v4.19.13 snapshot.
diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
new file mode 100644
index 0000000..d86be8b
--- /dev/null
+++ b/sound/usb/endpoint.c
@@ -0,0 +1,1230 @@
+/*
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <linux/gfp.h>
+#include <linux/init.h>
+#include <linux/ratelimit.h>
+#include <linux/usb.h>
+#include <linux/usb/audio.h>
+#include <linux/slab.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+
+#include "usbaudio.h"
+#include "helper.h"
+#include "card.h"
+#include "endpoint.h"
+#include "pcm.h"
+#include "quirks.h"
+
+#define EP_FLAG_RUNNING 1
+#define EP_FLAG_STOPPING 2
+
+/*
+ * snd_usb_endpoint is a model that abstracts everything related to an
+ * USB endpoint and its streaming.
+ *
+ * There are functions to activate and deactivate the streaming URBs and
+ * optional callbacks to let the pcm logic handle the actual content of the
+ * packets for playback and record. Thus, the bus streaming and the audio
+ * handlers are fully decoupled.
+ *
+ * There are two different types of endpoints in audio applications.
+ *
+ * SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
+ * inbound and outbound traffic.
+ *
+ * SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
+ * expect the payload to carry Q10.14 / Q16.16 formatted sync information
+ * (3 or 4 bytes).
+ *
+ * Each endpoint has to be configured prior to being used by calling
+ * snd_usb_endpoint_set_params().
+ *
+ * The model incorporates a reference counting, so that multiple users
+ * can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
+ * only the first user will effectively start the URBs, and only the last
+ * one to stop it will tear the URBs down again.
+ */
+
+/*
+ * 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;
+}
+
+/*
+ * release a urb data
+ */
+static void release_urb_ctx(struct snd_urb_ctx *u)
+{
+ if (u->buffer_size)
+ usb_free_coherent(u->ep->chip->dev, u->buffer_size,
+ u->urb->transfer_buffer,
+ u->urb->transfer_dma);
+ usb_free_urb(u->urb);
+ u->urb = NULL;
+}
+
+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";
+ }
+}
+
+/**
+ * snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
+ *
+ * @ep: The snd_usb_endpoint
+ *
+ * Determine whether an endpoint is driven by an implicit feedback
+ * data endpoint source.
+ */
+int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep)
+{
+ return ep->sync_master &&
+ ep->sync_master->type == SND_USB_ENDPOINT_TYPE_DATA &&
+ ep->type == SND_USB_ENDPOINT_TYPE_DATA &&
+ usb_pipeout(ep->pipe);
+}
+
+/*
+ * For streaming based on information derived from sync endpoints,
+ * prepare_outbound_urb_sizes() will call next_packet_size() to
+ * determine the number of samples to be sent in the next packet.
+ *
+ * For implicit feedback, next_packet_size() is unused.
+ */
+int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep)
+{
+ unsigned long flags;
+ int ret;
+
+ if (ep->fill_max)
+ return ep->maxframesize;
+
+ spin_lock_irqsave(&ep->lock, flags);
+ ep->phase = (ep->phase & 0xffff)
+ + (ep->freqm << ep->datainterval);
+ ret = min(ep->phase >> 16, ep->maxframesize);
+ spin_unlock_irqrestore(&ep->lock, flags);
+
+ return ret;
+}
+
+static void retire_outbound_urb(struct snd_usb_endpoint *ep,
+ struct snd_urb_ctx *urb_ctx)
+{
+ if (ep->retire_data_urb)
+ ep->retire_data_urb(ep->data_subs, urb_ctx->urb);
+}
+
+static void retire_inbound_urb(struct snd_usb_endpoint *ep,
+ struct snd_urb_ctx *urb_ctx)
+{
+ struct urb *urb = urb_ctx->urb;
+
+ if (unlikely(ep->skip_packets > 0)) {
+ ep->skip_packets--;
+ return;
+ }
+
+ if (ep->sync_slave)
+ snd_usb_handle_sync_urb(ep->sync_slave, ep, urb);
+
+ if (ep->retire_data_urb)
+ ep->retire_data_urb(ep->data_subs, urb);
+}
+
+static void prepare_silent_urb(struct snd_usb_endpoint *ep,
+ struct snd_urb_ctx *ctx)
+{
+ struct urb *urb = ctx->urb;
+ unsigned int offs = 0;
+ unsigned int extra = 0;
+ __le32 packet_length;
+ int i;
+
+ /* For tx_length_quirk, put packet length at start of packet */
+ if (ep->chip->tx_length_quirk)
+ extra = sizeof(packet_length);
+
+ for (i = 0; i < ctx->packets; ++i) {
+ unsigned int offset;
+ unsigned int length;
+ int counts;
+
+ if (ctx->packet_size[i])
+ counts = ctx->packet_size[i];
+ else
+ counts = snd_usb_endpoint_next_packet_size(ep);
+
+ length = counts * ep->stride; /* number of silent bytes */
+ offset = offs * ep->stride + extra * i;
+ urb->iso_frame_desc[i].offset = offset;
+ urb->iso_frame_desc[i].length = length + extra;
+ if (extra) {
+ packet_length = cpu_to_le32(length);
+ memcpy(urb->transfer_buffer + offset,
+ &packet_length, sizeof(packet_length));
+ }
+ memset(urb->transfer_buffer + offset + extra,
+ ep->silence_value, length);
+ offs += counts;
+ }
+
+ urb->number_of_packets = ctx->packets;
+ urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra;
+}
+
+/*
+ * Prepare a PLAYBACK urb for submission to the bus.
