diff options
| author | Clemens Ladisch <clemens@ladisch.de> | 2010-05-21 09:15:59 +0200 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2010-05-21 16:33:34 +0200 |
| commit | ead4046b2fdfd69acc4272e693afd249ad3eb689 (patch) | |
| tree | 9dbc91adb9f4c654f6b9eaa245422162f12e8e47 /sound/core/pcm_native.c | |
| parent | 7f06a8b26aba1dc03b42272dc0089a800372c575 (diff) | |
ALSA: pcm: fix the fix of the runtime->boundary calculation
Commit 7910b4a1db63fefc3d291853d33c34c5b6352e8e in 2.6.34 changed the
runtime->boundary calculation to make this value a multiple of both the
buffer_size and the period_size, because the latter is assumed by the
runtime->hw_ptr_interrupt calculation.
However, due to the lack of a ioctl that could read the software
parameters before they are set, the kernel requires that alsa-lib
calculates the boundary value, too. The changed algorithm leads to
a different boundary value used by alsa-lib, which makes, e.g., mplayer
fail to play a 44.1 kHz file because the silence_size parameter is now
invalid; bug report:
<https://bugtrack.alsa-project.org/alsa-bug/view.php?id=5015>.
This patch reverts the change to the boundary calculation, and instead
fixes the hw_ptr_interrupt calculation to be period-aligned regardless
of the boundary value.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: <stable@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/core/pcm_native.c')
| -rw-r--r-- | sound/core/pcm_native.c | 39 |
1 files changed, 3 insertions, 36 deletions
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c index 644c2bb17b86..303ac04ff6e4 100644 --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -27,7 +27,6 @@ #include <linux/pm_qos_params.h> #include <linux/uio.h> #include <linux/dma-mapping.h> -#include <linux/math64.h> #include <sound/core.h> #include <sound/control.h> #include <sound/info.h> @@ -370,38 +369,6 @@ static int period_to_usecs(struct snd_pcm_runtime *runtime) return usecs; } -static int calc_boundary(struct snd_pcm_runtime *runtime) -{ - u_int64_t boundary; - - boundary = (u_int64_t)runtime->buffer_size * - (u_int64_t)runtime->period_size; -#if BITS_PER_LONG < 64 - /* try to find lowest common multiple for buffer and period */ - if (boundary > LONG_MAX - runtime->buffer_size) { - u_int32_t remainder = -1; - u_int32_t divident = runtime->buffer_size; - u_int32_t divisor = runtime->period_size; - while (remainder) { - remainder = divident % divisor; - if (remainder) { - divident = divisor; - divisor = remainder; - } - } - boundary = div_u64(boundary, divisor); - if (boundary > LONG_MAX - runtime->buffer_size) - return -ERANGE; - } -#endif - if (boundary == 0) - return -ERANGE; - runtime->boundary = boundary; - while (runtime->boundary * 2 <= LONG_MAX - runtime->buffer_size) - runtime->boundary *= 2; - return 0; -} - static int snd_pcm_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params) { @@ -477,9 +444,9 @@ static int snd_pcm_hw_params(struct snd_pcm_substream *substream, runtime->stop_threshold = runtime->buffer_size; runtime->silence_threshold = 0; runtime->silence_size = 0; - err = calc_boundary(runtime); - if (err < 0) - goto _error; + runtime->boundary = runtime->buffer_size; + while (runtime->boundary * 2 <= LONG_MAX - runtime->buffer_size) + runtime->boundary *= 2; snd_pcm_timer_resolution_change(substream); runtime->status->state = SNDRV_PCM_STATE_SETUP; |