1893 lines
48 KiB
C
1893 lines
48 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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*/
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#include <linux/gfp.h>
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#include <linux/init.h>
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#include <linux/ratelimit.h>
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#include <linux/usb.h>
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#include <linux/usb/audio.h>
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#include <linux/slab.h>
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#include <sound/core.h>
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#include <sound/pcm.h>
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#include <sound/pcm_params.h>
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#include "usbaudio.h"
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#include "helper.h"
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#include "card.h"
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#include "endpoint.h"
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#include "pcm.h"
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#include "clock.h"
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#include "quirks.h"
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enum {
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EP_STATE_STOPPED,
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EP_STATE_RUNNING,
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EP_STATE_STOPPING,
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};
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/* interface refcounting */
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struct snd_usb_iface_ref {
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unsigned char iface;
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bool need_setup;
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int opened;
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int altset;
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struct list_head list;
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};
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/* clock refcounting */
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struct snd_usb_clock_ref {
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unsigned char clock;
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atomic_t locked;
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int opened;
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int rate;
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bool need_setup;
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struct list_head list;
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};
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/*
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* snd_usb_endpoint is a model that abstracts everything related to an
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* USB endpoint and its streaming.
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*
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* There are functions to activate and deactivate the streaming URBs and
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* optional callbacks to let the pcm logic handle the actual content of the
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* packets for playback and record. Thus, the bus streaming and the audio
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* handlers are fully decoupled.
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*
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* There are two different types of endpoints in audio applications.
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*
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* SND_USB_ENDPOINT_TYPE_DATA handles full audio data payload for both
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* inbound and outbound traffic.
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*
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* SND_USB_ENDPOINT_TYPE_SYNC endpoints are for inbound traffic only and
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* expect the payload to carry Q10.14 / Q16.16 formatted sync information
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* (3 or 4 bytes).
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*
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* Each endpoint has to be configured prior to being used by calling
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* snd_usb_endpoint_set_params().
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*
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* The model incorporates a reference counting, so that multiple users
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* can call snd_usb_endpoint_start() and snd_usb_endpoint_stop(), and
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* only the first user will effectively start the URBs, and only the last
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* one to stop it will tear the URBs down again.
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*/
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/*
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* convert a sampling rate into our full speed format (fs/1000 in Q16.16)
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* this will overflow at approx 524 kHz
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*/
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static inline unsigned get_usb_full_speed_rate(unsigned int rate)
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{
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return ((rate << 13) + 62) / 125;
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}
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/*
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* convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
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* this will overflow at approx 4 MHz
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*/
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static inline unsigned get_usb_high_speed_rate(unsigned int rate)
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{
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return ((rate << 10) + 62) / 125;
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}
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/*
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* release a urb data
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*/
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static void release_urb_ctx(struct snd_urb_ctx *u)
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{
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if (u->urb && u->buffer_size)
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usb_free_coherent(u->ep->chip->dev, u->buffer_size,
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u->urb->transfer_buffer,
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u->urb->transfer_dma);
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usb_free_urb(u->urb);
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u->urb = NULL;
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u->buffer_size = 0;
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}
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static const char *usb_error_string(int err)
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{
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switch (err) {
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case -ENODEV:
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return "no device";
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case -ENOENT:
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return "endpoint not enabled";
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case -EPIPE:
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return "endpoint stalled";
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case -ENOSPC:
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return "not enough bandwidth";
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case -ESHUTDOWN:
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return "device disabled";
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case -EHOSTUNREACH:
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return "device suspended";
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case -EINVAL:
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case -EAGAIN:
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case -EFBIG:
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case -EMSGSIZE:
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return "internal error";
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default:
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return "unknown error";
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}
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}
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static inline bool ep_state_running(struct snd_usb_endpoint *ep)
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{
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return atomic_read(&ep->state) == EP_STATE_RUNNING;
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}
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static inline bool ep_state_update(struct snd_usb_endpoint *ep, int old, int new)
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{
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return atomic_try_cmpxchg(&ep->state, &old, new);
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}
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/**
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* snd_usb_endpoint_implicit_feedback_sink: Report endpoint usage type
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*
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* @ep: The snd_usb_endpoint
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*
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* Determine whether an endpoint is driven by an implicit feedback
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* data endpoint source.
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*/
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int snd_usb_endpoint_implicit_feedback_sink(struct snd_usb_endpoint *ep)
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{
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return ep->implicit_fb_sync && usb_pipeout(ep->pipe);
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}
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/*
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* Return the number of samples to be sent in the next packet
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* for streaming based on information derived from sync endpoints
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*
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* This won't be used for implicit feedback which takes the packet size
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* returned from the sync source
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*/
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static int slave_next_packet_size(struct snd_usb_endpoint *ep,
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unsigned int avail)
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{
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unsigned long flags;
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unsigned int phase;
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int ret;
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if (ep->fill_max)
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return ep->maxframesize;
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spin_lock_irqsave(&ep->lock, flags);
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phase = (ep->phase & 0xffff) + (ep->freqm << ep->datainterval);
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ret = min(phase >> 16, ep->maxframesize);
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if (avail && ret >= avail)
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ret = -EAGAIN;
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else
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ep->phase = phase;
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spin_unlock_irqrestore(&ep->lock, flags);
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return ret;
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}
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/*
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* Return the number of samples to be sent in the next packet
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* for adaptive and synchronous endpoints
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*/
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static int next_packet_size(struct snd_usb_endpoint *ep, unsigned int avail)
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{
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unsigned int sample_accum;
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int ret;
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if (ep->fill_max)
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return ep->maxframesize;
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sample_accum = ep->sample_accum + ep->sample_rem;
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if (sample_accum >= ep->pps) {
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sample_accum -= ep->pps;
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ret = ep->packsize[1];
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} else {
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ret = ep->packsize[0];
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}
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if (avail && ret >= avail)
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ret = -EAGAIN;
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else
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ep->sample_accum = sample_accum;
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return ret;
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}
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/*
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* snd_usb_endpoint_next_packet_size: Return the number of samples to be sent
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* in the next packet
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*
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* If the size is equal or exceeds @avail, don't proceed but return -EAGAIN
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* Exception: @avail = 0 for skipping the check.
