Lubancat2/kernel
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

FROMGIT: ASoC: dmaengine: Introduce module option prealloc_buffer_size_kbytes

Browse Source 
Currently, The fixed 512KB prealloc buffer size is too larger for
tiny memory kernel (such as 16MB memory). This patch adds the module
option "prealloc_buffer_size_kbytes" to specify prealloc buffer size.

It's suitable for cards which use the generic dmaengine pcm driver
with no config.

Change-Id: I76cc278f523d41083ba30b36d801d2839682d158
Signed-off-by: Sugar Zhang <sugar.zhang@rock-chips.com>
Link: https://lore.kernel.org/r/1632394246-59341-1-git-send-email-sugar.zhang@rock-chips.com
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit b0e3b0a7078d71455747025e7deee766d4d43432
 git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-5.16)
This commit is contained in:
Sugar Zhang
2021-09-23 18:50:46 +08:00
committed by Tao Huang
parent 0c5249aab1
commit ba2cfd68f4
2 changed files with 14 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
Documentation/sound/alsa-configuration.rst
View File

@ -100,6 +100,15 @@ amidi_map
MIDI device number maps assigned to the 2st OSS device; MIDI device number maps assigned to the 2st OSS device;
Default: 1 Default: 1
Module snd-soc-core
-------------------
The soc core module. It is used by all ALSA card drivers.
It takes the following options which have global effects.
prealloc_buffer_size_kbytes
Specify prealloc buffer size in kbytes (default: 512).
Common parameters for top sound card modules Common parameters for top sound card modules
-------------------------------------------- --------------------------------------------

6
sound/soc/soc-generic-dmaengine-pcm.c
View File

@ -15,6 +15,10 @@
#include <sound/dmaengine_pcm.h> #include <sound/dmaengine_pcm.h>
static unsigned int prealloc_buffer_size_kbytes = 512;
module_param(prealloc_buffer_size_kbytes, uint, 0444);
MODULE_PARM_DESC(prealloc_buffer_size_kbytes, "Preallocate DMA buffer size (KB).");
/* /*
* The platforms dmaengine driver does not support reporting the amount of * The platforms dmaengine driver does not support reporting the amount of
* bytes that are still left to transfer. * bytes that are still left to transfer.
@ -276,7 +280,7 @@ static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
prealloc_buffer_size = config->prealloc_buffer_size; prealloc_buffer_size = config->prealloc_buffer_size;
max_buffer_size = config->pcm_hardware->buffer_bytes_max; max_buffer_size = config->pcm_hardware->buffer_bytes_max;
} else { } else {
prealloc_buffer_size = 512 * 1024; prealloc_buffer_size = prealloc_buffer_size_kbytes * 1024;
max_buffer_size = SIZE_MAX; max_buffer_size = SIZE_MAX;
} }