mirror of
https://github.com/torvalds/linux.git
synced 2024-12-02 00:51:44 +00:00
0146878cf2
As PCM ack callback may handle the XRUN situation gracefully now,
change the indirect PCM helpers to give a proper error (-EPIPE).
Also, change the pointer callback helpers to deal with the XRUN error
properly, too.
This requires the PCM core change by the commit 8c721c53dd
("ALSA: usb-audio: Fix recursive locking at XRUN during syncing").
Link: https://lore.kernel.org/r/20230323065237.5062-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
181 lines
5.2 KiB
C
181 lines
5.2 KiB
C
/* SPDX-License-Identifier: GPL-2.0-or-later */
|
|
/*
|
|
* Helper functions for indirect PCM data transfer
|
|
*
|
|
* Copyright (c) by Takashi Iwai <tiwai@suse.de>
|
|
* Jaroslav Kysela <perex@perex.cz>
|
|
*/
|
|
|
|
#ifndef __SOUND_PCM_INDIRECT_H
|
|
#define __SOUND_PCM_INDIRECT_H
|
|
|
|
#include <sound/pcm.h>
|
|
|
|
struct snd_pcm_indirect {
|
|
unsigned int hw_buffer_size; /* Byte size of hardware buffer */
|
|
unsigned int hw_queue_size; /* Max queue size of hw buffer (0 = buffer size) */
|
|
unsigned int hw_data; /* Offset to next dst (or src) in hw ring buffer */
|
|
unsigned int hw_io; /* Ring buffer hw pointer */
|
|
int hw_ready; /* Bytes ready for play (or captured) in hw ring buffer */
|
|
unsigned int sw_buffer_size; /* Byte size of software buffer */
|
|
unsigned int sw_data; /* Offset to next dst (or src) in sw ring buffer */
|
|
unsigned int sw_io; /* Current software pointer in bytes */
|
|
int sw_ready; /* Bytes ready to be transferred to/from hw */
|
|
snd_pcm_uframes_t appl_ptr; /* Last seen appl_ptr */
|
|
};
|
|
|
|
typedef void (*snd_pcm_indirect_copy_t)(struct snd_pcm_substream *substream,
|
|
struct snd_pcm_indirect *rec, size_t bytes);
|
|
|
|
/*
|
|
* helper function for playback ack callback
|
|
*/
|
|
static inline int
|
|
snd_pcm_indirect_playback_transfer(struct snd_pcm_substream *substream,
|
|
struct snd_pcm_indirect *rec,
|
|
snd_pcm_indirect_copy_t copy)
|
|
{
|
|
struct snd_pcm_runtime *runtime = substream->runtime;
|
|
snd_pcm_uframes_t appl_ptr = runtime->control->appl_ptr;
|
|
snd_pcm_sframes_t diff = appl_ptr - rec->appl_ptr;
|
|
int qsize;
|
|
|
|
if (diff) {
|
|
if (diff < -(snd_pcm_sframes_t) (runtime->boundary / 2))
|
|
diff += runtime->boundary;
|
|
if (diff < 0)
|
|
return -EPIPE;
|
|
rec->sw_ready += (int)frames_to_bytes(runtime, diff);
|
|
rec->appl_ptr = appl_ptr;
|
|
}
|
|
qsize = rec->hw_queue_size ? rec->hw_queue_size : rec->hw_buffer_size;
|
|
while (rec->hw_ready < qsize && rec->sw_ready > 0) {
|
|
unsigned int hw_to_end = rec->hw_buffer_size - rec->hw_data;
|
|
unsigned int sw_to_end = rec->sw_buffer_size - rec->sw_data;
|
|
unsigned int bytes = qsize - rec->hw_ready;
|
|
if (rec->sw_ready < (int)bytes)
|
|
bytes = rec->sw_ready;
|
|
if (hw_to_end < bytes)
|
|
bytes = hw_to_end;
|
|
if (sw_to_end < bytes)
|
|
bytes = sw_to_end;
|
|
if (! bytes)
|
|
break;
|
|
copy(substream, rec, bytes);
|
|
rec->hw_data += bytes;
|
|
if (rec->hw_data == rec->hw_buffer_size)
|
|
rec->hw_data = 0;
|
|
rec->sw_data += bytes;
|
|
if (rec->sw_data == rec->sw_buffer_size)
|
|
rec->sw_data = 0;
|
|