+ */
+static void prepare_outbound_urb(struct snd_usb_endpoint *ep,
+ struct snd_urb_ctx *ctx)
+{
+ struct urb *urb = ctx->urb;
+ unsigned char *cp = urb->transfer_buffer;
+
+ urb->dev = ep->chip->dev; /* we need to set this at each time */
+
+ switch (ep->type) {
+ case SND_USB_ENDPOINT_TYPE_DATA:
+ if (ep->prepare_data_urb) {
+ ep->prepare_data_urb(ep->data_subs, urb);
+ } else {
+ /* no data provider, so send silence */
+ prepare_silent_urb(ep, ctx);
+ }
+ break;
+
+ case SND_USB_ENDPOINT_TYPE_SYNC:
+ if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
+ /*
+ * fill the length and offset of each urb descriptor.
+ * the fixed 12.13 frequency is passed as 16.16 through the pipe.
+ */
+ urb->iso_frame_desc[0].length = 4;
+ urb->iso_frame_desc[0].offset = 0;
+ cp[0] = ep->freqn;
+ cp[1] = ep->freqn >> 8;
+ cp[2] = ep->freqn >> 16;
+ cp[3] = ep->freqn >> 24;
+ } else {
+ /*
+ * fill the length and offset of each urb descriptor.
+ * the fixed 10.14 frequency is passed through the pipe.
+ */
+ urb->iso_frame_desc[0].length = 3;
+ urb->iso_frame_desc[0].offset = 0;
+ cp[0] = ep->freqn >> 2;
+ cp[1] = ep->freqn >> 10;
+ cp[2] = ep->freqn >> 18;
+ }
+
+ break;
+ }
+}
+
+/*
+ * Prepare a CAPTURE or SYNC urb for submission to the bus.
+ */
+static inline void prepare_inbound_urb(struct snd_usb_endpoint *ep,
+ struct snd_urb_ctx *urb_ctx)
+{
+ int i, offs;
+ struct urb *urb = urb_ctx->urb;
+
+ urb->dev = ep->chip->dev; /* we need to set this at each time */
+
+ switch (ep->type) {
+ case SND_USB_ENDPOINT_TYPE_DATA:
+ offs = 0;
+ for (i = 0; i < urb_ctx->packets; i++) {
+ urb->iso_frame_desc[i].offset = offs;
+ urb->iso_frame_desc[i].length = ep->curpacksize;
+ offs += ep->curpacksize;
+ }
+
+ urb->transfer_buffer_length = offs;
+ urb->number_of_packets = urb_ctx->packets;
+ break;
+
+ case SND_USB_ENDPOINT_TYPE_SYNC:
+ urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
+ urb->iso_frame_desc[0].offset = 0;
+ break;
+ }
+}
+
+/*
+ * Send output urbs that have been prepared previously. URBs are dequeued
+ * from ep->ready_playback_urbs and in case there there aren't any available
+ * or there are no packets that have been prepared, this function does
+ * nothing.
+ *
+ * The reason why the functionality of sending and preparing URBs is separated
+ * is that host controllers don't guarantee the order in which they return
+ * inbound and outbound packets to their submitters.
+ *
+ * This function is only used for implicit feedback endpoints. For endpoints
+ * driven by dedicated sync endpoints, URBs are immediately re-submitted
+ * from their completion handler.
