From ed3da3d9a0ef13c6fe1414ec73c9c1be12747b62 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 3 Mar 2009 17:00:15 +0100 Subject: ALSA: Rewrite hw_ptr updaters Clean up and improve snd_pcm_update_hw_ptr*() functions. snd_pcm_update_hw_ptr() tries to detect the unexpected hwptr jumps more strictly to avoid the position mess-up, which often results in the bad quality I/O with pulseaudio. The hw-ptr skip error messages are printed when xrun proc is set to non-zero. Signed-off-by: Takashi Iwai --- sound/core/pcm_lib.c | 128 +++++++++++++++++++++++++++++++++------------------ 1 file changed, 83 insertions(+), 45 deletions(-) (limited to 'sound/core/pcm_lib.c') diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 921691080f3..86ac9ae9460 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -125,19 +125,27 @@ void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_ufram } } +#ifdef CONFIG_SND_PCM_XRUN_DEBUG +#define xrun_debug(substream) ((substream)->pstr->xrun_debug) +#else +#define xrun_debug(substream) 0 +#endif + +#define dump_stack_on_xrun(substream) do { \ + if (xrun_debug(substream) > 1) \ + dump_stack(); \ + } while (0) + static void xrun(struct snd_pcm_substream *substream) { snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN); -#ifdef CONFIG_SND_PCM_XRUN_DEBUG - if (substream->pstr->xrun_debug) { + if (xrun_debug(substream)) { snd_printd(KERN_DEBUG "XRUN: pcmC%dD%d%c\n", substream->pcm->card->number, substream->pcm->device, substream->stream ? 'c' : 'p'); - if (substream->pstr->xrun_debug > 1) - dump_stack(); + dump_stack_on_xrun(substream); } -#endif } static inline snd_pcm_uframes_t snd_pcm_update_hw_ptr_pos(struct snd_pcm_substream *substream, @@ -182,11 +190,21 @@ static inline int snd_pcm_update_hw_ptr_post(struct snd_pcm_substream *substream return 0; } +#define hw_ptr_error(substream, fmt, args...) \ + do { \ + if (xrun_debug(substream)) { \ + if (printk_ratelimit()) { \ + snd_printd("hda_codec: " fmt, ##args); \ + } \ + dump_stack_on_xrun(substream); \ + } \ + } while (0) + static inline int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; snd_pcm_uframes_t pos; - snd_pcm_uframes_t new_hw_ptr, hw_ptr_interrupt; + snd_pcm_uframes_t new_hw_ptr, hw_ptr_interrupt, hw_base; snd_pcm_sframes_t delta; pos = snd_pcm_update_hw_ptr_pos(substream, runtime); @@ -194,36 +212,47 @@ static inline int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *subs xrun(substream); return -EPIPE; } - if (runtime->period_size == runtime->buffer_size) - goto __next_buf; - new_hw_ptr = runtime->hw_ptr_base + pos; + hw_base = runtime->hw_ptr_base; + new_hw_ptr = hw_base + pos; hw_ptr_interrupt = runtime->hw_ptr_interrupt + runtime->period_size; - - delta = hw_ptr_interrupt - new_hw_ptr; - if (delta > 0) { - if ((snd_pcm_uframes_t)delta < runtime->buffer_size / 2) { -#ifdef CONFIG_SND_PCM_XRUN_DEBUG - if (runtime->periods > 1 && substream->pstr->xrun_debug) { - snd_printd(KERN_ERR "Unexpected hw_pointer value [1] (stream = %i, delta: -%ld, max jitter = %ld): wrong interrupt acknowledge?\n", substream->stream, (long) delta, runtime->buffer_size / 2); - if (substream->pstr->xrun_debug > 1) - dump_stack(); - } -#endif - return 0; + delta = new_hw_ptr - hw_ptr_interrupt; + if (hw_ptr_interrupt == runtime->boundary) + hw_ptr_interrupt = 0; + if (delta < 0) { + delta += runtime->buffer_size; + if (delta < 0) { + hw_ptr_error(substream, + "Unexpected hw_pointer value " + "(stream=%i, pos=%ld, intr_ptr=%ld)\n", + substream->stream, (long)pos, + (long)hw_ptr_interrupt); + /* rebase to interrupt position */ + hw_base = new_hw_ptr = hw_ptr_interrupt; + delta = 0; + } else { + hw_base += runtime->buffer_size; + if (hw_base == runtime->boundary) + hw_base = 0; + new_hw_ptr = hw_base + pos; } - __next_buf: - runtime->hw_ptr_base += runtime->buffer_size; - if (runtime->hw_ptr_base == runtime->boundary) - runtime->hw_ptr_base = 0; - new_hw_ptr = runtime->hw_ptr_base + pos; } - + if (delta > runtime->period_size) { + hw_ptr_error(substream, + "Lost interrupts? " + "(stream=%i, delta=%ld, intr_ptr=%ld)\n", + substream->stream, (long)delta, + (long)hw_ptr_interrupt); + /* rebase hw_ptr_interrupt */ + hw_ptr_interrupt = + new_hw_ptr - new_hw_ptr % runtime->period_size; + } if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK && runtime->silence_size > 0) snd_pcm_playback_silence(substream, new_hw_ptr); + runtime->hw_ptr_base = hw_base; runtime->status->hw_ptr = new_hw_ptr; - runtime->hw_ptr_interrupt = new_hw_ptr - new_hw_ptr % runtime->period_size; + runtime->hw_ptr_interrupt = hw_ptr_interrupt; return snd_pcm_update_hw_ptr_post(substream, runtime); } @@ -233,7 +262,7 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; snd_pcm_uframes_t pos; - snd_pcm_uframes_t old_hw_ptr, new_hw_ptr; + snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base; snd_pcm_sframes_t delta; old_hw_ptr = runtime->status->hw_ptr; @@ -242,29 +271,38 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream) xrun(substream); return -EPIPE; } - new_hw_ptr = runtime->hw_ptr_base + pos; - - delta = old_hw_ptr - new_hw_ptr; - if (delta > 0) { - if ((snd_pcm_uframes_t)delta < runtime->buffer_size / 2) { -#ifdef CONFIG_SND_PCM_XRUN_DEBUG - if (runtime->periods > 2 && substream->pstr->xrun_debug) { - snd_printd(KERN_ERR "Unexpected hw_pointer value [2] (stream = %i, delta: -%ld, max jitter = %ld): wrong interrupt acknowledge?\n", substream->stream, (long) delta, runtime->buffer_size / 2); - if (substream->pstr->xrun_debug > 1) - dump_stack(); - } -#endif + hw_base = runtime->hw_ptr_base; + new_hw_ptr = hw_base + pos; + + delta = new_hw_ptr - old_hw_ptr; + if (delta < 0) { + delta += runtime->buffer_size; + if (delta < 0) { + hw_ptr_error(substream, + "Unexpected hw_pointer value [2] " + "(stream=%i, pos=%ld, old_ptr=%ld)\n", + substream->stream, (long)pos, + (long)old_hw_ptr); return 0; } - runtime->hw_ptr_base += runtime->buffer_size; - if (runtime->hw_ptr_base == runtime->boundary) - runtime->hw_ptr_base = 0; - new_hw_ptr = runtime->hw_ptr_base + pos; + hw_base += runtime->buffer_size; + if (hw_base == runtime->boundary) + hw_base = 0; + new_hw_ptr = hw_base + pos; + } + if (delta > runtime->period_size && runtime->periods > 1) { + hw_ptr_error(substream, + "hw_ptr skipping! " + "(pos=%ld, delta=%ld, period=%ld)\n", + (long)pos, (long)delta, + (long)runtime->period_size); + return 0; } if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK && runtime->silence_size > 0) snd_pcm_playback_silence(substream, new_hw_ptr); + runtime->hw_ptr_base = hw_base; runtime->status->hw_ptr = new_hw_ptr; return snd_pcm_update_hw_ptr_post(substream, runtime); -- cgit v1.2.3-18-g5258 From cad377acf3d6af6279622048e96680e79e352183 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 19 Mar 2009 09:55:15 +0100 Subject: ALSA: pcm - Fix a typo in error messages Fix a typo in error messages; forgotten after a copy&paste error. Signed-off-by: Takashi Iwai --- sound/core/pcm_lib.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'sound/core/pcm_lib.c') diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 86ac9ae9460..2ff25ed4d83 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -194,7 +194,7 @@ static inline int snd_pcm_update_hw_ptr_post(struct snd_pcm_substream *substream do { \ if (xrun_debug(substream)) { \ if (printk_ratelimit()) { \ - snd_printd("hda_codec: " fmt, ##args); \ + snd_printd("PCM: " fmt, ##args); \ } \ dump_stack_on_xrun(substream); \ } \ -- cgit v1.2.3-18-g5258 From 98204646f2b15d368701265e4194b773a6f94600 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 19 Mar 2009 09:59:21 +0100 Subject: ALSA: pcm - avoid unnecessary inline Remove unnecessary explicit inlininig of internal functions. Let compiler optimize. Signed-off-by: Takashi Iwai --- sound/core/pcm_lib.