pdm360ng and touchscreen set up

pdm360ng and touchscreen set up

[Dmitry Torokhov]

Hi Anatolij, Michael,

I hope you can shed some light for me: why does pdm360ng have very
elaborate set up for the "pendown" GPIO of the touchscreen? Can we
simply fix the DTS in arch/powerpc/boot/dts/pdm360ng.dts and specify
correct pendown GPIO there, as well as correct interrupt trigger,
and remove most of arch/powerpc/platforms/512x/pdm360ng.c ?

Something like this:

diff --git a/arch/powerpc/boot/dts/pdm360ng.dts b/arch/powerpc/boot/dts/pdm360ng.dts
index 67c3b9db75d7..5651bd9d9db3 100644
--- a/arch/powerpc/boot/dts/pdm360ng.dts
+++ b/arch/powerpc/boot/dts/pdm360ng.dts
@@ -176,11 +176,12 @@ psc@11900 {
 
 			/* ADS7845 touch screen controller */
 			ts@0 {
-				compatible = "ti,ads7846";
+				compatible = "ti,ads7845";
 				reg = <0x0>;
 				spi-max-frequency = <3000000>;
 				/* pen irq is GPIO25 */
-				interrupts = <78 0x8>;
+				interrupts = <78 IRQ_TYPE_LEVEL_LOW>;
+				pendown-gpios = <&gpio 25 GPIO_ACTIVE_LOW>;
 			};
 		};
 


The reason I'm asking is that I want to remove support for platform
data in ads7846 driver and pdm360ng is one of the last 3 users of it in
the kernel.

Thanks.

-- 
Dmitry

Re: pdm360ng and touchscreen set up

[Michael Ellerman]

Dmitry Torokhov <dmitry.torokhov@gmail.com> writes:
> Hi Anatolij, Michael,
>
> I hope you can shed some light for me: why does pdm360ng have very
> elaborate set up for the "pendown" GPIO of the touchscreen? Can we
> simply fix the DTS in arch/powerpc/boot/dts/pdm360ng.dts and specify
> correct pendown GPIO there, as well as correct interrupt trigger,
> and remove most of arch/powerpc/platforms/512x/pdm360ng.c ?

Sorry, I don't know anything about this platform.

It looks like it's some sort of embedded display device? It's pretty old
and hasn't seen much activity for ~10 years.

> Something like this:
>
> diff --git a/arch/powerpc/boot/dts/pdm360ng.dts b/arch/powerpc/boot/dts/pdm360ng.dts
> index 67c3b9db75d7..5651bd9d9db3 100644
> --- a/arch/powerpc/boot/dts/pdm360ng.dts
> +++ b/arch/powerpc/boot/dts/pdm360ng.dts
> @@ -176,11 +176,12 @@ psc@11900 {
>  
>  			/* ADS7845 touch screen controller */
>  			ts@0 {
> -				compatible = "ti,ads7846";
> +				compatible = "ti,ads7845";
>  				reg = <0x0>;
>  				spi-max-frequency = <3000000>;
>  				/* pen irq is GPIO25 */
> -				interrupts = <78 0x8>;
> +				interrupts = <78 IRQ_TYPE_LEVEL_LOW>;
> +				pendown-gpios = <&gpio 25 GPIO_ACTIVE_LOW>;
>  			};
>  		};
>  
>
>
> The reason I'm asking is that I want to remove support for platform
> data in ads7846 driver and pdm360ng is one of the last 3 users of it in
> the kernel.

I think go ahead with the change, and if anyone is still using this
device they can speak up if there's any problems.

cheers