Hi Abhinav, Sorry for the delay in reviewing this, Easter break happened in between.
On Fri, Apr 08, 2022 at 05:53:54PM -0700, Abhinav Kumar wrote: > For some vendor driver implementations, display hardware can > be shared between the encoder used for writeback and the physical > display. > > In addition resources such as clocks and interrupts can > also be shared between writeback and the real encoder. > > To accommodate such vendor drivers and hardware, allow > real encoder to be passed for drm_writeback_connector. > > For existing clients, drm_writeback_connector_init() will use > an internal_encoder under the hood and hence no changes will > be needed. > > changes in v7: > - move this change before the vc4 change in the series > to minimize the changes to vendor drivers in drm core > changes > > Signed-off-by: Abhinav Kumar <quic_abhin...@quicinc.com> > --- > drivers/gpu/drm/drm_writeback.c | 18 ++++++++++++------ > drivers/gpu/drm/vc4/vc4_txp.c | 4 ++-- > include/drm/drm_writeback.h | 22 ++++++++++++++++++++-- > 3 files changed, 34 insertions(+), 10 deletions(-) > > diff --git a/drivers/gpu/drm/drm_writeback.c b/drivers/gpu/drm/drm_writeback.c > index 92658ad..0538674 100644 > --- a/drivers/gpu/drm/drm_writeback.c > +++ b/drivers/gpu/drm/drm_writeback.c > @@ -180,21 +180,21 @@ int drm_writeback_connector_init(struct drm_device *dev, > { > int ret = 0; > > - drm_encoder_helper_add(&wb_connector->encoder, enc_helper_funcs); > + drm_encoder_helper_add(&wb_connector->internal_encoder, > enc_helper_funcs); > > - wb_connector->encoder.possible_crtcs = possible_crtcs; > + wb_connector->internal_encoder.possible_crtcs = possible_crtcs; > > - ret = drm_encoder_init(dev, &wb_connector->encoder, > + ret = drm_encoder_init(dev, &wb_connector->internal_encoder, > &drm_writeback_encoder_funcs, > DRM_MODE_ENCODER_VIRTUAL, NULL); > if (ret) > return ret; > > - ret = drm_writeback_connector_init_with_encoder(dev, wb_connector, > &wb_connector->encoder, > - con_funcs, formats, n_formats); > + ret = drm_writeback_connector_init_with_encoder(dev, wb_connector, > + &wb_connector->internal_encoder, con_funcs, formats, > n_formats); > > if (ret) > - drm_encoder_cleanup(&wb_connector->encoder); > + drm_encoder_cleanup(&wb_connector->internal_encoder); > > return ret; > } > @@ -239,6 +239,12 @@ int drm_writeback_connector_init_with_encoder(struct > drm_device *dev, > struct drm_mode_config *config = &dev->mode_config; > int ret = create_writeback_properties(dev); > > + /* > + * Assign the encoder passed to this API to the wb_connector's encoder. > + * For drm_writeback_connector_init(), this shall be the > internal_encoder > + */ > + wb_connector->encoder = enc; > + > if (ret != 0) > return ret; > > diff --git a/drivers/gpu/drm/vc4/vc4_txp.c b/drivers/gpu/drm/vc4/vc4_txp.c > index 3447eb6..7e063a9 100644 > --- a/drivers/gpu/drm/vc4/vc4_txp.c > +++ b/drivers/gpu/drm/vc4/vc4_txp.c > @@ -159,7 +159,7 @@ struct vc4_txp { > > static inline struct vc4_txp *encoder_to_vc4_txp(struct drm_encoder *encoder) > { > - return container_of(encoder, struct vc4_txp, connector.encoder); > + return container_of(encoder, struct vc4_txp, > connector.internal_encoder); This doesn't feel right. First, vc4_txp should not be aware of the existance of internal_encoder, that is only for the use of drm_writeback_connector when someone doesn't pass on an encoder. Second, how do we know someone didn't actually use the 'encoder' pointer from drm_writeback_connector? I think we should be consistent and only use encoder member. Best regards, Liviu > } > > static inline struct vc4_txp *connector_to_vc4_txp(struct drm_connector > *conn) > @@ -507,7 +507,7 @@ static int vc4_txp_bind(struct device *dev, struct device > *master, void *data) > if (ret) > return ret; > > - encoder = &txp->connector.encoder; > + encoder = txp->connector.encoder; > encoder->possible_crtcs = drm_crtc_mask(crtc); > > ret = devm_request_irq(dev, irq, vc4_txp_interrupt, 0, > diff --git a/include/drm/drm_writeback.h b/include/drm/drm_writeback.h > index bb306fa..3fbae9d 100644 > --- a/include/drm/drm_writeback.h > +++ b/include/drm/drm_writeback.h > @@ -25,13 +25,31 @@ struct drm_writeback_connector { > struct drm_connector base; > > /** > - * @encoder: Internal encoder used by the connector to fulfill > + * @encoder: handle to drm_encoder used by the connector to fulfill > * the DRM framework requirements. The users of the > * @drm_writeback_connector control the behaviour of the @encoder > * by passing the @enc_funcs parameter to drm_writeback_connector_init() > * function. > + * > + * For some vendor drivers, the hardware resources are shared between > + * writeback encoder and rest of the display pipeline. > + * To accommodate such cases, encoder is a handle to the real encoder > + * hardware. > + * > + * For current existing writeback users, this shall continue to be the > + * embedded encoder for the writeback connector. > + */ > + struct drm_encoder *encoder; > + > + /** > + * @internal_encoder: internal encoder used by writeback when > + * drm_writeback_connector_init() is used. > + * @encoder will be assigned to this for those cases > + * > + * This will be unused when drm_writeback_connector_init_with_encoder() > + * is used. > */ > - struct drm_encoder encoder; > + struct drm_encoder internal_encoder; > > /** > * @pixel_formats_blob_ptr: > -- > 2.7.4 > -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