summaryrefslogtreecommitdiffstats
path: root/sound/usb/endpoint.c
diff options
context:
space:
mode:
authorDaniel Mack <zonque@gmail.com>2011-09-14 12:46:57 +0200
committerTakashi Iwai <tiwai@suse.de>2011-09-14 17:07:03 +0200
commitc731bc96ad641a5fa3d50a87b474652505507282 (patch)
tree8c08c95bb3a1ab1eccc91a8298d408d8a6de7d64 /sound/usb/endpoint.c
parente8e8babf561c9560f37b9bd80407ebaf90ad2ca4 (diff)
downloadlinux-c731bc96ad641a5fa3d50a87b474652505507282.tar.bz2
ALSA: snd-usb: move code from urb.c to endpoint.c
No code altered at this point, simply preparing for upcoming refactorizations. Signed-off-by: Daniel Mack <zonque@gmail.com> Acked-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/usb/endpoint.c')
-rw-r--r--sound/usb/endpoint.c948
1 files changed, 948 insertions, 0 deletions
diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
index b3ee7cf243df..81c6edecd862 100644
--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -15,3 +15,951 @@
*
*/
+#include <linux/gfp.h>
+#include <linux/init.h>
+#include <linux/usb.h>
+#include <linux/usb/audio.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+
+#include "usbaudio.h"
+#include "helper.h"
+#include "card.h"
+#include "endpoint.h"
+#include "pcm.h"
+
+/*
+ * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
+ * this will overflow at approx 524 kHz
+ */
+static inline unsigned get_usb_full_speed_rate(unsigned int rate)
+{
+ return ((rate << 13) + 62) / 125;
+}
+
+/*
+ * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
+ * this will overflow at approx 4 MHz
+ */
+static inline unsigned get_usb_high_speed_rate(unsigned int rate)
+{
+ return ((rate << 10) + 62) / 125;
+}
+
+/*
+ * unlink active urbs.
+ */
+static int deactivate_urbs(struct snd_usb_substream *subs, int force, int can_sleep)
+{
+ struct snd_usb_audio *chip = subs->stream->chip;
+ unsigned int i;
+ int async;
+
+ subs->running = 0;
+
+ if (!force && subs->stream->chip->shutdown) /* to be sure... */
+ return -EBADFD;
+
+ async = !can_sleep && chip->async_unlink;
+
+ if (!async && in_interrupt())
+ return 0;
+
+ for (i = 0; i < subs->nurbs; i++) {
+ if (test_bit(i, &subs->active_mask)) {
+ if (!test_and_set_bit(i, &subs->unlink_mask)) {
+ struct urb *u = subs->dataurb[i].urb;
+ if (async)
+ usb_unlink_urb(u);
+ else
+ usb_kill_urb(u);
+ }
+ }
+ }
+ if (subs->syncpipe) {
+ for (i = 0; i < SYNC_URBS; i++) {
+ if (test_bit(i+16, &subs->active_mask)) {
+ if (!test_and_set_bit(i+16, &subs->unlink_mask)) {
+ struct urb *u = subs->syncurb[i].urb;
+ if (async)
+ usb_unlink_urb(u);
+ else
+ usb_kill_urb(u);
+ }
+ }
+ }
+ }
+ return 0;
+}
+
+
+/*
+ * release a urb data
+ */
+static void release_urb_ctx(struct snd_urb_ctx *u)
+{
+ if (u->urb) {
+ if (u->buffer_size)
+ usb_free_coherent(u->subs->dev, u->buffer_size,
+ u->urb->transfer_buffer,
+ u->urb->transfer_dma);
+ usb_free_urb(u->urb);
+ u->urb = NULL;
+ }
+}
+
+/*
+ * wait until all urbs are processed.
