2023-07-02 10:35:44

by Raphael Gallais-Pou

Subject: [PATCH] ARM: dts: st: add buswidth property to stm32f429-disco

The ili9341 is left without a mandatory buswidth to properly communicate
between the SI bus and the display. Add the device-tree property.

Signed-off-by: Raphael Gallais-Pou <[email protected]>
---
arch/arm/boot/dts/stm32f429-disco.dts | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/arm/boot/dts/stm32f429-disco.dts b/arch/arm/boot/dts/stm32f429-disco.dts
index 3b81228d46a2..5eaf95afc8c7 100644
--- a/arch/arm/boot/dts/stm32f429-disco.dts
+++ b/arch/arm/boot/dts/stm32f429-disco.dts
@@ -197,6 +197,7 @@ display: display@1{
spi-3wire;
spi-max-frequency = <10000000>;
dc-gpios = <&gpiod 13 0>;
+ buswidth = <8>;
port {
panel_in_rgb: endpoint {
remote-endpoint = <&ltdc_out_rgb>;
--
2.41.0

2023-07-02 21:13:18

by Krzysztof Kozlowski

Subject: Re: [PATCH] ARM: dts: st: add buswidth property to stm32f429-disco

On 02/07/2023 12:35, Raphael Gallais-Pou wrote:
> The ili9341 is left without a mandatory buswidth to properly communicate
> between the SI bus and the display. Add the device-tree property.
>
> Signed-off-by: Raphael Gallais-Pou <[email protected]>
> ---
> arch/arm/boot/dts/stm32f429-disco.dts | 1 +

There is no such file. Please rebase on recent Linux.

> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm/boot/dts/stm32f429-disco.dts b/arch/arm/boot/dts/stm32f429-disco.dts
> index 3b81228d46a2..5eaf95afc8c7 100644
> --- a/arch/arm/boot/dts/stm32f429-disco.dts
> +++ b/arch/arm/boot/dts/stm32f429-disco.dts
> @@ -197,6 +197,7 @@ display: display@1{
> spi-3wire;
> spi-max-frequency = <10000000>;
> dc-gpios = <&gpiod 13 0>;
> + buswidth = <8>;

There is no such spi property.

Best regards,
Krzysztof

2023-07-03 03:24:11

by Raphael Gallais-Pou

Subject: Re: [PATCH] ARM: dts: st: add buswidth property to stm32f429-disco

Hi,

Le 02/07/2023 à 22:14, Krzysztof Kozlowski a écrit :
> On 02/07/2023 12:35, Raphael Gallais-Pou wrote:
>> The ili9341 is left without a mandatory buswidth to properly communicate
>> between the SI bus and the display. Add the device-tree property.
>>
>> Signed-off-by: Raphael Gallais-Pou <[email protected]>
>> ---
>> arch/arm/boot/dts/stm32f429-disco.dts | 1 +
>
> There is no such file. Please rebase on recent Linux.

Yes, indeed. I forgot to pull, I'm sorry.

>
>> 1 file changed, 1 insertion(+)
>>
>> diff --git a/arch/arm/boot/dts/stm32f429-disco.dts b/arch/arm/boot/dts/stm32f429-disco.dts
>> index 3b81228d46a2..5eaf95afc8c7 100644
>> --- a/arch/arm/boot/dts/stm32f429-disco.dts
>> +++ b/arch/arm/boot/dts/stm32f429-disco.dts
>> @@ -197,6 +197,7 @@ display: display@1{
>> spi-3wire;
>> spi-max-frequency = <10000000>;
>> dc-gpios = <&gpiod 13 0>;
>> + buswidth = <8>;
>
> There is no such spi property.

While I agree with you, I saw in staging drivers that this property was
fetch in the device-tree by the fbtft core.

Should I document those in or try to do it another way ?

>
> Best regards,
> Krzysztof
>

Thanks,
Raphaël

2023-07-03 07:33:44

by Krzysztof Kozlowski

Subject: Re: [PATCH] ARM: dts: st: add buswidth property to stm32f429-disco

On Mon, 3 Jul 2023 at 05:21, Raphaël Gallais-Pou <[email protected]> wrote:
> >> spi-3wire;
> >> spi-max-frequency = <10000000>;
> >> dc-gpios = <&gpiod 13 0>;
> >> + buswidth = <8>;
> >
> > There is no such spi property.
>
> While I agree with you, I saw in staging drivers that this property was
> fetch in the device-tree by the fbtft core.
>
> Should I document those in or try to do it another way ?

You cannot use undocumented properties. Whether this should be used at
all, depends what's this, why other properties cannot be used etc.