[alsa-devel] [PATCH v5 4/4] ASoC: SAMSUNG: Add I2S0 internal dma driver

Seungwhan Youn claude.youn at gmail.com
Tue Jul 19 01:44:18 CEST 2011

Hi Jassi,

On Wed, Jul 13, 2011 at 2:41 PM, Jassi Brar <jassisinghbrar at gmail.com> wrote:
> On Wed, Jul 13, 2011 at 8:38 AM, Seungwhan Youn <claude.youn at gmail.com> wrote:
>> Hi,
>> On Wed, Jul 13, 2011 at 10:25 AM, Sangbeom Kim <sbkim73 at samsung.com> wrote:
>>> I2S in Exynos4 and S5PC110(S5PV210) has a internal dma.
>>> It can be used low power audio mode and 2nd channel transfer.
>>> This patch can support idma.
>>> Signed-off-by: Sangbeom Kim <sbkim73 at samsung.com>
>>> ---
>> In this case, MAX_IDMA_BUFFER is 160k and MAX_IDMA_PERIOD is 128k,
>> buffer is not twice of period. If you set like this, many of general
>> ALSA applications return error on initial buffers.
> I don't think so. Did you see any such problem ?
> In my opnion, ALSA will always use 2 periods of approx. MAX_IDMA_BUFFER/2 bytes

I'm sorry for late reply. Yes, I was wrong. After your reply, I tested
simple speaker-test with applying this patch, and it worked correctly.
I'm sorry for this conflict.

More information about the Alsa-devel mailing list