Hi Eric, On Thu, 11 May 2017 11:31:28 -0700 Eric Anholt <e...@anholt.net> wrote:
> This cuts 135 lines of boilerplate, at the cost of losing the > filtering of get_modes() using atmel_hlcdc_dc_mode_valid(). The > atomic check will still check that we don't set an invalid mode, > though. Nice. > > Signed-off-by: Eric Anholt <e...@anholt.net> Acked-by: Boris Brezillon <boris.brezil...@free-electrons.com> A few comments below (no need to address them, those are just minor things that can be fixed later on, or things I'm not comfortable with but cannot be addressed easily). > --- > > This patch is just a proposal for atmel-hlcdc if you like it -- maybe > you still want the filtering of get_modes(). I'm not sure from a > userspace API perspective if we should really have the encoder (your > CRTC's limits) filtering modes from a connector, but I'm also pretty > sure it doesn't actually matter. Actually I added this check because someone suggested it :-). I don't think it's a real problem, and that should definitely be checked at the CRTC level, not here. > > drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c | 163 > ++--------------------- > 1 file changed, 14 insertions(+), 149 deletions(-) > > diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c > b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c > index 4b2cfbd0d43f..340ef962aa81 100644 > --- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c > +++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c > @@ -23,191 +23,56 @@ > > #include <drm/drmP.h> > #include <drm/drm_of.h> > +#include <drm/drm_bridge.h> > > #include "atmel_hlcdc_dc.h" > > -/** > - * Atmel HLCDC RGB connector structure > - * > - * This structure stores RGB slave device information. > - * > - * @connector: DRM connector > - * @encoder: DRM encoder > - * @dc: pointer to the atmel_hlcdc_dc structure > - * @panel: panel connected on the RGB output > - */ > -struct atmel_hlcdc_rgb_output { > - struct drm_connector connector; > - struct drm_encoder encoder; > - struct atmel_hlcdc_dc *dc; > - struct drm_panel *panel; > -}; > - > -static inline struct atmel_hlcdc_rgb_output * > -drm_connector_to_atmel_hlcdc_rgb_output(struct drm_connector *connector) > -{ > - return container_of(connector, struct atmel_hlcdc_rgb_output, > - connector); > -} > - > -static inline struct atmel_hlcdc_rgb_output * > -drm_encoder_to_atmel_hlcdc_rgb_output(struct drm_encoder *encoder) > -{ > - return container_of(encoder, struct atmel_hlcdc_rgb_output, encoder); > -} > - > -static void atmel_hlcdc_rgb_encoder_enable(struct drm_encoder *encoder) > -{ > - struct atmel_hlcdc_rgb_output *rgb = > - drm_encoder_to_atmel_hlcdc_rgb_output(encoder); > - > - if (rgb->panel) { > - drm_panel_prepare(rgb->panel); > - drm_panel_enable(rgb->panel); > - } > -} > - > -static void atmel_hlcdc_rgb_encoder_disable(struct drm_encoder *encoder) > -{ > - struct atmel_hlcdc_rgb_output *rgb = > - drm_encoder_to_atmel_hlcdc_rgb_output(encoder); > - > - if (rgb->panel) { > - drm_panel_disable(rgb->panel); > - drm_panel_unprepare(rgb->panel); > - } > -} > - > -static const struct drm_encoder_helper_funcs > atmel_hlcdc_panel_encoder_helper_funcs = { > - .disable = atmel_hlcdc_rgb_encoder_disable, > - .enable = atmel_hlcdc_rgb_encoder_enable, > -}; > - > static const struct drm_encoder_funcs atmel_hlcdc_panel_encoder_funcs = { > .destroy = drm_encoder_cleanup, > }; > > -static int atmel_hlcdc_panel_get_modes(struct drm_connector *connector) > -{ > - struct atmel_hlcdc_rgb_output *rgb = > - drm_connector_to_atmel_hlcdc_rgb_output(connector); > - > - if (rgb->panel) > - return rgb->panel->funcs->get_modes(rgb->panel); > - > - return 0; > -} > - > -static int atmel_hlcdc_rgb_mode_valid(struct drm_connector *connector, > - struct drm_display_mode *mode) > -{ > - struct atmel_hlcdc_rgb_output *rgb = > - drm_connector_to_atmel_hlcdc_rgb_output(connector); > - > - return atmel_hlcdc_dc_mode_valid(rgb->dc, mode); > -} > - > -static const struct drm_connector_helper_funcs > atmel_hlcdc_panel_connector_helper_funcs = { > - .get_modes = atmel_hlcdc_panel_get_modes, > - .mode_valid = atmel_hlcdc_rgb_mode_valid, > -}; > - > -static enum drm_connector_status > -atmel_hlcdc_panel_connector_detect(struct drm_connector *connector, bool > force) > -{ > - struct atmel_hlcdc_rgb_output *rgb = > - drm_connector_to_atmel_hlcdc_rgb_output(connector); > - > - if (rgb->panel) > - return connector_status_connected; > - > - return connector_status_disconnected; > -} > - > -static void > -atmel_hlcdc_panel_connector_destroy(struct drm_connector *connector) > -{ > - struct atmel_hlcdc_rgb_output *rgb = > - drm_connector_to_atmel_hlcdc_rgb_output(connector); > - > - if (rgb->panel) > - drm_panel_detach(rgb->panel); > - > - drm_connector_cleanup(connector); > -} > - > -static const struct drm_connector_funcs atmel_hlcdc_panel_connector_funcs = { > - .dpms = drm_atomic_helper_connector_dpms, > - .detect = atmel_hlcdc_panel_connector_detect, > - .fill_modes = drm_helper_probe_single_connector_modes, > - .destroy = atmel_hlcdc_panel_connector_destroy, > - .reset = drm_atomic_helper_connector_reset, > - .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, > - .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, > -}; > - > static int atmel_hlcdc_attach_endpoint(struct drm_device *dev, > const struct device_node *np) > { > - struct atmel_hlcdc_dc *dc = dev->dev_private; > - struct atmel_hlcdc_rgb_output *output; > + struct drm_encoder *encoder; > struct drm_panel *panel; > struct drm_bridge *bridge; > int ret; > > - output = devm_kzalloc(dev->dev, sizeof(*output), GFP_KERNEL); > - if (!output) > + encoder = devm_kzalloc(dev->dev, sizeof(*encoder), GFP_KERNEL); > + if (!encoder) > return -EINVAL; > > - output->dc = dc; > - > - drm_encoder_helper_add(&output->encoder, > - &atmel_hlcdc_panel_encoder_helper_funcs); > - ret = drm_encoder_init(dev, &output->encoder, > + ret = drm_encoder_init(dev, encoder, > &atmel_hlcdc_panel_encoder_funcs, atmel_hlcdc_panel_encoder_funcs should probably be renamed atmel_hlcdc_dpi_encoder_funcs, but it's just a detail. > DRM_MODE_ENCODER_NONE, NULL); > if (ret) > return ret; > > - output->encoder.possible_crtcs = 0x1; > + encoder->possible_crtcs = 0x1; > > ret = drm_of_find_panel_or_bridge(np, 0, 0, &panel, &bridge); > if (ret) > return ret; > > if (panel) { > - output->connector.dpms = DRM_MODE_DPMS_OFF; > - output->connector.polled = DRM_CONNECTOR_POLL_CONNECT; > - drm_connector_helper_add(&output->connector, > - &atmel_hlcdc_panel_connector_helper_funcs); > - ret = drm_connector_init(dev, &output->connector, > - &atmel_hlcdc_panel_connector_funcs, > - DRM_MODE_CONNECTOR_Unknown); > - if (ret) > - goto err_encoder_cleanup; > - > - drm_mode_connector_attach_encoder(&output->connector, > - &output->encoder); > - > - ret = drm_panel_attach(panel, &output->connector); > - if (ret) { > - drm_connector_cleanup(&output->connector); > - goto err_encoder_cleanup; > - } > - > - output->panel = panel; > + bridge = drm_panel_bridge_add(panel, > DRM_MODE_CONNECTOR_Unknown); > + if (IS_ERR(bridge)) > + return PTR_ERR(bridge); It would even be simpler if panels were directly registering themselves to the bridge infrastructure so that they can be found with drm_of_find_bridge() and we don't have to explicitly create this bride->panel wrapper, but I remember that Thierry was not a big fan of this idea. Also, I keep thinking that we're abusing objects. A bridge is supposed to convert a pixel stream in a given format/encoding into a different format/encoding. Here, there's no conversion taking place in this panel_bridge, it's just a way to expose the panel as a generic element that can be easily connected to many display controller drivers. To be perfectly clear, I really like this idea of providing a generic wrapper, I'm just unsure exposing this wrapper as a bridge is such a good idea, unless we clarify the meaning/goal of a 'drm_bridge' object. The more I look at it, the more I think the drm_bridge is turning into a generic element that is taking a stream of pixel in a specific format and either consuming it of transforming it before forwarding it to the next element in the chain. Regards, Boris