Re: [PATCH 1/2] ASoC: rt711: remap buttons

[Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>]

On 6/17/21 8:27 AM, Mark Brown wrote:
> On Thu, Jun 17, 2021 at 01:19:05PM +0000, Shuming [范書銘] wrote:
> 
>>>> This patch uses the same mapping as the machine driver:
>>>> BTN_0 : KEY_PLAYPAUSE
>>>> BTN_1 : KEY_VOICECOMMAND
>>>> BTN_2 : KEY_VOLUMEUP
>>>> BTN_3 : KEY_VOLUMEDOWN
> 
>>> Which machine driver?  Can't there be multiple machine drivers, and if
>>> they're already overriding things why do this?
> 
>> The rt711 codec is designed in the Intel platform only for now.
> 
> I'm sure your sales team would be happy to change that!
> 
>> The machine driver is 'sof_sdw.c' that resides under sound/soc/intel/boards.
>> It seems Intel uses the same mapping in all other Intel machine drivers.
>> Please check the commit as below.
>> https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git/commit/?id=1f64a08bd5a9a218deb37c03c1e98e9567379698
> 
> Sure, but if the machine drivers for these platforms already do the
> right thing why change the CODEC driver?
> 
>> Hi Sathya,
>> Do you know why the m/c driver uses this mapping?
> 
> I'd guess it's just because that's the standard set of headphone buttons
> that Intel uses for their platforms.

Intel has no specific requirement, we just follow what the Google 4-button description says [1]

That said, I can't recall why half of the machine drivers follow one pattern and the other half a different one.

Same as spec:
sof_da7219_max98373.c:  snd_jack_set_key(jack->jack, SND_JACK_BTN_0, KEY_PLAYPAUSE);
sof_da7219_max98373.c-  snd_jack_set_key(jack->jack, SND_JACK_BTN_1, KEY_VOLUMEUP);
sof_da7219_max98373.c-  snd_jack_set_key(jack->jack, SND_JACK_BTN_2, KEY_VOLUMEDOWN);
sof_da7219_max98373.c-  snd_jack_set_key(jack->jack, SND_JACK_BTN_3, KEY_VOICECOMMAND);

sof_cs42l42.c:  snd_jack_set_key(jack->jack, SND_JACK_BTN_0, KEY_PLAYPAUSE);
sof_cs42l42.c-  snd_jack_set_key(jack->jack, SND_JACK_BTN_1, KEY_VOLUMEUP);
sof_cs42l42.c-  snd_jack_set_key(jack->jack, SND_JACK_BTN_2, KEY_VOLUMEDOWN);
sof_cs42l42.c-  snd_jack_set_key(jack->jack, SND_JACK_BTN_3, KEY_VOICECOMMAND);

swap wrt. spec:
sof_sdw_rt711.c:        snd_jack_set_key(jack->jack, SND_JACK_BTN_0, KEY_PLAYPAUSE);
sof_sdw_rt711.c-        snd_jack_set_key(jack->jack, SND_JACK_BTN_1, KEY_VOICECOMMAND);
sof_sdw_rt711.c-        snd_jack_set_key(jack->jack, SND_JACK_BTN_2, KEY_VOLUMEUP);
sof_sdw_rt711.c-        snd_jack_set_key(jack->jack, SND_JACK_BTN_3, KEY_VOLUMEDOWN);

kbl_rt5663_max98927.c:  snd_jack_set_key(jack->jack, SND_JACK_BTN_0, KEY_PLAYPAUSE);
kbl_rt5663_max98927.c-  snd_jack_set_key(jack->jack, SND_JACK_BTN_1, KEY_VOICECOMMAND);
kbl_rt5663_max98927.c-  snd_jack_set_key(jack->jack, SND_JACK_BTN_2, KEY_VOLUMEUP);
kbl_rt5663_max98927.c-  snd_jack_set_key(jack->jack, SND_JACK_BTN_3, KEY_VOLUMEDOWN);

Brent, Curtis, Jimmy, can you comment on the order?


[1] https://source.android.com/devices/accessories/headset/plug-headset-spec#control-function_mapping