From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.gmx.net (mail.gmx.net [213.165.64.20]) by ozlabs.org (Postfix) with SMTP id C5160DDE1C for ; Sat, 3 Nov 2007 04:52:25 +1100 (EST) Subject: [PATCH] [ML403-AC97CR] Fix capture/periodic overrun bug. From: Joachim Foerster To: linuxppc-embedded , alsa-devel Content-Type: text/plain Date: Fri, 02 Nov 2007 18:52:19 +0100 Message-Id: <1194025939.29723.22.camel@localhost> Mime-Version: 1.0 Cc: Takashi Iwai , Stephen Neuendorffer , Lorenz Kolb List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi all, this is a bug fix for my ALSA driver I posted in August. Since then I hadn't the time to look at it, but some days ago I took some time and found the reason why there are so many overruns while capturing. Furthermore, this patch removes the one "heavy" printk for capture debugging. From: Joachim Foerster We have to do fairly accurate counting of the minimal periods, instead of being lazy and just setting the number to zero as soon as one period elapses. Signed-off-by: Joachim Foerster --- sound/drivers/ml403-ac97cr.c | 6 ++---- sound/drivers/pcm-indirect2.c | 20 ++------------------ 2 files changed, 4 insertions(+), 22 deletions(-) diff --git a/sound/drivers/ml403-ac97cr.c b/sound/drivers/ml403-ac97cr.c index 2636249..1b16a21 100644 --- a/sound/drivers/ml403-ac97cr.c +++ b/sound/drivers/ml403-ac97cr.c @@ -28,11 +28,9 @@ * accesses to a minimum, because after a variable amount of accesses, the AC97 * controller doesn't raise the register access finished bit anymore ... * - * - Capture support works - basically, but after ~30s (with rates > ~20kHz) - * ALSA stops reading captured samples from the intermediate buffer and - * therefore a overrun happens - ATM I don't know what's wrong. - * * - Playback support seems to be pretty stable - no issues here. + * - Capture support "works" now, too. Overruns don't happen any longer so often. + * But there might still be some ... */ #include diff --git a/sound/drivers/pcm-indirect2.c b/sound/drivers/pcm-indirect2.c index a36215a..ef74a38 100644 --- a/sound/drivers/pcm-indirect2.c +++ b/sound/drivers/pcm-indirect2.c @@ -403,7 +403,7 @@ snd_pcm_indirect2_playback_interrupt(struct snd_pcm_substream *substream, rec->min_multiple); rec->mul_elapsed++; #endif - rec->min_periods = 0; + rec->min_periods = (rec->min_periods % rec->min_multiple); snd_pcm_period_elapsed(substream); } } @@ -568,24 +568,8 @@ snd_pcm_indirect2_capture_interrupt(struct snd_pcm_substream *substream, rec->mul_elapsed_real += (rec->min_periods / rec->min_multiple); rec->mul_elapsed++; - - if (!(rec->mul_elapsed % 4)) { - struct snd_pcm_runtime *runtime = substream->runtime; - unsigned int appl_ptr = - frames_to_bytes(runtime, - (unsigned int)runtime->control-> - appl_ptr) % rec->sw_buffer_size; - int diff = rec->sw_data - appl_ptr; - if (diff < 0) - diff += rec->sw_buffer_size; - snd_printk(KERN_DEBUG - "STAT: mul_elapsed: %d, sw_data: %u, " - "appl_ptr (bytes): %u, diff: %d\n", - rec->mul_elapsed, rec->sw_data, appl_ptr, - diff); - } #endif - rec->min_periods = 0; + rec->min_periods = (rec->min_periods % rec->min_multiple); snd_pcm_period_elapsed(substream); } } -- 1.5.2.5