Re: [PATCH v2 2/7] drm: ci: Force db410c to host mode

[Vignesh Raman <vignesh.raman@collabora.com>]

Hi Maxime,

On 05/09/23 17:27, Maxime Ripard wrote:
> On Tue, Sep 05, 2023 at 05:11:43PM +0530, Vignesh Raman wrote:
>>>> Also, that node actually has a label ("usb"), defined here:
>>>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom/msm8916.dtsi#n2322
>>>>
>>>> So you can end up with
>>>>
>>>> &usb {
>>>>           dr_mode = "host";
>>>> };
>>>
>>> ... which is the simplest and thus more robust one.
>>>
>>
>> Should it be,
>> &{/soc@0/usb} {
>> 	dr_mode = "host";
>> };
> 
> No. The &{/...} syntax refers to a path. &... refers to a label. They
> are not equivalent.

Sorry I was not clear before.

With,
&usb {
	dr_mode = "host";
};

The target is <0xffffffff> and fdtoverlay fails to apply the dtbo.

With,
&{/soc@0/usb} {
          dr_mode = "host";
};

The target-path is "/soc@0/usb" (usb: usb@78d9000)

/ {

	fragment@0 {
		target-path = "/soc@0/usb";

		__overlay__ {
			dr_mode = "host";
		};
	};
};

So will use  &{/...} syntax in this case.

Regards,
Vignesh