+ */
+static void queue_pending_output_urbs(struct snd_usb_endpoint *ep)
+{
+ while (test_bit(EP_FLAG_RUNNING, &ep->flags)) {
+
+ unsigned long flags;
+ struct snd_usb_packet_info *uninitialized_var(packet);
+ struct snd_urb_ctx *ctx = NULL;
+ int err, i;
+
+ spin_lock_irqsave(&ep->lock, flags);
+ if (ep->next_packet_read_pos != ep->next_packet_write_pos) {
+ packet = ep->next_packet + ep->next_packet_read_pos;
+ ep->next_packet_read_pos++;
+ ep->next_packet_read_pos %= MAX_URBS;
+
+ /* take URB out of FIFO */
+ if (!list_empty(&ep->ready_playback_urbs))
+ ctx = list_first_entry(&ep->ready_playback_urbs,
+ struct snd_urb_ctx, ready_list);
+ }
+ spin_unlock_irqrestore(&ep->lock, flags);
+
+ if (ctx == NULL)
+ return;
+
+ list_del_init(&ctx->ready_list);
+
+ /* copy over the length information */
+ for (i = 0; i < packet->packets; i++)
+ ctx->packet_size[i] = packet->packet_size[i];
+
+ /* call the data handler to fill in playback data */
+ prepare_outbound_urb(ep, ctx);
+
+ err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
+ if (err < 0)
+ usb_audio_err(ep->chip,
+ "Unable to submit urb #%d: %d (urb %p)\n",
+ ctx->index, err, ctx->urb);
+ else
+ set_bit(ctx->index, &ep->active_mask);
+ }
+}
+
+/*
+ * complete callback for urbs
+ */
+static void snd_complete_urb(struct urb *urb)
+{
+ struct snd_urb_ctx *ctx = urb->context;
+ struct snd_usb_endpoint *ep = ctx->ep;
+ struct snd_pcm_substream *substream;
+ unsigned long flags;
+ int err;
+
+ if (unlikely(urb->status == -ENOENT || /* unlinked */
+ urb->status == -ENODEV || /* device removed */
+ urb->status == -ECONNRESET || /* unlinked */
+ urb->status == -ESHUTDOWN)) /* device disabled */
+ goto exit_clear;
+ /* device disconnected */
+ if (unlikely(atomic_read(&ep->chip->shutdown)))
+ goto exit_clear;
+
+ if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
+ goto exit_clear;
+
+ if (usb_pipeout(ep->pipe)) {
+ retire_outbound_urb(ep, ctx);
+ /* can be stopped during retire callback */
+ if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
+ goto exit_clear;
+
+ if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
+ spin_lock_irqsave(&ep->lock, flags);
+ list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
+ spin_unlock_irqrestore(&ep->lock, flags);
+ queue_pending_output_urbs(ep);
+
+ goto exit_clear;
+ }
+
+ prepare_outbound_urb(ep, ctx);
+ } else {
+ retire_inbound_urb(ep, ctx);
+ /* can be stopped during retire callback */
+ if (unlikely(!test_bit(EP_FLAG_RUNNING, &ep->flags)))
+ goto exit_clear;
+
+ prepare_inbound_urb(ep, ctx);
+ }
+
+ err = usb_submit_urb(urb, GFP_ATOMIC);
+ if (err == 0)
+ return;
+
+ usb_audio_err(ep->chip, "cannot submit urb (err = %d)\n", err);
+ if (ep->data_subs && ep->data_subs->pcm_substream) {
+ substream = ep->data_subs->pcm_substream;
+ snd_pcm_stop_xrun(substream);
+ }
+
+exit_clear:
+ clear_bit(ctx->index, &ep->active_mask);
+}
+
+/**
+ * snd_usb_add_endpoint: Add an endpoint to an USB audio chip
+ *
+ * @chip: The chip
+ * @alts: The USB host interface
+ * @ep_num: The number of the endpoint to use
+ * @direction: SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE
+ * @type: SND_USB_ENDPOINT_TYPE_DATA or SND_USB_ENDPOINT_TYPE_SYNC
+ *
+ * If the requested endpoint has not been added to the given chip before,
+ * a new instance is created. Otherwise, a pointer to the previoulsy
+ * created instance is returned. In case of any error, NULL is returned.
+ *
+ * New endpoints will be added to chip->ep_list and must be freed by
+ * calling snd_usb_endpoint_free().
+ *
+ * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
+ * bNumEndpoints > 1 beforehand.
+ */
+struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
+ struct usb_host_interface *alts,
+ int ep_num, int direction, int type)
+{
+ struct snd_usb_endpoint *ep;
+ int is_playback = direction == SNDRV_PCM_STREAM_PLAYBACK;
+
+ if (WARN_ON(!alts))
+ return NULL;
+
+ mutex_lock(&chip->mutex);
+
+ list_for_each_entry(ep, &chip->ep_list, list) {
+ if (ep->ep_num == ep_num &&
+ ep->iface == alts->desc.bInterfaceNumber &&
+ ep->altsetting == alts->desc.bAlternateSetting) {
+ usb_audio_dbg(ep->chip,
+ "Re-using EP %x in iface %d,%d @%p\n",
+ ep_num, ep->iface, ep->altsetting, ep);
+ goto __exit_unlock;
+ }
+ }
+
+ usb_audio_dbg(chip, "Creating new %s %s endpoint #%x\n",
+ is_playback ? "playback" : "capture",
+ type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync",
+ ep_num);
+
+ ep = kzalloc(sizeof(*ep), GFP_KERNEL);
+ if (!ep)
+ goto __exit_unlock;
+
+ ep->chip = chip;
+ spin_lock_init(&ep->lock);
+ ep->type = type;
+ ep->ep_num = ep_num;
+ ep->iface = alts->desc.bInterfaceNumber;
+ ep->altsetting = alts->desc.bAlternateSetting;
+ INIT_LIST_HEAD(&ep->ready_playback_urbs);
+ ep_num &= USB_ENDPOINT_NUMBER_MASK;
+
+ if (is_playback)
+ ep->pipe = usb_sndisocpipe(chip->dev, ep_num);
+ else
+ ep->pipe = usb_rcvisocpipe(chip->dev, ep_num);
+
+ if (type == SND_USB_ENDPOINT_TYPE_SYNC) {
+ if (get_endpoint(alts, 1)->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
+ get_endpoint(alts, 1)->bRefresh >= 1 &&
+ get_endpoint(alts, 1)->bRefresh <= 9)
+ ep->syncinterval = get_endpoint(alts, 1)->bRefresh;
+ else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
+ ep->syncinterval = 1;
+ else if (get_endpoint(alts, 1)->bInterval >= 1 &&
+ get_endpoint(alts, 1)->bInterval <= 16)
+ ep->syncinterval = get_endpoint(alts, 1)->bInterval - 1;
+ else
+ ep->syncinterval = 3;
+
+ ep->syncmaxsize = le16_to_cpu(get_endpoint(alts, 1)->wMaxPacketSize);
+ }
+
+ list_add_tail(&ep->list, &chip->ep_list);
+
+__exit_unlock:
+ mutex_unlock(&chip->mutex);
+
+ return ep;
+}
+
+/*
+ * wait until all urbs are processed.