+ */
+static int wait_clear_urbs(struct snd_usb_substream *subs)
+{
+ unsigned long end_time = jiffies + msecs_to_jiffies(1000);
+ unsigned int i;
+ int alive;
+
+ do {
+ alive = 0;
+ for (i = 0; i < subs->nurbs; i++) {
+ if (test_bit(i, &subs->active_mask))
+ alive++;
+ }
+ if (subs->syncpipe) {
+ for (i = 0; i < SYNC_URBS; i++) {
+ if (test_bit(i + 16, &subs->active_mask))
+ alive++;
+ }
+ }
+ if (! alive)
+ break;
+ schedule_timeout_uninterruptible(1);
+ } while (time_before(jiffies, end_time));
+ if (alive)
+ snd_printk(KERN_ERR "timeout: still %d active urbs..\n", alive);
+ return 0;
+}
+
+/*
+ * release a substream
+ */
+void snd_usb_release_substream_urbs(struct snd_usb_substream *subs, int force)
+{
+ int i;
+
+ /* stop urbs (to be sure) */
+ deactivate_urbs(subs, force, 1);
+ wait_clear_urbs(subs);
+
+ for (i = 0; i < MAX_URBS; i++)
+ release_urb_ctx(&subs->dataurb[i]);
+ for (i = 0; i < SYNC_URBS; i++)
+ release_urb_ctx(&subs->syncurb[i]);
+ usb_free_coherent(subs->dev, SYNC_URBS * 4,
+ subs->syncbuf, subs->sync_dma);
+ subs->syncbuf = NULL;
+ subs->nurbs = 0;
+}
+
+/*
+ * complete callback from data urb
+ */
+static void snd_complete_urb(struct urb *urb)
+{
+ struct snd_urb_ctx *ctx = urb->context;
+ struct snd_usb_substream *subs = ctx->subs;
+ struct snd_pcm_substream *substream = ctx->subs->pcm_substream;
+ int err = 0;
+
+ if ((subs->running && subs->ops.retire(subs, substream->runtime, urb)) ||
+ !subs->running || /* can be stopped during retire callback */
+ (err = subs->ops.prepare(subs, substream->runtime, urb)) < 0 ||
+ (err = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
+ clear_bit(ctx->index, &subs->active_mask);
+ if (err < 0) {
+ snd_printd(KERN_ERR "cannot submit urb (err = %d)\n", err);
+ snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
+ }
+ }
+}
+
+
+/*
+ * complete callback from sync urb
+ */
+static void snd_complete_sync_urb(struct urb *urb)
+{
+ struct snd_urb_ctx *ctx = urb->context;
+ struct snd_usb_substream *subs = ctx->subs;
+ struct snd_pcm_substream *substream = ctx->subs->pcm_substream;
+ int err = 0;
+
+ if ((subs->running && subs->ops.retire_sync(subs, substream->runtime, urb)) ||
+ !subs->running || /* can be stopped during retire callback */
+ (err = subs->ops.prepare_sync(subs, substream->runtime, urb)) < 0 ||
+ (err = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
+ clear_bit(ctx->index + 16, &subs->active_mask);
+ if (err < 0) {
+ snd_printd(KERN_ERR "cannot submit sync urb (err = %d)\n", err);
+ snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
+ }
+ }
+}
+
+
+/*
+ * initialize a substream for plaback/capture
+ */
+int snd_usb_init_substream_urbs(struct snd_usb_substream *subs,
+ unsigned int period_bytes,
+ unsigned int rate,
+ unsigned int frame_bits)
+{
+ unsigned int maxsize, i;
+ int is_playback = subs->direction == SNDRV_PCM_STREAM_PLAYBACK;
+ unsigned int urb_packs, total_packs, packs_per_ms;
+ struct snd_usb_audio *chip = subs->stream->chip;
+
+ /* calculate the frequency in 16.16 format */
+ if (snd_usb_get_speed(subs->dev) == USB_SPEED_FULL)
+ subs->freqn = get_usb_full_speed_rate(rate);
+ else
+ subs->freqn = get_usb_high_speed_rate(rate);
+ subs->freqm = subs->freqn;
+ subs->freqshift = INT_MIN;
+ /* calculate max. frequency */
+ if (subs->maxpacksize) {
+ /* whatever fits into a max. size packet */
+ maxsize = subs->maxpacksize;
+ subs->freqmax = (maxsize / (frame_bits >> 3))
+ << (16 - subs->datainterval);
+ } else {
+ /* no max. packet size: just take 25% higher than nominal */
+ subs->freqmax = subs->freqn + (subs->freqn >> 2);
