0].urb)
+		mask = FLG_SYNC0RUNNING;
+	else if (urb == &u->surb[1].urb)
+		mask = FLG_SYNC1RUNNING;
+	else {
+		mask = 0;
+		printk(KERN_ERR "usbin_sync_completed: panic: unknown URB\n");
+	}
+	urb->dev = as->state->usbdev;
+	spin_lock_irqsave(&as->lock, flags);
+	if (!usbin_sync_retire_desc(u, urb) &&
+	    u->flags & FLG_RUNNING &&
+	    !usbin_sync_prepare_desc(u, urb) && 
+	    (suret = usb_submit_urb(urb)) == USB_ST_NOERROR) {
+		u->flags |= mask;
+	} else {
+		u->flags &= ~(mask | FLG_RUNNING);
+		wake_up(&u->dma.wait);
+		dprintk((KERN_DEBUG "usbin_sync_completed: descriptor not restarted (usb_submit_urb: %d)\n", suret));
+	}
+	spin_unlock_irqrestore(&as->lock, flags);
+}
 
-//        	usb_set_configuration(dev, dev->config[0].bConfigurationValue);
-//        	usb_set_protocol(dev, 0);
-//        	usb_set_idle(dev, 0, 0);
-        
-        	usb_request_irq(dev,
-                        usb_rcvctrlpipe(dev, endpoint->bEndpointAddress),
-                        usb_audio_irq,
-                        endpoint->bInterval,
-                        aud);
+static int usbin_start(struct usb_audiodev *as)
+{
+	struct usb_device *dev = as->state->usbdev;
+	struct usbin *u = &as->usbin;
+	purb_t urb;
+	unsigned long flags;
+	unsigned int maxsze, bufsz;
 
-		list_add(&aud->list, &usb_audio_list);
+#if 0
+	printk(KERN_DEBUG "usbin_start: device %d ufmt 0x%08x dfmt 0x%08x srate %d\n",
+	       dev->devnum, u->format, u->dma.format, u->dma.srate);
+#endif
+	/* allocate USB storage if not already done */
+	spin_lock_irqsave(&as->lock, flags);
+	if (!(u->flags & FLG_CONNECTED)) {
+		spin_unlock_irqrestore(&as->lock, flags);
+		return -EIO;
+	}
+	if (!(u->flags & FLG_RUNNING)) {
+		spin_unlock_irqrestore(&as->lock, flags);
+		u->freqn = ((u->dma.srate << 11) + 62) / 125; /* this will overflow at approx 2MSPS */
+		u->freqmax = u->freqn + (u->freqn >> 2);
+		u->phase = 0;
+		maxsze = (u->freqmax + 0x3fff) >> (14 - AFMT_BYTESSHIFT(u->format));
+		bufsz = DESCFRAMES * maxsze;
+		if (u->durb[0].urb.transfer_buffer)
+			kfree(u->durb[0].urb.transfer_buffer);
+		u->durb[0].urb.transfer_buffer = kmalloc(bufsz, GFP_KERNEL);
+		u->durb[0].urb.transfer_buffer_length = bufsz;
+		if (u->durb[1].urb.transfer_buffer)
+			kfree(u->durb[1].urb.transfer_buffer);
+		u->durb[1].urb.transfer_buffer = kmalloc(bufsz, GFP_KERNEL);
+		u->durb[1].urb.transfer_buffer_length = bufsz;
+		if (u->syncpipe) {
+			if (u->surb[0].urb.transfer_buffer)
+				kfree(u->surb[0].urb.transfer_buffer);
+			u->surb[0].urb.transfer_buffer = kmalloc(3*SYNCFRAMES, GFP_KERNEL);
+			u->surb[0].urb.transfer_buffer_length = 3*SYNCFRAMES;
+			if (u->surb[1].urb.transfer_buffer)
+				kfree(u->surb[1].urb.transfer_buffer);
+			u->surb[1].urb.transfer_buffer = kmalloc(3*SYNCFRAMES, GFP_KERNEL);
+			u->surb[1].urb.transfer_buffer_length = 3*SYNCFRAMES;
+		}
+		if (!u->durb[0].urb.transfer_buffer || !u->durb[1].urb.transfer_buffer || 
+		    (u->syncpipe && (!u->surb[0].urb.transfer_buffer || !u->surb[1].urb.transfer_buffer))) {
+			printk(KERN_ERR "usbaudio: cannot start playback device %d\n", dev->devnum);
+			return 0;
+		}
+		spin_lock_irqsave(&as->lock, flags);
+	}
+	if (u->dma.count >= u->dma.dmasize && !u->dma.mapped) {
+		spin_unlock_irqrestore(&as->lock, flags);
+		return 0;
+	}
+	u->flags |= FLG_RUNNING;
+	if (!(u->flags & FLG_URB0RUNNING)) {
+		urb = &u->durb[0].urb;
+		urb->dev = dev;
+		urb->pipe = u->datapipe;
+		urb->transfer_flags = USB_ISO_ASAP;
+		urb->number_of_packets = DESCFRAMES;
+		urb->context = as;
+		urb->complete = usbin_completed;
+		if (!usbin_prepare_desc(u, urb) && !usb_submit_urb(urb))
+			u->flags |= FLG_URB0RUNNING;
+		else
+			u->flags &= ~FLG_RUNNING;
+	}
+	if (u->flags & FLG_RUNNING && !(u->flags & FLG_URB1RUNNING)) {
+		urb = &u->durb[1].urb;
+		urb->dev = dev;
+		urb->pipe = u->datapipe;
+		urb->transfer_flags = USB_ISO_ASAP;
+		urb->number_of_packets = DESCFRAMES;
+		urb->context = as;
+		urb->complete = usbin_completed;
+		if (!usbin_prepare_desc(u, urb) && !usb_submit_urb(urb))
+			u->flags |= FLG_URB1RUNNING;
+		else
+			u->flags &= ~FLG_RUNNING;
 	}
+	if (u->syncpipe) {
+		if (u->flags & FLG_RUNNING && !(u->flags & FLG_SYNC0RUNNING)) {
+			urb = &u->surb[0].urb;
+			urb->dev = dev;
+			urb->pipe = u->syncpipe;
+			urb->transfer_flags = USB_ISO_ASAP;
+			urb->number_of_packets = SYNCFRAMES;
+			urb->context = as;
+			urb->complete = usbin_sync_completed;
+			/* stride: u->syncinterval */
+			if (!usbin_sync_prepare_desc(u, urb) && !usb_submit_urb(urb))
+				u->flags |= FLG_SYNC0RUNNING;
+			else
+				u->flags &= ~FLG_RUNNING;
+		}
+		if (u->flags & FLG_RUNNING && !(u->flags & FLG_SYNC1RUNNING)) {
+			urb = &u->surb[1].urb;
+			urb->dev = dev;
+			urb->pipe = u->syncpipe;
+			urb->transfer_flags = USB_ISO_ASAP;
+			urb->number_of_packets = SYNCFRAMES;
+			urb->context = as;
+			urb->complete = usbin_sync_completed;
+			/* stride: u->syncinterval */
+			if (!usbin_sync_prepare_desc(u, urb) && !usb_submit_urb(urb))
+				u->flags |= FLG_SYNC1RUNNING;
+			else
+				u->flags &= ~FLG_RUNNING;
+		}
+	}
+	spin_unlock_irqrestore(&as->lock, flags);
 	return 0;
 }
 
-static void usb_audio_disconnect(struct usb_device *dev)
+static void usbout_stop(struct usb_audiodev *as)
 {
-	struct usb_audio *aud = (struct usb_audio*) dev->private;
-	if(aud)
-	{
-        	dev->private = NULL;
-        	list_del(&aud->list);
-        	kfree(aud);
+	struct usbout *u = &as->usbout;
+	unsigned long flags;
+	unsigned int i, notkilled = 1;
+
+	spin_lock_irqsave(&as->lock, flags);
+	u->flags &= ~FLG_RUNNING;
+	i = u->flags;
+	spin_unlock_irqrestore(&as->lock, flags);
+	while (i & (FLG_URB0RUNNING|FLG_URB1RUNNING|FLG_SYNC0RUNNING|FLG_SYNC1RUNNING)) {
+		set_current_state(notkilled ? TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE);
+		schedule_timeout(1);
+		spin_lock_irqsave(&as->lock, flags);
+		i = u->flags;
+		spin_unlock_irqrestore(&as->lock, flags);
+		if (notkilled && signal_pending(current)) {
+			if (i & FLG_URB0RUNNING)
+				usb_unlink_urb(&u->durb[0].urb);
+			if (i & FLG_URB1RUNNING)
+				usb_unlink_urb(&u->durb[1].urb);
+			if (i & FLG_SYNC0RUNNING)
+				usb_unlink_urb(&u->surb[0].urb);
+			if (i & FLG_SYNC1RUNNING)
+				usb_unlink_urb(&u->surb[1].urb);
+			notkilled = 0;
+		}
 	}
-	printk(KERN_INFO "USB audio driver removed.\n");
+	set_current_state(TASK_RUNNING);
+	if (u->durb[0].urb.transfer_buffer)
+		kfree(u->durb[0].urb.transfer_buffer);
+	if (u->durb[1].urb.transfer_buffer)
+		kfree(u->durb[1].urb.transfer_buffer);
+	if (u->surb[0].urb.transfer_buffer)
+		kfree(u->surb[0].urb.transfer_buffer);
+	if (u->surb[1].urb.transfer_buffer)
+		kfree(u->surb[1].urb.transfer_buffer);
+	u->durb[0].urb.transfer_buffer = u->durb[1].urb.transfer_buffer = 
+		u->surb[0].urb.transfer_buffer = u->surb[1].urb.transfer_buffer = NULL;
 }
 
-int usb_audio_init(void)
+static inline void usbout_release(struct usb_audiodev *as)
 {
-	usb_register(&usb_audio_driver);
+	usbout_stop(as);
+}
+
+static void usbout_disc(struct usb_audiodev *as)
+{
+	struct usbout *u = &as->usbout;
+	unsigned long flags;
+
+	spin_lock_irqsave(&as->lock, flags);
+	u->flags &= ~(FLG_RUNNING | FLG_CONNECTED);
+	spin_unlock_irqrestore(&as->lock, flags);
+	usbout_stop(as);
+}
+
+static void usbout_convert(struct usbout *u, unsigned char *buffer, unsigned int samples)
+{
+	union {
+		__s16 s[64];
+		unsigned char b[0];
+	} tmp;
+	unsigned int scnt, maxs, ufmtsh, dfmtsh;
+
+	ufmtsh = AFMT_BYTESSHIFT(u->format);
+	dfmtsh = AFMT_BYTESSHIFT(u->dma.format);
+	maxs = (AFMT_ISSTEREO(u->dma.format | u->format)) ? 32 : 64;
+	while (samples > 0) {
+		scnt = samples;
+		if (scnt > maxs)
+			scnt = maxs;
+		dmabuf_copyout(&u->dma, tmp.b, scnt << dfmtsh);
+		conversion(tmp.b, u->dma.format, buffer, u->format, tmp.b, scnt);
+		buffer += scnt << ufmtsh;
+		samples -= scnt;
+	}
+}		
+
+static int usbout_prepare_desc(struct usbout *u, purb_t urb)
+{
+	unsigned int i, ufmtsh, dfmtsh, err = 0, cnt, scnt, offs;
+	unsigned char *cp = urb->transfer_buffer;
+
+	ufmtsh = AFMT_BYTESSHIFT(u->format);
+	dfmtsh = AFMT_BYTESSHIFT(u->dma.format);
+	for (i = offs = 0; i < DESCFRAMES; i++) {
+		urb->iso_frame_desc[i].offset = offs;
+		u->phase = (u->phase & 0x3fff) + u->freqm;
+		scnt = u->phase >> 14;
+		if (!scnt) {
+			urb->iso_frame_desc[i].length = 0;
+			continue;
+		}
+		cnt = scnt << dfmtsh;
+		if (!u->dma.mapped) {
+			if (cnt > u->dma.count) {
+				scnt = u->dma.count >> dfmtsh;
+				cnt = scnt << dfmtsh;
+				err++;
+			}
+			u->dma.count -= cnt;
+		} else
+			u->dma.count += cnt;
+		if (u->format == u->dma.format) {
+			/* we do not need format conversion */
+			dmabuf_copyout(&u->dma, cp, cnt);
+		} else {
+			/* we need sampling format conversion */
+			usbout_convert(u, cp, scnt);
+		}
+		cnt = scnt << ufmtsh;
+		urb->iso_frame_desc[i].length = cnt;
+		offs += cnt;
+		cp += cnt;
+	}
+	if (err)
+		u->dma.error++;
+	if (u->dma.mapped) {
+		if (u->dma.count >= (signed)u->dma.fragsize)
+			wake_up(&u->dma.wait);
+	} else {
+		if ((signed)u->dma.dmasize >= u->dma.count + (signed)u->dma.fragsize)
+			wake_up(&u->dma.wait);
+	}
+	return err ? -1 : 0;
+}
+
+/*
+ * return value: 0 if descriptor should be restarted, -1 otherwise
+ */
+static int usbout_retire_desc(struct usbout *u, purb_t urb)
+{
+	unsigned int i;
+
+	for (i = 0; i < DESCFRAMES; i++) {
+		if (urb->iso_frame_desc[i].status) {
+			dprintk((KERN_DEBUG "usbout_retire_desc: frame %u status %d\n", i, urb->iso_frame_desc[i].status));
+			continue;
+		}
+	}
+	return 0;
+}
+
+static void usbout_completed(struct urb *urb)
+{
+	struct usb_audiodev *as = (struct usb_audiodev *)urb->context;
+	struct usbout *u = &as->usbout;
+	unsigned long flags;
+	unsigned int mask;
+	int suret = USB_ST_NOERROR;
+
+#if 0
+	printk(KERN_DEBUG "usbout_completed: status %d errcnt %d flags 0x%x\n", urb->status, urb->error_count, u->flags);
+#endif
+	if (urb == &u->durb[0].urb)
+		mask = FLG_URB0RUNNING;
+	else if (urb == &u->durb[1].urb)
+		mask = FLG_URB1RUNNING;
+	else {
+		mask = 0;
+		printk(KERN_ERR "usbout_completed: panic: unknown URB\n");
+	}
+	urb->dev = as->state->usbdev;
+	spin_lock_irqsave(&as->lock, flags);
+	if (!usbout_retire_desc(u, urb) &&
+	    u->flags & FLG_RUNNING &&
+	    !usbout_prepare_desc(u, urb) && 
+	    (suret = usb_submit_urb(urb)) == USB_ST_NOERROR) {
+		u->flags |= mask;
+	} else {
+		u->flags &= ~(mask | FLG_RUNNING);
+		wake_up(&u->dma.wait);
+		dprintk((KERN_DEBUG "usbout_completed: descriptor not restarted (usb_submit_urb: %d)\n", suret));
+	}
+	spin_unlock_irqrestore(&as->lock, flags);
+}
+
+static int usbout_sync_prepare_desc(struct usbout *u, purb_t urb)
+{
+	unsigned int i, offs;
+
+	for (i = offs = 0; i < SYNCFRAMES; i++, offs += 3) {
+		urb->iso_frame_desc[i].length = 3;
+		urb->iso_frame_desc[i].offset = offs;
+	}
 	return 0;
 }
 
 /*
- *	Support functions for parsing
+ * return value: 0 if descriptor should be restarted, -1 otherwise
  */
- 
-void usb_audio_interface(struct usb_interface_descriptor *interface, u8 *data)
+static int usbout_sync_retire_desc(struct usbout *u, purb_t urb)
+{
+	unsigned char *cp = urb->transfer_buffer;
+	unsigned int f, i;
+
+	for (i = 0; i < SYNCFRAMES; i++, cp += 3) {
+		if (urb->iso_frame_desc[i].status) {
+			dprintk((KERN_DEBUG "usbout_sync_retire_desc: frame %u status %d\n", i, urb->iso_frame_desc[i].status));
+			continue;
+		}
+		if (urb->iso_frame_desc[i].actual_length < 3) {
+			dprintk((KERN_DEBUG "usbout_sync_retire_desc: frame %u length %d\n", i, urb->iso_frame_desc[i].actual_length));
+			continue;
+		}
+		f = cp[0] | (cp[1] << 8) | (cp[2] << 16);
+		if (abs(f - u->freqn) > (u->freqn >> 3) || f > u->freqmax) {
