Hi Laurent Thanks for the review. One question below. On 4/1/2022 8:38 AM, Laurent Pinchart wrote:
Hi Abhinav, Thank you for the patch. On Thu, Mar 31, 2022 at 05:12:13PM -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. changes in v6: - assign the encoder inside drm_writeback_connector_init_with_encoder() for better readability - improve some documentation for internal encoder Co-developed-by: Kandpal Suraj <suraj.kandpal@xxxxxxxxx> Signed-off-by: Kandpal Suraj <suraj.kandpal@xxxxxxxxx> Signed-off-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx> --- drivers/gpu/drm/drm_writeback.c | 18 ++++++++++++------ drivers/gpu/drm/vc4/vc4_txp.c | 14 ++++++++------ include/drm/drm_writeback.h | 21 +++++++++++++++++++--Please split this in two patches, one for the DRM core and one for the VC4 driver. This applies to most patches as a general rule, with the main exception being API refactoring that requires changing the implementation and all its users in a single patch.
I also wanted to do that but that would break compilation of this change because of vc4 (explained below) so I had to club it in this patch.
If you can provide some suggestion on how to address vc4's dependency I can break this up.
3 files changed, 39 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/drm_writeback.c b/drivers/gpu/drm/drm_writeback.c index 797223c..7f72109 100644 --- a/drivers/gpu/drm/drm_writeback.c +++ b/drivers/gpu/drm/drm_writeback.c @@ -179,21 +179,21 @@ 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;} @@ -238,6 +238,12 @@ 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.cindex 5e53f02..a9b4f83 100644 --- a/drivers/gpu/drm/vc4/vc4_txp.c +++ b/drivers/gpu/drm/vc4/vc4_txp.c @@ -151,6 +151,8 @@ struct vc4_txp {struct platform_device *pdev; + struct drm_encoder drm_enc;+ struct drm_writeback_connector connector;void __iomem *regs;@@ -159,7 +161,7 @@ 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);
vc4 directly references connector.encoder here.
+ return container_of(encoder, struct vc4_txp, drm_enc); }static inline struct vc4_txp *connector_to_vc4_txp(struct drm_connector *conn)@@ -499,9 +501,9 @@ static int vc4_txp_bind(struct device *dev, struct device *master, void *data)wb_conn = &txp->connector; - drm_encoder_helper_add(&wb_conn->encoder, &vc4_txp_encoder_helper_funcs);+ drm_encoder_helper_add(&txp->drm_enc, &vc4_txp_encoder_helper_funcs);- ret = drm_encoder_init(drm, &wb_conn->encoder,+ ret = drm_encoder_init(drm, &txp->drm_enc, &vc4_txp_encoder_funcs, DRM_MODE_ENCODER_VIRTUAL, NULL);@@ -511,10 +513,10 @@ static int vc4_txp_bind(struct device *dev, struct device *master, void *data)drm_connector_helper_add(&wb_conn->base, &vc4_txp_connector_helper_funcs);- ret = drm_writeback_connector_init_with_encoder(drm, wb_conn, &wb_conn->encoder,+ ret = drm_writeback_connector_init_with_encoder(drm, wb_conn, &txp->drm_enc, &vc4_txp_connector_funcs, drm_fmts, ARRAY_SIZE(drm_fmts)); if (ret) { - drm_encoder_cleanup(&wb_conn->encoder); + drm_encoder_cleanup(&txp->drm_enc); return ret; }@@ -523,7 +525,7 @@ static int vc4_txp_bind(struct device *dev, struct device *master, void *data)if (ret) return ret;- encoder = &txp->connector.encoder;
Also here.
+ 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 4795024..3f5c330 100644 --- a/include/drm/drm_writeback.h +++ b/include/drm/drm_writeback.h @@ -25,15 +25,32 @@ 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; + 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 internal_encoder; + /** * @pixel_formats_blob_ptr: * * DRM blob property data for the pixel formats list on writeback -- 2.7.4