+ maxsize = ((subs->freqmax + 0xffff) * (frame_bits >> 3))
+ >> (16 - subs->datainterval);
+ }
+ subs->phase = 0;
+
+ if (subs->fill_max)
+ subs->curpacksize = subs->maxpacksize;
+ else
+ subs->curpacksize = maxsize;
+
+ if (snd_usb_get_speed(subs->dev) != USB_SPEED_FULL)
+ packs_per_ms = 8 >> subs->datainterval;
+ else
+ packs_per_ms = 1;
+
+ if (is_playback) {
+ urb_packs = max(chip->nrpacks, 1);
+ urb_packs = min(urb_packs, (unsigned int)MAX_PACKS);
+ } else
+ urb_packs = 1;
+ urb_packs *= packs_per_ms;
+ if (subs->syncpipe)
+ urb_packs = min(urb_packs, 1U << subs->syncinterval);
+
+ /* decide how many packets to be used */
+ if (is_playback) {
+ unsigned int minsize, maxpacks;
+ /* determine how small a packet can be */
+ minsize = (subs->freqn >> (16 - subs->datainterval))
+ * (frame_bits >> 3);
+ /* with sync from device, assume it can be 12% lower */
+ if (subs->syncpipe)
+ minsize -= minsize >> 3;
+ minsize = max(minsize, 1u);
+ total_packs = (period_bytes + minsize - 1) / minsize;
+ /* we need at least two URBs for queueing */
+ if (total_packs < 2) {
+ total_packs = 2;
+ } else {
+ /* and we don't want too long a queue either */
+ maxpacks = max(MAX_QUEUE * packs_per_ms, urb_packs * 2);
+ total_packs = min(total_packs, maxpacks);
+ }
+ } else {
+ while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
+ urb_packs >>= 1;
+ total_packs = MAX_URBS * urb_packs;
+ }
+ subs->nurbs = (total_packs + urb_packs - 1) / urb_packs;
+ if (subs->nurbs > MAX_URBS) {
+ /* too much... */
+ subs->nurbs = MAX_URBS;
+ total_packs = MAX_URBS * urb_packs;
+ } else if (subs->nurbs < 2) {
+ /* too little - we need at least two packets
+ * to ensure contiguous playback/capture
+ */
+ subs->nurbs = 2;
+ }
+
+ /* allocate and initialize data urbs */
+ for (i = 0; i < subs->nurbs; i++) {
+ struct snd_urb_ctx *u = &subs->dataurb[i];
+ u->index = i;
+ u->subs = subs;
+ u->packets = (i + 1) * total_packs / subs->nurbs
+ - i * total_packs / subs->nurbs;
+ u->buffer_size = maxsize * u->packets;
+ if (subs->fmt_type == UAC_FORMAT_TYPE_II)
+ u->packets++; /* for transfer delimiter */
+ u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
+ if (!u->urb)
+ goto out_of_memory;
+ u->urb->transfer_buffer =
+ usb_alloc_coherent(subs->dev, u->buffer_size,
+ GFP_KERNEL, &u->urb->transfer_dma);
+ if (!u->urb->transfer_buffer)
+ goto out_of_memory;
+ u->urb->pipe = subs->datapipe;
+ u->urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
+ u->urb->interval = 1 << subs->datainterval;
+ u->urb->context = u;
+ u->urb->complete = snd_complete_urb;
+ }
+
+ if (subs->syncpipe) {
+ /* allocate and initialize sync urbs */
+ subs->syncbuf = usb_alloc_coherent(subs->dev, SYNC_URBS * 4,
+ GFP_KERNEL, &subs->sync_dma);
+ if (!subs->syncbuf)
+ goto out_of_memory;
+ for (i = 0; i < SYNC_URBS; i++) {
+ struct snd_urb_ctx *u = &subs->syncurb[i];
+ u->index = i;
+ u->subs = subs;
+ u->packets = 1;
+ u->urb = usb_alloc_urb(1, GFP_KERNEL);
+ if (!u->urb)
+ goto out_of_memory;
+ u->urb->transfer_buffer = subs->syncbuf + i * 4;
+ u->urb->transfer_dma = subs->sync_dma + i * 4;
+ u->urb->transfer_buffer_length = 4;
+ u->urb->pipe = subs->syncpipe;
+ u->urb->transfer_flags = URB_ISO_ASAP |
+ URB_NO_TRANSFER_DMA_MAP;
+ u->urb->number_of_packets = 1;
+ u->urb->interval = 1 << subs->syncinterval;
+ u->urb->context = u;
+ u->urb->complete = snd_complete_sync_urb;
+ }
+ }
+ return 0;
+
+out_of_memory:
+ snd_usb_release_substream_urbs(subs, 0);
+ return -ENOMEM;
+}
+
+/*
+ * prepare urb for full speed capture sync pipe
+ *
+ * fill the length and offset of each urb descriptor.