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*/
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int snd_usb_endpoint_next_packet_size(struct snd_usb_endpoint *ep,
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struct snd_urb_ctx *ctx, int idx,
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unsigned int avail)
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{
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unsigned int packet;
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packet = ctx->packet_size[idx];
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if (packet) {
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if (avail && packet >= avail)
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return -EAGAIN;
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return packet;
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}
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if (ep->sync_source)
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return slave_next_packet_size(ep, avail);
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else
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return next_packet_size(ep, avail);
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}
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static void call_retire_callback(struct snd_usb_endpoint *ep,
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struct urb *urb)
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{
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struct snd_usb_substream *data_subs;
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data_subs = READ_ONCE(ep->data_subs);
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if (data_subs && ep->retire_data_urb)
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ep->retire_data_urb(data_subs, urb);
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}
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static void retire_outbound_urb(struct snd_usb_endpoint *ep,
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struct snd_urb_ctx *urb_ctx)
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{
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call_retire_callback(ep, urb_ctx->urb);
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}
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static void snd_usb_handle_sync_urb(struct snd_usb_endpoint *ep,
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struct snd_usb_endpoint *sender,
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const struct urb *urb);
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static void retire_inbound_urb(struct snd_usb_endpoint *ep,
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struct snd_urb_ctx *urb_ctx)
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{
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struct urb *urb = urb_ctx->urb;
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struct snd_usb_endpoint *sync_sink;
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if (unlikely(ep->skip_packets > 0)) {
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ep->skip_packets--;
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return;
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}
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sync_sink = READ_ONCE(ep->sync_sink);
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if (sync_sink)
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snd_usb_handle_sync_urb(sync_sink, ep, urb);
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call_retire_callback(ep, urb);
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}
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static inline bool has_tx_length_quirk(struct snd_usb_audio *chip)
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{
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return chip->quirk_flags & QUIRK_FLAG_TX_LENGTH;
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}
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static void prepare_silent_urb(struct snd_usb_endpoint *ep,
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struct snd_urb_ctx *ctx)
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{
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struct urb *urb = ctx->urb;
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unsigned int offs = 0;
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unsigned int extra = 0;
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__le32 packet_length;
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int i;
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/* For tx_length_quirk, put packet length at start of packet */
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if (has_tx_length_quirk(ep->chip))
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extra = sizeof(packet_length);
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for (i = 0; i < ctx->packets; ++i) {
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unsigned int offset;
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unsigned int length;
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int counts;
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counts = snd_usb_endpoint_next_packet_size(ep, ctx, i, 0);
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length = counts * ep->stride; /* number of silent bytes */
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offset = offs * ep->stride + extra * i;
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urb->iso_frame_desc[i].offset = offset;
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urb->iso_frame_desc[i].length = length + extra;
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if (extra) {
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packet_length = cpu_to_le32(length);
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memcpy(urb->transfer_buffer + offset,
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&packet_length, sizeof(packet_length));
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}
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memset(urb->transfer_buffer + offset + extra,
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ep->silence_value, length);
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offs += counts;
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}
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urb->number_of_packets = ctx->packets;
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urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra;
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ctx->queued = 0;
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}
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/*
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* Prepare a PLAYBACK urb for submission to the bus.
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*/
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static int prepare_outbound_urb(struct snd_usb_endpoint *ep,
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struct snd_urb_ctx *ctx,
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bool in_stream_lock)
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{
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struct urb *urb = ctx->urb;
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unsigned char *cp = urb->transfer_buffer;
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struct snd_usb_substream *data_subs;
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urb->dev = ep->chip->dev; /* we need to set this at each time */
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switch (ep->type) {
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case SND_USB_ENDPOINT_TYPE_DATA:
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data_subs = READ_ONCE(ep->data_subs);
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if (data_subs && ep->prepare_data_urb)
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return ep->prepare_data_urb(data_subs, urb, in_stream_lock);
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/* no data provider, so send silence */
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prepare_silent_urb(ep, ctx);
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break;
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case SND_USB_ENDPOINT_TYPE_SYNC:
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if (snd_usb_get_speed(ep->chip->dev) >= USB_SPEED_HIGH) {
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/*
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* fill the length and offset of each urb descriptor.
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* the fixed 12.13 frequency is passed as 16.16 through the pipe.
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*/
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urb->iso_frame_desc[0].length = 4;
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urb->iso_frame_desc[0].offset = 0;
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cp[0] = ep->freqn;
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cp[1] = ep->freqn >> 8;
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cp[2] = ep->freqn >> 16;
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cp[3] = ep->freqn >> 24;
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} else {
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/*
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* fill the length and offset of each urb descriptor.
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* the fixed 10.14 frequency is passed through the pipe.
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*/
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urb->iso_frame_desc[0].length = 3;
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urb->iso_frame_desc[0].offset = 0;
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cp[0] = ep->freqn >> 2;
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cp[1] = ep->freqn >> 10;
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cp[2] = ep->freqn >> 18;
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}
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break;
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}
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return 0;
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}
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/*
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* Prepare a CAPTURE or SYNC urb for submission to the bus.
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*/
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static int prepare_inbound_urb(struct snd_usb_endpoint *ep,
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struct snd_urb_ctx *urb_ctx)
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{
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int i, offs;
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struct urb *urb = urb_ctx->urb;
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urb->dev = ep->chip->dev; /* we need to set this at each time */
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switch (ep->type) {
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case SND_USB_ENDPOINT_TYPE_DATA:
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offs = 0;
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for (i = 0; i < urb_ctx->packets; i++) {
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urb->iso_frame_desc[i].offset = offs;
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urb->iso_frame_desc[i].length = ep->curpacksize;
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offs += ep->curpacksize;
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}
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urb->transfer_buffer_length = offs;
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urb->number_of_packets = urb_ctx->packets;
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break;
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case SND_USB_ENDPOINT_TYPE_SYNC:
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urb->iso_frame_desc[0].length = min(4u, ep->syncmaxsize);
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urb->iso_frame_desc[0].offset = 0;
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break;
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}
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return 0;
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}
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/* notify an error as XRUN to the assigned PCM data substream */
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static void notify_xrun(struct snd_usb_endpoint *ep)
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{
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struct snd_usb_substream *data_subs;
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data_subs = READ_ONCE(ep->data_subs);
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if (data_subs && data_subs->pcm_substream)
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snd_pcm_stop_xrun(data_subs->pcm_substream);
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}
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static struct snd_usb_packet_info *
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next_packet_fifo_enqueue(struct snd_usb_endpoint *ep)
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{
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struct snd_usb_packet_info *p;
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p = ep->next_packet + (ep->next_packet_head + ep->next_packet_queued) %
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ARRAY_SIZE(ep->next_packet);
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ep->next_packet_queued++;
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return p;
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}
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static struct snd_usb_packet_info *
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next_packet_fifo_dequeue(struct snd_usb_endpoint *ep)
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{
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struct snd_usb_packet_info *p;
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p = ep->next_packet + ep->next_packet_head;
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ep->next_packet_head++;
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ep->next_packet_head %= ARRAY_SIZE(ep->next_packet);
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ep->next_packet_queued--;
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return p;
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}
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static void push_back_to_ready_list(struct snd_usb_endpoint *ep,
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struct snd_urb_ctx *ctx)
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{
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unsigned long flags;
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spin_lock_irqsave(&ep->lock, flags);
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list_add_tail(&ctx->ready_list, &ep->ready_playback_urbs);
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spin_unlock_irqrestore(&ep->lock, flags);
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}
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/*
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* Send output urbs that have been prepared previously. URBs are dequeued
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* from ep->ready_playback_urbs and in case there aren't any available
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* or there are no packets that have been prepared, this function does
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* nothing.
