Re: [PATCH] arm64: dts: qcom: add debug UART pins to reserved GPIO ranges on RB2

[Konrad Dybcio]

On 6/16/25 6:43 PM, Bartosz Golaszewski wrote:
> On Mon, Jun 16, 2025 at 6:20 PM Konrad Dybcio
> <konrad.dybcio@xxxxxxxxxxxxxxxx> wrote:
>>
>> On 6/16/25 4:33 PM, Bartosz Golaszewski wrote:
>>> From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
>>>
>>> GPIO12 and GPIO13 are used for the debug UART and must not be available
>>> to drivers or user-space. Add them to the gpio-reserved-ranges.
>>>
>>> Fixes: 8d58a8c0d930c ("arm64: dts: qcom: Add base qrb4210-rb2 board dts")
>>> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
>>> ---
>>
>> That also makes them unavailable to the kernel though, no?
>>
> 
> Yes. They could only be used by QUP - I2C or SPI #4 - on sm6115 but
> none of these are used on RB2. I just noticed that my console froze
> when I accidentally requested GPIO12 and figured that it makes sense
> to make them unavailable. Let me know if this should be dropped.

We usually carry an active/sleep pair of pinctrl configs - would they
be affected by these changes?

Konrad