+ * the fixed 10.14 frequency is passed through the pipe.
+ */
+static int prepare_capture_sync_urb(struct snd_usb_substream *subs,
+ struct snd_pcm_runtime *runtime,
+ struct urb *urb)
+{
+ unsigned char *cp = urb->transfer_buffer;
+ struct snd_urb_ctx *ctx = urb->context;
+
+ urb->dev = ctx->subs->dev; /* we need to set this at each time */
+ urb->iso_frame_desc[0].length = 3;
+ urb->iso_frame_desc[0].offset = 0;
+ cp[0] = subs->freqn >> 2;
+ cp[1] = subs->freqn >> 10;
+ cp[2] = subs->freqn >> 18;
+ return 0;
+}
+
+/*
+ * prepare urb for high speed capture sync pipe
+ *
+ * fill the length and offset of each urb descriptor.
+ * the fixed 12.13 frequency is passed as 16.16 through the pipe.
+ */
+static int prepare_capture_sync_urb_hs(struct snd_usb_substream *subs,
+ struct snd_pcm_runtime *runtime,
+ struct urb *urb)
+{
+ unsigned char *cp = urb->transfer_buffer;
+ struct snd_urb_ctx *ctx = urb->context;
+
+ urb->dev = ctx->subs->dev; /* we need to set this at each time */
+ urb->iso_frame_desc[0].length = 4;
+ urb->iso_frame_desc[0].offset = 0;
+ cp[0] = subs->freqn;
+ cp[1] = subs->freqn >> 8;
+ cp[2] = subs->freqn >> 16;
+ cp[3] = subs->freqn >> 24;
+ return 0;
+}
+
+/*
+ * process after capture sync complete
+ * - nothing to do
+ */
+static int retire_capture_sync_urb(struct snd_usb_substream *subs,
+ struct snd_pcm_runtime *runtime,
+ struct urb *urb)
+{
+ return 0;
+}
+
+/*
+ * prepare urb for capture data pipe
+ *
+ * fill the offset and length of each descriptor.
+ *
+ * we use a temporary buffer to write the captured data.
+ * since the length of written data is determined by host, we cannot
+ * write onto the pcm buffer directly... the data is thus copied
+ * later at complete callback to the global buffer.
+ */
+static int prepare_capture_urb(struct snd_usb_substream *subs,
+ struct snd_pcm_runtime *runtime,
+ struct urb *urb)
+{
+ int i, offs;
+ struct snd_urb_ctx *ctx = urb->context;
+
+ offs = 0;
+ urb->dev = ctx->subs->dev; /* we need to set this at each time */
+ for (i = 0; i < ctx->packets; i++) {
+ urb->iso_frame_desc[i].offset = offs;
+ urb->iso_frame_desc[i].length = subs->curpacksize;
+ offs += subs->curpacksize;
+ }
+ urb->transfer_buffer_length = offs;
+ urb->number_of_packets = ctx->packets;
+ return 0;
+}
+
+/*
+ * process after capture complete
+ *
+ * copy the data from each desctiptor to the pcm buffer, and
+ * update the current position.