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*
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* The reason why the functionality of sending and preparing URBs is separated
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* is that host controllers don't guarantee the order in which they return
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* inbound and outbound packets to their submitters.
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*
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* This function is used both for implicit feedback endpoints and in low-
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* latency playback mode.
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*/
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int snd_usb_queue_pending_output_urbs(struct snd_usb_endpoint *ep,
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bool in_stream_lock)
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{
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bool implicit_fb = snd_usb_endpoint_implicit_feedback_sink(ep);
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while (ep_state_running(ep)) {
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unsigned long flags;
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struct snd_usb_packet_info *packet;
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struct snd_urb_ctx *ctx = NULL;
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int err, i;
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spin_lock_irqsave(&ep->lock, flags);
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if ((!implicit_fb || ep->next_packet_queued > 0) &&
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!list_empty(&ep->ready_playback_urbs)) {
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/* take URB out of FIFO */
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ctx = list_first_entry(&ep->ready_playback_urbs,
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struct snd_urb_ctx, ready_list);
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list_del_init(&ctx->ready_list);
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if (implicit_fb)
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packet = next_packet_fifo_dequeue(ep);
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}
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spin_unlock_irqrestore(&ep->lock, flags);
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if (ctx == NULL)
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break;
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/* copy over the length information */
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if (implicit_fb) {
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for (i = 0; i < packet->packets; i++)
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ctx->packet_size[i] = packet->packet_size[i];
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}
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/* call the data handler to fill in playback data */
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err = prepare_outbound_urb(ep, ctx, in_stream_lock);
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/* can be stopped during prepare callback */
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if (unlikely(!ep_state_running(ep)))
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break;
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if (err < 0) {
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/* push back to ready list again for -EAGAIN */
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if (err == -EAGAIN) {
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push_back_to_ready_list(ep, ctx);
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break;
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}
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if (!in_stream_lock)
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notify_xrun(ep);
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return -EPIPE;
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}
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err = usb_submit_urb(ctx->urb, GFP_ATOMIC);
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if (err < 0) {
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usb_audio_err(ep->chip,
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"Unable to submit urb #%d: %d at %s\n",
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ctx->index, err, __func__);
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if (!in_stream_lock)
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notify_xrun(ep);
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return -EPIPE;
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}
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set_bit(ctx->index, &ep->active_mask);
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atomic_inc(&ep->submitted_urbs);
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}
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return 0;
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}
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|
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/*
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* complete callback for urbs
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*/
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static void snd_complete_urb(struct urb *urb)
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{
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struct snd_urb_ctx *ctx = urb->context;
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struct snd_usb_endpoint *ep = ctx->ep;
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int err;
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if (unlikely(urb->status == -ENOENT || /* unlinked */
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|
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(!ep_state_running(ep)))
|
|
goto exit_clear;
|
|
|
|
if (usb_pipeout(ep->pipe)) {
|
|
retire_outbound_urb(ep, ctx);
|
|
/* can be stopped during retire callback */
|
|
if (unlikely(!ep_state_running(ep)))
|
|
goto exit_clear;
|
|
|
|
/* in low-latency and implicit-feedback modes, push back the
|
|
* URB to ready list at first, then process as much as possible
|
|
*/
|
|
if (ep->lowlatency_playback ||
|
|
snd_usb_endpoint_implicit_feedback_sink(ep)) {
|
|
push_back_to_ready_list(ep, ctx);
|
|
clear_bit(ctx->index, &ep->active_mask);
|
|
snd_usb_queue_pending_output_urbs(ep, false);
|
|
atomic_dec(&ep->submitted_urbs); /* decrement at last */
|
|
return;
|
|
}
|
|
|
|
/* in non-lowlatency mode, no error handling for prepare */
|
|
prepare_outbound_urb(ep, ctx, false);
|
|
/* can be stopped during prepare callback */
|
|
if (unlikely(!ep_state_running(ep)))
|
|
goto exit_clear;
|
|
} else {
|
|
retire_inbound_urb(ep, ctx);
|
|
/* can be stopped during retire callback */
|
|
if (unlikely(!ep_state_running(ep)))
|
|
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);
|
|
notify_xrun(ep);
|
|
|
|
exit_clear:
|
|
clear_bit(ctx->index, &ep->active_mask);
|
|
atomic_dec(&ep->submitted_urbs);
|
|
}
|
|
|
|
/*
|
|
* Find or create a refcount object for the given interface
|
|
*
|
|
* The objects are released altogether in snd_usb_endpoint_free_all()
|
|
*/
|
|
static struct snd_usb_iface_ref *
|
|
iface_ref_find(struct snd_usb_audio *chip, int iface)
|
|
{
|
|
struct snd_usb_iface_ref *ip;
|
|
|
|
list_for_each_entry(ip, &chip->iface_ref_list, list)
|
|
if (ip->iface == iface)
|
|
return ip;
|
|
|
|
ip = kzalloc(sizeof(*ip), GFP_KERNEL);
|
|
if (!ip)
|
|
return NULL;
|
|
ip->iface = iface;
|
|
list_add_tail(&ip->list, &chip->iface_ref_list);
|
|
return ip;
|
|
}
|
|
|
|
/* Similarly, a refcount object for clock */
|
|
static struct snd_usb_clock_ref *
|
|
clock_ref_find(struct snd_usb_audio *chip, int clock)
|
|
{
|
|
struct snd_usb_clock_ref *ref;
|
|
|
|
list_for_each_entry(ref, &chip->clock_ref_list, list)
|
|
if (ref->clock == clock)
|
|
return ref;
|
|
|
|
ref = kzalloc(sizeof(*ref), GFP_KERNEL);
|
|
if (!ref)
|
|
return NULL;
|
|
ref->clock = clock;
|
|
atomic_set(&ref->locked, 0);
|
|
list_add_tail(&ref->list, &chip->clock_ref_list);
|
|
return ref;
|
|
}
|
|
|
|
/*
|
|
* Get the existing endpoint object corresponding EP
|
|
* Returns NULL if not present.