+ */
+static int wait_clear_urbs(struct snd_usb_endpoint *ep)
+{
+ unsigned long end_time = jiffies + msecs_to_jiffies(1000);
+ int alive;
+
+ do {
+ alive = bitmap_weight(&ep->active_mask, ep->nurbs);
+ if (!alive)
+ break;
+
+ schedule_timeout_uninterruptible(1);
+ } while (time_before(jiffies, end_time));
+
+ if (alive)
+ usb_audio_err(ep->chip,
+ "timeout: still %d active urbs on EP #%x\n",
+ alive, ep->ep_num);
+ clear_bit(EP_FLAG_STOPPING, &ep->flags);
+
+ ep->data_subs = NULL;
+ ep->sync_slave = NULL;
+ ep->retire_data_urb = NULL;
+ ep->prepare_data_urb = NULL;
+
+ return 0;
+}
+
+/* sync the pending stop operation;
+ * this function itself doesn't trigger the stop operation
+ */
+void snd_usb_endpoint_sync_pending_stop(struct snd_usb_endpoint *ep)
+{
+ if (ep && test_bit(EP_FLAG_STOPPING, &ep->flags))
+ wait_clear_urbs(ep);
+}
+
+/*
+ * unlink active urbs.
+ */
+static int deactivate_urbs(struct snd_usb_endpoint *ep, bool force)
+{
+ unsigned int i;
+
+ if (!force && atomic_read(&ep->chip->shutdown)) /* to be sure... */
+ return -EBADFD;
+
+ clear_bit(EP_FLAG_RUNNING, &ep->flags);
+
+ INIT_LIST_HEAD(&ep->ready_playback_urbs);
+ ep->next_packet_read_pos = 0;
+ ep->next_packet_write_pos = 0;
+
+ for (i = 0; i < ep->nurbs; i++) {
+ if (test_bit(i, &ep->active_mask)) {
+ if (!test_and_set_bit(i, &ep->unlink_mask)) {
+ struct urb *u = ep->urb[i].urb;
+ usb_unlink_urb(u);
+ }
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * release an endpoint's urbs
+ */
+static void release_urbs(struct snd_usb_endpoint *ep, int force)
+{
+ int i;
+
+ /* route incoming urbs to nirvana */
+ ep->retire_data_urb = NULL;
+ ep->prepare_data_urb = NULL;
+
+ /* stop urbs */
+ deactivate_urbs(ep, force);
+ wait_clear_urbs(ep);
+
+ for (i = 0; i < ep->nurbs; i++)
+ release_urb_ctx(&ep->urb[i]);
+
+ if (ep->syncbuf)
+ usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
+ ep->syncbuf, ep->sync_dma);
+
+ ep->syncbuf = NULL;
+ ep->nurbs = 0;
+}
+
+/*
+ * configure a data endpoint
+ */
+static int data_ep_set_params(struct snd_usb_endpoint *ep,
+ snd_pcm_format_t pcm_format,
+ unsigned int channels,
+ unsigned int period_bytes,
+ unsigned int frames_per_period,
+ unsigned int periods_per_buffer,
+ struct audioformat *fmt,
+ struct snd_usb_endpoint *sync_ep)
+{
+ unsigned int maxsize, minsize, packs_per_ms, max_packs_per_urb;
+ unsigned int max_packs_per_period, urbs_per_period, urb_packs;
+ unsigned int max_urbs, i;
+ int frame_bits = snd_pcm_format_physical_width(pcm_format) * channels;
+ int tx_length_quirk = (ep->chip->tx_length_quirk &&
+ usb_pipeout(ep->pipe));
+
+ if (pcm_format == SNDRV_PCM_FORMAT_DSD_U16_LE && fmt->dsd_dop) {
+ /*
+ * When operating in DSD DOP mode, the size of a sample frame
+ * in hardware differs from the actual physical format width
+ * because we need to make room for the DOP markers.
