[Sound-open-firmware] [PATCH 4/8] ssp: switch dai format form PCM B mode to normal I2S mode

[Pierre-Louis Bossart]

On 12/20/16 8:56 AM, Jie, Yang wrote:
>> -----Original Message-----
>> From: Pierre-Louis Bossart [mailto:pierre-louis.bossart at linux.intel.com]
>> Sent: Tuesday, December 20, 2016 10:31 PM
>> To: Keyon Jie <yang.jie at linux.intel.com>; sound-open-firmware at alsa-
>> project.org; liam.r.girdwood at linux.intel.com
>> Cc: Zhang, Keqiao <keqiao.zhang at intel.com>; Jie, Yang <yang.jie at intel.com>;
>> Ingalsuo, Seppo <seppo.ingalsuo at intel.com>; Lin, Mengdong
>> <mengdong.lin at intel.com>
>> Subject: Re: [Sound-open-firmware] [PATCH 4/8] ssp: switch dai format form
>> PCM B mode to normal I2S mode
>>
>> On 12/20/16 1:46 AM, Keyon Jie wrote:
>>> it is configured from host/codec side that using I2S mode, so switch
>>> it.
>>> ---
>>>  src/ipc/intel-ipc.c | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/src/ipc/intel-ipc.c b/src/ipc/intel-ipc.c index
>>> 16a906b..b159980 100644
>>> --- a/src/ipc/intel-ipc.c
>>> +++ b/src/ipc/intel-ipc.c
>>> @@ -562,7 +562,7 @@ static uint32_t ipc_device_set_formats(uint32_t
>>> header)
>>>
>>>  	/* setup the DAI HW config - TODO hard coded due to IPC limitations */
>>>  	dai_dev->dai_config.mclk = config_req.clock_frequency;
>>> -	dai_dev->dai_config.format = DAI_FMT_DSP_B | DAI_FMT_CONT |
>>> +	dai_dev->dai_config.format = DAI_FMT_I2S | DAI_FMT_CONT |
>>>  		DAI_FMT_NB_NF | DAI_FMT_CBS_CFS;
>>>  	dai_dev->dai_config.frame_size = 32;	/* TODO 16bit stereo hard
>> coded */
>>>  	dai_dev->dai_config.bclk_fs = 32;	/* 32 BCLKs per frame - */
>>>
>>
>> Why are we doing this? If we want to be compatible with existing machine
>> drivers you will want to support DSP_B with 4 slots, so this needs to be
>> programmable.
>
> Hi Pierre,
> You can see that the latest bytcr_rt5640.c is using I2S mode:
> ...
> 	.dai_fmt = SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_NF
> 						| SND_SOC_DAIFMT_CBS_CFS,
> ...
> https://git.kernel.org/cgit/linux/kernel/git/broonie/sound.git/tree/sound/soc/intel/boards/bytcr_rt5640.c?h=for-next
>
> we will add IPC to support this programmable next step.

Look at the machine drivers for rt5645, 70, they use 4 slots.