|
|
*/
|
|
struct snd_usb_endpoint *
|
|
snd_usb_get_endpoint(struct snd_usb_audio *chip, int ep_num)
|
|
{
|
|
struct snd_usb_endpoint *ep;
|
|
|
|
list_for_each_entry(ep, &chip->ep_list, list) {
|
|
if (ep->ep_num == ep_num)
|
|
return ep;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
#define ep_type_name(type) \
|
|
(type == SND_USB_ENDPOINT_TYPE_DATA ? "data" : "sync")
|
|
|
|
/**
|
|
* snd_usb_add_endpoint: Add an endpoint to an USB audio chip
|
|
*
|
|
* @chip: The chip
|
|
* @ep_num: The number of the endpoint to use
|
|
* @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.
|
|
*
|
|
* Returns zero on success or a negative error code.
|
|
*
|
|
* New endpoints will be added to chip->ep_list and freed by
|
|
* calling snd_usb_endpoint_free_all().
|
|
*
|
|
* For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that
|
|
* bNumEndpoints > 1 beforehand.
|
|
*/
|
|
int snd_usb_add_endpoint(struct snd_usb_audio *chip, int ep_num, int type)
|
|
{
|
|
struct snd_usb_endpoint *ep;
|
|
bool is_playback;
|
|
|
|
ep = snd_usb_get_endpoint(chip, ep_num);
|
|
if (ep)
|
|
return 0;
|
|
|
|
usb_audio_dbg(chip, "Creating new %s endpoint #%x\n",
|
|
ep_type_name(type),
|
|
ep_num);
|
|
ep = kzalloc(sizeof(*ep), GFP_KERNEL);
|
|
if (!ep)
|
|
return -ENOMEM;
|
|
|
|
ep->chip = chip;
|
|
spin_lock_init(&ep->lock);
|
|
ep->type = type;
|
|
ep->ep_num = ep_num;
|
|
INIT_LIST_HEAD(&ep->ready_playback_urbs);
|
|
atomic_set(&ep->submitted_urbs, 0);
|
|
|
|
is_playback = ((ep_num & USB_ENDPOINT_DIR_MASK) == USB_DIR_OUT);
|
|
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);
|
|
|
|
list_add_tail(&ep->list, &chip->ep_list);
|
|
return 0;
|
|
}
|
|
|
|
/* Set up syncinterval and maxsyncsize for a sync EP */
|
|
static void endpoint_set_syncinterval(struct snd_usb_audio *chip,
|
|
struct snd_usb_endpoint *ep)
|
|
{
|
|
struct usb_host_interface *alts;
|
|
struct usb_endpoint_descriptor *desc;
|
|
|
|
alts = snd_usb_get_host_interface(chip, ep->iface, ep->altsetting);
|
|
if (!alts)
|
|
return;
|
|
|
|
desc = get_endpoint(alts, ep->ep_idx);
|
|
if (desc->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE &&
|
|
desc->bRefresh >= 1 && desc->bRefresh <= 9)
|
|
ep->syncinterval = desc->bRefresh;
|
|
else if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL)
|
|
ep->syncinterval = 1;
|
|
else if (desc->bInterval >= 1 && desc->bInterval <= 16)
|
|
ep->syncinterval = desc->bInterval - 1;
|
|
else
|
|
ep->syncinterval = 3;
|
|
|
|
ep->syncmaxsize = le16_to_cpu(desc->wMaxPacketSize);
|
|
}
|
|
|
|
static bool endpoint_compatible(struct snd_usb_endpoint *ep,
|
|
const struct audioformat *fp,
|
|
const struct snd_pcm_hw_params *params)
|
|
{
|
|
if (!ep->opened)
|
|
return false;
|
|
if (ep->cur_audiofmt != fp)
|
|
return false;
|
|
if (ep->cur_rate != params_rate(params) ||
|
|
ep->cur_format != params_format(params) ||
|
|
ep->cur_period_frames != params_period_size(params) ||
|
|
ep->cur_buffer_periods != params_periods(params))
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Check whether the given fp and hw params are compatible with the current
|
|
* setup of the target EP for implicit feedback sync
|
|
*/
|
|
bool snd_usb_endpoint_compatible(struct snd_usb_audio *chip,
|
|
struct snd_usb_endpoint *ep,
|
|
const struct audioformat *fp,
|
|
const struct snd_pcm_hw_params *params)
|
|
{
|
|
bool ret;
|
|
|
|
mutex_lock(&chip->mutex);
|
|
ret = endpoint_compatible(ep, fp, params);
|
|
mutex_unlock(&chip->mutex);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* snd_usb_endpoint_open: Open the endpoint
|
|
*
|
|
* Called from hw_params to assign the endpoint to the substream.
|
|
* It's reference-counted, and only the first opener is allowed to set up
|
|
* arbitrary parameters. The later opener must be compatible with the
|
|
* former opened parameters.
|
|
* The endpoint needs to be closed via snd_usb_endpoint_close() later.
|
|
*
|
|
* Note that this function doesn't configure the endpoint. The substream
|
|
* needs to set it up later via snd_usb_endpoint_set_params() and
|
|
* snd_usb_endpoint_prepare().
