On Fri, 7 Feb 2025 05:03:13 +0200 Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> wrote: > On Thu, Feb 06, 2025 at 07:14:28PM +0100, Luca Ceresoli wrote: > > Supporting hardware whose final part of the DRM pipeline can be physically > > removed requires the ability to detach all bridges from a given point to > > the end of the pipeline. > > > > Introduce a variant of drm_encoder_cleanup() for this. > > > > Signed-off-by: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx> > > > > --- > > > > Changes in v6: none > > Changes in v5: none > > Changes in v4: none > > Changes in v3: none > > > > Changed in v2: > > - fix a typo in a comment > > --- > > drivers/gpu/drm/drm_encoder.c | 21 +++++++++++++++++++++ > > include/drm/drm_encoder.h | 1 + > > 2 files changed, 22 insertions(+) > > > > diff --git a/drivers/gpu/drm/drm_encoder.c b/drivers/gpu/drm/drm_encoder.c > > index 8f2bc6a28482229fd0b030a1958f87753ad7885f..472dfbefe2960924a4e83bec425af8c7ef5f5265 100644 > > --- a/drivers/gpu/drm/drm_encoder.c > > +++ b/drivers/gpu/drm/drm_encoder.c > > @@ -207,6 +207,27 @@ void drm_encoder_cleanup(struct drm_encoder *encoder) > > } > > EXPORT_SYMBOL(drm_encoder_cleanup); > > > > +/** > > + * drm_encoder_cleanup_from - remove a given bridge and all the following > > + * @encoder: encoder whole list of bridges shall be pruned > > + * @bridge: first bridge to remove > > + * > > + * Removes from an encoder all the bridges starting with a given bridge > > + * and until the end of the chain. > > + * > > + * This should not be used in "normal" DRM pipelines. It is only useful for > > + * devices whose final part of the DRM chain can be physically removed and > > + * later reconnected (possibly with different hardware). > > + */ > > +void drm_encoder_cleanup_from(struct drm_encoder *encoder, struct drm_bridge *bridge) > > +{ > > + struct drm_bridge *next; > > + > > + list_for_each_entry_safe_from(bridge, next, &encoder->bridge_chain, chain_node) > > + drm_bridge_detach(bridge); > > +} > > +EXPORT_SYMBOL(drm_encoder_cleanup_from); > > Shouldn't drm_encoder_cleanup() also use this function? Sure. I'll do it in v7. Luca -- Luca Ceresoli, Bootlin Embedded Linux and Kernel engineering https://bootlin.com