From: Laurent Pinchart <laurent.pinchart@ideasonboard.com> To: dri-devel@lists.freedesktop.org Cc: devicetree@vger.kernel.org, Chen-Yu Tsai <wens@csie.org>, Rob Herring <robh+dt@kernel.org>, Daniel Vetter <daniel.vetter@intel.com>, Maxime Ripard <maxime.ripard@free-electrons.com>, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v3 1/4] drm/bridge: Add RGB to VGA bridge support Date: Sun, 18 Sep 2016 13:01:16 +0300 [thread overview] Message-ID: <2115773.yQojqqIjGI@avalon> (raw) In-Reply-To: <20160908121751.16911-2-maxime.ripard@free-electrons.com> Hi Maxime, Thank you for the patch. On Thursday 08 Sep 2016 14:17:48 Maxime Ripard wrote: > Some boards have an entirely passive RGB to VGA bridge, based on either > DACs or resistor ladders. > > Those might or might not have an i2c bus routed to the VGA connector in > order to access the screen EDIDs. > > Add a bridge that doesn't do anything but expose the modes available on the > screen, either based on the EDIDs if available, or based on the XGA > standards. > > Acked-by: Rob Herring <robh@kernel.org> > Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> > --- > .../bindings/display/bridge/rgb-to-vga-bridge.txt | 52 +++++ > drivers/gpu/drm/bridge/Kconfig | 6 + > drivers/gpu/drm/bridge/Makefile | 1 + > drivers/gpu/drm/bridge/rgb-to-vga.c | 232 ++++++++++++++++++ > 4 files changed, 291 insertions(+) > create mode 100644 > Documentation/devicetree/bindings/display/bridge/rgb-to-vga-bridge.txt > create mode 100644 drivers/gpu/drm/bridge/rgb-to-vga.c > > diff --git > a/Documentation/devicetree/bindings/display/bridge/rgb-to-vga-bridge.txt > b/Documentation/devicetree/bindings/display/bridge/rgb-to-vga-bridge.txt > new file mode 100644 > index 000000000000..83a053fb51a0 > --- /dev/null > +++ b/Documentation/devicetree/bindings/display/bridge/rgb-to-vga-bridge.txt > @@ -0,0 +1,52 @@ > +Passive RGB to VGA bridge > +------------------------- > + > +This binding is aimed for entirely passive RGB to VGA bridges that do not > +require any configuration. Couldn't it also support active RGB to VGA bridges that don't require any configuration ? It would seem a bit pointless to define a separate DT binding for them. > +Required properties: > + > +- compatible: Must be "rgb-to-vga-bridge" > + > +Required nodes: > + > +This device has two video ports. Their connections are modeled using the OF > +graph bindings specified in Documentation/devicetree/bindings/graph.txt. > + > +- Video port 0 for RGB input > +- Video port 1 for VGA output > + > + > +Example > +------- > + > +bridge { > + compatible = "rgb-to-vga-bridge"; > + #address-cells = <1>; > + #size-cells = <0>; > + > + ports { > + #address-cells = <1>; > + #size-cells = <0>; > + > + port@0 { > + #address-cells = <1>; > + #size-cells = <0>; > + reg = <0>; > + > + vga_bridge_in: endpoint { > + remote-endpoint = <&tcon0_out_vga>; > + }; > + }; > + > + port@1 { > + #address-cells = <1>; > + #size-cells = <0>; > + reg = <1>; > + > + vga_bridge_out: endpoint { > + remote-endpoint = <&vga_con_in>; > + }; > + }; > + }; > +}; > diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig > index b590e678052d..42b95adf5091 100644 > --- a/drivers/gpu/drm/bridge/Kconfig > +++ b/drivers/gpu/drm/bridge/Kconfig > @@ -17,6 +17,12 @@ config DRM_ANALOGIX_ANX78XX > the HDMI output of an application processor to MyDP > or DisplayPort. > > +config DRM_RGB_TO_VGA > + tristate "Dumb RGB to VGA Bridge support" > + select DRM_KMS_HELPER > + help > + Support for passive RGB to VGA bridges > + > config DRM_DW_HDMI > tristate > select DRM_KMS_HELPER > diff --git a/drivers/gpu/drm/bridge/Makefile > b/drivers/gpu/drm/bridge/Makefile index efdb07e878f5..3bb8cbe09fe9 100644 > --- a/drivers/gpu/drm/bridge/Makefile > +++ b/drivers/gpu/drm/bridge/Makefile > @@ -1,6 +1,7 @@ > ccflags-y := -Iinclude/drm > > obj-$(CONFIG_DRM_ANALOGIX_ANX78XX) += analogix-anx78xx.o > +obj-$(CONFIG_DRM_RGB_TO_VGA) += rgb-to-vga.o > obj-$(CONFIG_DRM_DW_HDMI) += dw-hdmi.o > obj-$(CONFIG_DRM_DW_HDMI_AHB_AUDIO) += dw-hdmi-ahb-audio.o > obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o > diff --git a/drivers/gpu/drm/bridge/rgb-to-vga.c > b/drivers/gpu/drm/bridge/rgb-to-vga.c new file mode 100644 > index 000000000000..84b1b10198a4 > --- /dev/null > +++ b/drivers/gpu/drm/bridge/rgb-to-vga.c > @@ -0,0 +1,232 @@ > + > +#include <linux/module.h> > +#include <linux/of_graph.h> > + > +#include <drm/drmP.h> > +#include <drm/drm_atomic_helper.h> > +#include <drm/drm_crtc.h> > +#include <drm/drm_crtc_helper.h> > + > +struct dumb_vga { > + struct drm_bridge bridge; > + struct drm_connector connector; > + > + struct i2c_adapter *ddc; > +}; > + > +static inline struct dumb_vga * > +drm_bridge_to_dumb_vga(struct drm_bridge *bridge) > +{ > + return container_of(bridge, struct dumb_vga, bridge); > +} > + > +static inline struct dumb_vga * > +drm_connector_to_dumb_vga(struct drm_connector *connector) > +{ > + return container_of(connector, struct dumb_vga, connector); > +} > + > +static int dumb_vga_get_modes(struct drm_connector *connector) > +{ > + struct dumb_vga *vga = drm_connector_to_dumb_vga(connector); > + struct edid *edid; > + int ret; > + > + if (IS_ERR(vga->ddc)) > + goto fallback; > + > + edid = drm_get_edid(connector, vga->ddc); > + if (!edid) { > + DRM_INFO("EDID readout failed, falling back to standard modes\n"); > + goto fallback; > + } > + > + drm_mode_connector_update_edid_property(connector, edid); > + return drm_add_edid_modes(connector, edid); > + > +fallback: > + /* > + * In case we cannot retrieve the EDIDs (broken or missing i2c > + * bus), fallback on the XGA standards > + */ > + ret = drm_add_modes_noedid(connector, 1920, 1200); > + > + /* And prefer a mode pretty much anyone can handle */ > + drm_set_preferred_mode(connector, 1024, 768); > + > + return ret; > +} > + > +static struct drm_encoder * > +dumb_vga_best_encoder(struct drm_connector *connector) > +{ > + struct dumb_vga *vga = drm_connector_to_dumb_vga(connector); > + > + return vga->bridge.encoder; > +} > + > +static struct drm_connector_helper_funcs dumb_vga_con_helper_funcs = { > + .get_modes = dumb_vga_get_modes, > + .best_encoder = dumb_vga_best_encoder, > +}; > + > +static enum drm_connector_status > +dumb_vga_connector_detect(struct drm_connector *connector, bool force) > +{ > + struct dumb_vga *vga = drm_connector_to_dumb_vga(connector); > + > + /* > + * Even if we have an I2C bus, we