redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

ASoC: sprd: Add reserved DMA memory support 

For Spreadtrum audio platform driver, it need allocate a larger DMA buffer
dynamically to copy audio data between userspace and kernel space, but that
will increase the risk of memory allocation failure especially the system
is under heavy load situation.

To make sure the audio can work in this scenario, we usually reserve one
region of memory to be used as a shared pool of DMA buffers for the
platform component. So add of_reserved_mem_device_init_by_idx() function
to initialize the shared pool of DMA buffers to be used by the platform
component.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
hifive-unleashed-5.2
Baolin Wang 2019-04-12 14:40:17 +08:00 committed by Mark Brown
parent 16ec5dfe03
commit 1587a061ef
No known key found for this signature in database
GPG Key ID: 24D68B725D5487D0
1 changed files with 7 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
sound/soc/sprd/sprd-pcm-dma.c
View File

@ -6,6 +6,7 @@
#include <linux/dma/sprd-dma.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_reserved_mem.h>
#include <linux/platform_device.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
@ -530,8 +531,14 @@ static const struct snd_soc_component_driver sprd_soc_component = {
static int sprd_soc_platform_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
int ret;
ret = of_reserved_mem_device_init_by_idx(&pdev->dev, np, 0);
if (ret)
dev_warn(&pdev->dev,
"no reserved DMA memory for audio platform device\n");
ret = devm_snd_soc_register_component(&pdev->dev, &sprd_soc_component,
NULL, 0);
if (ret)