+ */
+static int retire_capture_urb(struct snd_usb_substream *subs,
+ struct snd_pcm_runtime *runtime,
+ struct urb *urb)
+{
+ unsigned long flags;
+ unsigned char *cp;
+ int i;
+ unsigned int stride, frames, bytes, oldptr;
+ int period_elapsed = 0;
+
+ stride = runtime->frame_bits >> 3;
+
+ for (i = 0; i < urb->number_of_packets; i++) {
+ cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset;
+ if (urb->iso_frame_desc[i].status) {
+ snd_printd(KERN_ERR "frame %d active: %d\n", i, urb->iso_frame_desc[i].status);
+ // continue;
+ }
+ bytes = urb->iso_frame_desc[i].actual_length;
+ frames = bytes / stride;
+ if (!subs->txfr_quirk)
+ bytes = frames * stride;
+ if (bytes % (runtime->sample_bits >> 3) != 0) {
+#ifdef CONFIG_SND_DEBUG_VERBOSE
+ int oldbytes = bytes;
+#endif
+ bytes = frames * stride;
+ snd_printdd(KERN_ERR "Corrected urb data len. %d->%d\n",
+ oldbytes, bytes);
+ }
+ /* update the current pointer */
+ spin_lock_irqsave(&subs->lock, flags);
+ oldptr = subs->hwptr_done;
+ subs->hwptr_done += bytes;
+ if (subs->hwptr_done >= runtime->buffer_size * stride)
+ subs->hwptr_done -= runtime->buffer_size * stride;
+ frames = (bytes + (oldptr % stride)) / stride;
+ subs->transfer_done += frames;
+ if (subs->transfer_done >= runtime->period_size) {
+ subs->transfer_done -= runtime->period_size;
+ period_elapsed = 1;
+ }
+ spin_unlock_irqrestore(&subs->lock, flags);
+ /* copy a data chunk */
+ if (oldptr + bytes > runtime->buffer_size * stride) {
+ unsigned int bytes1 =
+ runtime->buffer_size * stride - oldptr;
+ memcpy(runtime->dma_area + oldptr, cp, bytes1);
+ memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
+ } else {
+ memcpy(runtime->dma_area + oldptr, cp, bytes);
+ }
+ }
+ if (period_elapsed)
+ snd_pcm_period_elapsed(subs->pcm_substream);
+ return 0;
+}
+
+/*
+ * Process after capture complete when paused. Nothing to do.
+ */
+static int retire_paused_capture_urb(struct snd_usb_substream *subs,
+ struct snd_pcm_runtime *runtime,
+ struct urb *urb)
+{
+ return 0;
+}
+
+
+/*
+ * prepare urb for playback sync pipe
+ *
+ * set up the offset and length to receive the current frequency.
+ */
+static int prepare_playback_sync_urb(struct snd_usb_substream *subs,
+ struct snd_pcm_runtime *runtime,
+ struct urb *urb)
+{
+ struct snd_urb_ctx *ctx = urb->context;
+
+ urb->dev = ctx->subs->dev; /* we need to set this at each time */
+ urb->iso_frame_desc[0].length = min(4u, ctx->subs->syncmaxsize);
+ urb->iso_frame_desc[0].offset = 0;
+ return 0;
+}
+
+/*
+ * process after playback sync complete
+ *
+ * Full speed devices report feedback values in 10.14 format as samples per
+ * frame, high speed devices in 16.16 format as samples per microframe.
+ * Because the Audio Class 1 spec was written before USB 2.0, many high speed
+ * devices use a wrong interpretation, some others use an entirely different
+ * format. Therefore, we cannot predict what format any particular device uses
+ * and must detect it automatically.
+ */
+static int retire_playback_sync_urb(struct snd_usb_substream *subs,
+ struct snd_pcm_runtime *runtime,
+ struct urb *urb)
+{
+ unsigned int f;
+ int shift;
+ unsigned long flags;
+
+ if (urb->iso_frame_desc[0].status != 0 ||
+ urb->iso_frame_desc[0].actual_length < 3)
+ return 0;
+
+ f = le32_to_cpup(urb->transfer_buffer);
+ if (urb->iso_frame_desc[0].actual_length == 3)
+ f &= 0x00ffffff;
+ else
+ f &= 0x0fffffff;
+ if (f == 0)
+ return 0;
+
+ if (unlikely(subs->freqshift == INT_MIN)) {
+ /*
+ * The first time we see a feedback value, determine its format
+ * by shifting it left or right until it matches the nominal
+ * frequency value. This assumes that the feedback does not
+ * differ from the nominal value more than +50% or -25%.
+ */
+ shift = 0;
+ while (f < subs->freqn - subs->freqn / 4) {
+ f <<= 1;
+ shift++;
+ }
+ while (f > subs->freqn + subs->freqn / 2) {
+ f >>= 1;
+ shift--;
+ }
+ subs->freqshift = shift;
+ }
+ else if (subs->freqshift >= 0)
+ f <<= subs->freqshift;
+ else
+ f >>= -subs->freqshift;
+
+ if (likely(f >= subs->freqn - subs->freqn / 8 && f <= subs->freqmax)) {
+ /*
+ * If the frequency looks valid, set it.
