Re: [PATCH v2 08/12] drm/bridge: parade-ps8640: select DRM_PANEL_BRIDGE

["Luca Ceresoli" <luca.ceresoli@bootlin.com>]

Hi,

On Thu Aug 27, 2026 at 6:23 PM CEST, Doug Anderson wrote:
> Hi,
>
> On Tue, Aug 25, 2026 at 3:11 AM Luca Ceresoli <luca.ceresoli@bootlin.com> wrote:
>>
>> This driver uses the drm_panel_bridge API and not the drm_panel API so it
>> should select DRM_PANEL_BRIDGE and not DRM_PANEL.
>
> Which exact "drm_panel_bridge" API does it use? I don't see any...

It calls devm_drm_of_get_bridge() [0], which is in bridge/panel.c [1],
which is enabled by CONFIG_DRM_PANEL_BRIDGE [2].

[0] https://elixir.bootlin.com/linux/v7.2.2/source/drivers/gpu/drm/bridge/parade-ps8640.c#L636
[1] https://elixir.bootlin.com/linux/v7.2.2/source/drivers/gpu/drm/bridge/panel.c#L483-L515
[2] https://elixir.bootlin.com/linux/v7.2.2/source/drivers/gpu/drm/Makefile#L159

> Certainly it's highly likely that the next bridge in the chain is a
> panel, but there are no API calls that I see. Maybe the scripts got
> confused because the variable name didn't get updated in commit

No script, just this humble human got confused X-)

> 5486eac81004 ("drm/bridge: parade-ps8640: switch to
> devm_drm_of_get_bridge") ?

Luca

--
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com