|
|
*/
|
|
struct snd_usb_endpoint *
|
|
snd_usb_endpoint_open(struct snd_usb_audio *chip,
|
|
const struct audioformat *fp,
|
|
const struct snd_pcm_hw_params *params,
|
|
bool is_sync_ep,
|
|
bool fixed_rate)
|
|
{
|
|
struct snd_usb_endpoint *ep;
|
|
int ep_num = is_sync_ep ? fp->sync_ep : fp->endpoint;
|
|
|
|
mutex_lock(&chip->mutex);
|
|
ep = snd_usb_get_endpoint(chip, ep_num);
|
|
if (!ep) {
|
|
usb_audio_err(chip, "Cannot find EP 0x%x to open\n", ep_num);
|
|
goto unlock;
|
|
}
|
|
|
|
if (!ep->opened) {
|
|
if (is_sync_ep) {
|
|
ep->iface = fp->sync_iface;
|
|
ep->altsetting = fp->sync_altsetting;
|
|
ep->ep_idx = fp->sync_ep_idx;
|
|
} else {
|
|
ep->iface = fp->iface;
|
|
ep->altsetting = fp->altsetting;
|
|
ep->ep_idx = fp->ep_idx;
|
|
}
|
|
usb_audio_dbg(chip, "Open EP 0x%x, iface=%d:%d, idx=%d\n",
|
|
ep_num, ep->iface, ep->altsetting, ep->ep_idx);
|
|
|
|
ep->iface_ref = iface_ref_find(chip, ep->iface);
|
|
if (!ep->iface_ref) {
|
|
ep = NULL;
|
|
goto unlock;
|
|
}
|
|
|
|
if (fp->protocol != UAC_VERSION_1) {
|
|
ep->clock_ref = clock_ref_find(chip, fp->clock);
|
|
if (!ep->clock_ref) {
|
|
ep = NULL;
|
|
goto unlock;
|
|
}
|
|
ep->clock_ref->opened++;
|
|
}
|
|
|
|
ep->cur_audiofmt = fp;
|
|
ep->cur_channels = fp->channels;
|
|
ep->cur_rate = params_rate(params);
|
|
ep->cur_format = params_format(params);
|
|
ep->cur_frame_bytes = snd_pcm_format_physical_width(ep->cur_format) *
|
|
ep->cur_channels / 8;
|
|
ep->cur_period_frames = params_period_size(params);
|
|
ep->cur_period_bytes = ep->cur_period_frames * ep->cur_frame_bytes;
|
|
ep->cur_buffer_periods = params_periods(params);
|
|
|
|
if (ep->type == SND_USB_ENDPOINT_TYPE_SYNC)
|
|
endpoint_set_syncinterval(chip, ep);
|
|
|
|
ep->implicit_fb_sync = fp->implicit_fb;
|
|
ep->need_setup = true;
|
|
ep->need_prepare = true;
|
|
ep->fixed_rate = fixed_rate;
|
|
|
|
usb_audio_dbg(chip, " channels=%d, rate=%d, format=%s, period_bytes=%d, periods=%d, implicit_fb=%d\n",
|
|
ep->cur_channels, ep->cur_rate,
|
|
snd_pcm_format_name(ep->cur_format),
|
|
ep->cur_period_bytes, ep->cur_buffer_periods,
|
|
ep->implicit_fb_sync);
|
|
|
|
} else {
|
|
if (WARN_ON(!ep->iface_ref)) {
|
|
ep = NULL;
|
|
goto unlock;
|
|
}
|
|
|
|
if (!endpoint_compatible(ep, fp, params)) {
|
|
usb_audio_err(chip, "Incompatible EP setup for 0x%x\n",
|
|
ep_num);
|
|
ep = NULL;
|
|
goto unlock;
|
|
}
|
|
|
|
usb_audio_dbg(chip, "Reopened EP 0x%x (count %d)\n",
|
|
ep_num, ep->opened);
|
|
}
|
|
|
|
if (!ep->iface_ref->opened++)
|
|
ep->iface_ref->need_setup = true;
|
|
|
|
ep->opened++;
|
|
|
|
unlock:
|
|
mutex_unlock(&chip->mutex);
|
|
return ep;
|
|
}
|
|
|
|
/*
|
|
* snd_usb_endpoint_set_sync: Link data and sync endpoints
|
|
*
|
|
* Pass NULL to sync_ep to unlink again
|
|
*/
|
|
void snd_usb_endpoint_set_sync(struct snd_usb_audio *chip,
|
|
struct snd_usb_endpoint *data_ep,
|
|
struct snd_usb_endpoint *sync_ep)
|
|
{
|
|
data_ep->sync_source = sync_ep;
|
|
}
|
|
|
|
/*
|
|
* Set data endpoint callbacks and the assigned data stream
|
|
*
|
|
* Called at PCM trigger and cleanups.
|
|
* Pass NULL to deactivate each callback.
|
|
*/
|
|
void snd_usb_endpoint_set_callback(struct snd_usb_endpoint *ep,
|
|
int (*prepare)(struct snd_usb_substream *subs,
|
|
struct urb *urb,
|
|
bool in_stream_lock),
|
|
void (*retire)(struct snd_usb_substream *subs,
|
|
struct urb *urb),
|
|
struct snd_usb_substream *data_subs)
|
|
{
|
|
ep->prepare_data_urb = prepare;
|
|
ep->retire_data_urb = retire;
|
|
if (data_subs)
|
|
ep->lowlatency_playback = data_subs->lowlatency_playback;
|
|
else
|
|
ep->lowlatency_playback = false;
|
|
WRITE_ONCE(ep->data_subs, data_subs);
|
|
}
|
|
|
|
static int endpoint_set_interface(struct snd_usb_audio *chip,
|
|
struct snd_usb_endpoint *ep,
|
|
bool set)
|
|
{
|
|
int altset = set ? ep->altsetting : 0;
|
|
int err;
|
|
|
|
if (ep->iface_ref->altset == altset)
|
|
return 0;
|
|
|
|
usb_audio_dbg(chip, "Setting usb interface %d:%d for EP 0x%x\n",
|
|
ep->iface, altset, ep->ep_num);
|
|
err = usb_set_interface(chip->dev, ep->iface, altset);
|
|
if (err < 0) {
|
|
usb_audio_err(chip, "%d:%d: usb_set_interface failed (%d)\n",
|
|
ep->iface, altset, err);
|
|
return err;
|
|
}
|
|
|
|
if (chip->quirk_flags & QUIRK_FLAG_IFACE_DELAY)
|
|
msleep(50);
|
|
ep->iface_ref->altset = altset;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* snd_usb_endpoint_close: Close the endpoint
|
|
*
|
|
* Unreference the already opened endpoint via snd_usb_endpoint_open().
|
|
*/
|
|
void snd_usb_endpoint_close(struct snd_usb_audio *chip,
|
|
struct snd_usb_endpoint *ep)
|
|
{
|
|
mutex_lock(&chip->mutex);
|
|
usb_audio_dbg(chip, "Closing EP 0x%x (count %d)\n",
|
|
ep->ep_num, ep->opened);
|
|
|
|
if (!--ep->iface_ref->opened &&
|
|
!(chip->quirk_flags & QUIRK_FLAG_IFACE_SKIP_CLOSE))
|
|
endpoint_set_interface(chip, ep, false);
|
|
|
|
if (!--ep->opened) {
|
|
if (ep->clock_ref) {
|
|
if (!--ep->clock_ref->opened)
|
|
ep->clock_ref->rate = 0;
|
|
}
|
|
ep->iface = 0;
|
|
ep->altsetting = 0;
|
|
ep->cur_audiofmt = NULL;
|
|
ep->cur_rate = 0;
|
|
ep->iface_ref = NULL;
|
|
ep->clock_ref = NULL;
|
|
usb_audio_dbg(chip, "EP 0x%x closed\n", ep->ep_num);
|
|
}
|
|
mutex_unlock(&chip->mutex);
|
|
}
|
|
|
|
/* Prepare for suspening EP, called from the main suspend handler */
|
|
void snd_usb_endpoint_suspend(struct snd_usb_endpoint *ep)
|
|
{
|
|
ep->need_prepare = true;
|
|
if (ep->iface_ref)
|
|
ep->iface_ref->need_setup = true;
|
|
if (ep->clock_ref)
|
|
ep->clock_ref->rate = 0;
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
|
|
if (atomic_read(&ep->state) != EP_STATE_STOPPING)
|
|
return 0;
|
|
|
|
do {
|
|
alive = atomic_read(&ep->submitted_urbs);
|
|
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);
|
|
|
|
if (ep_state_update(ep, EP_STATE_STOPPING, EP_STATE_STOPPED)) {
|
|
ep->sync_sink = NULL;
|
|
snd_usb_endpoint_set_callback(ep, NULL, NULL, 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)
|
|
wait_clear_urbs(ep);
|
|
}
|
|
|
|
/*
|
|
* Stop active urbs
|
|
*
|
|
* This function moves the EP to STOPPING state if it's being RUNNING.