+ * This value is referred to in prepare_playback_urb().
+ */
+ spin_lock_irqsave(&subs->lock, flags);
+ subs->freqm = f;
+ spin_unlock_irqrestore(&subs->lock, flags);
+ } else {
+ /*
+ * Out of range; maybe the shift value is wrong.
+ * Reset it so that we autodetect again the next time.
+ */
+ subs->freqshift = INT_MIN;
+ }
+
+ return 0;
+}
+
+/* determine the number of frames in the next packet */
+static int snd_usb_audio_next_packet_size(struct snd_usb_substream *subs)
+{
+ if (subs->fill_max)
+ return subs->maxframesize;
+ else {
+ subs->phase = (subs->phase & 0xffff)
+ + (subs->freqm << subs->datainterval);
+ return min(subs->phase >> 16, subs->maxframesize);
+ }
+}
+
+/*
+ * Prepare urb for streaming before playback starts or when paused.
+ *
+ * We don't have any data, so we send silence.
+ */
+static int prepare_nodata_playback_urb(struct snd_usb_substream *subs,
+ struct snd_pcm_runtime *runtime,
+ struct urb *urb)
+{
+ unsigned int i, offs, counts;
+ struct snd_urb_ctx *ctx = urb->context;
+ int stride = runtime->frame_bits >> 3;
+
+ offs = 0;
+ urb->dev = ctx->subs->dev;
+ for (i = 0; i < ctx->packets; ++i) {
+ counts = snd_usb_audio_next_packet_size(subs);
+ urb->iso_frame_desc[i].offset = offs * stride;
+ urb->iso_frame_desc[i].length = counts * stride;
+ offs += counts;
+ }
+ urb->number_of_packets = ctx->packets;
+ urb->transfer_buffer_length = offs * stride;
+ memset(urb->transfer_buffer,
+ runtime->format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0,
+ offs * stride);
+ return 0;
+}
+
+/*
+ * prepare urb for playback data pipe
+ *
+ * Since a URB can handle only a single linear buffer, we must use double
+ * buffering when the data to be transferred overflows the buffer boundary.
+ * To avoid inconsistencies when updating hwptr_done, we use double buffering
+ * for all URBs.
+ */
+static int prepare_playback_urb(struct snd_usb_substream *subs,
+ struct snd_pcm_runtime *runtime,
+ struct urb *urb)
+{
+ int i, stride;
+ unsigned int counts, frames, bytes;
+ unsigned long flags;
+ int period_elapsed = 0;
+ struct snd_urb_ctx *ctx = urb->context;
+
+ stride = runtime->frame_bits >> 3;
+
+ frames = 0;
+ urb->dev = ctx->subs->dev; /* we need to set this at each time */
+ urb->number_of_packets = 0;
+ spin_lock_irqsave(&subs->lock, flags);
+ for (i = 0; i < ctx->packets; i++) {
+ counts = snd_usb_audio_next_packet_size(subs);
+ /* set up descriptor */
+ urb->iso_frame_desc[i].offset = frames * stride;
+ urb->iso_frame_desc[i].length = counts * stride;
+ frames += counts;
+ urb->number_of_packets++;
+ subs->transfer_done += counts;
+ if (subs->transfer_done >= runtime->period_size) {
+ subs->transfer_done -= runtime->period_size;
+ period_elapsed = 1;
+ if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
+ if (subs->transfer_done > 0) {
+ /* FIXME: fill-max mode is not
+ * supported yet */
+ frames -= subs->transfer_done;
+ counts -= subs->transfer_done;
+ urb->iso_frame_desc[i].length =
+ counts * stride;
+ subs->transfer_done = 0;
+ }
+ i++;
+ if (i < ctx->packets) {
+ /* add a transfer delimiter */
+ urb->iso_frame_desc[i].offset =
+ frames * stride;
+ urb->iso_frame_desc[i].length = 0;
+ urb->number_of_packets++;
+ }
+ break;
+ }
+ }
+ if (period_elapsed) /* finish at the period boundary */
+ break;
+ }
+ bytes = frames * stride;
+ if (subs->hwptr_done + bytes > runtime->buffer_size * stride) {