+ */
+ frame_bits += channels << 3;
+ }
+
+ ep->datainterval = fmt->datainterval;
+ ep->stride = frame_bits >> 3;
+
+ switch (pcm_format) {
+ case SNDRV_PCM_FORMAT_U8:
+ ep->silence_value = 0x80;
+ break;
+ case SNDRV_PCM_FORMAT_DSD_U8:
+ case SNDRV_PCM_FORMAT_DSD_U16_LE:
+ case SNDRV_PCM_FORMAT_DSD_U32_LE:
+ case SNDRV_PCM_FORMAT_DSD_U16_BE:
+ case SNDRV_PCM_FORMAT_DSD_U32_BE:
+ ep->silence_value = 0x69;
+ break;
+ default:
+ ep->silence_value = 0;
+ }
+
+ /* assume max. frequency is 50% higher than nominal */
+ ep->freqmax = ep->freqn + (ep->freqn >> 1);
+ /* Round up freqmax to nearest integer in order to calculate maximum
+ * packet size, which must represent a whole number of frames.
+ * This is accomplished by adding 0x0.ffff before converting the
+ * Q16.16 format into integer.
+ * In order to accurately calculate the maximum packet size when
+ * the data interval is more than 1 (i.e. ep->datainterval > 0),
+ * multiply by the data interval prior to rounding. For instance,
+ * a freqmax of 41 kHz will result in a max packet size of 6 (5.125)
+ * frames with a data interval of 1, but 11 (10.25) frames with a
+ * data interval of 2.
+ * (ep->freqmax << ep->datainterval overflows at 8.192 MHz for the
+ * maximum datainterval value of 3, at USB full speed, higher for
+ * USB high speed, noting that ep->freqmax is in units of
+ * frames per packet in Q16.16 format.)
+ */
+ maxsize = (((ep->freqmax << ep->datainterval) + 0xffff) >> 16) *
+ (frame_bits >> 3);
+ if (tx_length_quirk)
+ maxsize += sizeof(__le32); /* Space for length descriptor */
+ /* but wMaxPacketSize might reduce this */
+ if (ep->maxpacksize && ep->maxpacksize < maxsize) {
+ /* whatever fits into a max. size packet */
+ unsigned int data_maxsize = maxsize = ep->maxpacksize;
+
+ if (tx_length_quirk)
+ /* Need to remove the length descriptor to calc freq */
+ data_maxsize -= sizeof(__le32);
+ ep->freqmax = (data_maxsize / (frame_bits >> 3))
+ << (16 - ep->datainterval);
+ }
+
+ if (ep->fill_max)
+ ep->curpacksize = ep->maxpacksize;
+ else
+ ep->curpacksize = maxsize;
+
+ if (snd_usb_get_speed(ep->chip->dev) != USB_SPEED_FULL) {
+ packs_per_ms = 8 >> ep->datainterval;
+ max_packs_per_urb = MAX_PACKS_HS;
+ } else {
+ packs_per_ms = 1;
+ max_packs_per_urb = MAX_PACKS;
+ }
+ if (sync_ep && !snd_usb_endpoint_implicit_feedback_sink(ep))
+ max_packs_per_urb = min(max_packs_per_urb,
+ 1U << sync_ep->syncinterval);
+ max_packs_per_urb = max(1u, max_packs_per_urb >> ep->datainterval);
+
+ /*
+ * Capture endpoints need to use small URBs because there's no way
+ * to tell in advance where the next period will end, and we don't
+ * want the next URB to complete much after the period ends.
+ *
+ * Playback endpoints with implicit sync much use the same parameters
+ * as their corresponding capture endpoint.
+ */
+ if (usb_pipein(ep->pipe) ||
+ snd_usb_endpoint_implicit_feedback_sink(ep)) {
+
+ urb_packs = packs_per_ms;
+ /*
+ * Wireless devices can poll at a max rate of once per 4ms.
+ * For dataintervals less than 5, increase the packet count to
+ * allow the host controller to use bursting to fill in the
+ * gaps.
+ */
+ if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_WIRELESS) {
+ int interval = ep->datainterval;
+ while (interval < 5) {
+ urb_packs <<= 1;
+ ++interval;
+ }
+ }
+ /* make capture URBs <= 1 ms and smaller than a period */
+ urb_packs = min(max_packs_per_urb, urb_packs);
+ while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
+ urb_packs >>= 1;
+ ep->nurbs = MAX_URBS;
+
+ /*
+ * Playback endpoints without implicit sync are adjusted so that
+ * a period fits as evenly as possible in the smallest number of
+ * URBs. The total number of URBs is adjusted to the size of the
+ * ALSA buffer, subject to the MAX_URBS and MAX_QUEUE limits.