+			printk(KERN_WARNING "usbout_sync_retire_desc: requested frequency %u (nominal %u) out of range!\n", f, u->freqn);
+			continue;
+		}
+		u->freqm = f;
+	}
+	return 0;
+}
+
+static void usbout_sync_completed(struct urb *urb)
+{
+	struct usb_audiodev *as = (struct usb_audiodev *)urb->context;
+	struct usbout *u = &as->usbout;
+	unsigned long flags;
+	unsigned int mask;
+	int suret = USB_ST_NOERROR;
+
+#if 0
+	printk(KERN_DEBUG "usbout_sync_completed: status %d errcnt %d flags 0x%x\n", urb->status, urb->error_count, u->flags);
+#endif
+	if (urb == &u->surb[0].urb)
+		mask = FLG_SYNC0RUNNING;
+	else if (urb == &u->surb[1].urb)
+		mask = FLG_SYNC1RUNNING;
+	else {
+		mask = 0;
+		printk(KERN_ERR "usbout_sync_completed: panic: unknown URB\n");
+	}
+	urb->dev = as->state->usbdev;
+	spin_lock_irqsave(&as->lock, flags);
+	if (!usbout_sync_retire_desc(u, urb) &&
+	    u->flags & FLG_RUNNING &&
+	    !usbout_sync_prepare_desc(u, urb) && 
+	    (suret = usb_submit_urb(urb)) == USB_ST_NOERROR) {
+		u->flags |= mask;
+	} else {
+		u->flags &= ~(mask | FLG_RUNNING);
+		wake_up(&u->dma.wait);
+		dprintk((KERN_DEBUG "usbout_sync_completed: descriptor not restarted (usb_submit_urb: %d)\n", suret));
+	}
+	spin_unlock_irqrestore(&as->lock, flags);
+}
+
+static int usbout_start(struct usb_audiodev *as)
+{
+	struct usb_device *dev = as->state->usbdev;
+	struct usbout *u = &as->usbout;
+	purb_t urb;
+	unsigned long flags;
+	unsigned int maxsze, bufsz;
+
+#if 0
+	printk(KERN_DEBUG "usbout_start: device %d ufmt 0x%08x dfmt 0x%08x srate %d\n",
+	       dev->devnum, u->format, u->dma.format, u->dma.srate);
+#endif
+	/* allocate USB storage if not already done */
+	spin_lock_irqsave(&as->lock, flags);
+	if (!(u->flags & FLG_CONNECTED)) {
+		spin_unlock_irqrestore(&as->lock, flags);
+		return -EIO;
+	}
+	if (!(u->flags & FLG_RUNNING)) {
+		spin_unlock_irqrestore(&as->lock, flags);
+		u->freqn = u->freqm = ((u->dma.srate << 11) + 62) / 125; /* this will overflow at approx 2MSPS */
+		u->freqmax = u->freqn + (u->freqn >> 2);
+		u->phase = 0;
+		maxsze = (u->freqmax + 0x3fff) >> (14 - AFMT_BYTESSHIFT(u->format));
+		bufsz = DESCFRAMES * maxsze;
+		if (u->durb[0].urb.transfer_buffer)
+			kfree(u->durb[0].urb.transfer_buffer);
+		u->durb[0].urb.transfer_buffer = kmalloc(bufsz, GFP_KERNEL);
+		u->durb[0].urb.transfer_buffer_length = bufsz;
+		if (u->durb[1].urb.transfer_buffer)
+			kfree(u->durb[1].urb.transfer_buffer);
+		u->durb[1].urb.transfer_buffer = kmalloc(bufsz, GFP_KERNEL);
+		u->durb[1].urb.transfer_buffer_length = bufsz;
+		if (u->syncpipe) {
+			if (u->surb[0].urb.transfer_buffer)
+				kfree(u->surb[0].urb.transfer_buffer);
+			u->surb[0].urb.transfer_buffer = kmalloc(3*SYNCFRAMES, GFP_KERNEL);
+			u->surb[0].urb.transfer_buffer_length = 3*SYNCFRAMES;
+			if (u->surb[1].urb.transfer_buffer)
+				kfree(u->surb[1].urb.transfer_buffer);
+			u->surb[1].urb.transfer_buffer = kmalloc(3*SYNCFRAMES, GFP_KERNEL);
+			u->surb[1].urb.transfer_buffer_length = 3*SYNCFRAMES;
+		}
+		if (!u->durb[0].urb.transfer_buffer || !u->durb[1].urb.transfer_buffer || 
+		    (u->syncpipe && (!u->surb[0].urb.transfer_buffer || !u->surb[1].urb.transfer_buffer))) {
+			printk(KERN_ERR "usbaudio: cannot start playback device %d\n", dev->devnum);
+			return 0;
+		}
+		spin_lock_irqsave(&as->lock, flags);
+	}
+	if (u->dma.count <= 0 && !u->dma.mapped) {
+		spin_unlock_irqrestore(&as->lock, flags);
+		return 0;
+	}
+       	u->flags |= FLG_RUNNING;
+	if (!(u->flags & FLG_URB0RUNNING)) {
+		urb = &u->durb[0].urb;
+		urb->dev = dev;
+		urb->pipe = u->datapipe;
+		urb->transfer_flags = USB_ISO_ASAP;
+		urb->number_of_packets = DESCFRAMES;
+		urb->context = as;
+		urb->complete = usbout_completed;
+		if (!usbout_prepare_desc(u, urb) && !usb_submit_urb(urb))
+			u->flags |= FLG_URB0RUNNING;
+		else
+			u->flags &= ~FLG_RUNNING;
+	}
+	if (u->flags & FLG_RUNNING && !(u->flags & FLG_URB1RUNNING)) {
+		urb = &u->durb[1].urb;
+		urb->dev = dev;
+		urb->pipe = u->datapipe;
+		urb->transfer_flags = USB_ISO_ASAP;
+		urb->number_of_packets = DESCFRAMES;
+		urb->context = as;
+		urb->complete = usbout_completed;
+		if (!usbout_prepare_desc(u, urb) && !usb_submit_urb(urb))
+			u->flags |= FLG_URB1RUNNING;
+		else
+			u->flags &= ~FLG_RUNNING;
+	}
+	if (u->syncpipe) {
+		if (u->flags & FLG_RUNNING && !(u->flags & FLG_SYNC0RUNNING)) {
+			urb = &u->surb[0].urb;
+			urb->dev = dev;
+			urb->pipe = u->syncpipe;
+			urb->transfer_flags = USB_ISO_ASAP;
+			urb->number_of_packets = SYNCFRAMES;
+			urb->context = as;
+			urb->complete = usbout_sync_completed;
+			/* stride: u->syncinterval */
+			if (!usbout_sync_prepare_desc(u, urb) && !usb_submit_urb(urb))
+				u->flags |= FLG_SYNC0RUNNING;
+			else
+				u->flags &= ~FLG_RUNNING;
+		}
+		if (u->flags & FLG_RUNNING && !(u->flags & FLG_SYNC1RUNNING)) {
+			urb = &u->surb[1].urb;
+			urb->dev = dev;
+			urb->pipe = u->syncpipe;
+			urb->transfer_flags = USB_ISO_ASAP;
+			urb->number_of_packets = SYNCFRAMES;
+			urb->context = as;
+			urb->complete = usbout_sync_completed;
+			/* stride: u->syncinterval */
+			if (!usbout_sync_prepare_desc(u, urb) && !usb_submit_urb(urb))
+				u->flags |= FLG_SYNC1RUNNING;
+			else
+				u->flags &= ~FLG_RUNNING;
+		}
+	}
+	spin_unlock_irqrestore(&as->lock, flags);
+	return 0;
+}
+
+/* --------------------------------------------------------------------- */
+
+static unsigned int format_goodness(struct audioformat *afp, unsigned int fmt, unsigned int srate)
+{
+	unsigned int g = 0;
+
+	if (srate < afp->sratelo)
+		g += afp->sratelo - srate;
+	if (srate > afp->sratehi)
+		g += srate - afp->sratehi;
+	if (AFMT_ISSTEREO(afp->format) && !AFMT_ISSTEREO(fmt))
+		g += 0x100000;
+	if (!AFMT_ISSTEREO(afp->format) && AFMT_ISSTEREO(fmt))
+		g += 0x400000;
+	if (AFMT_IS16BIT(afp->format) && !AFMT_IS16BIT(fmt))
+		g += 0x100000;
+	if (!AFMT_IS16BIT(afp->format) && AFMT_IS16BIT(fmt))
+		g += 0x400000;
+	return g;
+}
+
+static int find_format(struct audioformat *afp, unsigned int nr, unsigned int fmt, unsigned int srate)
+{
+	unsigned int i, g, gb = ~0;
+	int j = -1; /* default to failure */
+
+	/* find "best" format (according to format_goodness) */
+	for (i = 0; i < nr; i++) {
+		g = format_goodness(&afp[i], fmt, srate);
+		if (g >= gb) 
+			continue;
+		j = i;
+		gb = g;
+	}
+       	return j;
+}
+
+static int set_format_in(struct usb_audiodev *as)
+{
+	struct usb_device *dev = as->state->usbdev;
+	struct usb_config_descriptor *config = dev->actconfig;
+	struct usb_interface_descriptor *alts;
+	struct usb_interface *iface;
+	struct usbin *u = &as->usbin;
+	struct dmabuf *d = &u->dma;
+	struct audioformat *fmt;
+	unsigned int ep;
+	unsigned char data[3];
+	int fmtnr, ret;
+
+	if (u->interface < 0 || u->interface >= config->bNumInterfaces)
+		return 0;
+	iface = &config->interface[u->interface];
+
+	fmtnr = find_format(as->fmtin, as->numfmtin, d->format, d->srate);
+	if (fmtnr < 0) {
+		printk(KERN_ERR "usbaudio: set_format_in(): failed to find desired format/speed combination.\n");
+		return -1;
+	}
+
+	fmt = as->fmtin + fmtnr;
+	alts = &iface->altsetting[fmt->altsetting];
+	u->format = fmt->format;
+	u->datapipe = usb_rcvisocpipe(dev, alts->endpoint[0].bEndpointAddress & 0xf);
+	u->syncpipe = u->syncinterval = 0;
+	if ((alts->endpoint[0].bmAttributes & 0x0c) == 0x08) {
+		if (alts->bNumEndpoints < 2 ||
+		    alts->endpoint[1].bmAttributes != 0x01 ||
+		    alts->endpoint[1].bSynchAddress != 0 ||
+		    alts->endpoint[1].bEndpointAddress != (alts->endpoint[0].bSynchAddress & 0x7f)) {
+			printk(KERN_ERR "usbaudio: device %d interface %d altsetting %d invalid synch pipe\n",
+			       dev->devnum, u->interface, fmt->altsetting);
+			return -1;
+		}
+		u->syncpipe = usb_sndisocpipe(dev, alts->endpoint[1].bEndpointAddress & 0xf);
+		u->syncinterval = alts->endpoint[1].bRefresh;
+	}
+	if (d->srate < fmt->sratelo)
+		d->srate = fmt->sratelo;
+	if (d->srate > fmt->sratehi)
+		d->srate = fmt->sratehi;
+	dprintk((KERN_DEBUG "usb_audio: set_format_in: usb_set_interface %u %u\n", alts->bInterfaceNumber, fmt->altsetting));
+	
+	if (usb_set_interface(dev, alts->bInterfaceNumber, fmt->altsetting) < 0) {
+		printk(KERN_WARNING "usbaudio: usb_set_interface failed, device %d interface %d altsetting %d\n",
+		       dev->devnum, u->interface, fmt->altsetting);
+		return -1;
+	}
+	if (fmt->sratelo == fmt->sratehi)
+		return 0;
+	ep = usb_pipeendpoint(u->datapipe) | (u->datapipe & USB_DIR_IN);
+	/* if endpoint has pitch control, enable it */
+	if (fmt->attributes & 0x02) {
+		data[0] = 1;
+		if ((ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), SET_CUR, USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT, 
+					   PITCH_CONTROL << 8, ep, data, 1, HZ)) < 0) {
+			printk(KERN_ERR "usbaudio: failure (error %d) to set output pitch control device %d interface %u endpoint 0x%x to %u\n",
+			       ret, dev->devnum, u->interface, ep, d->srate);
+			return -1;
+		}
+	}
+	/* if endpoint has sampling rate control, set it */
+	if (fmt->attributes & 0x01) {
+		data[0] = d->srate;
+		data[1] = d->srate >> 8;
+		data[2] = d->srate >> 16;
+		if ((ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), SET_CUR, USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT, 
+					   SAMPLING_FREQ_CONTROL << 8, ep, data, 3, HZ)) < 0) {
+			printk(KERN_ERR "usbaudio: failure (error %d) to set input sampling frequency device %d interface %u endpoint 0x%x to %u\n",
+			       ret, dev->devnum, u->interface, ep, d->srate);
+			return -1;
+		}
+		if ((ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_CUR, USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_IN,
+					   SAMPLING_FREQ_CONTROL << 8, ep, data, 3, HZ)) < 0) {
+			printk(KERN_ERR "usbaudio: failure (error %d) to get input sampling frequency device %d interface %u endpoint 0x%x\n",
+			       ret, dev->devnum, u->interface, ep);
+			return -1;
+		}
+		dprintk((KERN_DEBUG "usbaudio: set_format_in: device %d interface %d altsetting %d srate req: %u real %u\n",
+		       dev->devnum, u->interface, fmt->altsetting, d->srate, data[0] | (data[1] << 8) | (data[2] << 16)));
+		d->srate = data[0] | (data[1] << 8) | (data[2] << 16);
+	}
+	dprintk((KERN_DEBUG "usbaudio: set_format_in: USB format 0x%x, DMA format 0x%x srate %u\n", u->format, d->format, d->srate));
+	return 0;
+}
+
+static int set_format_out(struct usb_audiodev *as)
+{
+	struct usb_device *dev = as->state->usbdev;
+	struct usb_config_descriptor *config = dev->actconfig;
+	struct usb_interface_descriptor *alts;
+	struct usb_interface *iface;	
+	struct usbout *u = &as->usbout;
+	struct dmabuf *d = &u->dma;
+	struct audioformat *fmt;
+	unsigned int ep;
+	unsigned char data[3];
+	int fmtnr, ret;
+
+	if (u->interface < 0 || u->interface >= config->bNumInterfaces)
+		return 0;
+	iface = &config->interface[u->interface];
+
+	fmtnr = find_format(as->fmtout, as->numfmtout, d->format, d->srate);
+	if (fmtnr < 0) {
+		printk(KERN_ERR "usbaudio: set_format_out(): failed to find desired format/speed combination.\n");
+		return -1;
+	}
+
+	fmt = as->fmtout + fmtnr;
+	u->format = fmt->format;
+	alts = &iface->altsetting[fmt->altsetting];
+	u->datapipe = usb_sndisocpipe(dev, alts->endpoint[0].bEndpointAddress & 0xf);
+	u->syncpipe = u->syncinterval = 0;
+	if ((alts->endpoint[0].bmAttributes & 0x0c) == 0x04) {
+#if 0
+		printk(KERN_DEBUG "bNumEndpoints 0x%02x endpoint[1].bmAttributes 0x%02x\n"
+		       KERN_DEBUG "endpoint[1].bSynchAddress 0x%02x endpoint[1].bEndpointAddress 0x%02x\n"
+		       KERN_DEBUG "endpoint[0].bSynchAddress 0x%02x\n", alts->bNumEndpoints,
+		       alts->endpoint[1].bmAttributes, alts->endpoint[1].bSynchAddress,
+		       alts->endpoint[1].bEndpointAddress, alts->endpoint[0].bSynchAddress);