+ /* err, the transferred area goes over buffer boundary. */
+ unsigned int bytes1 =
+ runtime->buffer_size * stride - subs->hwptr_done;
+ memcpy(urb->transfer_buffer,
+ runtime->dma_area + subs->hwptr_done, bytes1);
+ memcpy(urb->transfer_buffer + bytes1,
+ runtime->dma_area, bytes - bytes1);
+ } else {
+ memcpy(urb->transfer_buffer,
+ runtime->dma_area + subs->hwptr_done, bytes);
+ }
+ subs->hwptr_done += bytes;
+ if (subs->hwptr_done >= runtime->buffer_size * stride)
+ subs->hwptr_done -= runtime->buffer_size * stride;
+
+ /* update delay with exact number of samples queued */
+ runtime->delay = subs->last_delay;
+ runtime->delay += frames;
+ subs->last_delay = runtime->delay;
+
+ /* realign last_frame_number */
+ subs->last_frame_number = usb_get_current_frame_number(subs->dev);
+ subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
+
+ spin_unlock_irqrestore(&subs->lock, flags);
+ urb->transfer_buffer_length = bytes;
+ if (period_elapsed)
+ snd_pcm_period_elapsed(subs->pcm_substream);
+ return 0;
+}
+
+/*
+ * process after playback data complete
+ * - decrease the delay count again
+ */
+static int retire_playback_urb(struct snd_usb_substream *subs,
+ struct snd_pcm_runtime *runtime,
+ struct urb *urb)
+{
+ unsigned long flags;
+ int stride = runtime->frame_bits >> 3;
+ int processed = urb->transfer_buffer_length / stride;
+ int est_delay;
+
+ spin_lock_irqsave(&subs->lock, flags);
+
+ est_delay = snd_usb_pcm_delay(subs, runtime->rate);
+ /* update delay with exact number of samples played */
+ if (processed > subs->last_delay)
+ subs->last_delay = 0;
+ else
+ subs->last_delay -= processed;
+ runtime->delay = subs->last_delay;
+
+ /*
+ * Report when delay estimate is off by more than 2ms.
+ * The error should be lower than 2ms since the estimate relies
+ * on two reads of a counter updated every ms.
+ */
+ if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
+ snd_printk(KERN_DEBUG "delay: estimated %d, actual %d\n",
+ est_delay, subs->last_delay);
+
+ spin_unlock_irqrestore(&subs->lock, flags);
+ return 0;
+}
+
+static const char *usb_error_string(int err)
+{
+ switch (err) {
+ case -ENODEV:
+ return "no device";
+ case -ENOENT:
+ return "endpoint not enabled";
+ case -EPIPE:
+ return "endpoint stalled";
+ case -ENOSPC:
+ return "not enough bandwidth";
+ case -ESHUTDOWN:
+ return "device disabled";
+ case -EHOSTUNREACH:
+ return "device suspended";
+ case -EINVAL:
+ case -EAGAIN:
+ case -EFBIG:
+ case -EMSGSIZE:
+ return "internal error";
+ default:
+ return "unknown error";
+ }
+}
+
+/*
+ * set up and start data/sync urbs
+ */
+static int start_urbs(struct snd_usb_substream *subs, struct snd_pcm_runtime *runtime)
+{
+ unsigned int i;
+ int err;
+
+ if (subs->stream->chip->shutdown)
+ return -EBADFD;
+
+ for (i = 0; i < subs->nurbs; i++) {
+ if (snd_BUG_ON(!subs->dataurb[i].urb))
+ return -EINVAL;
+ if (subs->ops.prepare(subs, runtime, subs->dataurb[i].urb) < 0) {
+ snd_printk(KERN_ERR "cannot prepare datapipe for urb %d\n", i);
+ goto __error;
+ }
+ }
+ if (subs->syncpipe) {
+ for (i = 0; i < SYNC_URBS; i++) {
+ if (snd_BUG_ON(!subs->syncurb[i].urb))
+ return -EINVAL;
+ if (subs->ops.prepare_sync(subs, runtime, subs->syncurb[i].urb) < 0) {
+ snd_printk(KERN_ERR "cannot prepare syncpipe for urb %d\n", i);
+ goto __error;
+ }
+ }
+ }
+
+ subs->active_mask = 0;
+ subs->unlink_mask = 0;
+ subs->running = 1;
+ for (i = 0; i < subs->nurbs; i++) {