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'sound/core/pcm_lib.c') diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 2ff25ed4d83..302654769fa 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -148,8 +148,9 @@ static void xrun(struct snd_pcm_substream *substream) } } -static inline snd_pcm_uframes_t snd_pcm_update_hw_ptr_pos(struct snd_pcm_substream *substream, - struct snd_pcm_runtime *runtime) +static snd_pcm_uframes_t +snd_pcm_update_hw_ptr_pos(struct snd_pcm_substream *substream, + struct snd_pcm_runtime *runtime) { snd_pcm_uframes_t pos; @@ -167,8 +168,8 @@ static inline snd_pcm_uframes_t snd_pcm_update_hw_ptr_pos(struct snd_pcm_substre return pos; } -static inline int snd_pcm_update_hw_ptr_post(struct snd_pcm_substream *substream, - struct snd_pcm_runtime *runtime) +static int snd_pcm_update_hw_ptr_post(struct snd_pcm_substream *substream, + struct snd_pcm_runtime *runtime) { snd_pcm_uframes_t avail; @@ -200,7 +201,7 @@ static inline int snd_pcm_update_hw_ptr_post(struct snd_pcm_substream *substream } \ } while (0) -static inline int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) +static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; snd_pcm_uframes_t pos; -- cgit v1.2.3-18-g5258 From 5f513e1197f27e9a0bcfec0feaac59f976f4a37e Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 19 Mar 2009 10:01:47 +0100 Subject: ALSA: pcm - Reset invalid position even without debug option Always reset the invalind hw_ptr position returned by the pointer callback. The behavior should be consitent independently from the debug option. Also, add the printk_ratelimit() check to avoid flooding debug prints. Signed-off-by: Takashi Iwai --- sound/core/pcm_lib.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'sound/core/pcm_lib.c') diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 302654769fa..92ed6d81922 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -159,11 +159,15 @@ snd_pcm_update_hw_ptr_pos(struct snd_pcm_substream *substream, pos = substream->ops->pointer(substream); if (pos == SNDRV_PCM_POS_XRUN) return pos; /* XRUN */ -#ifdef CONFIG_SND_DEBUG if (pos >= runtime->buffer_size) { - snd_printk(KERN_ERR "BUG: stream = %i, pos = 0x%lx, buffer size = 0x%lx, period size = 0x%lx\n", substream->stream, pos, runtime->buffer_size, runtime->period_size); + if (printk_ratelimit()) { + snd_printd(KERN_ERR "BUG: stream = %i, pos = 0x%lx, " + "buffer size = 0x%lx, period size = 0x%lx\n", + substream->stream, pos, runtime->buffer_size, + runtime->period_size); + } + pos = 0; } -#endif pos -= pos % runtime->min_align; return pos; } -- cgit v1.2.3-18-g5258 From ded652f7024bc2d7b6118b561a44187af30841b0 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 19 Mar 2009 10:08:49 +0100 Subject: ALSA: pcm - Fix delta calculation at boundary overlap When the hw_ptr_interrupt reaches the boundary, it must check whether the hw_base was already lapped and corret the delta value appropriately. Also, rebasing the hw_ptr needs a correction because buffer_size isn't always aligned to period_size. Signed-off-by: Takashi Iwai --- sound/core/pcm_lib.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'sound/core/pcm_lib.c') diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 92ed6d81922..063c675177a 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -221,8 +221,11 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) new_hw_ptr = hw_base + pos; hw_ptr_interrupt = runtime->hw_ptr_interrupt + runtime->period_size; delta = new_hw_ptr - hw_ptr_interrupt; - if (hw_ptr_interrupt == runtime->boundary) - hw_ptr_interrupt = 0; + if (hw_ptr_interrupt >= runtime->boundary) { + hw_ptr_interrupt %= runtime->boundary; + if (!hw_base) /* hw_base was already lapped; recalc delta */ + delta = new_hw_ptr - hw_ptr_interrupt; + } if (delta < 0) { delta += runtime->buffer_size; if (delta < 0) { @@ -233,6 +236,8 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) (long)hw_ptr_interrupt); /* rebase to interrupt position */ hw_base = new_hw_ptr = hw_ptr_interrupt; + /* align hw_base to buffer_size */ + hw_base -= hw_base % runtime->buffer_size; delta = 0; } else { hw_base += runtime->buffer_size; -- cgit v1.2.3-18-g5258 From 8b22d943c34b616eefbd6d2f8f197a53b1f29fd0 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Fri, 20 Mar 2009 16:26:15 +0100 Subject: ALSA: pcm - Safer boundary checks Make the boundary checks a bit safer. These caese are rare or theoretically won't happen, but nothing bad to keep the checks safer... Signed-off-by: Takashi Iwai --- sound/core/pcm_lib.