+#endif
+		if (alts->bNumEndpoints < 2 ||
+		    alts->endpoint[1].bmAttributes != 0x01 ||
+		    alts->endpoint[1].bSynchAddress != 0 ||
+		    alts->endpoint[1].bEndpointAddress != (alts->endpoint[0].bSynchAddress | 0x80)) {
+			printk(KERN_ERR "usbaudio: device %d interface %d altsetting %d invalid synch pipe\n",
+			       dev->devnum, u->interface, fmt->altsetting);
+			return -1;
+		}
+		u->syncpipe = usb_rcvisocpipe(dev, alts->endpoint[1].bEndpointAddress & 0xf);
+		u->syncinterval = alts->endpoint[1].bRefresh;
+	}
+	if (d->srate < fmt->sratelo)
+		d->srate = fmt->sratelo;
+	if (d->srate > fmt->sratehi)
+		d->srate = fmt->sratehi;
+	
+	dprintk((KERN_DEBUG "usb_audio: set_format_out: usb_set_interface %u %u\n", alts->bInterfaceNumber, fmt->altsetting));
+
+	if (usb_set_interface(dev, u->interface, fmt->altsetting) < 0) {
+		printk(KERN_WARNING "usbaudio: usb_set_interface failed, device %d interface %d altsetting %d\n",
+		       dev->devnum, u->interface, fmt->altsetting);
+		return -1;
+	}
+	if (fmt->sratelo == fmt->sratehi)
+		return 0;
+	ep = usb_pipeendpoint(u->datapipe) | (u->datapipe & USB_DIR_IN);
+	/* if endpoint has pitch control, enable it */
+	if (fmt->attributes & 0x02) {
+		data[0] = 1;
+		if ((ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), SET_CUR, USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT, 
+					   PITCH_CONTROL << 8, ep, data, 1, HZ)) < 0) {
+			printk(KERN_ERR "usbaudio: failure (error %d) to set output pitch control device %d interface %u endpoint 0x%x to %u\n",
+			       ret, dev->devnum, u->interface, ep, d->srate);
+			return -1;
+		}
+	}
+	/* if endpoint has sampling rate control, set it */
+	if (fmt->attributes & 0x01) {
+		data[0] = d->srate;
+		data[1] = d->srate >> 8;
+		data[2] = d->srate >> 16;
+		if ((ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), SET_CUR, USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT, 
+					   SAMPLING_FREQ_CONTROL << 8, ep, data, 3, HZ)) < 0) {
+			printk(KERN_ERR "usbaudio: failure (error %d) to set output sampling frequency device %d interface %u endpoint 0x%x to %u\n",
+			       ret, dev->devnum, u->interface, ep, d->srate);
+			return -1;
+		}
+		if ((ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_CUR, USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_IN,
+					   SAMPLING_FREQ_CONTROL << 8, ep, data, 3, HZ)) < 0) {
+			printk(KERN_ERR "usbaudio: failure (error %d) to get output sampling frequency device %d interface %u endpoint 0x%x\n",
+			       ret, dev->devnum, u->interface, ep);
+			return -1;
+		}
+		dprintk((KERN_DEBUG "usbaudio: set_format_out: device %d interface %d altsetting %d srate req: %u real %u\n",
+		       dev->devnum, u->interface, fmt->altsetting, d->srate, data[0] | (data[1] << 8) | (data[2] << 16)));
+		d->srate = data[0] | (data[1] << 8) | (data[2] << 16);
+	}
+	dprintk((KERN_DEBUG "usbaudio: set_format_out: USB format 0x%x, DMA format 0x%x srate %u\n", u->format, d->format, d->srate));
+	return 0;
+}
+
+static int set_format(struct usb_audiodev *s, unsigned int fmode, unsigned int fmt, unsigned int srate)
+{
+	int ret1 = 0, ret2 = 0;
+
+	if (!(fmode & (FMODE_READ|FMODE_WRITE)))
+		return -EINVAL;
+	if (fmode & FMODE_READ) {
+		usbin_stop(s);
+		s->usbin.dma.ready = 0;
+		if (fmt == AFMT_QUERY)
+			fmt = s->usbin.dma.format;
+		else
+			s->usbin.dma.format = fmt;
+		if (!srate)
+			srate = s->usbin.dma.srate;
+		else
+			s->usbin.dma.srate = srate;
+	}
+	if (fmode & FMODE_WRITE) {
+		usbout_stop(s);
+		s->usbout.dma.ready = 0;
+		if (fmt == AFMT_QUERY)
+			fmt = s->usbout.dma.format;
+		else
+			s->usbout.dma.format = fmt;
+		if (!srate)
+			srate = s->usbout.dma.srate;
+		else
+			s->usbout.dma.srate = srate;
+	}
+	if (fmode & FMODE_READ)
+		ret1 = set_format_in(s);
+	if (fmode & FMODE_WRITE)
+		ret2 = set_format_out(s);
+	return ret1 ? ret1 : ret2;
+}
+
+/* --------------------------------------------------------------------- */
+
+static int wrmixer(struct usb_mixerdev *ms, unsigned mixch, unsigned value)
+{
+	struct usb_device *dev = ms->state->usbdev;
+	unsigned char data[2];
+	struct mixerchannel *ch;
+	int v1, v2, v3;
+
+	if (mixch >= ms->numch)
+		return -1;
+	ch = &ms->ch[mixch];
+	v3 = ch->maxval - ch->minval;
+	v1 = value & 0xff;
+	v2 = (value >> 8) & 0xff;
+	if (v1 > 100)
+		v1 = 100;
+	if (v2 > 100)
+		v2 = 100;
+	if (!(ch->flags & (MIXFLG_STEREOIN | MIXFLG_STEREOOUT)))
+		v2 = v1;
+	ch->value = v1 | (v2 << 8);
+	v1 = (v1 * v3) / 100 + ch->minval;
+	v2 = (v2 * v3) / 100 + ch->minval;
+	switch (ch->selector) {
+	case 0:  /* mixer unit request */
+		data[0] = v1;
+		data[1] = v1 >> 8;
+		if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0), SET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
+				    (ch->chnum << 8) | 1, ms->iface | (ch->unitid << 8), data, 2, HZ) < 0)
+			goto err;
+		if (!(ch->flags & (MIXFLG_STEREOIN | MIXFLG_STEREOOUT)))
+			return 0;
+		data[0] = v2;
+		data[1] = v2 >> 8;
+		if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0), SET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
+				    ((ch->chnum + !!(ch->flags & MIXFLG_STEREOIN)) << 8) | (1 + !!(ch->flags & MIXFLG_STEREOOUT)),
+				    ms->iface | (ch->unitid << 8), data, 2, HZ) < 0)
+			goto err;
+		return 0;
+
+		/* various feature unit controls */
+	case VOLUME_CONTROL:
+		data[0] = v1;
+		data[1] = v1 >> 8;
+		if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0), SET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
+				    (ch->selector << 8) | ch->chnum, ms->iface | (ch->unitid << 8), data, 2, HZ) < 0)
+			goto err;
+		if (!(ch->flags & (MIXFLG_STEREOIN | MIXFLG_STEREOOUT)))
+			return 0;
+		data[0] = v2;
+		data[1] = v2 >> 8;
+		if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0), SET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
+				    (ch->selector << 8) | (ch->chnum + 1), ms->iface | (ch->unitid << 8), data, 2, HZ) < 0)
+			goto err;
+		return 0;
+                
+	case BASS_CONTROL:
+	case MID_CONTROL:
+	case TREBLE_CONTROL:
+		data[0] = v1 >> 8;
+		if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0), SET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
+				    (ch->selector << 8) | ch->chnum, ms->iface | (ch->unitid << 8), data, 1, HZ) < 0)
+			goto err;
+		if (!(ch->flags & (MIXFLG_STEREOIN | MIXFLG_STEREOOUT)))
+			return 0;
+		data[0] = v2 >> 8;
+		if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0), SET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
+				    (ch->selector << 8) | (ch->chnum + 1), ms->iface | (ch->unitid << 8), data, 1, HZ) < 0)
+			goto err;
+		return 0;
+
+	default:
+		return -1;
+	}
+	return 0;
+
+ err:
+	printk(KERN_ERR "usbaudio: mixer request device %u if %u unit %u ch %u selector %u failed\n", 
+		dev->devnum, ms->iface, ch->unitid, ch->chnum, ch->selector);
+	return -1;
+}
+
+static int get_rec_src(struct usb_mixerdev *ms)
+{
+	struct usb_device *dev = ms->state->usbdev;
+	unsigned int mask = 0, retmask = 0;
+	unsigned int i, j;
+	unsigned char buf;
+	int err = 0;
+
+	for (i = 0; i < ms->numch; i++) {
+		if (!ms->ch[i].slctunitid || (mask & (1 << i)))
+			continue;
+		if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+				    0, ms->iface | (ms->ch[i].slctunitid << 8), &buf, 1, HZ) < 0) {
+			err = -EIO;
+			printk(KERN_ERR "usbaudio: selector read request device %u if %u unit %u failed\n", 
+			       dev->devnum, ms->iface, ms->ch[i].slctunitid & 0xff);
+			continue;
+		}
+		for (j = i; j < ms->numch; j++) {
+			if ((ms->ch[i].slctunitid ^ ms->ch[j].slctunitid) & 0xff)
+				continue;
+			mask |= 1 << j;
+			if (buf == (ms->ch[j].slctunitid >> 8))
+				retmask |= 1 << ms->ch[j].osschannel;
+		}
+	}
+	if (err)
+		return -EIO;
+	return retmask;
+}
+
+static int set_rec_src(struct usb_mixerdev *ms, int srcmask)
+{
+	struct usb_device *dev = ms->state->usbdev;
+	unsigned int mask = 0, smask, bmask;
+	unsigned int i, j;
+	unsigned char buf;
+	int err = 0;
+
+	for (i = 0; i < ms->numch; i++) {
+		if (!ms->ch[i].slctunitid || (mask & (1 << i)))
+			continue;
+		if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+				    0, ms->iface | (ms->ch[i].slctunitid << 8), &buf, 1, HZ) < 0) {
+			err = -EIO;
+			printk(KERN_ERR "usbaudio: selector read request device %u if %u unit %u failed\n", 
+			       dev->devnum, ms->iface, ms->ch[i].slctunitid & 0xff);
+			continue;
+		}
+		/* first generate smask */
+		smask = bmask = 0;
+		for (j = i; j < ms->numch; j++) {
+			if ((ms->ch[i].slctunitid ^ ms->ch[j].slctunitid) & 0xff)
+				continue;
+			smask |= 1 << ms->ch[j].osschannel;
+			if (buf == (ms->ch[j].slctunitid >> 8))
+				bmask |= 1 << ms->ch[j].osschannel;
+			mask |= 1 << j;
+		}
+		/* check for multiple set sources */
+		j = hweight32(srcmask & smask);
+		if (j == 0)
+			continue;
+		if (j > 1)
+			srcmask &= ~bmask;
+		for (j = i; j < ms->numch; j++) {
+			if ((ms->ch[i].slctunitid ^ ms->ch[j].slctunitid) & 0xff)
+				continue;
+			if (!(srcmask & (1 << ms->ch[j].osschannel)))
+				continue;
+			buf = ms->ch[j].slctunitid >> 8;
+			if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0), SET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
+				    0, ms->iface | (ms->ch[j].slctunitid << 8), &buf, 1, HZ) < 0) {
+				err = -EIO;
+				printk(KERN_ERR "usbaudio: selector write request device %u if %u unit %u failed\n", 
+				       dev->devnum, ms->iface, ms->ch[j].slctunitid & 0xff);
+				continue;
+			}
+		}
+	}
+	return err ? -EIO : 0;
+}
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * should be called with open_sem hold, so that no new processes
+ * look at the audio device to be destroyed
+ */
+
+static void release(struct usb_audio_state *s)
+{
+	struct usb_audiodev *as;
+	struct usb_mixerdev *ms;
+
+	s->count--;
+	if (s->count) {
+		up(&open_sem);
+		return;
+	}
+	up(&open_sem);
+	wake_up(&open_wait);
+	while (!list_empty(&s->audiolist)) {
+		as = list_entry(s->audiolist.next, struct usb_audiodev, list);
+		list_del(&as->list);
+		usbin_release(as);
+		usbout_release(as);
+		dmabuf_release(&as->usbin.dma);
+		dmabuf_release(&as->usbout.dma);
+		kfree(as);
+	}
+	while (!list_empty(&s->mixerlist)) {
+		ms = list_entry(s->mixerlist.next, struct usb_mixerdev, list);
+		list_del(&ms->list);
+		kfree(ms);
+	}
+	kfree(s);
+}
+
+extern inline int prog_dmabuf_in(struct usb_audiodev *as)
+{
+	usbin_stop(as);
+	return dmabuf_init(&as->usbin.dma);
+}
+
+extern inline int prog_dmabuf_out(struct usb_audiodev *as)
+{
+	usbout_stop(as);
+	return dmabuf_init(&as->usbout.dma);
+}
+
+/* --------------------------------------------------------------------- */
+
+static loff_t usb_audio_llseek(struct file *file, loff_t offset, int origin)
+{
+	return -ESPIPE;
+}
+
+/* --------------------------------------------------------------------- */
+
+static int usb_audio_open_mixdev(struct inode *inode, struct file *file)
+{
+	int minor = MINOR(inode->i_rdev);
+	struct list_head *devs, *mdevs;
+	struct usb_mixerdev *ms;
+	struct usb_audio_state *s;
+
+	down(&open_sem);
+	for (devs = audiodevs.next; devs != &audiodevs; devs = devs->next) {
+		s = list_entry(devs, struct usb_audio_state, audiodev);
+		for (mdevs = s->mixerlist.next; mdevs != &s->mixerlist; mdevs = mdevs->next) {
+			ms = list_entry(mdevs, struct usb_mixerdev, list);
+			if (ms->dev_mixer == minor)
+				goto mixer_found;
+		}
+	}
+	up(&open_sem);
+	return -ENODEV;
+
+ mixer_found:
+	if (!s->usbdev) {
+		up(&open_sem);
+		return -EIO;
+	}
+	file->private_data = ms;
+	s->count++;
+
+	up(&open_sem);
+	return 0;
+}
+
+static int usb_audio_release_mixdev(struct inode *inode, struct file *file)
+{