+ */
+ } else {
+ /* determine how small a packet can be */
+ minsize = (ep->freqn >> (16 - ep->datainterval)) *
+ (frame_bits >> 3);
+ /* with sync from device, assume it can be 12% lower */
+ if (sync_ep)
+ minsize -= minsize >> 3;
+ minsize = max(minsize, 1u);
+
+ /* how many packets will contain an entire ALSA period? */
+ max_packs_per_period = DIV_ROUND_UP(period_bytes, minsize);
+
+ /* how many URBs will contain a period? */
+ urbs_per_period = DIV_ROUND_UP(max_packs_per_period,
+ max_packs_per_urb);
+ /* how many packets are needed in each URB? */
+ urb_packs = DIV_ROUND_UP(max_packs_per_period, urbs_per_period);
+
+ /* limit the number of frames in a single URB */
+ ep->max_urb_frames = DIV_ROUND_UP(frames_per_period,
+ urbs_per_period);
+
+ /* try to use enough URBs to contain an entire ALSA buffer */
+ max_urbs = min((unsigned) MAX_URBS,
+ MAX_QUEUE * packs_per_ms / urb_packs);
+ ep->nurbs = min(max_urbs, urbs_per_period * periods_per_buffer);
+ }
+
+ /* allocate and initialize data urbs */
+ for (i = 0; i < ep->nurbs; i++) {
+ struct snd_urb_ctx *u = &ep->urb[i];
+ u->index = i;
+ u->ep = ep;
+ u->packets = urb_packs;
+ u->buffer_size = maxsize * u->packets;
+
+ if (fmt->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(ep->chip->dev, u->buffer_size,
+ GFP_KERNEL, &u->urb->transfer_dma);
+ if (!u->urb->transfer_buffer)
+ goto out_of_memory;
+ u->urb->pipe = ep->pipe;
+ u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
+ u->urb->interval = 1 << ep->datainterval;
+ u->urb->context = u;
+ u->urb->complete = snd_complete_urb;
+ INIT_LIST_HEAD(&u->ready_list);
+ }
+
+ return 0;
+
+out_of_memory:
+ release_urbs(ep, 0);
+ return -ENOMEM;
+}
+
+/*
+ * configure a sync endpoint
+ */
+static int sync_ep_set_params(struct snd_usb_endpoint *ep)
+{
+ int i;
+
+ ep->syncbuf = usb_alloc_coherent(ep->chip->dev, SYNC_URBS * 4,
+ GFP_KERNEL, &ep->sync_dma);
+ if (!ep->syncbuf)
+ return -ENOMEM;
+
+ for (i = 0; i < SYNC_URBS; i++) {
+ struct snd_urb_ctx *u = &ep->urb[i];
+ u->index = i;
+ u->ep = ep;
+ u->packets = 1;
+ u->urb = usb_alloc_urb(1, GFP_KERNEL);
+ if (!u->urb)
+ goto out_of_memory;
+ u->urb->transfer_buffer = ep->syncbuf + i * 4;
+ u->urb->transfer_dma = ep->sync_dma + i * 4;
+ u->urb->transfer_buffer_length = 4;
+ u->urb->pipe = ep->pipe;
+ u->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
+ u->urb->number_of_packets = 1;
+ u->urb->interval = 1 << ep->syncinterval;
+ u->urb->context = u;
+ u->urb->complete = snd_complete_urb;
+ }
+
+ ep->nurbs = SYNC_URBS;
+
+ return 0;
+
+out_of_memory:
+ release_urbs(ep, 0);
+ return -ENOMEM;
+}
+
+/**
+ * snd_usb_endpoint_set_params: configure an snd_usb_endpoint
+ *
+ * @ep: the snd_usb_endpoint to configure
+ * @pcm_format: the audio fomat.
+ * @channels: the number of audio channels.
+ * @period_bytes: the number of bytes in one alsa period.
+ * @period_frames: the number of frames in one alsa period.
+ * @buffer_periods: the number of periods in one alsa buffer.
+ * @rate: the frame rate.
+ * @fmt: the USB audio format information
+ * @sync_ep: the sync endpoint to use, if any
+ *
+ * Determine the number of URBs to be used on this endpoint.
+ * An endpoint must be configured before it can be started.
+ * An endpoint that is already running can not be reconfigured.
