[PATCH 3/5] arm64: dts: rockchip: Fix mic-in-differential usage on rk3568-rock-3a

[Cristian Ciocaltea]

On 6/19/24 3:56 PM, Cristian Ciocaltea wrote:
> Hi Jonas,
> 
> On 6/19/24 3:22 PM, Jonas Karlman wrote:
>> Hi Cristian,
>>
>> On 2024-06-19 13:23, Cristian Ciocaltea wrote:
>>> The 'mic-in-differential' DT property supported by the RK809/RK817 audio
>>> codec driver is actually valid if prefixed with 'rockchip,':
>>>
>>>   DTC_CHK arch/arm64/boot/dts/rockchip/rk3568-rock-3a.dtb
>>>   rk3568-rock-3a.dtb: pmic at 20: codec: 'mic-in-differential' does not match any of the regexes: 'pinctrl-[0-9]+'
>>> 	from schema $id: http://devicetree.org/schemas/mfd/rockchip,rk809.yaml#
>>>
>>> Make use of the correct property name.
>>>
>>> Fixes: a84ffd2ef1ff ("arm64: dts: rockchip: Fix mic-in-differential usage on rock-3a")
>>> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea at collabora.com>
>>> ---
>>>  arch/arm64/boot/dts/rockchip/rk3568-rock-3a.dts | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/arch/arm64/boot/dts/rockchip/rk3568-rock-3a.dts b/arch/arm64/boot/dts/rockchip/rk3568-rock-3a.dts
>>> index ebdedea15ad1..0b54dfe92d6e 100644
>>> --- a/arch/arm64/boot/dts/rockchip/rk3568-rock-3a.dts
>>> +++ b/arch/arm64/boot/dts/rockchip/rk3568-rock-3a.dts
>>> @@ -533,7 +533,7 @@ regulator-state-mem {
>>>  		};
>>>  
>>>  		codec {
>>> -			mic-in-differential;
>>> +			rockchip,mic-in-differential;
>>
>> If I understand the schematics correctly, only one wire is connected so
>> this board cannot really use differential signaling, and this should
>> probably instead be dropped.
> 
> Thanks for pointing this out, I will drop it in v2.

I've also checked the schematics which indicate the PMIC RK809 CODEC
receives both MIC1_INN and MIC1_INP signals; the former comes from the
Jack input, while the latter is generated by the SLM42Q3AT MEMS Microphone.

However, I'm not sure the Mic presence on the board is dependent on the
HW revision - on REV V1.3 the "NC_" prefix under U24 component label
suggests it is not connected.  So maybe we should keep the property?!

Cristian