can't assume that the cable > + * is disconnected if drm_probe_ddc. Some cables don't wire > + * the DDC pins, or the I2C bus might be disfunctional. > + */ > + if (!IS_ERR(vga->ddc) && drm_probe_ddc(vga->ddc)) > + return connector_status_connected; > + > + return connector_status_unknown; > +} > + > +static void > +dumb_vga_connector_destroy(struct drm_connector *connector) > +{ > + drm_connector_cleanup(connector); > +} > + > +static struct drm_connector_funcs dumb_vga_con_funcs = { > + .dpms = drm_atomic_helper_connector_dpms, > + .detect = dumb_vga_connector_detect, > + .fill_modes = drm_helper_probe_single_connector_modes, > + .destroy = dumb_vga_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 dumb_vga_attach(struct drm_bridge *bridge) > +{ > + struct dumb_vga *vga = drm_bridge_to_dumb_vga(bridge); > + int ret; > + > + if (!bridge->encoder) { > + DRM_ERROR("Missing encoder\n"); > + return -ENODEV; > + } > + > + drm_connector_helper_add(&vga->connector, > + &dumb_vga_con_helper_funcs); > + ret = drm_connector_init(bridge->dev, &vga->connector, > + &dumb_vga_con_funcs, DRM_MODE_CONNECTOR_VGA); Bridges should really not create connectors. Fixing this problem is a bit out of scope for your patch, but I'm concerned that the growing number of bridge drivers will make it difficult to fix it later. > + if (ret) { > + DRM_ERROR("Failed to initialize connector\n"); > + return ret; > + } > + > + drm_mode_connector_attach_encoder(&vga->connector, > + bridge->encoder); > + > + return 0; > +} > + > +static void dumb_vga_nop(struct drm_bridge *bridge) {}; > + > +static struct drm_bridge_funcs dumb_vga_bridge_funcs = { > + .attach = dumb_vga_attach, > + .enable = dumb_vga_nop, > + .disable = dumb_vga_nop, > + .pre_enable = dumb_vga_nop, > + .post_disable = dumb_vga_nop, Those four operations are optional, you don't need dumb_vga_nop(). > +}; > + > +static struct i2c_adapter *dumb_vga_retrieve_ddc(struct device *dev) > +{ > + struct device_node *end_node, *phandle, *remote; > + struct i2c_adapter *ddc; > + > + end_node = of_graph_get_endpoint_by_regs(dev->of_node, 1, -1); > + if (!end_node) { > + dev_err(dev, "Missing connector endpoint\n"); > + return ERR_PTR(-ENODEV); > + } > + > + remote = of_graph_get_remote_port_parent(end_node); > + of_node_put(end_node); > + if (!remote) { > + dev_err(dev, "Enable to parse remote node\n"); > + return ERR_PTR(-EINVAL); > + } > + > + phandle = of_parse_phandle(remote, "ddc-i2c-bus", 0); > + of_node_put(remote); > + if (!phandle) > + return ERR_PTR(-ENODEV); > + > + ddc = of_get_i2c_adapter_by_node(phandle); > + of_node_put(phandle); > + if (!ddc) > + return ERR_PTR(-EPROBE_DEFER); > + > + return ddc; > +} > + > +static int dumb_vga_probe(struct platform_device *pdev) > +{ > + struct dumb_vga *vga; > + int ret; > + > + vga = devm_kzalloc(&pdev->dev, sizeof(*vga), GFP_KERNEL); > + if (!vga) > + return -ENOMEM; > + platform_set_drvdata(pdev, vga); > + > + vga->ddc = dumb_vga_retrieve_ddc(&pdev->dev); > + if (IS_ERR(vga->ddc)) { > + if (PTR_ERR(vga->ddc) == -ENODEV) { > + dev_info(&pdev->dev, > + "No i2c bus specified... Disabling EDID readout\n"); > + } else { > + dev_err(&pdev->dev, "Couldn't retrieve i2c bus\n"); > + return