+	struct usb_mixerdev *ms = (struct usb_mixerdev *)file->private_data;
+	struct usb_audio_state *s = ms->state;
+
+	down(&open_sem);
+	release(s);
+	return 0;
+}
+
+static int usb_audio_ioctl_mixdev(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
+{
+	struct usb_mixerdev *ms = (struct usb_mixerdev *)file->private_data;
+	int i, j, val;
+
+	if (!ms->state->usbdev)
+		return -ENODEV;
+  
+	if (cmd == SOUND_MIXER_INFO) {
+		mixer_info info;
+		strncpy(info.id, "USB_AUDIO", sizeof(info.id));
+		strncpy(info.name, "USB Audio Class Driver", sizeof(info.name));
+		info.modify_counter = ms->modcnt;
+		if (copy_to_user((void *)arg, &info, sizeof(info)))
+			return -EFAULT;
+		return 0;
+	}
+	if (cmd == SOUND_OLD_MIXER_INFO) {
+		_old_mixer_info info;
+		strncpy(info.id, "USB_AUDIO", sizeof(info.id));
+		strncpy(info.name, "USB Audio Class Driver", sizeof(info.name));
+		if (copy_to_user((void *)arg, &info, sizeof(info)))
+			return -EFAULT;
+		return 0;
+	}
+	if (cmd == OSS_GETVERSION)
+		return put_user(SOUND_VERSION, (int *)arg);
+	if (_IOC_TYPE(cmd) != 'M' || _IOC_SIZE(cmd) != sizeof(int))
+		return -EINVAL;
+	if (_IOC_DIR(cmd) == _IOC_READ) {
+		switch (_IOC_NR(cmd)) {
+		case SOUND_MIXER_RECSRC: /* Arg contains a bit for each recording source */
+			val = get_rec_src(ms);
+			if (val < 0)
+				return val;
+			return put_user(val, (int *)arg);
+
+		case SOUND_MIXER_DEVMASK: /* Arg contains a bit for each supported device */
+			for (val = i = 0; i < ms->numch; i++)
+				val |= 1 << ms->ch[i].osschannel;
+			return put_user(val, (int *)arg);
+
+		case SOUND_MIXER_RECMASK: /* Arg contains a bit for each supported recording source */
+			for (val = i = 0; i < ms->numch; i++)
+				if (ms->ch[i].slctunitid)
+					val |= 1 << ms->ch[i].osschannel;
+			return put_user(val, (int *)arg);
+
+		case SOUND_MIXER_STEREODEVS: /* Mixer channels supporting stereo */
+			for (val = i = 0; i < ms->numch; i++)
+				if (ms->ch[i].flags & (MIXFLG_STEREOIN | MIXFLG_STEREOOUT))
+					val |= 1 << ms->ch[i].osschannel;
+			return put_user(val, (int *)arg);
+			
+		case SOUND_MIXER_CAPS:
+			return put_user(SOUND_CAP_EXCL_INPUT, (int *)arg);
+
+		default:
+			i = _IOC_NR(cmd);
+			if (i >= SOUND_MIXER_NRDEVICES)
+				return -EINVAL;
+			for (j = 0; j < ms->numch; j++) {
+				if (ms->ch[j].osschannel == i) {
+					return put_user(ms->ch[j].value, (int *)arg);
+				}
+			}
+			return -EINVAL;
+		}
+	}
+	if (_IOC_DIR(cmd) != (_IOC_READ|_IOC_WRITE)) 
+		return -EINVAL;
+	ms->modcnt++;
+	switch (_IOC_NR(cmd)) {
+	case SOUND_MIXER_RECSRC: /* Arg contains a bit for each recording source */
+		get_user_ret(val, (int *)arg, -EFAULT);
+		return set_rec_src(ms, val);
+
+	default:
+		i = _IOC_NR(cmd);
+		if (i >= SOUND_MIXER_NRDEVICES)
+			return -EINVAL;
+		for (j = 0; j < ms->numch && ms->ch[j].osschannel != i; j++);
+		if (j >= ms->numch)
+			return -EINVAL;
+		get_user_ret(val, (int *)arg, -EFAULT);
+		if (wrmixer(ms, j, val))
+			return -EIO;
+		return put_user(ms->ch[j].value, (int *)arg);
+	}
+}
+
+static /*const*/ struct file_operations usb_mixer_fops = {
+	llseek:		usb_audio_llseek,
+	ioctl:		usb_audio_ioctl_mixdev,
+	open:		usb_audio_open_mixdev,
+	release:	usb_audio_release_mixdev,
+};
+
+/* --------------------------------------------------------------------- */
+
+static int drain_out(struct usb_audiodev *as, int nonblock)
+{
+	DECLARE_WAITQUEUE(wait, current);
+	unsigned long flags;
+	int count, tmo;
+	
+	if (as->usbout.dma.mapped || !as->usbout.dma.ready)
+		return 0;
+	usbout_start(as);
+	add_wait_queue(&as->usbout.dma.wait, &wait);
+	for (;;) {
+		__set_current_state(TASK_INTERRUPTIBLE);
+		spin_lock_irqsave(&as->lock, flags);
+		count = as->usbout.dma.count;
+		spin_unlock_irqrestore(&as->lock, flags);
+		if (count <= 0)
+			break;
+		if (signal_pending(current))
+			break;
+		if (nonblock) {
+			remove_wait_queue(&as->usbout.dma.wait, &wait);
+			set_current_state(TASK_RUNNING);
+			return -EBUSY;
+		}
+		tmo = 3 * HZ * count / as->usbout.dma.srate;
+		tmo >>= AFMT_BYTESSHIFT(as->usbout.dma.format);
+		if (!schedule_timeout(tmo + 1)) {
+			printk(KERN_DEBUG "usbaudio: dma timed out??\n");
+			break;
+		}
+	}
+	remove_wait_queue(&as->usbout.dma.wait, &wait);
+	set_current_state(TASK_RUNNING);
+	if (signal_pending(current))
+		return -ERESTARTSYS;
+	return 0;
+}
+
+/* --------------------------------------------------------------------- */
+
+static ssize_t usb_audio_read(struct file *file, char *buffer, size_t count, loff_t *ppos)
+{
+	struct usb_audiodev *as = (struct usb_audiodev *)file->private_data;
+	DECLARE_WAITQUEUE(wait, current);
+	ssize_t ret = 0;
+	unsigned long flags;
+	unsigned int ptr;
+	int cnt, err;
+
+	if (ppos != &file->f_pos)
+		return -ESPIPE;
+	if (as->usbin.dma.mapped)
+		return -ENXIO;
+	if (!as->usbin.dma.ready && (ret = prog_dmabuf_in(as)))
+		return ret;
+	if (!access_ok(VERIFY_WRITE, buffer, count))
+		return -EFAULT;
+	add_wait_queue(&as->usbin.dma.wait, &wait);
+	while (count > 0) {
+		spin_lock_irqsave(&as->lock, flags);
+		ptr = as->usbin.dma.rdptr;
+		cnt = as->usbin.dma.count;
+		/* set task state early to avoid wakeup races */
+		if (cnt <= 0)
+			__set_current_state(TASK_INTERRUPTIBLE);
+		spin_unlock_irqrestore(&as->lock, flags);
+		if (cnt > count)
+			cnt = count;
+		if (cnt <= 0) {
+			if (usbin_start(as)) {
+				if (!ret)
+					ret = -ENODEV;
+				break;
+			}
+			if (file->f_flags & O_NONBLOCK) {
+				if (!ret)
+					ret = -EAGAIN;
+				break;
+			}
+			schedule();
+			if (signal_pending(current)) {
+				if (!ret)
+					ret = -ERESTARTSYS;
+				break;
+			}
+			continue;
+		}
+		if ((err = dmabuf_copyout_user(&as->usbin.dma, ptr, buffer, cnt))) {
+			if (!ret)
+				ret = err;
+			break;
+		}
+		ptr += cnt;
+		if (ptr >= as->usbin.dma.dmasize)
+			ptr -= as->usbin.dma.dmasize;
+		spin_lock_irqsave(&as->lock, flags);
+		as->usbin.dma.rdptr = ptr;
+		as->usbin.dma.count -= cnt;
+		spin_unlock_irqrestore(&as->lock, flags);
+		count -= cnt;
+		buffer += cnt;
+		ret += cnt;
+	}
+	__set_current_state(TASK_RUNNING);
+	remove_wait_queue(&as->usbin.dma.wait, &wait);
+	return ret;
+}
+
+static ssize_t usb_audio_write(struct file *file, const char *buffer, size_t count, loff_t *ppos)
+{
+	struct usb_audiodev *as = (struct usb_audiodev *)file->private_data;
+	DECLARE_WAITQUEUE(wait, current);
+	ssize_t ret = 0;
+	unsigned long flags;
+	unsigned int ptr;
+	unsigned int start_thr;
+	int cnt, err;
+
+	if (ppos != &file->f_pos)
+		return -ESPIPE;
+	if (as->usbout.dma.mapped)
+		return -ENXIO;
+	if (!as->usbout.dma.ready && (ret = prog_dmabuf_out(as)))
+		return ret;
+	if (!access_ok(VERIFY_READ, buffer, count))
+		return -EFAULT;
+	start_thr = (as->usbout.dma.srate << AFMT_BYTESSHIFT(as->usbout.dma.format)) / (1000 / (3 * DESCFRAMES));
+	add_wait_queue(&as->usbout.dma.wait, &wait);
+	while (count > 0) {
+#if 0
+		printk(KERN_DEBUG "usb_audio_write: count %u dma: count %u rdptr %u wrptr %u dmasize %u fragsize %u flags 0x%02x taskst 0x%lx\n",
+		       count, as->usbout.dma.count, as->usbout.dma.rdptr, as->usbout.dma.wrptr, as->usbout.dma.dmasize, as->usbout.dma.fragsize,
+		       as->usbout.flags, current->state);
+#endif
+		spin_lock_irqsave(&as->lock, flags);
+		if (as->usbout.dma.count < 0) {
+			as->usbout.dma.count = 0;
+			as->usbout.dma.rdptr = as->usbout.dma.wrptr;
+		}
+		ptr = as->usbout.dma.wrptr;
+		cnt = as->usbout.dma.dmasize - as->usbout.dma.count;
+		/* set task state early to avoid wakeup races */
+		if (cnt <= 0)
+			__set_current_state(TASK_INTERRUPTIBLE);
+		spin_unlock_irqrestore(&as->lock, flags);
+		if (cnt > count)
+			cnt = count;
+		if (cnt <= 0) {
+			if (usbout_start(as)) {
+				if (!ret)
+					ret = -ENODEV;
+				break;
+			}
+			if (file->f_flags & O_NONBLOCK) {
+				if (!ret)
+					ret = -EAGAIN;
+				break;
+			}
+			schedule();
+			if (signal_pending(current)) {
+				if (!ret)
+					ret = -ERESTARTSYS;
+				break;
+			}
+			continue;
+		}
+		if ((err = dmabuf_copyin_user(&as->usbout.dma, ptr, buffer, cnt))) {
+			if (!ret)
+				ret = err;
+			break;
+		}
+		ptr += cnt;
+		if (ptr >= as->usbout.dma.dmasize)
+			ptr -= as->usbout.dma.dmasize;
+		spin_lock_irqsave(&as->lock, flags);
+		as->usbout.dma.wrptr = ptr;
+		as->usbout.dma.count += cnt;
+		spin_unlock_irqrestore(&as->lock, flags);
+		count -= cnt;
+		buffer += cnt;
+		ret += cnt;
+		if (as->usbout.dma.count >= start_thr && usbout_start(as)) {
+			if (!ret)
+				ret = -ENODEV;
+			break;
+		}
+	}
+	__set_current_state(TASK_RUNNING);
+	remove_wait_queue(&as->usbout.dma.wait, &wait);
+	return ret;
+}
+
+/* Called without the kernel lock - fine */
+static unsigned int usb_audio_poll(struct file *file, struct poll_table_struct *wait)
+{
+	struct usb_audiodev *as = (struct usb_audiodev *)file->private_data;
+	unsigned long flags;
+	unsigned int mask = 0;
+
+	if (file->f_mode & FMODE_WRITE) {
+		if (!as->usbout.dma.ready)
+			prog_dmabuf_out(as);
+		poll_wait(file, &as->usbout.dma.wait, wait);
+	}
+	if (file->f_mode & FMODE_READ) {
+		if (!as->usbin.dma.ready)
+			prog_dmabuf_in(as);
+		poll_wait(file, &as->usbin.dma.wait, wait);
+	}
+	spin_lock_irqsave(&as->lock, flags);
+	if (file->f_mode & FMODE_READ) {
+		if (as->usbin.dma.count >= (signed)as->usbin.dma.fragsize)
+			mask |= POLLIN | POLLRDNORM;
+	}
+	if (file->f_mode & FMODE_WRITE) {
+		if (as->usbout.dma.mapped) {
+			if (as->usbout.dma.count >= (signed)as->usbout.dma.fragsize) 
+				mask |= POLLOUT | POLLWRNORM;
+		} else {
+			if ((signed)as->usbout.dma.dmasize >= as->usbout.dma.count + (signed)as->usbout.dma.fragsize)
+				mask |= POLLOUT | POLLWRNORM;
+		}
+	}
+	spin_unlock_irqrestore(&as->lock, flags);
+	return mask;
+}
+
+static int usb_audio_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct usb_audiodev *as = (struct usb_audiodev *)file->private_data;
+	struct dmabuf *db;
+	int ret;
+
+	if (vma->vm_flags & VM_WRITE) {
+		if ((ret = prog_dmabuf_out(as)) != 0)
+			return ret;
+		db = &as->usbout.dma;
+	} else if (vma->vm_flags & VM_READ) {
+		if ((ret = prog_dmabuf_in(as)) != 0)
+			return ret;
+		db = &as->usbin.dma;
+	} else
+		return -EINVAL;
+
+	return dmabuf_mmap(db,  vma->vm_start, vma->vm_end - vma->vm_start, vma->vm_page_prot);
+}
+
+static int usb_audio_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
+{
+	struct usb_audiodev *as = (struct usb_audiodev *)file->private_data;
+	struct usb_audio_state *s = as->state;
+	unsigned long flags;
+	audio_buf_info abinfo;
+	count_info cinfo;
+	int val, val2, mapped, ret;
+
+	if (!s->usbdev)
+		return -EIO;
+	mapped = ((file->f_mode & FMODE_WRITE) && as->usbout.dma.mapped) ||
+		((file->f_mode & FMODE_READ) && as->usbin.dma.mapped);
+	switch (cmd) {
+	case OSS_GETVERSION:
+		return put_user(SOUND_VERSION, (int *)arg);
+
+	case SNDCTL_DSP_SYNC:
+		if (file->f_mode & FMODE_WRITE)
+			return drain_out(as, 0/*file->f_flags & O_NONBLOCK*/);
+		return 0;
+
+	case SNDCTL_DSP_SETDUPLEX:
+		return 0;
+
+	case SNDCTL_DSP_GETCAPS:
+		return put_user(DSP_CAP_DUPLEX | DSP_CAP_REALTIME | DSP_CAP_TRIGGER | 
+				DSP_CAP_MMAP | DSP_CAP_BATCH, (int *)arg);
+
+	case SNDCTL_DSP_RESET:
+		if (file->f_mode & FMODE_WRITE) {
+			usbout_stop(as);
+			as->usbout.dma.rdptr = as->usbout.dma.wrptr = as->usbout.dma.count = as->usbout.dma.total_bytes = 0;
+		}
+		if (file->f_mode & FMODE_READ) {
+			usbin_stop(as);
+			as->usbin.dma.rdptr = as->usbin.dma.wrptr = as->usbin.dma.count = as->usbin.dma.total_bytes = 0;
+		}
+		return 0;
+
+	case SNDCTL_DSP_SPEED:
+		get_user_ret(val, (int *)arg, -EFAULT);
+		if (val >= 0) {
+			if (val < 4000)
+				val = 4000;
+			if (val > 100000)
+				val = 100000;
+			if (set_format(as, file->f_mode, AFMT_QUERY, val))
+				return -EIO;
+		}