+ err = usb_submit_urb(subs->dataurb[i].urb, GFP_ATOMIC);
+ if (err < 0) {
+ snd_printk(KERN_ERR "cannot submit datapipe "
+ "for urb %d, error %d: %s\n",
+ i, err, usb_error_string(err));
+ goto __error;
+ }
+ set_bit(i, &subs->active_mask);
+ }
+ if (subs->syncpipe) {
+ for (i = 0; i < SYNC_URBS; i++) {
+ err = usb_submit_urb(subs->syncurb[i].urb, GFP_ATOMIC);
+ if (err < 0) {
+ snd_printk(KERN_ERR "cannot submit syncpipe "
+ "for urb %d, error %d: %s\n",
+ i, err, usb_error_string(err));
+ goto __error;
+ }
+ set_bit(i + 16, &subs->active_mask);
+ }
+ }
+ return 0;
+
+ __error:
+ // snd_pcm_stop(subs->pcm_substream, SNDRV_PCM_STATE_XRUN);
+ deactivate_urbs(subs, 0, 0);
+ return -EPIPE;
+}
+
+
+/*
+ */
+static struct snd_urb_ops audio_urb_ops[2] = {
+ {
+ .prepare = prepare_nodata_playback_urb,
+ .retire = retire_playback_urb,
+ .prepare_sync = prepare_playback_sync_urb,
+ .retire_sync = retire_playback_sync_urb,
+ },
+ {
+ .prepare = prepare_capture_urb,
+ .retire = retire_capture_urb,
+ .prepare_sync = prepare_capture_sync_urb,
+ .retire_sync = retire_capture_sync_urb,
+ },
+};
+
+/*
+ * initialize the substream instance.
+ */
+
+void snd_usb_init_substream(struct snd_usb_stream *as,
+ int stream, struct audioformat *fp)
+{
+ struct snd_usb_substream *subs = &as->substream[stream];
+
+ INIT_LIST_HEAD(&subs->fmt_list);
+ spin_lock_init(&subs->lock);
+
+ subs->stream = as;
+ subs->direction = stream;
+ subs->dev = as->chip->dev;
+ subs->txfr_quirk = as->chip->txfr_quirk;
+ subs->ops = audio_urb_ops[stream];
+ if (snd_usb_get_speed(subs->dev) >= USB_SPEED_HIGH)
+ subs->ops.prepare_sync = prepare_capture_sync_urb_hs;
+
+ snd_usb_set_pcm_ops(as->pcm, stream);
+
+ list_add_tail(&fp->list, &subs->fmt_list);
+ subs->formats |= fp->formats;
+ subs->endpoint = fp->endpoint;
+ subs->num_formats++;
+ subs->fmt_type = fp->fmt_type;
+}
+
+int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+ struct snd_usb_substream *subs = substream->runtime->private_data;
+
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+ subs->ops.prepare = prepare_playback_urb;
+ return 0;
+ case SNDRV_PCM_TRIGGER_STOP:
+ return deactivate_urbs(subs, 0, 0);
+ case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+ subs->ops.prepare = prepare_nodata_playback_urb;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+ struct snd_usb_substream *subs = substream->runtime->private_data;
+
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ subs->ops.retire = retire_capture_urb;
+ return start_urbs(subs, substream->runtime);
+ case SNDRV_PCM_TRIGGER_STOP:
+ return deactivate_urbs(subs, 0, 0);
+ case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+ subs->ops.retire = retire_paused_capture_urb;
+ return 0;
+ case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+ subs->ops.retire = retire_capture_urb;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+int snd_usb_substream_prepare(struct snd_usb_substream *subs,
+ struct snd_pcm_runtime *runtime)
+{
+ /* clear urbs (to be sure) */
+ deactivate_urbs(subs, 0, 1);
+ wait_clear_urbs(subs);
+
+ /* for playback, submit the URBs now; otherwise, the first hwptr_done
+ * updates for all URBs would happen at the same time when starting */
+ if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK) {
+ subs->ops.prepare = prepare_nodata_playback_urb;
+ return start_urbs(subs, runtime);
+ }
+
+ return 0;
+}
+