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'sound/core/pcm_lib.c') diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 063c675177a..fbb2e391591 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -222,8 +222,9 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) hw_ptr_interrupt = runtime->hw_ptr_interrupt + runtime->period_size; delta = new_hw_ptr - hw_ptr_interrupt; if (hw_ptr_interrupt >= runtime->boundary) { - hw_ptr_interrupt %= runtime->boundary; - if (!hw_base) /* hw_base was already lapped; recalc delta */ + hw_ptr_interrupt -= runtime->boundary; + if (hw_base < runtime->boundary / 2) + /* hw_base was already lapped; recalc delta */ delta = new_hw_ptr - hw_ptr_interrupt; } if (delta < 0) { @@ -241,7 +242,7 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) delta = 0; } else { hw_base += runtime->buffer_size; - if (hw_base == runtime->boundary) + if (hw_base >= runtime->boundary) hw_base = 0; new_hw_ptr = hw_base + pos; } @@ -296,7 +297,7 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream) return 0; } hw_base += runtime->buffer_size; - if (hw_base == runtime->boundary) + if (hw_base >= runtime->boundary) hw_base = 0; new_hw_ptr = hw_base + pos; } -- cgit v1.2.3-18-g5258 From bbf6ad1399e9516b0a95de3ad58ffbaed670e4cc Mon Sep 17 00:00:00 2001 From: Jaroslav Kysela Date: Fri, 10 Apr 2009 12:28:58 +0200 Subject: [ALSA] pcm-midlevel: Add more strict buffer position checks based on jiffies Some drivers like Intel8x0 or Intel HDA are broken for some hardware variants. This patch adds more strict buffer position checks based on jiffies when internal hw_ptr is updated. Enable xrun_debug to see mangling of wrong positions. As a side effect, the hw_ptr interrupt update routine might do slightly better job when many interrupts are lost. Signed-off-by: Jaroslav Kysela --- sound/core/pcm_lib.c | 47 +++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 39 insertions(+), 8 deletions(-) (limited to 'sound/core/pcm_lib.c') diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index fbb2e391591..63d088f2265 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -209,9 +209,11 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; snd_pcm_uframes_t pos; - snd_pcm_uframes_t new_hw_ptr, hw_ptr_interrupt, hw_base; - snd_pcm_sframes_t delta; + snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_ptr_interrupt, hw_base; + snd_pcm_sframes_t hdelta, delta; + unsigned long jdelta; + old_hw_ptr = runtime->status->hw_ptr; pos = snd_pcm_update_hw_ptr_pos(substream, runtime); if (pos == SNDRV_PCM_POS_XRUN) { xrun(substream); @@ -247,7 +249,30 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) new_hw_ptr = hw_base + pos; } } - if (delta > runtime->period_size) { + hdelta = new_hw_ptr - old_hw_ptr; + jdelta = jiffies - runtime->hw_ptr_jiffies; + if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) { + delta = jdelta / + (((runtime->period_size * HZ) / runtime->rate) + + HZ/100); + hw_ptr_error(substream, + "hw_ptr skipping! [Q] " + "(pos=%ld, delta=%ld, period=%ld, " + "jdelta=%lu/%lu/%lu)\n", + (long)pos, (long)hdelta, + (long)runtime->period_size, jdelta, + ((hdelta * HZ) / runtime->rate), delta); + hw_ptr_interrupt = runtime->hw_ptr_interrupt + + runtime->period_size * delta; + if (hw_ptr_interrupt >= runtime->boundary) + hw_ptr_interrupt -= runtime->boundary; + /* rebase to interrupt position */ + hw_base = new_hw_ptr = hw_ptr_interrupt; + /* align hw_base to buffer_size */ + hw_base -= hw_base % runtime->buffer_size; + delta = 0; + } + if (delta > runtime->period_size + runtime->period_size / 2) { hw_ptr_error(substream, "Lost interrupts? " "(stream=%i, delta=%ld, intr_ptr=%ld)\n", @@ -263,6 +288,7 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) runtime->hw_ptr_base = hw_base; runtime->status->hw_ptr = new_hw_ptr; + runtime->hw_ptr_jiffies = jiffies; runtime->hw_ptr_interrupt = hw_ptr_interrupt; return snd_pcm_update_hw_ptr_post(substream, runtime); @@ -275,6 +301,7 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream) snd_pcm_uframes_t pos; snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base; snd_pcm_sframes_t delta; + unsigned long jdelta; old_hw_ptr = runtime->status->hw_ptr; pos = snd_pcm_update_hw_ptr_pos(substream, runtime); @@ -286,14 +313,15 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream) new_hw_ptr = hw_base + pos; delta = new_hw_ptr - old_hw_ptr; + jdelta = jiffies - runtime->hw_ptr_jiffies; if (delta < 0) { delta += runtime->buffer_size; if (delta < 0) { hw_ptr_error(substream, "Unexpected hw_pointer value [2] " - "(stream=%i, pos=%ld, old_ptr=%ld)\n", + "(stream=%i, pos=%ld, old_ptr=%ld, jdelta=%li)\n", substream->stream, (long)pos, - (long)old_hw_ptr); + (long)old_hw_ptr, jdelta); return 0; } hw_base += runtime->buffer_size; @@ -301,12 +329,13 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream) hw_base = 0; new_hw_ptr = hw_base + pos; } - if (delta > runtime->period_size && runtime->periods > 1) { + if (((delta * HZ) / runtime->rate) > jdelta + HZ/100) { hw_ptr_error(substream, "hw_ptr skipping! " - "(pos=%ld, delta=%ld, period=%ld)\n", + "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu)\n", (long)pos, (long)delta, - (long)runtime->period_size); + (long)runtime->period_size, jdelta, + ((delta * HZ) / runtime->rate)); return 0; } if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK && @@ -315,6 +344,7 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream) runtime->hw_ptr_base = hw_base; runtime->status->hw_ptr = new_hw_ptr; + runtime->hw_ptr_jiffies = jiffies; return snd_pcm_update_hw_ptr_post(substream, runtime); } @@ -1441,6 +1471,7 @@ static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream, runtime->status->hw_ptr %= runtime->buffer_size; else runtime->status->hw_ptr = 0; + runtime->hw_ptr_jiffies = jiffies; snd_pcm_stream_unlock_irqrestore(substream, flags); return 0; } -- cgit v1.2.3-18-g5258 From 3e5b50165fd0be080044586f43fcdd460ed27610 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 28 Apr 2009 12:07:08 +0200 Subject: ALSA: pcm core - Avoid jiffies check for devices with BATCH flag The hardware devices with SNDRV_PCM_INFO_BATCH flag can't give the precise current position. And such hardwares have often big FIFO in addition to the ring buffer, and it screws up the jiffies check in pcm_lib.c. This patch adds a simple check of info flag so that the driver skips the jiffies check in snd_pcm_period_elapsed() when BATCH flag is set. Signed-off-by: Takashi Iwai --- sound/core/pcm_lib.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'sound/core/pcm_lib.c') diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index 63d088f2265..a2a792c18c4 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -249,6 +249,12 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) new_hw_ptr = hw_base + pos; } } + /* Skip the jiffies check for hardwares with BATCH flag. + * Such hardware usually just increases the position at each IRQ, + * thus it can't give any strange position. + */ + if (runtime->hw.info & SNDRV_PCM_INFO_BATCH) + goto no_jiffies_check; hdelta = new_hw_ptr - old_hw_ptr; jdelta = jiffies - runtime->hw_ptr_jiffies; if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) { @@ -272,6 +278,7 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) hw_base -= hw_base % runtime->buffer_size; delta = 0; } + no_jiffies_check: if (delta > runtime->period_size + runtime->period_size / 2) { hw_ptr_error(substream, "Lost interrupts? " -- cgit v1.2.3-18-g5258