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

[Cristian Ciocaltea]

On 6/21/24 9:58 AM, Jonas Karlman wrote:
> Hi Cristian,
> 
> On 2024-06-21 03:23, Cristian Ciocaltea wrote:
>> 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?!
> 
> There is no such mic on the board, at least on the rev 1.3 that I have.
> 
> This prop should be used to indicate that the attached microphone uses
> differential signaling, e.g. should have its two output signals
> connected to both INP(+) and INN(-).
> 
> The SLM42Q3AT or the single wire from headphone jack indicate that a
> single-ended microphone is/can be used/wired on this board.
> 
> The current use of non-working mic-in-differential was wrong, adding
> the rockchip,mic-in-differential would change behavior and wrongly
> describe hw of this board.

Thanks a lot for the clarifications! I dropped this in v2.

Regards,
Cristian