|
|
*/
|
|
static int stop_urbs(struct snd_usb_endpoint *ep, bool force, bool keep_pending)
|
|
{
|
|
unsigned int i;
|
|
unsigned long flags;
|
|
|
|
if (!force && atomic_read(&ep->running))
|
|
return -EBUSY;
|
|
|
|
if (!ep_state_update(ep, EP_STATE_RUNNING, EP_STATE_STOPPING))
|
|
return 0;
|
|
|
|
spin_lock_irqsave(&ep->lock, flags);
|
|
INIT_LIST_HEAD(&ep->ready_playback_urbs);
|
|
ep->next_packet_head = 0;
|
|
ep->next_packet_queued = 0;
|
|
spin_unlock_irqrestore(&ep->lock, flags);
|
|
|
|
if (keep_pending)
|
|
return 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 int release_urbs(struct snd_usb_endpoint *ep, bool force)
|
|
{
|
|
int i, err;
|
|
|
|
/* route incoming urbs to nirvana */
|
|
snd_usb_endpoint_set_callback(ep, NULL, NULL, NULL);
|
|
|
|
/* stop and unlink urbs */
|
|
err = stop_urbs(ep, force, false);
|
|
if (err)
|
|
return err;
|
|
|
|
wait_clear_urbs(ep);
|
|
|
|
for (i = 0; i < ep->nurbs; i++)
|
|
release_urb_ctx(&ep->urb[i]);
|
|
|
|
usb_free_coherent(ep->chip->dev, SYNC_URBS * 4,
|
|
ep->syncbuf, ep->sync_dma);
|
|
|
|
ep->syncbuf = NULL;
|
|
ep->nurbs = 0;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* configure a data endpoint
|
|
*/
|
|
static int data_ep_set_params(struct snd_usb_endpoint *ep)
|
|
{
|
|
struct snd_usb_audio *chip = ep->chip;
|
|
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;
|
|
const struct audioformat *fmt = ep->cur_audiofmt;
|
|
int frame_bits = ep->cur_frame_bytes * 8;
|
|
int tx_length_quirk = (has_tx_length_quirk(chip) &&
|
|
usb_pipeout(ep->pipe));
|
|
|
|
usb_audio_dbg(chip, "Setting params for data EP 0x%x, pipe 0x%x\n",
|
|
ep->ep_num, ep->pipe);
|
|
|
|
if (ep->cur_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 += ep->cur_channels << 3;
|
|
}
|
|
|
|
ep->datainterval = fmt->datainterval;
|
|
ep->stride = frame_bits >> 3;
|
|
|
|
switch (ep->cur_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(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 (ep->sync_source && !ep->implicit_fb_sync)
|
|
max_packs_per_urb = min(max_packs_per_urb,
|
|
1U << ep->sync_source->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) || ep->implicit_fb_sync) {
|
|
|
|
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(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 >= ep->cur_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 (ep->sync_source)
|
|
minsize -= minsize >> 3;
|
|
minsize = max(minsize, 1u);
|
|
|
|
/* how many packets will contain an entire ALSA period? */
|
|
max_packs_per_period = DIV_ROUND_UP(ep->cur_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(ep->cur_period_frames,
|
|
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 * ep->cur_buffer_periods);
|
|
}
|
|
|
|
/* 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(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, false);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/*
|
|
* configure a sync endpoint
|
|
*/
|
|
static int sync_ep_set_params(struct snd_usb_endpoint *ep)
|
|
{
|
|
struct snd_usb_audio *chip = ep->chip;
|
|
int i;
|
|
|
|
usb_audio_dbg(chip, "Setting params for sync EP 0x%x, pipe 0x%x\n",
|
|
ep->ep_num, ep->pipe);
|
|
|
|
ep->syncbuf = usb_alloc_coherent(chip->dev, SYNC_URBS * 4,
|
|
GFP_KERNEL, &ep->sync_dma);
|
|
if (!ep->syncbuf)
|
|
return -ENOMEM;
|
|
|
|
ep->nurbs = SYNC_URBS;
|
|
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;
|
|
}
|
|
|
|
return 0;
|
|
|
|
out_of_memory:
|
|
release_urbs(ep, false);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* update the rate of the referred clock; return the actual rate */
|
|
static int update_clock_ref_rate(struct snd_usb_audio *chip,
|
|
struct snd_usb_endpoint *ep)
|
|
{
|
|
struct snd_usb_clock_ref *clock = ep->clock_ref;
|
|
int rate = ep->cur_rate;
|
|
|
|
if (!clock || clock->rate == rate)
|
|
return rate;
|
|
if (clock->rate) {
|
|
if (atomic_read(&clock->locked))
|
|
return clock->rate;
|
|
if (clock->rate != rate) {
|
|
usb_audio_err(chip, "Mismatched sample rate %d vs %d for EP 0x%x\n",
|
|
clock->rate, rate, ep->ep_num);
|
|
return clock->rate;
|
|
}
|
|
}
|
|
clock->rate = rate;
|
|
clock->need_setup = true;
|
|
return rate;
|
|
}
|
|
|
|
/*
|
|
* snd_usb_endpoint_set_params: configure an snd_usb_endpoint
|
|
*
|
|
* It's called either from hw_params callback.