PTR_ERR(vga->ddc); > + } > + } > + > + vga->bridge.funcs = &dumb_vga_bridge_funcs; > + vga->bridge.of_node = pdev->dev.of_node; > + > + ret = drm_bridge_add(&vga->bridge); > + if (ret && !IS_ERR(vga->ddc)) > + i2c_put_adapter(vga->ddc); > + > + return ret; > +} > + > +static int dumb_vga_remove(struct platform_device *pdev) > +{ > + struct dumb_vga *vga = platform_get_drvdata(pdev); > + > + drm_bridge_remove(&vga->bridge); > + > + if (!IS_ERR(vga->ddc)) > + i2c_put_adapter(vga->ddc); > + > + return 0; > +} > + > +static const struct of_device_id dumb_vga_match[] = { > + { .compatible = "rgb-to-vga-bridge" }, > + {}, > +}; > +MODULE_DEVICE_TABLE(of, dumb_vga_match); > + > +struct platform_driver dumb_vga_driver = { > + .probe = dumb_vga_probe, > + .remove = dumb_vga_remove, > + .driver = { > + .name = "rgb-to-vga-bridge", > + .of_match_table = dumb_vga_match, > + }, > +}; > +module_platform_driver(dumb_vga_driver); > + > +MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); > +MODULE_DESCRIPTION("Dumb RGB to VGA bridge driver"); > +MODULE_LICENSE("GPL"); -- Regards, Laurent Pinchart _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
WARNING: multiple messages have this Message-ID (diff)
From: laurent.pinchart@ideasonboard.com (Laurent Pinchart) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v3 1/4] drm/bridge: Add RGB to VGA bridge support Date: Sun, 18 Sep 2016 13:01:16 +0300 [thread overview] Message-ID: <2115773.yQojqqIjGI@avalon> (raw) In-Reply-To: <20160908121751.16911-2-maxime.ripard@free-electrons.com> Hi Maxime, Thank you for the patch. On Thursday 08 Sep 2016 14:17:48 Maxime Ripard wrote: > Some boards have an entirely passive RGB to VGA bridge, based on either > DACs or resistor ladders. > > Those might or might not have an i2c bus routed to the VGA connector in > order to access the screen EDIDs. > > Add a bridge that doesn't do anything but expose the modes available on the > screen, either based on the EDIDs if available, or based on the XGA > standards. > > Acked-by: Rob Herring <robh@kernel.org> > Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> > --- > .../bindings/display/bridge/rgb-to-vga-bridge.txt | 52 +++++ > drivers/gpu/drm/bridge/Kconfig | 6 + > drivers/gpu/drm/bridge/Makefile | 1 + > drivers/gpu/drm/bridge/rgb-to-vga.c | 232 ++++++++++++++++++ > 4 files changed, 291 insertions(+) > create mode 100644 > Documentation/devicetree/bindings/display/bridge/rgb-to-vga-bridge.txt > create mode 100644 drivers/gpu/drm/bridge/rgb-to-vga.c > > diff --git > a/Documentation/devicetree/bindings/display/bridge/rgb-to-vga-bridge.txt > b/Documentation/devicetree/bindings/display/bridge/rgb-to-vga-bridge.txt > new file mode 100644 > index 000000000000..83a053fb51a0 > --- /dev/null > +++ b/Documentation/devicetree/bindings/display/bridge/rgb-to-vga-bridge.txt > @@ -0,0 +1,52 @@ > +Passive RGB to VGA bridge > +------------------------- > + > +This binding is aimed for entirely passive RGB to VGA bridges that do not > +require any configuration. Couldn't it also support active RGB to VGA bridges that don't require any configuration ? It would seem a bit pointless to define a separate DT binding for them. > +Required properties: > + > +- compatible: Must be "rgb-to-vga-bridge" > + > +Required nodes: > + > +This device has two video ports. Their connections are modeled using the OF > +graph bindings specified in Documentation/devicetree/bindings/graph.txt. > + > +- Video port 0 for RGB input > +- Video port 1 for VGA output > + > + > +Example > +------- > + > +bridge { > + compatible = "rgb-to-vga-bridge"; > + #address-cells = <1>; > + #size-cells = <0>; > + > + ports { > + #address-cells = <1>; > + #size-cells = <0>; > + > + port at 0 { > + #address-cells = <1>; > + #size-cells = <0>; > + reg = <0>; > + > + vga_bridge_in: endpoint { > + remote-endpoint = <&tcon0_out_vga>; > + }; > + }; > + > + port at 1 { > + #address-cells = <1>; > + #size-cells = <0>; > + reg = <1>; > + > + vga_bridge_out: endpoint { > + remote-endpoint = <&vga_con_in>; > + }; > + }; > + }; > +}; > diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig > index b590e678052d..42b95adf5091 100644 > --- a/drivers/gpu/drm/bridge/Kconfig > +++ b/drivers/gpu/drm/bridge/Kconfig > @@ -17,6 +17,12 @@ config DRM_ANALOGIX_ANX78XX > the HDMI output of an application processor to MyDP > or DisplayPort. > > +config DRM_RGB_TO_VGA > + tristate "Dumb RGB to VGA Bridge support" > + select DRM_KMS_HELPER > + help > + Support for passive RGB to VGA bridges > + > config DRM_DW_HDMI > tristate > select DRM_KMS_HELPER > diff --git a/drivers/gpu/drm/bridge/Makefile > b/drivers/gpu/drm/bridge/Makefile index efdb07e878f5..3bb8cbe09fe9 100644 > --- a/drivers/gpu/drm/bridge/Makefile > +++ b/drivers/gpu/drm/bridge/Makefile > @@ -1,6 +1,7 @@ > ccflags-y := -Iinclude/drm > > obj-$(CONFIG_DRM_ANALOGIX_ANX78XX) += analogix-anx78xx.o > +obj-$(CONFIG_DRM_RGB_TO_VGA) += rgb-to-vga.o > obj-$(CONFIG_DRM_DW_HDMI) += dw-hdmi.o > obj-$(CONFIG_DRM_DW_HDMI_AHB_AUDIO) += dw-hdmi-ahb-audio.o > obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o > diff --git a/drivers/gpu/drm/bridge/rgb-to-vga.c > b/drivers/gpu/drm/bridge/rgb-to-vga.c new file mode 100644 > index 000000000000..84b1b10198a4 > --- /dev/null > +++ b/drivers/gpu/drm/bridge/rgb-to-vga.c > @@ -0,0 +1,232 @@ > + > +#include <linux/module.h> > +#include <linux/of_graph.h> > + > +#include <drm/drmP.h> > +#include <drm/drm_atomic_helper.h> > +#include <drm/drm_crtc.h> > +#include <drm/drm_crtc_helper.h> > + > +struct dumb_vga { > + struct drm_bridge bridge; > + struct drm_connector connector; > + > + struct i2c_adapter *ddc; > +}; > + > +static inline struct dumb_vga * > +drm_bridge_to_dumb_vga(struct drm_bridge *bridge) > +{ > + return container_of(bridge, struct dumb_vga, bridge); > +} > + > +static inline struct dumb_vga * > +drm_connector_to_dumb_vga(struct drm_connector *connector) > +{ > + return container_of(connector, struct dumb_vga, connector); > +} > + > +static int dumb_vga_get_modes(struct drm_connector *connector) > +{ > + struct dumb_vga *vga = drm_connector_to_dumb_vga(connector); > + struct edid *edid; > + int ret; > + > + if (IS_ERR(vga->ddc)) > + goto fallback; > + > + edid = drm_get_edid(connector, vga->ddc); > + if (!edid) { > + DRM_INFO("EDID readout failed, falling back to standard modes\n"); > + goto fallback; > + } > + > + drm_mode_connector_update_edid_property(connector, edid); > + return