+		return put_user((file->f_mode & FMODE_READ) ? as->usbin.dma.srate : as->usbout.dma.srate, (int *)arg);
+
+	case SNDCTL_DSP_STEREO:
+		val2 = (file->f_mode & FMODE_READ) ? as->usbin.dma.format : as->usbout.dma.format;
+		if (set_format(as, file->f_mode, val2 | AFMT_STEREO, 0))
+			return -EIO;
+		return 0;
+
+	case SNDCTL_DSP_CHANNELS:
+		get_user_ret(val, (int *)arg, -EFAULT);
+		if (val != 0) {
+			val2 = (file->f_mode & FMODE_READ) ? as->usbin.dma.format : as->usbout.dma.format;
+			if (val == 1)
+				val2 &= ~AFMT_STEREO;
+			else
+				val2 |= AFMT_STEREO;
+			if (set_format(as, file->f_mode, val2, 0))
+				return -EIO;
+		}
+		val2 = (file->f_mode & FMODE_READ) ? as->usbin.dma.format : as->usbout.dma.format;
+		return put_user(AFMT_ISSTEREO(val2) ? 2 : 1, (int *)arg);
+
+	case SNDCTL_DSP_GETFMTS: /* Returns a mask */
+		return put_user(AFMT_U8 | AFMT_U16_LE | AFMT_U16_BE |
+				AFMT_S8 | AFMT_S16_LE | AFMT_S16_BE, (int *)arg);
+
+	case SNDCTL_DSP_SETFMT: /* Selects ONE fmt*/
+		get_user_ret(val, (int *)arg, -EFAULT);
+		if (val != AFMT_QUERY) {
+			if (hweight32(val) != 1)
+				return -EINVAL;
+			if (!(val & (AFMT_U8 | AFMT_U16_LE | AFMT_U16_BE |
+				     AFMT_S8 | AFMT_S16_LE | AFMT_S16_BE)))
+				return -EINVAL;
+			val2 = (file->f_mode & FMODE_READ) ? as->usbin.dma.format : as->usbout.dma.format;
+			val |= val2 & AFMT_STEREO;
+			if (set_format(as, file->f_mode, val, 0))
+				return -EIO;
+		}
+		val2 = (file->f_mode & FMODE_READ) ? as->usbin.dma.format : as->usbout.dma.format;
+		return put_user(val2 & ~AFMT_STEREO, (int *)arg);
+
+	case SNDCTL_DSP_POST:
+		return 0;
+
+	case SNDCTL_DSP_GETTRIGGER:
+		val = 0;
+		if (file->f_mode & FMODE_READ && as->usbin.flags & FLG_RUNNING) 
+			val |= PCM_ENABLE_INPUT;
+		if (file->f_mode & FMODE_WRITE && as->usbout.flags & FLG_RUNNING) 
+			val |= PCM_ENABLE_OUTPUT;
+		return put_user(val, (int *)arg);
+
+	case SNDCTL_DSP_SETTRIGGER:
+		get_user_ret(val, (int *)arg, -EFAULT);
+		if (file->f_mode & FMODE_READ) {
+			if (val & PCM_ENABLE_INPUT) {
+				if (!as->usbin.dma.ready && (ret = prog_dmabuf_in(as)))
+					return ret;
+				if (usbin_start(as))
+					return -ENODEV;
+			} else
+				usbin_stop(as);
+		}
+		if (file->f_mode & FMODE_WRITE) {
+			if (val & PCM_ENABLE_OUTPUT) {
+				if (!as->usbout.dma.ready && (ret = prog_dmabuf_out(as)))
+					return ret;
+				if (usbout_start(as))
+					return -ENODEV;
+			} else
+				usbout_stop(as);
+		}
+		return 0;
+
+	case SNDCTL_DSP_GETOSPACE:
+		if (!(file->f_mode & FMODE_WRITE))
+			return -EINVAL;
+		if (!(as->usbout.flags & FLG_RUNNING) && (val = prog_dmabuf_out(as)) != 0)
+			return val;
+		spin_lock_irqsave(&as->lock, flags);
+		abinfo.fragsize = as->usbout.dma.fragsize;
+		abinfo.bytes = as->usbout.dma.dmasize - as->usbout.dma.count;
+		abinfo.fragstotal = as->usbout.dma.numfrag;
+		abinfo.fragments = abinfo.bytes >> as->usbout.dma.fragshift;      
+		spin_unlock_irqrestore(&as->lock, flags);
+		return copy_to_user((void *)arg, &abinfo, sizeof(abinfo)) ? -EFAULT : 0;
+
+	case SNDCTL_DSP_GETISPACE:
+		if (!(file->f_mode & FMODE_READ))
+			return -EINVAL;
+		if (!(as->usbin.flags & FLG_RUNNING) && (val = prog_dmabuf_in(as)) != 0)
+			return val;
+		spin_lock_irqsave(&as->lock, flags);
+		abinfo.fragsize = as->usbin.dma.fragsize;
+		abinfo.bytes = as->usbin.dma.count;
+		abinfo.fragstotal = as->usbin.dma.numfrag;
+		abinfo.fragments = abinfo.bytes >> as->usbin.dma.fragshift;      
+		spin_unlock_irqrestore(&as->lock, flags);
+		return copy_to_user((void *)arg, &abinfo, sizeof(abinfo)) ? -EFAULT : 0;
+		
+	case SNDCTL_DSP_NONBLOCK:
+		file->f_flags |= O_NONBLOCK;
+		return 0;
+
+	case SNDCTL_DSP_GETODELAY:
+		if (!(file->f_mode & FMODE_WRITE))
+			return -EINVAL;
+		spin_lock_irqsave(&as->lock, flags);
+		val = as->usbout.dma.count;
+		spin_unlock_irqrestore(&as->lock, flags);
+		return put_user(val, (int *)arg);
+
+	case SNDCTL_DSP_GETIPTR:
+		if (!(file->f_mode & FMODE_READ))
+			return -EINVAL;
+		spin_lock_irqsave(&as->lock, flags);
+		cinfo.bytes = as->usbin.dma.total_bytes;
+		cinfo.blocks = as->usbin.dma.count >> as->usbin.dma.fragshift;
+		cinfo.ptr = as->usbin.dma.wrptr;
+		if (as->usbin.dma.mapped)
+			as->usbin.dma.count &= as->usbin.dma.fragsize-1;
+		spin_unlock_irqrestore(&as->lock, flags);
+		return copy_to_user((void *)arg, &cinfo, sizeof(cinfo));
+
+	case SNDCTL_DSP_GETOPTR:
+		if (!(file->f_mode & FMODE_WRITE))
+			return -EINVAL;
+		spin_lock_irqsave(&as->lock, flags);
+		cinfo.bytes = as->usbout.dma.total_bytes;
+		cinfo.blocks = as->usbout.dma.count >> as->usbout.dma.fragshift;
+		cinfo.ptr = as->usbout.dma.rdptr;
+		if (as->usbout.dma.mapped)
+			as->usbout.dma.count &= as->usbout.dma.fragsize-1;
+		spin_unlock_irqrestore(&as->lock, flags);
+		return copy_to_user((void *)arg, &cinfo, sizeof(cinfo));
+
+       case SNDCTL_DSP_GETBLKSIZE:
+		if (file->f_mode & FMODE_WRITE) {
+			if ((val = prog_dmabuf_out(as)))
+				return val;
+			return put_user(as->usbout.dma.fragsize, (int *)arg);
+		}
+		if ((val = prog_dmabuf_in(as)))
+			return val;
+		return put_user(as->usbin.dma.fragsize, (int *)arg);
+
+	case SNDCTL_DSP_SETFRAGMENT:
+		get_user_ret(val, (int *)arg, -EFAULT);
+		if (file->f_mode & FMODE_READ) {
+			as->usbin.dma.ossfragshift = val & 0xffff;
+			as->usbin.dma.ossmaxfrags = (val >> 16) & 0xffff;
+			if (as->usbin.dma.ossfragshift < 4)
+				as->usbin.dma.ossfragshift = 4;
+			if (as->usbin.dma.ossfragshift > 15)
+				as->usbin.dma.ossfragshift = 15;
+			if (as->usbin.dma.ossmaxfrags < 4)
+				as->usbin.dma.ossmaxfrags = 4;
+		}
+		if (file->f_mode & FMODE_WRITE) {
+			as->usbout.dma.ossfragshift = val & 0xffff;
+			as->usbout.dma.ossmaxfrags = (val >> 16) & 0xffff;
+			if (as->usbout.dma.ossfragshift < 4)
+				as->usbout.dma.ossfragshift = 4;
+			if (as->usbout.dma.ossfragshift > 15)
+				as->usbout.dma.ossfragshift = 15;
+			if (as->usbout.dma.ossmaxfrags < 4)
+				as->usbout.dma.ossmaxfrags = 4;
+		}
+		return 0;
+
+	case SNDCTL_DSP_SUBDIVIDE:
+		if ((file->f_mode & FMODE_READ && as->usbin.dma.subdivision) ||
+		    (file->f_mode & FMODE_WRITE && as->usbout.dma.subdivision))
+			return -EINVAL;
+		get_user_ret(val, (int *)arg, -EFAULT);
+		if (val != 1 && val != 2 && val != 4)
+			return -EINVAL;
+		if (file->f_mode & FMODE_READ)
+			as->usbin.dma.subdivision = val;
+		if (file->f_mode & FMODE_WRITE)
+			as->usbout.dma.subdivision = val;
+		return 0;
+
+	case SOUND_PCM_READ_RATE:
+		return put_user((file->f_mode & FMODE_READ) ? as->usbin.dma.srate : as->usbout.dma.srate, (int *)arg);
+
+	case SOUND_PCM_READ_CHANNELS:
+		val2 = (file->f_mode & FMODE_READ) ? as->usbin.dma.format : as->usbout.dma.format;
+		return put_user(AFMT_ISSTEREO(val2) ? 2 : 1, (int *)arg);
+
+	case SOUND_PCM_READ_BITS:
+		val2 = (file->f_mode & FMODE_READ) ? as->usbin.dma.format : as->usbout.dma.format;
+		return put_user(AFMT_IS16BIT(val2) ? 16 : 8, (int *)arg);
+
+	case SOUND_PCM_WRITE_FILTER:
+	case SNDCTL_DSP_SETSYNCRO:
+	case SOUND_PCM_READ_FILTER:
+		return -EINVAL;
+	}
+	return -ENOIOCTLCMD;
+}
+
+static int usb_audio_open(struct inode *inode, struct file *file)
+{
+	int minor = MINOR(inode->i_rdev);
+	DECLARE_WAITQUEUE(wait, current);
+	struct list_head *devs, *adevs;
+	struct usb_audiodev *as;
+	struct usb_audio_state *s;
+
+	for (;;) {
+		down(&open_sem);
+		for (devs = audiodevs.next; devs != &audiodevs; devs = devs->next) {
+			s = list_entry(devs, struct usb_audio_state, audiodev);
+			for (adevs = s->audiolist.next; adevs != &s->audiolist; adevs = adevs->next) {
+				as = list_entry(adevs, struct usb_audiodev, list);
+				if (!((as->dev_audio ^ minor) & ~0xf))
+					goto device_found;
+			}
+		}
+		up(&open_sem);
+		return -ENODEV;
+
+	device_found:
+		if (!s->usbdev) {
+			up(&open_sem);
+			return -EIO;
+		}
+		/* wait for device to become free */
+		if (!(as->open_mode & file->f_mode))
+			break;
+		if (file->f_flags & O_NONBLOCK) {
+			up(&open_sem);
+			return -EBUSY;
+		}
+		__set_current_state(TASK_INTERRUPTIBLE);
+		add_wait_queue(&open_wait, &wait);
+		up(&open_sem);
+		schedule();
+		__set_current_state(TASK_RUNNING);
+		remove_wait_queue(&open_wait, &wait);
+		if (signal_pending(current))
+			return -ERESTARTSYS;
+	}
+	if (file->f_mode & FMODE_READ)
+		as->usbin.dma.ossfragshift = as->usbin.dma.ossmaxfrags = as->usbin.dma.subdivision = 0;
+	if (file->f_mode & FMODE_WRITE)
+		as->usbout.dma.ossfragshift = as->usbout.dma.ossmaxfrags = as->usbout.dma.subdivision = 0;
+	if (set_format(as, file->f_mode, ((minor & 0xf) == SND_DEV_DSP16) ? AFMT_S16_LE : AFMT_U8 /* AFMT_ULAW */, 8000)) {
+		up(&open_sem);
+		return -EIO;
+	}
+	file->private_data = as;
+	as->open_mode |= file->f_mode & (FMODE_READ | FMODE_WRITE);
+	s->count++;
+	up(&open_sem);
+	return 0;
+}
+
+static int usb_audio_release(struct inode *inode, struct file *file)
+{
+	struct usb_audiodev *as = (struct usb_audiodev *)file->private_data;
+	struct usb_audio_state *s = as->state;
+	struct usb_device *dev = s->usbdev;
+	struct usb_interface *iface;
+
+	if (file->f_mode & FMODE_WRITE)
+		drain_out(as, file->f_flags & O_NONBLOCK);
+	down(&open_sem);
+	if (file->f_mode & FMODE_WRITE) {
+		usbout_stop(as);
+		if (dev && as->usbout.interface >= 0) {
+			iface = &dev->actconfig->interface[as->usbout.interface];
+			usb_set_interface(dev, iface->altsetting->bInterfaceNumber, 0);
+		}
+		dmabuf_release(&as->usbout.dma);
+		usbout_release(as);
+	}
+	if (file->f_mode & FMODE_READ) {
+		usbin_stop(as);
+		if (dev && as->usbin.interface >= 0) {
+			iface = &dev->actconfig->interface[as->usbin.interface];
+			usb_set_interface(dev, iface->altsetting->bInterfaceNumber, 0);
+		}
+		dmabuf_release(&as->usbin.dma);
+		usbin_release(as);
+	}
+	as->open_mode &= (~file->f_mode) & (FMODE_READ|FMODE_WRITE);
+	release(s);
+	wake_up(&open_wait);
+	return 0;
+}
+
+static /*const*/ struct file_operations usb_audio_fops = {
+	llseek:		usb_audio_llseek,
+	read:		usb_audio_read,
+	write:		usb_audio_write,
+	poll:		usb_audio_poll,
+	ioctl:		usb_audio_ioctl,
+	mmap:		usb_audio_mmap,
+	open:		usb_audio_open,
+	release:	usb_audio_release,
+};
+
+/* --------------------------------------------------------------------- */
+
+static void * usb_audio_probe(struct usb_device *dev, unsigned int ifnum);
+static void usb_audio_disconnect(struct usb_device *dev, void *ptr);
+
+static struct usb_driver usb_audio_driver = {
+	"audio",
+	usb_audio_probe,
+	usb_audio_disconnect,
+	LIST_HEAD_INIT(usb_audio_driver.driver_list), 
+	NULL,
+	0
+};
+
+static void *find_descriptor(void *descstart, unsigned int desclen, void *after, 
+			     u8 dtype, int iface, int altsetting)
+{
+	u8 *p, *end, *next;
+	int ifc = -1, as = -1;
+
+	p = descstart;
+	end = p + desclen;
+	for (; p < end;) {
+		if (p[0] < 2)
+			return NULL;
+		next = p + p[0];
+		if (next > end)
+			return NULL;
+		if (p[1] == USB_DT_INTERFACE) {
+			/* minimum length of interface descriptor */
+			if (p[0] < 9)
+				return NULL;
+			ifc = p[2];
+			as = p[3];
+		}
+		if (p[1] == dtype && (!after || (void *)p > after) &&
+		    (iface == -1 || iface == ifc) && (altsetting == -1 || altsetting == as)) {
+			return p;
+		}
+		p = next;
+	}
+	return NULL;
+}
+
+static void *find_csinterface_descriptor(void *descstart, unsigned int desclen, void *after, u8 dsubtype, int iface, int altsetting)
+{
+	unsigned char *p;
+
+	p = find_descriptor(descstart, desclen, after, USB_DT_CS_INTERFACE, iface, altsetting);
+	while (p) {
+		if (p[0] >= 3 && p[2] == dsubtype)
+			return p;
+		p = find_descriptor(descstart, desclen, p, USB_DT_CS_INTERFACE, iface, altsetting);
+	}
+	return NULL;
+}
+
+static void *find_audiocontrol_unit(void *descstart, unsigned int desclen, void *after, u8 unit, int iface)