|
|
* 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_audio *chip,
|
|
struct snd_usb_endpoint *ep)
|
|
{
|
|
const struct audioformat *fmt = ep->cur_audiofmt;
|
|
int err = 0;
|
|
|
|
mutex_lock(&chip->mutex);
|
|
if (!ep->need_setup)
|
|
goto unlock;
|
|
|
|
/* release old buffers, if any */
|
|
err = release_urbs(ep, false);
|
|
if (err < 0)
|
|
goto unlock;
|
|
|
|
ep->datainterval = fmt->datainterval;
|
|
ep->maxpacksize = fmt->maxpacksize;
|
|
ep->fill_max = !!(fmt->attributes & UAC_EP_CS_ATTR_FILL_MAX);
|
|
|
|
if (snd_usb_get_speed(chip->dev) == USB_SPEED_FULL) {
|
|
ep->freqn = get_usb_full_speed_rate(ep->cur_rate);
|
|
ep->pps = 1000 >> ep->datainterval;
|
|
} else {
|
|
ep->freqn = get_usb_high_speed_rate(ep->cur_rate);
|
|
ep->pps = 8000 >> ep->datainterval;
|
|
}
|
|
|
|
ep->sample_rem = ep->cur_rate % ep->pps;
|
|
ep->packsize[0] = ep->cur_rate / ep->pps;
|
|
ep->packsize[1] = (ep->cur_rate + (ep->pps - 1)) / ep->pps;
|
|
|
|
/* 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);
|
|
break;
|
|
case SND_USB_ENDPOINT_TYPE_SYNC:
|
|
err = sync_ep_set_params(ep);
|
|
break;
|
|
default:
|
|
err = -EINVAL;
|
|
}
|
|
|
|
usb_audio_dbg(chip, "Set up %d URBS, ret=%d\n", ep->nurbs, err);
|
|
|
|
if (err < 0)
|
|
goto unlock;
|
|
|
|
/* some unit conversions in runtime */
|
|
ep->maxframesize = ep->maxpacksize / ep->cur_frame_bytes;
|
|
ep->curframesize = ep->curpacksize / ep->cur_frame_bytes;
|
|
|
|
err = update_clock_ref_rate(chip, ep);
|
|
if (err >= 0) {
|
|
ep->need_setup = false;
|
|
err = 0;
|
|
}
|
|
|
|
unlock:
|
|
mutex_unlock(&chip->mutex);
|
|
return err;
|
|
}
|
|
|
|
static int init_sample_rate(struct snd_usb_audio *chip,
|
|
struct snd_usb_endpoint *ep)
|
|
{
|
|
struct snd_usb_clock_ref *clock = ep->clock_ref;
|
|
int rate, err;
|
|
|
|
rate = update_clock_ref_rate(chip, ep);
|
|
if (rate < 0)
|
|
return rate;
|
|
if (clock && !clock->need_setup)
|
|
return 0;
|
|
|
|
if (!ep->fixed_rate) {
|
|
err = snd_usb_init_sample_rate(chip, ep->cur_audiofmt, rate);
|
|
if (err < 0) {
|
|
if (clock)
|
|
clock->rate = 0; /* reset rate */
|
|
return err;
|
|
}
|
|
}
|
|
|
|
if (clock)
|
|
clock->need_setup = false;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* snd_usb_endpoint_prepare: Prepare the endpoint
|
|
*
|
|
* This function sets up the EP to be fully usable state.
|
|
* It's called either from prepare callback.
|
|
* The function checks need_setup flag, and performs nothing unless needed,
|
|
* so it's safe to call this multiple times.
|
|
*
|
|
* This returns zero if unchanged, 1 if the configuration has changed,
|
|
* or a negative error code.
|
|
*/
|
|
int snd_usb_endpoint_prepare(struct snd_usb_audio *chip,
|
|
struct snd_usb_endpoint *ep)
|
|
{
|
|
bool iface_first;
|
|
int err = 0;
|
|
|
|
mutex_lock(&chip->mutex);
|
|
if (WARN_ON(!ep->iface_ref))
|
|
goto unlock;
|
|
if (!ep->need_prepare)
|
|
goto unlock;
|
|
|
|
/* If the interface has been already set up, just set EP parameters */
|
|
if (!ep->iface_ref->need_setup) {
|
|
/* sample rate setup of UAC1 is per endpoint, and we need
|
|
* to update at each EP configuration
|
|
*/
|
|
if (ep->cur_audiofmt->protocol == UAC_VERSION_1) {
|
|
err = init_sample_rate(chip, ep);
|
|
if (err < 0)
|
|
goto unlock;
|
|
}
|
|
goto done;
|
|
}
|
|
|
|
/* Need to deselect altsetting at first */
|
|
endpoint_set_interface(chip, ep, false);
|
|
|
|
/* Some UAC1 devices (e.g. Yamaha THR10) need the host interface
|
|
* to be set up before parameter setups
|
|
*/
|
|
iface_first = ep->cur_audiofmt->protocol == UAC_VERSION_1;
|
|
/* Workaround for devices that require the interface setup at first like UAC1 */
|
|
if (chip->quirk_flags & QUIRK_FLAG_SET_IFACE_FIRST)
|
|
iface_first = true;
|
|
if (iface_first) {
|
|
err = endpoint_set_interface(chip, ep, true);
|
|
if (err < 0)
|
|
goto unlock;
|
|
}
|
|
|
|
err = snd_usb_init_pitch(chip, ep->cur_audiofmt);
|
|
if (err < 0)
|
|
goto unlock;
|
|
|
|
err = init_sample_rate(chip, ep);
|
|
if (err < 0)
|
|
goto unlock;
|
|
|
|
err = snd_usb_select_mode_quirk(chip, ep->cur_audiofmt);
|
|
if (err < 0)
|
|
goto unlock;
|
|
|
|
/* for UAC2/3, enable the interface altset here at last */
|
|
if (!iface_first) {
|
|
err = endpoint_set_interface(chip, ep, true);
|
|
if (err < 0)
|
|
goto unlock;
|
|
}
|
|
|
|
ep->iface_ref->need_setup = false;
|
|
|
|
done:
|
|
ep->need_prepare = false;
|
|
err = 1;
|
|
|
|
unlock:
|
|
mutex_unlock(&chip->mutex);
|
|
return err;
|
|
}
|
|
|
|
/* get the current rate set to the given clock by any endpoint */
|
|
int snd_usb_endpoint_get_clock_rate(struct snd_usb_audio *chip, int clock)
|
|
{
|
|
struct snd_usb_clock_ref *ref;
|
|
int rate = 0;
|
|
|
|
if (!clock)
|
|
return 0;
|
|
mutex_lock(&chip->mutex);
|
|
list_for_each_entry(ref, &chip->clock_ref_list, list) {
|
|
if (ref->clock == clock) {
|
|
rate = ref->rate;
|
|
break;
|
|
}
|
|
}
|
|
mutex_unlock(&chip->mutex);
|
|
return rate;
|
|
}
|
|
|
|
/**
|
|
* snd_usb_endpoint_start: start an snd_usb_endpoint
|
|
*
|
|
* @ep: the endpoint to start
|
|
*
|
|
* A call to this function will increment the running 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)
|
|
{
|
|
bool is_playback = usb_pipeout(ep->pipe);
|
|
int err;
|
|
unsigned int i;
|
|
|
|
if (atomic_read(&ep->chip->shutdown))
|
|
return -EBADFD;
|
|
|
|
if (ep->sync_source)
|
|
WRITE_ONCE(ep->sync_source->sync_sink, ep);
|
|
|
|
usb_audio_dbg(ep->chip, "Starting %s EP 0x%x (running %d)\n",
|
|
ep_type_name(ep->type), ep->ep_num,
|
|
atomic_read(&ep->running));
|
|
|
|
/* already running? */
|
|
if (atomic_inc_return(&ep->running) != 1)
|
|
return 0;
|
|
|
|
if (ep->clock_ref)
|
|
atomic_inc(&ep->clock_ref->locked);
|
|
|
|
ep->active_mask = 0;
|
|
ep->unlink_mask = 0;
|
|
ep->phase = 0;
|
|
ep->sample_accum = 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.
