[PATCH 10/10] arm64: dts: qcom: sdm845-google: Add STM FTS touchscreen support

[David Heidelberg]

On 02/03/2026 12:06, Konrad Dybcio wrote:
> On 3/1/26 6:51 PM, David Heidelberg via B4 Relay wrote:
>> From: Petr Hodina <petr.hodina at protonmail.com>
>>
>> Basic touchscreen connected to second i2c bus.
>>
>> Signed-off-by: Petr Hodina <petr.hodina at protonmail.com>
>> Co-developed-by: David Heidelberg <david at ixit.cz>
>> Signed-off-by: David Heidelberg <david at ixit.cz>
>> ---
>>   arch/arm64/boot/dts/qcom/sdm845-google-blueline.dts | 21 ++++++++++++++++++++-
>>   1 file changed, 20 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/sdm845-google-blueline.dts b/arch/arm64/boot/dts/qcom/sdm845-google-blueline.dts
>> index fa89be500fb85..2501104b06e1b 100644
>> --- a/arch/arm64/boot/dts/qcom/sdm845-google-blueline.dts
>> +++ b/arch/arm64/boot/dts/qcom/sdm845-google-blueline.dts
>> @@ -26,7 +26,26 @@ &i2c2 {
>>   
>>   	status = "okay";
>>   
>> -	/* ST,FTS @ 49 */
>> +	touchscreen at 49 {
>> +		compatible = "st,stmfts5";
>> +		reg = <0x49>;
>> +
>> +		pinctrl-0 = <&touchscreen_pins &touchscreen_reset>;
>> +		pinctrl-names = "default";
>> +
>> +		interrupt-parent = <&tlmm>;
>> +		interrupts = <125 IRQ_TYPE_LEVEL_LOW>;
>> +
>> +		irq-gpios = <&tlmm 125 GPIO_ACTIVE_HIGH>;
> 
> This is an anti-pattern - you can translate the GPIO handle to an
> IRQ handle, but unless the hardware is spectacularly odd, an interrupt
> reference is usually what you're after

Thanks, dropped in follow-up version.

> 
>> +		switch-gpios = <&tlmm 136 GPIO_ACTIVE_HIGH>;
>> +		reset-gpios = <&tlmm 99 GPIO_ACTIVE_LOW>;
>> +
>> +		avdd-supply = <&vreg_l14a_1p8>;
>> +		vdd-supply = <&vreg_l19a_3p3>;
>> +
>> +		touchscreen-size-x = <1079>;
>> +		touchscreen-size-y = <2159>;
> 
> Are you sure about these off-by-ones?

These we're extracted from st,maxcoords and yet, it should be 1080, 2160. Fixed 
in follow-up version.

Thanks
David

> 
> FWIW
> 
> input/touchscreen.c:
> 
> touchscreen_get_prop_u32(dev, "touchscreen-size-x",
>                           input_abs_get_max(input,
>                                             axis_x) + 1,
> 
> 				            notice ^
> 
> Konrad

-- 
David Heidelberg