+{
+	unsigned char *p;
+
+	p = find_descriptor(descstart, desclen, after, USB_DT_CS_INTERFACE, iface, -1);
+	while (p) {
+		if (p[0] >= 4 && p[2] >= INPUT_TERMINAL && p[2] <= EXTENSION_UNIT && p[3] == unit)
+			return p;
+		p = find_descriptor(descstart, desclen, p, USB_DT_CS_INTERFACE, iface, -1);
+	}
+	return NULL;
+}
+
+static void usb_audio_parsestreaming(struct usb_audio_state *s, unsigned char *buffer, unsigned int buflen, int asifin, int asifout)
+{
+	struct usb_device *dev = s->usbdev;
+	struct usb_audiodev *as;
+	struct usb_config_descriptor *config = dev->actconfig;
+	struct usb_interface_descriptor *alts;
+	struct usb_interface *iface;
+	struct audioformat *fp;
+	unsigned char *fmt, *csep;
+	unsigned int i, j, k, format;
+
+	if (!(as = kmalloc(sizeof(struct usb_audiodev), GFP_KERNEL)))
+		return;
+	memset(as, 0, sizeof(struct usb_audiodev));
+	init_waitqueue_head(&as->usbin.dma.wait);
+	init_waitqueue_head(&as->usbout.dma.wait);
+	spin_lock_init(&as->lock);
+	spin_lock_init(&as->usbin.durb[0].urb.lock);
+	spin_lock_init(&as->usbin.durb[1].urb.lock);
+	spin_lock_init(&as->usbin.surb[0].urb.lock);
+	spin_lock_init(&as->usbin.surb[1].urb.lock);
+	spin_lock_init(&as->usbout.durb[0].urb.lock);
+	spin_lock_init(&as->usbout.durb[1].urb.lock);
+	spin_lock_init(&as->usbout.surb[0].urb.lock);
+	spin_lock_init(&as->usbout.surb[1].urb.lock);
+	as->state = s;
+	as->usbin.interface = asifin;
+	as->usbout.interface = asifout;
+	/* search for input formats */
+	if (asifin >= 0) {
+		as->usbin.flags = FLG_CONNECTED;
+		iface = &config->interface[asifin];
+		for (i = 0; i < iface->num_altsetting; i++) {
+			alts = &iface->altsetting[i];
+			if (alts->bInterfaceClass != USB_CLASS_AUDIO || alts->bInterfaceSubClass != 2)
+				continue;
+			if (alts->bNumEndpoints < 1) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u does not have an endpoint\n", 
+				       dev->devnum, asifin, i);
+				continue;
+			}
+			if ((alts->endpoint[0].bmAttributes & 0x03) != 0x01 ||
+			    !(alts->endpoint[0].bEndpointAddress & 0x80)) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u first endpoint not isochronous in\n", 
+				       dev->devnum, asifin, i);
+				continue;
+			}
+			fmt = find_csinterface_descriptor(buffer, buflen, NULL, AS_GENERAL, asifin, i);
+			if (!fmt) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u FORMAT_TYPE descriptor not found\n", 
+				       dev->devnum, asifin, i);
+				continue;
+			}
+			if (fmt[0] < 7 || fmt[6] != 0 || (fmt[5] != 1 && fmt[5] != 2)) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u format not supported\n", 
+				       dev->devnum, asifin, i);
+				continue;
+			}
+			format = (fmt[5] == 2) ? (AFMT_U16_LE | AFMT_U8) : (AFMT_S16_LE | AFMT_S8);
+			fmt = find_csinterface_descriptor(buffer, buflen, NULL, FORMAT_TYPE, asifin, i);
+			if (!fmt) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u FORMAT_TYPE descriptor not found\n", 
+				       dev->devnum, asifin, i);
+				continue;
+			}
+			if (fmt[0] < 8+3*(fmt[7] ? fmt[7] : 2) || fmt[3] != 1) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u FORMAT_TYPE descriptor not supported\n", 
+				       dev->devnum, asifin, i);
+				continue;
+			}
+			if (fmt[4] < 1 || fmt[4] > 2 || fmt[5] < 1 || fmt[5] > 2) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u unsupported channels %u framesize %u\n", 
+				       dev->devnum, asifin, i, fmt[4], fmt[5]);
+				continue;
+			}
+			csep = find_descriptor(buffer, buflen, NULL, USB_DT_CS_ENDPOINT, asifin, i);
+			if (!csep || csep[0] < 7 || csep[2] != EP_GENERAL) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u no or invalid class specific endpoint descriptor\n", 
+				       dev->devnum, asifin, i);
+				continue;
+			}
+			if (as->numfmtin >= MAXFORMATS)
+				continue;
+			fp = &as->fmtin[as->numfmtin++];
+			if (fmt[5] == 2)
+				format &= (AFMT_U16_LE | AFMT_S16_LE);
+			else
+				format &= (AFMT_U8 | AFMT_S8);
+			if (fmt[4] == 2)
+				format |= AFMT_STEREO;
+			fp->format = format;
+			fp->altsetting = i;
+			fp->sratelo = fp->sratehi = fmt[8] | (fmt[9] << 8) | (fmt[10] << 16);
+			for (j = fmt[7] ? (fmt[7]-1) : 1; j > 0; j--) {
+				k = fmt[8+3*j] | (fmt[9+3*j] << 8) | (fmt[10+3*j] << 16);
+				if (k > fp->sratehi)
+					fp->sratehi = k;
+				if (k < fp->sratelo)
+					fp->sratelo = k;
+			}
+			fp->attributes = csep[3];
+			printk(KERN_INFO "usbaudio: device %u interface %u altsetting %u: format 0x%08x sratelo %u sratehi %u attributes 0x%02x\n", 
+			       dev->devnum, asifin, i, fp->format, fp->sratelo, fp->sratehi, fp->attributes);
+		}
+	}
+	/* search for output formats */
+	if (asifout >= 0) {
+		as->usbout.flags = FLG_CONNECTED;
+		iface = &config->interface[asifout];
+		for (i = 0; i < iface->num_altsetting; i++) {
+			alts = &iface->altsetting[i];
+			if (alts->bInterfaceClass != USB_CLASS_AUDIO || alts->bInterfaceSubClass != 2)
+				continue;
+			if (alts->bNumEndpoints < 1) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u does not have an endpoint\n", 
+				       dev->devnum, asifout, i);
+				continue;
+			}
+			if ((alts->endpoint[0].bmAttributes & 0x03) != 0x01 ||
+			    (alts->endpoint[0].bEndpointAddress & 0x80)) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u first endpoint not isochronous out\n", 
+				       dev->devnum, asifout, i);
+				continue;
+			}
+			fmt = find_csinterface_descriptor(buffer, buflen, NULL, AS_GENERAL, asifout, i);
+			if (!fmt) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u FORMAT_TYPE descriptor not found\n", 
+				       dev->devnum, asifout, i);
+				continue;
+			}
+			if (fmt[0] < 7 || fmt[6] != 0 || (fmt[5] != 1 && fmt[5] != 2)) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u format not supported\n", 
+				       dev->devnum, asifout, i);
+				continue;
+			}
+			format = (fmt[5] == 2) ? (AFMT_U16_LE | AFMT_U8) : (AFMT_S16_LE | AFMT_S8);
+			/* Dallas DS4201 workaround */
+			if (dev->descriptor.idVendor == 0x04fa && dev->descriptor.idProduct == 0x4201)
+				format = (AFMT_S16_LE | AFMT_S8);
+			fmt = find_csinterface_descriptor(buffer, buflen, NULL, FORMAT_TYPE, asifout, i);
+			if (!fmt) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u FORMAT_TYPE descriptor not found\n", 
+				       dev->devnum, asifout, i);
+				continue;
+			}
+			if (fmt[0] < 8+3*(fmt[7] ? fmt[7] : 2) || fmt[3] != 1) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u FORMAT_TYPE descriptor not supported\n", 
+				       dev->devnum, asifout, i);
+				continue;
+			}
+			if (fmt[4] < 1 || fmt[4] > 2 || fmt[5] < 1 || fmt[5] > 2) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u unsupported channels %u framesize %u\n", 
+				       dev->devnum, asifout, i, fmt[4], fmt[5]);
+				continue;
+			}
+			csep = find_descriptor(buffer, buflen, NULL, USB_DT_CS_ENDPOINT, asifout, i);
+			if (!csep || csep[0] < 7 || csep[2] != EP_GENERAL) {
+				printk(KERN_ERR "usbaudio: device %u interface %u altsetting %u no or invalid class specific endpoint descriptor\n", 
+				       dev->devnum, asifout, i);
+				continue;
+			}
+			if (as->numfmtout >= MAXFORMATS)
+				continue;
+			fp = &as->fmtout[as->numfmtout++];
+			if (fmt[5] == 2)
+				format &= (AFMT_U16_LE | AFMT_S16_LE);
+			else
+				format &= (AFMT_U8 | AFMT_S8);
+			if (fmt[4] == 2)
+				format |= AFMT_STEREO;
+			fp->format = format;
+			fp->altsetting = i;
+			fp->sratelo = fp->sratehi = fmt[8] | (fmt[9] << 8) | (fmt[10] << 16);
+			for (j = fmt[7] ? (fmt[7]-1) : 1; j > 0; j--) {
+				k = fmt[8+3*j] | (fmt[9+3*j] << 8) | (fmt[10+3*j] << 16);
+				if (k > fp->sratehi)
+					fp->sratehi = k;
+				if (k < fp->sratelo)
+					fp->sratelo = k;
+			}
+			fp->attributes = csep[3];
+			printk(KERN_INFO "usbaudio: device %u interface %u altsetting %u: format 0x%08x sratelo %u sratehi %u attributes 0x%02x\n", 
+			       dev->devnum, asifout, i, fp->format, fp->sratelo, fp->sratehi, fp->attributes);
+		}
+	}
+	if (as->numfmtin == 0 && as->numfmtout == 0) {
+		kfree(as);
+		return;
+	}
+	if ((as->dev_audio = register_sound_dsp(&usb_audio_fops, -1)) < 0) {
+		printk(KERN_ERR "usbaudio: cannot register dsp\n");
+		kfree(as);
+		return;
+	}
+	/* everything successful */
+	list_add_tail(&as->list, &s->audiolist);
+}
+
+struct consmixstate {
+	struct usb_audio_state *s;
+	unsigned char *buffer;
+	unsigned int buflen;
+	unsigned int ctrlif;
+	struct mixerchannel mixch[SOUND_MIXER_NRDEVICES];
+	unsigned int nrmixch;
+	unsigned int mixchmask;
+	unsigned long unitbitmap[32/sizeof(unsigned long)];
+	/* return values */
+	unsigned int nrchannels;
+	unsigned int termtype;
+	unsigned int chconfig;
+};
+
+static struct mixerchannel *getmixchannel(struct consmixstate *state, unsigned int nr)
+{
+	struct mixerchannel *c;
+
+	if (nr >= SOUND_MIXER_NRDEVICES) {
+		printk(KERN_ERR "usbaudio: invalid OSS mixer channel %u\n", nr);
+		return NULL;
+	}
+	if (!(state->mixchmask & (1 << nr))) {
+		printk(KERN_WARNING "usbaudio: OSS mixer channel %u already in use\n", nr);
+		return NULL;
+	}
+	c = &state->mixch[state->nrmixch++];
+	c->osschannel = nr;
+	state->mixchmask &= ~(1 << nr);
+	return c;
+}
+
+static unsigned int getvolchannel(struct consmixstate *state)
+{
+	unsigned int u;
+
+	if ((state->termtype & 0xff00) == 0x0000 && (state->mixchmask & SOUND_MASK_VOLUME))
+		return SOUND_MIXER_VOLUME;
+	if ((state->termtype & 0xff00) == 0x0100) {
+		if (state->mixchmask & SOUND_MASK_PCM)
+			return SOUND_MIXER_PCM;
+		if (state->mixchmask & SOUND_MASK_ALTPCM)
+			return SOUND_MIXER_ALTPCM;
+	}
+	if ((state->termtype & 0xff00) == 0x0200 && (state->mixchmask & SOUND_MASK_MIC))
+		return SOUND_MIXER_MIC;
+	if ((state->termtype & 0xff00) == 0x0300 && (state->mixchmask & SOUND_MASK_SPEAKER))
+		return SOUND_MIXER_SPEAKER;
+	if ((state->termtype & 0xff00) == 0x0500) {
+		if (state->mixchmask & SOUND_MASK_PHONEIN)
+			return SOUND_MIXER_PHONEIN;
+		if (state->mixchmask & SOUND_MASK_PHONEOUT)
+			return SOUND_MIXER_PHONEOUT;
+	}
+	if (state->termtype >= 0x710 && state->termtype <= 0x711 && (state->mixchmask & SOUND_MASK_RADIO))
+		return SOUND_MIXER_RADIO;
+	if (state->termtype >= 0x709 && state->termtype <= 0x70f && (state->mixchmask & SOUND_MASK_VIDEO))
+		return SOUND_MIXER_VIDEO;
+	u = ffs(state->mixchmask & (SOUND_MASK_LINE | SOUND_MASK_CD | SOUND_MASK_LINE1 | SOUND_MASK_LINE2 | SOUND_MASK_LINE3 |
+				    SOUND_MASK_DIGITAL1 | SOUND_MASK_DIGITAL2 | SOUND_MASK_DIGITAL3));
+	return u-1;
+}
+
+static void prepmixch(struct consmixstate *state)
+{
+	struct usb_device *dev = state->s->usbdev;
+	struct mixerchannel *ch;
+	unsigned char buf[2];
+	__s16 v1;
+	unsigned int v2, v3;
+
+	if (!state->nrmixch || state->nrmixch > SOUND_MIXER_NRDEVICES)
+		return;
+	ch = &state->mixch[state->nrmixch-1];
+	switch (ch->selector) {
+	case 0:  /* mixer unit request */
+		if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_MIN, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+				    (ch->chnum << 8) | 1, state->ctrlif | (ch->unitid << 8), buf, 2, HZ) < 0)
+			goto err;
+		ch->minval = buf[0] | (buf[1] << 8);
+		if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_MAX, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+				    (ch->chnum << 8) | 1, state->ctrlif | (ch->unitid << 8), buf, 2, HZ) < 0)
+			goto err;
+		ch->maxval = buf[0] | (buf[1] << 8);
+		v2 = ch->maxval - ch->minval;
+		if (!v2)
+			v2 = 1;
+		if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+				    (ch->chnum << 8) | 1, state->ctrlif | (ch->unitid << 8), buf, 2, HZ) < 0)
+			goto err;
+		v1 = buf[0] | (buf[1] << 8);
+		v3 = v1 - ch->minval;
+		v3 = 100 * v3 / v2;
+		if (v3 > 100)
+			v3 = 100;
+		ch->value = v3;
+		if (ch->flags & (MIXFLG_STEREOIN | MIXFLG_STEREOOUT)) {
