Re: [PATCH v2 02/11] drm/bridge: add of_drm_get_bridge_by_endpoint()

Dmitry Baryshkov
2026-04-28T11:30:54Z

On Tue, Apr 28, 2026 at 11:15:48AM +0200, Luca Ceresoli wrote:
> drm_of_find_panel_or_bridge() is widely used, but many callers pass NULL
> into the @panel or the @bridge arguments, thus making a very partial usage
> of this rather complex function.
>
> Besides, the bridge returned in @bridge is not refcounted, thus making this
> API unsafe when DRM bridge hotplug will be introduced.
>
> Solve both issues for the cases of calls to drm_of_find_panel_or_bridge()
> with a NULL @panel pointer by adding a new function that only looks for
> bridges (and is thus much simpler) and increments the refcount of the
> returned bridge.
>
> The new function is identical to drm_of_find_panel_or_bridge() except it:
>
> - handles bridge refcounting: uses of_drm_find_and_get_bridge() instead of
> of_drm_find_bridge() internally to return a refcounted bridge
> - is simpler to use: just takes no @panel parameter, returns the pointer
> in the return value instead of a double pointer argument
> - has a simpler implementation: it is equal to
> drm_of_find_panel_or_bridge() after removing the code that becomes dead
> when @panel == NULL
>
> Also add this function to drm_bridge.c and not drm_of.c because it returns
> bridges only.
>
> Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
>
> ---
>

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

--
With best wishes
Dmitry