[PATCH 4/6] ASoC: Intel: bytcr_rt5640: Add support for a second headphones output

[Hans de Goede]

Hi Pierre-Louis,

On 8/2/21 3:45 PM, Pierre-Louis Bossart wrote:
> 
> 
> On 8/1/21 4:04 PM, Hans de Goede wrote:
>> Some devices (HP Elitepad 1000 G2) have a second headphones output
>> (1 on the dock, 2nd on the tablet itself) which is implemented through
>> the line-out output of the codec combined with an external hp-amp
>> which gets enabled through the codec's GPIO1 pin.
>>
>> Add support for this through a new BYT_RT5640_LINEOUT_AS_HP2 quirk.
>>
>> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
>> ---
>>  sound/soc/intel/boards/bytcr_rt5640.c | 36 +++++++++++++++++++++++++--
>>  1 file changed, 34 insertions(+), 2 deletions(-)
>>
>> diff --git a/sound/soc/intel/boards/bytcr_rt5640.c b/sound/soc/intel/boards/bytcr_rt5640.c
>> index 70faba13450c..51fb44ad9b4b 100644
>> --- a/sound/soc/intel/boards/bytcr_rt5640.c
>> +++ b/sound/soc/intel/boards/bytcr_rt5640.c
>> @@ -74,6 +74,7 @@ enum {
>>  #define BYT_RT5640_MCLK_25MHZ		BIT(23)
>>  #define BYT_RT5640_NO_SPEAKERS		BIT(24)
>>  #define BYT_RT5640_LINEOUT		BIT(25)
>> +#define BYT_RT5640_LINEOUT_AS_HP2	BIT(26)
> 
> The definitions aren't fully clear to me. It seems that the two quirks
> above are mutually exclusive if I read the code below
> 
> +	if (byt_rt5640_quirk & BYT_RT5640_LINEOUT_AS_HP2)
> +		lineout_string = " cfg-hp2:lineout";
> +	else if (byt_rt5640_quirk & BYT_RT5640_LINEOUT)
>  		lineout_string = " cfg-lineout:1";
> 
> But in the following patch the two are mixed:
> 
> +		.driver_data = (void *)(BYT_RT5640_DMIC2_MAP |
> +					BYT_RT5640_MCLK_EN |
> +					BYT_RT5640_LINEOUT |
> +					BYT_RT5640_LINEOUT_AS_HP2 |
> +					BYT_RT5640_HSMIC2_ON_IN1),
> 
> so maybe the test above should be
> 
> if (byt_rt5640_quirk & BYT_RT5640_LINEOUT) {
> 	if (byt_rt5640_quirk & BYT_RT5640_LINEOUT_AS_HP2)
> 		lineout_string = " cfg-hp2:lineout";
> 	else
>  		lineout_string = " cfg-lineout:1";
> }

Right, I decided to first add plain line-out support (which may be
useful elsewhere) and then to build the hp2-out using external-amp connected
to lineout on top of that. So your suggestion to change the test to set
the lineout_string makes sense. I'll fix that for v2 of the patch-series.

> I am also not very clear on the hp2 support, is there any sort of jack
> detection or will this require always an explicit user choice?

Quoting from:

"""
I've also figured out how jack-detect works, since the codec's GPIO1 is used for the external-hp-amp enable, the jack-detect signals are directly connected to the Bay Trail SoC's GPIOs:

  -gpioget 'INT33FC:02' 14 && gpioget 'INT33FC:00' 0 && gpioget 'INT33FC:00' 3
   Nothing inserted: 1 1 0
   Headset  in dock: 0 1 0
   Headphon in dock: 0 1 1
   Headset  in tabl: 1 0 0
   Headphon in tabl: 1 0 0
   Conclusion:
   GPO2 pin 14: !jack in dock
   GPO0 pin  0: !jack in tablet
   GPO0 pin  3: 1 when jack in dock with no mic

And I believe that the mic on the tablet jack can be detected using the normal micBIAS over current detection which is normally also used.

This will require some special jack-detect handling inside the machine driver for this model. I plan to also add support for this when I have some time to work on this.
"""

So ATM this requires an explicit user-choice, but I plan to add support for
jack-detect on both jacks when I've some more time to work on this.

Regards,

Hans