rec->hw_ready += bytes;
|
|
rec->sw_ready -= bytes;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* helper function for playback pointer callback
|
|
* ptr = current byte pointer
|
|
*/
|
|
static inline snd_pcm_uframes_t
|
|
snd_pcm_indirect_playback_pointer(struct snd_pcm_substream *substream,
|
|
struct snd_pcm_indirect *rec, unsigned int ptr)
|
|
{
|
|
int bytes = ptr - rec->hw_io;
|
|
int err;
|
|
|
|
if (bytes < 0)
|
|
bytes += rec->hw_buffer_size;
|
|
rec->hw_io = ptr;
|
|
rec->hw_ready -= bytes;
|
|
rec->sw_io += bytes;
|
|
if (rec->sw_io >= rec->sw_buffer_size)
|
|
rec->sw_io -= rec->sw_buffer_size;
|
|
if (substream->ops->ack) {
|
|
err = substream->ops->ack(substream);
|
|
if (err == -EPIPE)
|
|
return SNDRV_PCM_POS_XRUN;
|
|
}
|
|
return bytes_to_frames(substream->runtime, rec->sw_io);
|
|
}
|
|
|
|
|
|
/*
|
|
* helper function for capture ack callback
|
|
*/
|
|
static inline int
|
|
snd_pcm_indirect_capture_transfer(struct snd_pcm_substream *substream,
|
|
struct snd_pcm_indirect *rec,
|
|
snd_pcm_indirect_copy_t copy)
|
|
{
|
|
struct snd_pcm_runtime *runtime = substream->runtime;
|
|
snd_pcm_uframes_t appl_ptr = runtime->control->appl_ptr;
|
|
snd_pcm_sframes_t diff = appl_ptr - rec->appl_ptr;
|
|
|
|
if (diff) {
|
|
if (diff < -(snd_pcm_sframes_t) (runtime->boundary / 2))
|
|
diff += runtime->boundary;
|
|
if (diff < 0)
|
|
return -EPIPE;
|
|
rec->sw_ready -= frames_to_bytes(runtime, diff);
|
|
rec->appl_ptr = appl_ptr;
|
|
}
|
|
while (rec->hw_ready > 0 &&
|
|
rec->sw_ready < (int)rec->sw_buffer_size) {
|
|
size_t hw_to_end = rec->hw_buffer_size - rec->hw_data;
|
|
size_t sw_to_end = rec->sw_buffer_size - rec->sw_data;
|
|
size_t bytes = rec->sw_buffer_size - rec->sw_ready;
|
|
if (rec->hw_ready < (int)bytes)
|
|
bytes = rec->hw_ready;
|
|
if (hw_to_end < bytes)
|
|
bytes = hw_to_end;
|
|
if (sw_to_end < bytes)
|
|
bytes = sw_to_end;
|
|
if (! bytes)
|
|
break;
|
|
copy(substream, rec, bytes);
|
|
rec->hw_data += bytes;
|
|
if ((int)rec->hw_data == rec->hw_buffer_size)
|
|
rec->hw_data = 0;
|
|
rec->sw_data += bytes;
|
|
if (rec->sw_data == rec->sw_buffer_size)
|
|
rec->sw_data = 0;
|
|
rec->hw_ready -= bytes;
|
|
rec->sw_ready += bytes;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* helper function for capture pointer callback,
|
|
* ptr = current byte pointer
|
|
*/
|
|
static inline snd_pcm_uframes_t
|
|
snd_pcm_indirect_capture_pointer(struct snd_pcm_substream *substream,
|
|
struct snd_pcm_indirect *rec, unsigned int ptr)
|
|
{
|
|
int qsize;
|
|
int bytes = ptr - rec->hw_io;
|
|
int err;
|
|
|
|
if (bytes < 0)
|
|
bytes += rec->hw_buffer_size;
|
|
rec->hw_io = ptr;
|
|
rec->hw_ready += bytes;
|
|
qsize = rec->hw_queue_size ? rec->hw_queue_size : rec->hw_buffer_size;
|
|
if (rec->hw_ready > qsize)
|
|
return SNDRV_PCM_POS_XRUN;
|
|
rec->sw_io += bytes;
|
|
if (rec->sw_io >= rec->sw_buffer_size)
|
|
rec->sw_io -= rec->sw_buffer_size;
|
|
if (substream->ops->ack) {
|
|
err = substream->ops->ack(substream);
|
|
if (err == -EPIPE)
|
|
return SNDRV_PCM_POS_XRUN;
|
|
}
|
|
return bytes_to_frames(substream->runtime, rec->sw_io);
|
|
}
|
|
|
|
#endif /* __SOUND_PCM_INDIRECT_H */
|