|
|
*/
|
|
|
|
if (!ep_state_update(ep, EP_STATE_STOPPED, EP_STATE_RUNNING))
|
|
goto __error;
|
|
|
|
if (snd_usb_endpoint_implicit_feedback_sink(ep) &&
|
|
!(ep->chip->quirk_flags & QUIRK_FLAG_PLAYBACK_FIRST)) {
|
|
usb_audio_dbg(ep->chip, "No URB submission due to implicit fb sync\n");
|
|
i = 0;
|
|
goto fill_rest;
|
|
}
|
|
|
|
for (i = 0; i < ep->nurbs; i++) {
|
|
struct urb *urb = ep->urb[i].urb;
|
|
|
|
if (snd_BUG_ON(!urb))
|
|
goto __error;
|
|
|
|
if (is_playback)
|
|
err = prepare_outbound_urb(ep, urb->context, true);
|
|
else
|
|
err = prepare_inbound_urb(ep, urb->context);
|
|
if (err < 0) {
|
|
/* stop filling at applptr */
|
|
if (err == -EAGAIN)
|
|
break;
|
|
usb_audio_dbg(ep->chip,
|
|
"EP 0x%x: failed to prepare urb: %d\n",
|
|
ep->ep_num, err);
|
|
goto __error;
|
|
}
|
|
|
|
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);
|
|
atomic_inc(&ep->submitted_urbs);
|
|
}
|
|
|
|
if (!i) {
|
|
usb_audio_dbg(ep->chip, "XRUN at starting EP 0x%x\n",
|
|
ep->ep_num);
|
|
goto __error;
|
|
}
|
|
|
|
usb_audio_dbg(ep->chip, "%d URBs submitted for EP 0x%x\n",
|
|
i, ep->ep_num);
|
|
|
|
fill_rest:
|
|
/* put the remaining URBs to ready list */
|
|
if (is_playback) {
|
|
for (; i < ep->nurbs; i++)
|
|
push_back_to_ready_list(ep, ep->urb + i);
|
|
}
|
|
|
|
return 0;
|
|
|
|
__error:
|
|
snd_usb_endpoint_stop(ep, false);
|
|
return -EPIPE;
|
|
}
|
|
|
|
/**
|
|
* snd_usb_endpoint_stop: stop an snd_usb_endpoint
|
|
*
|
|
* @ep: the endpoint to stop (may be NULL)
|
|
* @keep_pending: keep in-flight URBs
|
|
*
|
|
* A call to this function will decrement the running 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, bool keep_pending)
|
|
{
|
|
if (!ep)
|
|
return;
|
|
|
|
usb_audio_dbg(ep->chip, "Stopping %s EP 0x%x (running %d)\n",
|
|
ep_type_name(ep->type), ep->ep_num,
|
|
atomic_read(&ep->running));
|
|
|
|
if (snd_BUG_ON(!atomic_read(&ep->running)))
|
|
return;
|
|
|
|
if (!atomic_dec_return(&ep->running)) {
|
|
if (ep->sync_source)
|
|
WRITE_ONCE(ep->sync_source->sync_sink, NULL);
|
|
stop_urbs(ep, false, keep_pending);
|
|
if (ep->clock_ref)
|
|
atomic_dec(&ep->clock_ref->locked);
|
|
|
|
if (ep->chip->quirk_flags & QUIRK_FLAG_FORCE_IFACE_RESET &&
|
|
usb_pipeout(ep->pipe)) {
|
|
ep->need_prepare = true;
|
|
if (ep->iface_ref)
|
|
ep->iface_ref->need_setup = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* snd_usb_endpoint_release: Tear down an snd_usb_endpoint
|
|
*
|
|
* @ep: the endpoint to release
|
|
*
|
|
* This function does not care for the endpoint's running count but will tear
|
|
* down all the streaming URBs immediately.
|
|
*/
|
|
void snd_usb_endpoint_release(struct snd_usb_endpoint *ep)
|
|
{
|
|
release_urbs(ep, true);
|
|
}
|
|
|
|
/**
|
|
* snd_usb_endpoint_free_all: Free the resources of an snd_usb_endpoint
|
|
* @chip: The chip
|
|
*
|
|
* This free all endpoints and those resources
|
|
*/
|
|
void snd_usb_endpoint_free_all(struct snd_usb_audio *chip)
|
|
{
|
|
struct snd_usb_endpoint *ep, *en;
|
|
struct snd_usb_iface_ref *ip, *in;
|
|
struct snd_usb_clock_ref *cp, *cn;
|
|
|
|
list_for_each_entry_safe(ep, en, &chip->ep_list, list)
|
|
kfree(ep);
|
|
|
|
list_for_each_entry_safe(ip, in, &chip->iface_ref_list, list)
|
|
kfree(ip);
|
|
|
|
list_for_each_entry_safe(cp, cn, &chip->clock_ref_list, list)
|
|
kfree(cp);
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
static 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) &&
|
|
atomic_read(&ep->running)) {
|
|
|
|
/* 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);
|
|
if (ep->next_packet_queued >= ARRAY_SIZE(ep->next_packet)) {
|
|
spin_unlock_irqrestore(&ep->lock, flags);
|
|
usb_audio_err(ep->chip,
|
|
"next package FIFO overflow EP 0x%x\n",
|
|
ep->ep_num);
|
|
notify_xrun(ep);
|
|
return;
|
|
}
|
|
|
|
out_packet = next_packet_fifo_enqueue(ep);
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
spin_unlock_irqrestore(&ep->lock, flags);
|
|
snd_usb_queue_pending_output_urbs(ep, false);
|
|
|
|
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;
|
|
}
|
|
}
|
|
|