+			if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+					    ((ch->chnum + !!(ch->flags & MIXFLG_STEREOIN)) << 8) | (1 + !!(ch->flags & MIXFLG_STEREOOUT)),
+					    state->ctrlif | (ch->unitid << 8), buf, 2, HZ) < 0)
+			goto err;
+			v1 = buf[0] | (buf[1] << 8);
+			v3 = v1 - ch->minval;
+			v3 = 100 * v3 / v2;
+			if (v3 > 100)
+				v3 = 100;
+		}
+		ch->value |= v3 << 8;
+		break;
+
+		/* various feature unit controls */
+	case VOLUME_CONTROL:
+		if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_MIN, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+				    (ch->selector << 8) | ch->chnum, state->ctrlif | (ch->unitid << 8), buf, 2, HZ) < 0)
+			goto err;
+		ch->minval = buf[0] | (buf[1] << 8);
+		if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_MAX, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+				    (ch->selector << 8) | ch->chnum, state->ctrlif | (ch->unitid << 8), buf, 2, HZ) < 0)
+			goto err;
+		ch->maxval = buf[0] | (buf[1] << 8);
+		if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+				    (ch->selector << 8) | ch->chnum, state->ctrlif | (ch->unitid << 8), buf, 2, HZ) < 0)
+			goto err;
+		v1 = buf[0] | (buf[1] << 8);
+		v2 = ch->maxval - ch->minval;
+		v3 = v1 - ch->minval;
+		if (!v2)
+			v2 = 1;
+		v3 = 100 * v3 / v2;
+		if (v3 > 100)
+			v3 = 100;
+		ch->value = v3;
+		if (ch->flags & (MIXFLG_STEREOIN | MIXFLG_STEREOOUT)) {
+			if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+					    (ch->selector << 8) | (ch->chnum + 1), state->ctrlif | (ch->unitid << 8), buf, 2, HZ) < 0)
+				goto err;
+			v1 = buf[0] | (buf[1] << 8);
+			v3 = v1 - ch->minval;
+			v3 = 100 * v3 / v2;
+			if (v3 > 100)
+				v3 = 100;
+		}
+		ch->value |= v3 << 8;
+		break;
+		
+	case BASS_CONTROL:
+	case MID_CONTROL:
+	case TREBLE_CONTROL:
+		if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_MIN, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+				    (ch->selector << 8) | ch->chnum, state->ctrlif | (ch->unitid << 8), buf, 1, HZ) < 0)
+			goto err;
+		ch->minval = buf[0] << 8;
+		if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_MAX, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+				    (ch->selector << 8) | ch->chnum, state->ctrlif | (ch->unitid << 8), buf, 1, HZ) < 0)
+			goto err;
+		ch->maxval = buf[0] << 8;
+		if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+				    (ch->selector << 8) | ch->chnum, state->ctrlif | (ch->unitid << 8), buf, 1, HZ) < 0)
+			goto err;
+		v1 = buf[0] << 8;
+		v2 = ch->maxval - ch->minval;
+		v3 = v1 - ch->minval;
+		if (!v2)
+			v2 = 1;
+		v3 = 100 * v3 / v2;
+		if (v3 > 100)
+			v3 = 100;
+		ch->value = v3;
+		if (ch->flags & (MIXFLG_STEREOIN | MIXFLG_STEREOOUT)) {
+			if (usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+					    (ch->selector << 8) | (ch->chnum + 1), state->ctrlif | (ch->unitid << 8), buf, 1, HZ) < 0)
+				goto err;
+			v1 = buf[0] << 8;
+			v3 = v1 - ch->minval;
+			v3 = 100 * v3 / v2;
+			if (v3 > 100)
+				v3 = 100;
+		}
+		ch->value |= v3 << 8;
+		break;
+		
+	default:
+		goto err;
+	}
+	return;
+
+ err:
+	printk(KERN_ERR "usbaudio: mixer request device %u if %u unit %u ch %u selector %u failed\n", 
+	       dev->devnum, state->ctrlif, ch->unitid, ch->chnum, ch->selector);
+	if (state->nrmixch)
+		state->nrmixch--;
+}
+
+
+static void usb_audio_recurseunit(struct consmixstate *state, unsigned char unitid);
+
+extern inline int checkmixbmap(unsigned char *bmap, unsigned char flg, unsigned int inidx, unsigned int numoch)
+{
+	unsigned int idx;
+
+	idx = inidx*numoch;
+	if (!(bmap[-(idx >> 3)] & (0x80 >> (idx & 7))))
+		return 0;
+	if (!(flg & (MIXFLG_STEREOIN | MIXFLG_STEREOOUT)))
+		return 1;
+	idx = (inidx+!!(flg & MIXFLG_STEREOIN))*numoch+!!(flg & MIXFLG_STEREOOUT);
+	if (!(bmap[-(idx >> 3)] & (0x80 >> (idx & 7))))
+		return 0;
+	return 1;
+}
+
+static void usb_audio_mixerunit(struct consmixstate *state, unsigned char *mixer)
+{
+	unsigned int nroutch = mixer[5+mixer[4]];
+	unsigned int chidx[SOUND_MIXER_NRDEVICES+1];
+	unsigned int termt[SOUND_MIXER_NRDEVICES];
+	unsigned char flg = (nroutch >= 2) ? MIXFLG_STEREOOUT : 0;
+	unsigned char *bmap = &mixer[9+mixer[4]];
+	unsigned int bmapsize;
+	struct mixerchannel *ch;
+	unsigned int i;
+
+	if (!mixer[4]) {
+		printk(KERN_ERR "usbaudio: unit %u invalid MIXER_UNIT descriptor\n", mixer[3]);
+		return;
+	}
+	if (mixer[4] > SOUND_MIXER_NRDEVICES) {
+		printk(KERN_ERR "usbaudio: mixer unit %u: too many input pins\n", mixer[3]);
+		return;
+	}
+	chidx[0] = 0;
+	for (i = 0; i < mixer[4]; i++) {
+		usb_audio_recurseunit(state, mixer[5+i]);
+		chidx[i+1] = chidx[i] + state->nrchannels;
+		termt[i] = state->termtype;
+	}
+	state->termtype = 0;
+	state->chconfig = mixer[6+mixer[4]] | (mixer[7+mixer[4]] << 8);
+	bmapsize = (nroutch * chidx[mixer[4]] + 7) >> 3;
+	bmap += bmapsize - 1;
+	if (mixer[0] < 10+mixer[4]+bmapsize) {
+		printk(KERN_ERR "usbaudio: unit %u invalid MIXER_UNIT descriptor (bitmap too small)\n", mixer[3]);
+		return;
+	}
+	for (i = 0; i < mixer[4]; i++) {
+		state->termtype = termt[i];
+		if (chidx[i+1]-chidx[i] >= 2) {
+			flg |= MIXFLG_STEREOIN;
+			if (checkmixbmap(bmap, flg, chidx[i], nroutch)) {
+				ch = getmixchannel(state, getvolchannel(state));
+				if (ch) {
+					ch->unitid = mixer[3];
+					ch->selector = 0;
+					ch->chnum = chidx[i]+1;
+					ch->flags = flg;
+					prepmixch(state);
+				}
+				continue;
+			}
+		}
+		flg &= ~MIXFLG_STEREOIN;
+		if (checkmixbmap(bmap, flg, chidx[i], nroutch)) {
+			ch = getmixchannel(state, getvolchannel(state));
+			if (ch) {
+				ch->unitid = mixer[3];
+				ch->selector = 0;
+				ch->chnum = chidx[i]+1;
+				ch->flags = flg;
+				prepmixch(state);
+			}
+		}
+	}	
+	state->termtype = 0;
+}
+
+static struct mixerchannel *slctsrc_findunit(struct consmixstate *state, __u8 unitid)
+{
+	unsigned int i;
+	
+	for (i = 0; i < state->nrmixch; i++)
+		if (state->mixch[i].unitid == unitid)
+			return &state->mixch[i];
+	return NULL;
+}
+
+static void usb_audio_selectorunit(struct consmixstate *state, unsigned char *selector)
+{
+	unsigned int chnum, i, mixch;
+	struct mixerchannel *mch;
+
+	if (!selector[4]) {
+		printk(KERN_ERR "usbaudio: unit %u invalid SELECTOR_UNIT descriptor\n", selector[3]);
+		return;
+	}
+	mixch = state->nrmixch;
+	usb_audio_recurseunit(state, selector[5]);
+	if (state->nrmixch != mixch) {
+		mch = &state->mixch[state->nrmixch-1];
+		mch->slctunitid = selector[3] | (1 << 8);
+	} else if ((mch = slctsrc_findunit(state, selector[5]))) {
+		mch->slctunitid = selector[3] | (1 << 8);
+	} else {
+		printk(KERN_INFO "usbaudio: selector unit %u: ignoring channel 1\n", selector[3]);
+	}
+	chnum = state->nrchannels;
+	for (i = 1; i < selector[4]; i++) {
+		mixch = state->nrmixch;
+		usb_audio_recurseunit(state, selector[5+i]);
+		if (chnum != state->nrchannels) {
+			printk(KERN_ERR "usbaudio: selector unit %u: input pins with varying channel numbers\n", selector[3]);
+			state->termtype = 0;
+			state->chconfig = 0;
+			state->nrchannels = 0;
+			return;
+		}
+		if (state->nrmixch != mixch) {
+			mch = &state->mixch[state->nrmixch-1];
+			mch->slctunitid = selector[3] | ((i + 1) << 8);
+		} else if ((mch = slctsrc_findunit(state, selector[5+i]))) {
+			mch->slctunitid = selector[3] | ((i + 1) << 8);
+		} else {
+			printk(KERN_INFO "usbaudio: selector unit %u: ignoring channel %u\n", selector[3], i+1);
+		}
+	}
+	state->termtype = 0;
+	state->chconfig = 0;
+}
+
+/* in the future we might try to handle 3D etc. effect units */
+
+static void usb_audio_processingunit(struct consmixstate *state, unsigned char *proc)
+{
+	unsigned int i;
+
+	for (i = 0; i < proc[6]; i++)
+		usb_audio_recurseunit(state, proc[7+i]);
+	state->nrchannels = proc[7+proc[6]];
+	state->termtype = 0;
+	state->chconfig = proc[8+proc[6]] | (proc[9+proc[6]] << 8);
+}
+
+static void usb_audio_featureunit(struct consmixstate *state, unsigned char *ftr)
+{
+	struct mixerchannel *ch;
+	unsigned short chftr, mchftr;
+#if 0
+	struct usb_device *dev = state->s->usbdev;
+	unsigned char data[1];
+#endif
+
+	usb_audio_recurseunit(state, ftr[4]);
+	if (state->nrchannels == 0) {
+		printk(KERN_ERR "usbaudio: feature unit %u source has no channels\n", ftr[3]);
+		return;
+	}
+	if (state->nrchannels > 2)
+		printk(KERN_WARNING "usbaudio: feature unit %u: OSS mixer interface does not support more than 2 channels\n", ftr[3]);
+	if (state->nrchannels == 1 && ftr[0] == 7+ftr[5]) {
+		printk(KERN_WARNING "usbaudio: workaround for broken Philips Camera Microphone descriptor enabled\n");
+		mchftr = ftr[6];
+		chftr = 0;
+	} else {
+		if (ftr[0] < 7+ftr[5]*(1+state->nrchannels)) {
+			printk(KERN_ERR "usbaudio: unit %u: invalid FEATURE_UNIT descriptor\n", ftr[3]);
+			return;
+		}
+		mchftr = ftr[6];
+		chftr = ftr[6+ftr[5]];
+		if (state->nrchannels > 1)
+			chftr &= ftr[6+2*ftr[5]];
+	}
+	/* volume control */
+	if (chftr & 2) {
+		ch = getmixchannel(state, getvolchannel(state));
+		if (ch) {
+			ch->unitid = ftr[3];
+			ch->selector = VOLUME_CONTROL;
+			ch->chnum = 1;
+			ch->flags = (state->nrchannels > 1) ? (MIXFLG_STEREOIN | MIXFLG_STEREOOUT) : 0;
+			prepmixch(state);
+		}
+	} else if (mchftr & 2) {
+		ch = getmixchannel(state, getvolchannel(state));
+		if (ch) {
+			ch->unitid = ftr[3];
+			ch->selector = VOLUME_CONTROL;
+			ch->chnum = 0;
+			ch->flags = 0;
+			prepmixch(state);
+		}
+	}
+	/* bass control */
+	if (chftr & 4) {
+		ch = getmixchannel(state, SOUND_MIXER_BASS);
+		if (ch) {
+			ch->unitid = ftr[3];
+			ch->selector = BASS_CONTROL;
+			ch->chnum = 1;
+			ch->flags = (state->nrchannels > 1) ? (MIXFLG_STEREOIN | MIXFLG_STEREOOUT) : 0;
+			prepmixch(state);
+		}
+	} else if (mchftr & 4) {
+		ch = getmixchannel(state, SOUND_MIXER_BASS);
+		if (ch) {
+			ch->unitid = ftr[3];
+			ch->selector = BASS_CONTROL;
+			ch->chnum = 0;
+			ch->flags = 0;
+			prepmixch(state);
+		}
+	}
+	/* treble control */
+	if (chftr & 16) {
+		ch = getmixchannel(state, SOUND_MIXER_TREBLE);
+		if (ch) {
+			ch->unitid = ftr[3];
+			ch->selector = TREBLE_CONTROL;
+			ch->chnum = 1;
+			ch->flags = (state->nrchannels > 1) ? (MIXFLG_STEREOIN | MIXFLG_STEREOOUT) : 0;
+			prepmixch(state);
+		}
+	} else if (mchftr & 16) {
+		ch = getmixchannel(state, SOUND_MIXER_TREBLE);
+		if (ch) {
+			ch->unitid = ftr[3];
+			ch->selector = TREBLE_CONTROL;
+			ch->chnum = 0;
+			ch->flags = 0;
+			prepmixch(state);
+		}
+	}
+#if 0
+	/* if there are mute controls, unmute them */
+	/* does not seem to be necessary, and the Dallas chip does not seem to support the "all" channel (255) */
+	if ((chftr & 1) || (mchftr & 1)) {
+		printk(KERN_DEBUG "usbaudio: unmuting feature unit %u interface %u\n", ftr[3], state->ctrlif);
+		data[0] = 0;
+		if (usb_control_msg(dev, usb_sndctrlpipe(dev, 0), SET_CUR, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
+				    (MUTE_CONTROL << 8) | 0xff, state->ctrlif | (ftr[3] << 8), data, 1, HZ) < 0)
+			printk(KERN_WARNING "usbaudio: failure to unmute feature unit %u interface %u\n", ftr[3], state->ctrlif);
+ 	}
+#endif
+}
+
+static void usb_audio_recurseunit(struct consmixstate *state, unsigned char unitid)
+{
+	unsigned char *p1;
+	unsigned int i, j;
+
+	if (test_and_set_bit(unitid, &state->unitbitmap)) {
+		printk(KERN_INFO "usbaudio: mixer path revisits unit %d\n", unitid);
+		return;
+	}
+	p1 = find_audiocontrol_unit(state->buffer, state->buflen, NULL, unitid, state->ctrlif);
+	if (!p1) {
+		printk(KERN_ERR "usbaudio: unit %d not found!\n", unitid);
+		return;
+	}
+	state->nrchannels = 0;
+	state->termtype = 0;
+	state->chconfig = 0;
+	switch (p1[2]) {
+	case INPUT_TERMINAL:
+		if (p1[0] < 12) {
+			printk(KERN_ERR "usbaudio: unit %u: invalid INPUT_TERMINAL descriptor\n", unitid);
