[PATCH 16/23] intel_sst: MRST can only do mono recording

Alan Cox
2011-05-03T17:54:21Z

From: Wu Fengguang <wfg@linux.intel.com>

Fix bug

$ arecord -Dplughw -c2
Recording WAVE 'stdin' : Unsigned 8 bit, Rate 8000 Hz, Stereo
arecord: set_params:1116: Unable to install hw params:
ACCESS: RW_INTERLEAVED
FORMAT: U8
SUBFORMAT: STD
SAMPLE_BITS: 8
FRAME_BITS: 16
CHANNELS: 2
[...]

Root cause is, the driver is reporting 2-channel capture capability
that is not supported by the MRST hardware. So the plughw plugin
end up requesting 2-channel capture which fails.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
---

drivers/staging/intel_sst/intelmid.c | 7 +++++++
1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/drivers/staging/intel_sst/intelmid.c b/drivers/staging/intel_sst/intelmid.c
index 61ef4a6..0b9b1b6 100644
--- a/drivers/staging/intel_sst/intelmid.c
+++ b/drivers/staging/intel_sst/intelmid.c
@@ -335,6 +335,13 @@ static int snd_intelmad_open(struct snd_pcm_substream *substream,
runtime = substream->runtime;
/* set the runtime hw parameter with local snd_pcm_hardware struct */
runtime->hw = snd_intelmad_stream;
+ if (intelmaddata->cpu_id == CPU_CHIP_LINCROFT) {
+ /*
+ * MRST firmware currently denies stereo recording requests.
+ */
+ if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+ runtime->hw.channels_max = 1;
+ }
if (intelmaddata->cpu_id == CPU_CHIP_PENWELL) {
runtime->hw = snd_intelmad_stream;
runtime->hw.rates = SNDRV_PCM_RATE_48000;