+ */
+int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
+ snd_pcm_format_t pcm_format,
+ unsigned int channels,
+ unsigned int period_bytes,
+ unsigned int period_frames,
+ unsigned int buffer_periods,
+ unsigned int rate,
+ struct audioformat *fmt,
+ struct snd_usb_endpoint *sync_ep)
+{
+ int err;
+
+ if (ep->use_count != 0) {
+ usb_audio_warn(ep->chip,
+ "Unable to change format on ep #%x: already in use\n",
+ ep->ep_num);
+ return -EBUSY;
+ }
+
+ /* release old buffers, if any */
+ release_urbs(ep, 0);
+
+ ep->datainterval = fmt->datainterval;
+ ep->maxpacksize = fmt->maxpacksize;
+ ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
+
+ if (snd_usb_get_speed(ep->chip->dev) == USB_SPEED_FULL)
+ ep->freqn = get_usb_full_speed_rate(rate);
+ else
+ ep->freqn = get_usb_high_speed_rate(rate);
+
+ /* calculate the frequency in 16.16 format */
+ ep->freqm = ep->freqn;
+ ep->freqshift = INT_MIN;
+
+ ep->phase = 0;
+
+ switch (ep->type) {
+ case SND_USB_ENDPOINT_TYPE_DATA:
+ err = data_ep_set_params(ep, pcm_format, channels,
+ period_bytes, period_frames,
+ buffer_periods, fmt, sync_ep);
+ break;
+ case SND_USB_ENDPOINT_TYPE_SYNC:
+ err = sync_ep_set_params(ep);
+ break;
+ default:
+ err = -EINVAL;
+ }
+
+ usb_audio_dbg(ep->chip,
+ "Setting params for ep #%x (type %d, %d urbs), ret=%d\n",
+ ep->ep_num, ep->type, ep->nurbs, err);
+
+ return err;
+}
+
+/**
+ * snd_usb_endpoint_start: start an snd_usb_endpoint
+ *
+ * @ep: the endpoint to start
+ *
+ * A call to this function will increment the use count of the endpoint.
+ * In case it is not already running, the URBs for this endpoint will be
+ * submitted. Otherwise, this function does nothing.
+ *
+ * Must be balanced to calls of snd_usb_endpoint_stop().
+ *
+ * Returns an error if the URB submission failed, 0 in all other cases.
+ */
+int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
+{
+ int err;
+ unsigned int i;
+
+ if (atomic_read(&ep->chip->shutdown))
+ return -EBADFD;
+
+ /* already running? */
+ if (++ep->use_count != 1)
+ return 0;
+
+ /* just to be sure */
+ deactivate_urbs(ep, false);
+
+ ep->active_mask = 0;
+ ep->unlink_mask = 0;
+ ep->phase = 0;
+
+ snd_usb_endpoint_start_quirk(ep);
+
+ /*
+ * If this endpoint has a data endpoint as implicit feedback source,
+ * don't start the urbs here. Instead, mark them all as available,
+ * wait for the record urbs to return and queue the playback urbs
+ * from that context.
+ */
+
+ set_bit(EP_FLAG_RUNNING, &ep->flags);
+
+ if (snd_usb_endpoint_implicit_feedback_sink(ep)) {
+ for (i = 0; i < ep->nurbs; i++) {
+ struct snd_urb_ctx *ctx = ep->urb + i;
+ list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
+ }
+
+ return 0;
+ }
+
+ for (i = 0; i < ep->nurbs; i++) {
+ struct urb *urb = ep->urb[i].urb;
+
+ if (snd_BUG_ON(!urb))
+ goto __error;
+
+ if (usb_pipeout(ep->pipe)) {
+ prepare_outbound_urb(ep, urb->context);
+ } else {
+ prepare_inbound_urb(ep, urb->context);
+ }
+
+ err = usb_submit_urb(urb, GFP_ATOMIC);
+ if (err < 0) {
+ usb_audio_err(ep->chip,
+ "cannot submit urb %d, error %d: %s\n",
+ i, err, usb_error_string(err));
+ goto __error;
+ }
+ set_bit(i, &ep->active_mask);
+ }
+
+ return 0;
+
+__error:
+ clear_bit(EP_FLAG_RUNNING, &ep->flags);
+ ep->use_count--;
+ deactivate_urbs(ep, false);
+ return -EPIPE;
+}
+
+/**
+ * snd_usb_endpoint_stop: stop an snd_usb_endpoint
+ *
+ * @ep: the endpoint to stop (may be NULL)
+ *
+ * A call to this function will decrement the use count of the endpoint.
+ * In case the last user has requested the endpoint stop, the URBs will
+ * actually be deactivated.
+ *
+ * Must be balanced to calls of snd_usb_endpoint_start().
+ *
+ * The caller needs to synchronize the pending stop operation via
+ * snd_usb_endpoint_sync_pending_stop().
+ */
+void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep)
+{
+ if (!ep)
+ return;
+
+ if (snd_BUG_ON(ep->use_count == 0))
+ return;
+
+ if (--ep->use_count == 0) {
+ deactivate_urbs(ep, false);
+ set_bit(EP_FLAG_STOPPING, &ep->flags);
+ }
+}
+
+/**
+ * snd_usb_endpoint_deactivate: deactivate an snd_usb_endpoint
+ *
+ * @ep: the endpoint to deactivate
+ *
+ * If the endpoint is not currently in use, this functions will
+ * deactivate its associated URBs.
+ *
+ * In case of any active users, this functions does nothing.