+			return;
+		}
+		state->nrchannels = p1[7];
+		state->termtype = p1[4] | (p1[5] << 8);
+		state->chconfig = p1[8] | (p1[9] << 8);
+		return;
+
+	case MIXER_UNIT:
+		if (p1[0] < 10 || p1[0] < 10+p1[4]) {
+			printk(KERN_ERR "usbaudio: unit %u: invalid MIXER_UNIT descriptor\n", unitid);
+			return;
+		}
+		usb_audio_mixerunit(state, p1);
+		return;
+
+	case SELECTOR_UNIT:
+		if (p1[0] < 6 || p1[0] < 6+p1[4]) {
+			printk(KERN_ERR "usbaudio: unit %u: invalid SELECTOR_UNIT descriptor\n", unitid);
+			return;
+		}
+		usb_audio_selectorunit(state, p1);
+		return;
+
+	case FEATURE_UNIT:
+		if (p1[0] < 7 || p1[0] < 7+p1[5]) {
+			printk(KERN_ERR "usbaudio: unit %u: invalid FEATURE_UNIT descriptor\n", unitid);
+			return;
+		}
+		usb_audio_featureunit(state, p1);
+		return;		
+
+	case PROCESSING_UNIT:
+		if (p1[0] < 13 || p1[0] < 13+p1[6] || p1[0] < 13+p1[6]+p1[11+p1[6]] || p1[0] < 13+p1[6]+p1[11+p1[6]]+p1[13+p1[6]+p1[11+p1[6]]]) {
+			printk(KERN_ERR "usbaudio: unit %u: invalid PROCESSING_UNIT descriptor\n", unitid);
+			return;
+		}
+		usb_audio_processingunit(state, p1);
+		return;		
+
+	case EXTENSION_UNIT:
+		if (p1[0] < 13 || p1[0] < 13+p1[6] || p1[0] < 13+p1[6]+p1[11+p1[6]]) {
+			printk(KERN_ERR "usbaudio: unit %u: invalid EXTENSION_UNIT descriptor\n", unitid);
+			return;
+		}
+		for (j = i = 0; i < p1[6]; i++) {
+			usb_audio_recurseunit(state, p1[7+i]);
+			if (!i)
+				j = state->termtype;
+			else if (j != state->termtype)
+				j = 0;
+		}
+		state->nrchannels = p1[7+p1[6]];
+		state->chconfig = p1[8+p1[6]] | (p1[9+p1[6]] << 8);
+		state->termtype = j;
+		return;
+
+	default:
+		printk(KERN_ERR "usbaudio: unit %u: unexpected type 0x%02x\n", unitid, p1[2]);
+		return;
+	}
+}
+
+static void usb_audio_constructmixer(struct usb_audio_state *s, unsigned char *buffer, unsigned int buflen, unsigned int ctrlif, unsigned char *oterm)
+{
+	struct usb_mixerdev *ms;
+	struct consmixstate state;
+
+	memset(&state, 0, sizeof(state));
+	state.s = s;
+	state.nrmixch = 0;
+	state.mixchmask = ~0;
+	state.buffer = buffer;
+	state.buflen = buflen;
+	state.ctrlif = ctrlif;
+	set_bit(oterm[3], &state.unitbitmap);  /* mark terminal ID as visited */
+	printk(KERN_INFO "usbaudio: constructing mixer for Terminal %u type 0x%04x\n",
+	       oterm[3], oterm[4] | (oterm[5] << 8));
+	usb_audio_recurseunit(&state, oterm[7]);
+	if (!state.nrmixch) {
+		printk(KERN_INFO "usbaudio: no mixer controls found for Terminal %u\n", oterm[3]);
+		return;
+	}
+	if (!(ms = kmalloc(sizeof(struct usb_mixerdev)+state.nrmixch*sizeof(struct mixerchannel), GFP_KERNEL)))
+		return;
+	memset(ms, 0, sizeof(struct usb_mixerdev));
+	memcpy(&ms->ch, &state.mixch, state.nrmixch*sizeof(struct mixerchannel));
+	ms->state = s;
+	ms->iface = ctrlif;
+	ms->numch = state.nrmixch;
+	if ((ms->dev_mixer = register_sound_mixer(&usb_mixer_fops, -1)) < 0) {
+		printk(KERN_ERR "usbaudio: cannot register mixer\n");
+		kfree(ms);
+		return;
+	}
+	list_add_tail(&ms->list, &s->mixerlist);
+}
+
+static void *usb_audio_parsecontrol(struct usb_device *dev, unsigned char *buffer, unsigned int buflen, unsigned int ctrlif)
+{
+	struct usb_audio_state *s;
+	struct usb_config_descriptor *config = dev->actconfig;
+	struct usb_interface *iface;
+	unsigned char ifin[USB_MAXINTERFACES], ifout[USB_MAXINTERFACES];
+	unsigned char *p1;
+	unsigned int i, j, k, numifin = 0, numifout = 0;
+	
+	if (!(s = kmalloc(sizeof(struct usb_audio_state), GFP_KERNEL)))
+		return NULL;
+	memset(s, 0, sizeof(struct usb_audio_state));
+	INIT_LIST_HEAD(&s->audiolist);
+	INIT_LIST_HEAD(&s->mixerlist);
+	s->usbdev = dev;
+	s->count = 1;
+
+	/* find audiocontrol interface */
+	if (!(p1 = find_csinterface_descriptor(buffer, buflen, NULL, HEADER, ctrlif, -1))) {
+		printk(KERN_ERR "usbaudio: device %d audiocontrol interface %u no HEADER found\n",
+		       dev->devnum, ctrlif);
+		goto ret;
+	}
+	if (p1[0] < 8 + p1[7]) {
+		printk(KERN_ERR "usbaudio: device %d audiocontrol interface %u HEADER error\n",
+		       dev->devnum, ctrlif);
+		goto ret;
+	}
+	if (!p1[7])
+		printk(KERN_INFO "usbaudio: device %d audiocontrol interface %u has no AudioStreaming and MidiStreaming interfaces\n",
+		       dev->devnum, ctrlif);
+	for (i = 0; i < p1[7]; i++) {
+		j = p1[8+i];
+		if (j >= config->bNumInterfaces) {
+			printk(KERN_ERR "usbaudio: device %d audiocontrol interface %u interface %u does not exist\n",
+			       dev->devnum, ctrlif, j);
+			continue;
+		}
+		iface = &config->interface[j];
+		if (iface->altsetting[0].bInterfaceClass != USB_CLASS_AUDIO) {
+			printk(KERN_ERR "usbaudio: device %d audiocontrol interface %u interface %u is not an AudioClass interface\n",
+			       dev->devnum, ctrlif, j);
+			continue;
+		}
+		if (iface->altsetting[0].bInterfaceSubClass == 3) {
+			printk(KERN_INFO "usbaudio: device %d audiocontrol interface %u interface %u MIDIStreaming not supported\n",
+			       dev->devnum, ctrlif, j);
+			continue;
+		}
+		if (iface->altsetting[0].bInterfaceSubClass != 2) {
+			printk(KERN_ERR "usbaudio: device %d audiocontrol interface %u interface %u invalid AudioClass subtype\n",
+			       dev->devnum, ctrlif, j);
+			continue;
+		}
+		if (iface->num_altsetting == 0) {
+			printk(KERN_ERR "usbaudio: device %d audiocontrol interface %u has no working interface.\n", dev->devnum, ctrlif);
+			continue;
+		}
+		if (iface->num_altsetting == 1) {
+			printk(KERN_ERR "usbaudio: device %d audiocontrol interface %u has only 1 altsetting.\n", dev->devnum, ctrlif);
+			continue;
+		}
+		if (iface->altsetting[0].bNumEndpoints > 0) {
+			/* Check all endpoints; should they all have a bandwidth of 0 ? */
+			for (k = 0; k < iface->altsetting[0].bNumEndpoints; k++) {
+				if (iface->altsetting[0].endpoint[k].wMaxPacketSize > 0) {
+					printk(KERN_ERR "usbaudio: device %d audiocontrol interface %u endpoint %d does not have 0 bandwidth at alt[0]\n", dev->devnum, ctrlif, k);
+					break;
+				}
+			}
+			if (k < iface->altsetting[0].bNumEndpoints)
+				continue;
+		}
+		if (iface->altsetting[1].bNumEndpoints < 1) {
+			printk(KERN_ERR "usbaudio: device %d audiocontrol interface %u interface %u has no endpoint\n",
+			       dev->devnum, ctrlif, j);
+			continue;
+		}
+		/* note: this requires the data endpoint to be ep0 and the optional sync
+		   ep to be ep1, which seems to be the case */
+		if (iface->altsetting[1].endpoint[0].bEndpointAddress & USB_DIR_IN) {
+			if (numifin < USB_MAXINTERFACES) {
+				ifin[numifin++] = j;
+				usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1);
+			}
+		} else {
+			if (numifout < USB_MAXINTERFACES) {
+				ifout[numifout++] = j;
+				usb_driver_claim_interface(&usb_audio_driver, iface, (void *)-1);
+			}
+		}
+	}
+	printk(KERN_INFO "usbaudio: device %d audiocontrol interface %u has %u input and %u output AudioStreaming interfaces\n",
+	       dev->devnum, ctrlif, numifin, numifout);
+	for (i = 0; i < numifin && i < numifout; i++)
+		usb_audio_parsestreaming(s, buffer, buflen, ifin[i], ifout[i]);
+	for (j = i; j < numifin; j++)
+		usb_audio_parsestreaming(s, buffer, buflen, ifin[i], -1);
+	for (j = i; j < numifout; j++)
+		usb_audio_parsestreaming(s, buffer, buflen, -1, ifout[i]);
+	/* now walk through all OUTPUT_TERMINAL descriptors to search for mixers */
+	p1 = find_csinterface_descriptor(buffer, buflen, NULL, OUTPUT_TERMINAL, ctrlif, -1);
+	while (p1) {
+		if (p1[0] >= 9)
+			usb_audio_constructmixer(s, buffer, buflen, ctrlif, p1);
+		p1 = find_csinterface_descriptor(buffer, buflen, p1, OUTPUT_TERMINAL, ctrlif, -1);
+	}
+
+ret:
+	if (list_empty(&s->audiolist) && list_empty(&s->mixerlist)) {
+		kfree(s);
+		return NULL;
+	}
+	/* everything successful */
+	down(&open_sem);
+	list_add_tail(&s->audiodev, &audiodevs);
+	up(&open_sem);
+	printk(KERN_DEBUG "usb_audio_parsecontrol: usb_audio_state at %p\n", s);
+	return s;
+}
+
+/* we only care for the currently active configuration */
+
+static void *usb_audio_probe(struct usb_device *dev, unsigned int ifnum)
+{
+	struct usb_config_descriptor *config = dev->actconfig;	
+	unsigned char *buffer;
+	unsigned char buf[8];
+	unsigned int i, buflen;
+	int ret;
+
+#if 0
+	printk(KERN_DEBUG "usbaudio: Probing if %i: IC %x, ISC %x\n", ifnum,
+	       config->interface[ifnum].altsetting[0].bInterfaceClass,
+	       config->interface[ifnum].altsetting[0].bInterfaceSubClass);
+#endif
+	if (config->interface[ifnum].altsetting[0].bInterfaceClass != USB_CLASS_AUDIO ||
+	    config->interface[ifnum].altsetting[0].bInterfaceSubClass != 1) {
+#if 0
+		printk(KERN_DEBUG "usbaudio: vendor id 0x%04x, product id 0x%04x contains no AudioControl interface\n",
+		       dev->descriptor.idVendor, dev->descriptor.idProduct);
+#endif
+		return NULL;
+	}
+	/*
+	 * audiocontrol interface found
+	 * find which configuration number is active
+	 */
+	for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
+		if (dev->config+i == config)
+			goto configfound;
+	printk(KERN_ERR "usbaudio: cannot find active configuration number of device %d\n", dev->devnum);
+	return NULL;
+
+ configfound:
+	if (usb_set_configuration(dev, config->bConfigurationValue) < 0) {
+		printk(KERN_ERR "usbaudio: set_configuration failed (ConfigValue 0x%x)\n", config->bConfigurationValue);
+		return NULL;
+	}
+	ret = usb_get_descriptor(dev, USB_DT_CONFIG, i, buf, 8);
+	if (ret<0) {
+		printk(KERN_ERR "usbaudio: cannot get first 8 bytes of config descriptor %d of device %d\n", i, dev->devnum);
+		return NULL;
+	}
+	if (buf[1] != USB_DT_CONFIG || buf[0] < 9) {
+		printk(KERN_ERR "usbaudio: invalid config descriptor %d of device %d\n", i, dev->devnum);
+		return NULL;
+	}
+	buflen = buf[2] | (buf[3] << 8);
+	if (!(buffer = kmalloc(buflen, GFP_KERNEL)))
+		return NULL;
+	ret = usb_get_descriptor(dev, USB_DT_CONFIG, i, buffer, buflen);
+	if (ret < 0) {
+		kfree(buffer);
+		printk(KERN_ERR "usbaudio: cannot get config descriptor %d of device %d\n", i, dev->devnum);
+		return NULL;
+	}
+	return usb_audio_parsecontrol(dev, buffer, buflen, ifnum);
+}
+
+
+/* a revoke facility would make things simpler */
+
+static void usb_audio_disconnect(struct usb_device *dev, void *ptr)
+{
+	struct usb_audio_state *s = (struct usb_audio_state *)ptr;
+	struct list_head *list;
+	struct usb_audiodev *as;
+	struct usb_mixerdev *ms;
+
+	/* we get called with -1 for every audiostreaming interface registered */
+	if (s == (struct usb_audio_state *)-1) {
+		dprintk((KERN_DEBUG "usb_audio_disconnect: called with -1\n"));
+		return;
+	}
+	if (!s->usbdev) {
+		dprintk((KERN_DEBUG "usb_audio_disconnect: already called for %p!\n", s));
+		return;
+	}
+	down(&open_sem);
+	list_del(&s->audiodev);
+	INIT_LIST_HEAD(&s->audiodev);
+	s->usbdev = NULL;
+	/* deregister all audio and mixer devices, so no new processes can open this device */
+	for(list = s->audiolist.next; list != &s->audiolist; list = list->next) {
+		as = list_entry(list, struct usb_audiodev, list);
+		usbin_disc(as);
+		usbout_disc(as);
+		wake_up(&as->usbin.dma.wait);
+		wake_up(&as->usbout.dma.wait);
+		if (as->dev_audio >= 0)
+			unregister_sound_dsp(as->dev_audio);
+		as->dev_audio = -1;
+	}
+	for(list = s->mixerlist.next; list != &s->mixerlist; list = list->next) {
+		ms = list_entry(list, struct usb_mixerdev, list);
+		if (ms->dev_mixer >= 0)
+			unregister_sound_mixer(ms->dev_mixer);
+		ms->dev_mixer = -1;
+	}
+	release(s);
+	wake_up(&open_wait);
+}
+
+int usb_audio_init(void)
+{
+	usb_register(&usb_audio_driver);
+	return 0;
+}
+
+#ifdef MODULE
+int init_module(void)
 {
+	return usb_audio_init();
 }
 
-void usb_audio_endpoint(struct usb_endpoint_descriptor *interface, u8 *data)
+void cleanup_module(void)
 {
+	usb_deregister(&usb_audio_driver);
 }
 
+#endif