Matt Flax flatmax@flatmax.org writes:
This patch adds multitrack capability if in DSP mode A and the codec is master.
In bcm2835_i2s_startup, snd_pcm_hw_constraint_single is used to set channels to 8 if both SND_SOC_DAIFMT_CBM_CFM and SND_SOC_DAIFMT_DSP_A are set. Otherwise, channels are set to 2. These settings are accomplished using the SNDRV_PCM_HW_PARAM_CHANNELS variable.
In bcm2835_i2s_shutdown the channels are set to 2 by default.
In bcm2835_i2s_hw_params, DSP mode A format is now an option. Before replicating the format variable (from ch2 to ch1) for register loading, requested channels are checked to be either 2 or 8. This can be expanded later to accomodate other channel counts if supported by the sound card hardware.
Signed-off-by: Matt Flax flatmax@flatmax.org
Acked-by: Eric Anholt eric@anholt.net