+ */
+void snd_usb_endpoint_deactivate(struct snd_usb_endpoint *ep)
+{
+ if (!ep)
+ return;
+
+ if (ep->use_count != 0)
+ return;
+
+ deactivate_urbs(ep, true);
+ wait_clear_urbs(ep);
+}
+
+/**
+ * snd_usb_endpoint_release: Tear down an snd_usb_endpoint
+ *
+ * @ep: the endpoint to release
+ *
+ * This function does not care for the endpoint's use count but will tear
+ * down all the streaming URBs immediately.
+ */
+void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
+{
+ release_urbs(ep, 1);
+}
+
+/**
+ * snd_usb_endpoint_free: Free the resources of an snd_usb_endpoint
+ *
+ * @ep: the endpoint to free
+ *
+ * This free all resources of the given ep.
+ */
+void snd_usb_endpoint_free(struct snd_usb_endpoint *ep)
+{
+ kfree(ep);
+}
+
+/**
+ * snd_usb_handle_sync_urb: parse an USB sync packet
+ *
+ * @ep: the endpoint to handle the packet
+ * @sender: the sending endpoint
+ * @urb: the received packet
+ *
+ * This function is called from the context of an endpoint that received
+ * the packet and is used to let another endpoint object handle the payload.
+ */
+void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
+ struct snd_usb_endpoint *sender,
+ const struct urb *urb)
+{
+ int shift;
+ unsigned int f;
+ unsigned long flags;
+
+ snd_BUG_ON(ep == sender);
+
+ /*
+ * In case the endpoint is operating in implicit feedback mode, prepare
+ * a new outbound URB that has the same layout as the received packet
+ * and add it to the list of pending urbs. queue_pending_output_urbs()
+ * will take care of them later.
+ */
+ if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
+ ep->use_count != 0) {
+
+ /* implicit feedback case */
+ int i, bytes = 0;
+ struct snd_urb_ctx *in_ctx;
+ struct snd_usb_packet_info *out_packet;
+
+ in_ctx = urb->context;
+
+ /* Count overall packet size */
+ for (i = 0; i < in_ctx->packets; i++)
+ if (urb->iso_frame_desc[i].status == 0)
+ bytes += urb->iso_frame_desc[i].actual_length;
+
+ /*
+ * skip empty packets. At least M-Audio's Fast Track Ultra stops
+ * streaming once it received a 0-byte OUT URB
+ */
+ if (bytes == 0)
+ return;
+
+ spin_lock_irqsave(&ep->lock, flags);
+ out_packet = ep->next_packet + ep->next_packet_write_pos;
+
+ /*
+ * Iterate through the inbound packet and prepare the lengths
+ * for the output packet. The OUT packet we are about to send
+ * will have the same amount of payload bytes per stride as the
+ * IN packet we just received. Since the actual size is scaled
+ * by the stride, use the sender stride to calculate the length
+ * in case the number of channels differ between the implicitly
+ * fed-back endpoint and the synchronizing endpoint.
+ */
+
+ out_packet->packets = in_ctx->packets;
+ for (i = 0; i < in_ctx->packets; i++) {
+ if (urb->iso_frame_desc[i].status == 0)
+ out_packet->packet_size[i] =
+ urb->iso_frame_desc[i].actual_length / sender->stride;
+ else
+ out_packet->packet_size[i] = 0;
+ }
+
+ ep->next_packet_write_pos++;
+ ep->next_packet_write_pos %= MAX_URBS;
+ spin_unlock_irqrestore(&ep->lock, flags);
+ queue_pending_output_urbs(ep);
+
+ return;
+ }
+
+ /*
+ * 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.
+ */
+
+ if (urb->iso_frame_desc[0].status != 0 ||
+ urb->iso_frame_desc[0].actual_length < 3)
+ return;
+
+ 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;
+
+ if (unlikely(sender->tenor_fb_quirk)) {
+ /*
+ * Devices based on Tenor 8802 chipsets (TEAC UD-H01
+ * and others) sometimes change the feedback value
+ * by +/- 0x1.0000.
+ */
+ if (f < ep->freqn - 0x8000)
+ f += 0xf000;
+ else if (f > ep->freqn + 0x8000)
+ f -= 0xf000;
+ } else if (unlikely(ep->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 < ep->freqn - ep->freqn / 4) {
+ f <<= 1;
+ shift++;
+ }
+ while (f > ep->freqn + ep->freqn / 2) {
+ f >>= 1;
+ shift--;
+ }
+ ep->freqshift = shift;
+ } else if (ep->freqshift >= 0)
+ f <<= ep->freqshift;
+ else
+ f >>= -ep->freqshift;
+
+ if (likely(f >= ep->freqn - ep->freqn / 8 && f <= ep->freqmax)) {
+ /*
+ * If the frequency looks valid, set it.
+ * This value is referred to in prepare_playback_urb().
+ */
+ spin_lock_irqsave(&ep->lock, flags);
+ ep->freqm = f;
+ spin_unlock_irqrestore(&ep->lock, flags);
+ } else {
+ /*
+ * Out of range; maybe the shift value is wrong.
+ * Reset it so that we autodetect again the next time.
+ */
+ ep->freqshift = INT_MIN;
+ }
+}
+