On 03/03/2015 02:22 PM, Jarkko Nikula wrote:
On Tue, Mar 03, 2015 at 01:41:21PM +0200, Peter Ujfalusi wrote:
On 03/03/2015 01:28 PM, Jyri Sarha wrote:
sDMA support only transfer elements with 1, 2, and 4 byte physical size. Initialize the pcm driver accordingly.
Acked-by: Peter Ujfalusi peter.ujfalusi@ti.com
Signed-off-by: Jyri Sarha jsarha@ti.com
sound/soc/omap/omap-pcm.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-)
diff --git a/sound/soc/omap/omap-pcm.c b/sound/soc/omap/omap-pcm.c index f4b05bc..e49ee23 100644 --- a/sound/soc/omap/omap-pcm.c +++ b/sound/soc/omap/omap-pcm.c @@ -39,7 +39,7 @@ #define pcm_omap1510() 0 #endif
-static const struct snd_pcm_hardware omap_pcm_hardware = { +static struct snd_pcm_hardware omap_pcm_hardware = { .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID | SNDRV_PCM_INFO_INTERLEAVED | @@ -53,6 +53,24 @@ static const struct snd_pcm_hardware omap_pcm_hardware = { .buffer_bytes_max = 128 * 1024, };
+/* sDMA supports only 1, 2, and 4 byte transfer elements. */ +static void omap_pcm_limit_supported_formats(void) +{
- int i;
- for (i = 0; i < SNDRV_PCM_FORMAT_LAST; i++) {
switch (snd_pcm_format_physical_width(i)) {case 8:case 16:case 32:omap_pcm_hardware.formats |= (1LL << i);break;default:break;}- }
+}
I wonder why these are set in a loop instead of setting formats statically
omap-pcm as such can work with any formats which has 1, 2 or 4 bytes layout in memory (and not only S16_LE, S32_LE). sDMA can not handle 3byte words so we can not handle those with omap-pcm. In contrast eDMA for example can handle 1, 2, 3 and 4 w/o issue.
and why this is needed after commit 60e21d287344 ("ASoC: omap: Don't set unused struct snd_pcm_hardware fields")?
Hrm, interesting. We also have: 2d38df128321 (ASoC: generic-dmaengine-pcm: Prepare formats mask for valid physical sample sizes)
Which does the same thing for the generic dmaengine pcm users.
Actually the information from the omap_pcm_hardware is copied to runtime.hw via snd_soc_set_runtime_hwparams() call, so it is not ignored.
We need this masking to be done here since the omap-pcm is still mostly custom code and do not plug easily to the generic code (ie, not at all).