drm_add_edid_modes(connector, edid); > + > +fallback: > + /* > + * In case we cannot retrieve the EDIDs (broken or missing i2c > + * bus), fallback on the XGA standards > + */ > + ret = drm_add_modes_noedid(connector, 1920, 1200); > + > + /* And prefer a mode pretty much anyone can handle */ > + drm_set_preferred_mode(connector, 1024, 768); > + > + return ret; > +} > + > +static struct drm_encoder * > +dumb_vga_best_encoder(struct drm_connector *connector) > +{ > + struct dumb_vga *vga = drm_connector_to_dumb_vga(connector); > + > + return vga->bridge.encoder; > +} > + > +static struct drm_connector_helper_funcs dumb_vga_con_helper_funcs = { > + .get_modes = dumb_vga_get_modes, > + .best_encoder = dumb_vga_best_encoder, > +}; > + > +static enum drm_connector_status > +dumb_vga_connector_detect(struct drm_connector *connector, bool force) > +{ > + struct dumb_vga *vga = drm_connector_to_dumb_vga(connector); > + > + /* > + * Even if we have an I2C bus, we can't assume that the cable > + * is disconnected if drm_probe_ddc. Some cables don't wire > + * the DDC pins, or the I2C bus might be disfunctional. > + */ > + if (!IS_ERR(vga->ddc) && drm_probe_ddc(vga->ddc)) > + return connector_status_connected; > + > + return connector_status_unknown; > +} > + > +static void > +dumb_vga_connector_destroy(struct drm_connector *connector) > +{ > + drm_connector_cleanup(connector); > +} > + > +static struct drm_connector_funcs dumb_vga_con_funcs = { > + .dpms = drm_atomic_helper_connector_dpms, > + .detect = dumb_vga_connector_detect, > + .fill_modes = drm_helper_probe_single_connector_modes, > + .destroy = dumb_vga_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 dumb_vga_attach(struct drm_bridge *bridge) > +{ > + struct dumb_vga *vga = drm_bridge_to_dumb_vga(bridge); > + int ret; > + > + if (!bridge->encoder) { > + DRM_ERROR("Missing encoder\n"); > + return -ENODEV; > + } > + > + drm_connector_helper_add(&vga->connector, > + &dumb_vga_con_helper_funcs); > + ret = drm_connector_init(bridge->dev, &vga->connector, > + &dumb_vga_con_funcs, DRM_MODE_CONNECTOR_VGA); Bridges should really not create connectors. Fixing this problem is a bit out of scope for your patch, but I'm concerned that the growing number of bridge drivers will make it difficult to fix it later. > + if (ret) { > + DRM_ERROR("Failed to initialize connector\n"); > + return ret; > + } > + > + drm_mode_connector_attach_encoder(&vga->connector, > + bridge->encoder); > + > + return 0; > +} > + > +static void dumb_vga_nop(struct drm_bridge *bridge) {}; > + > +static struct drm_bridge_funcs dumb_vga_bridge_funcs = { > + .attach = dumb_vga_attach, > + .enable = dumb_vga_nop, > + .disable = dumb_vga_nop, > + .pre_enable = dumb_vga_nop, > + .post_disable = dumb_vga_nop, Those four operations are optional, you don't need dumb_vga_nop(). > +}; > + > +static struct i2c_adapter *dumb_vga_retrieve_ddc(struct device *dev) > +{ > + struct device_node *end_node, *phandle, *remote; > + struct i2c_adapter *ddc; > + > + end_node = of_graph_get_endpoint_by_regs(dev->of_node, 1, -1); > + if (!end_node) { > + dev_err(dev, "Missing connector endpoint\n"); > + return ERR_PTR(-ENODEV); > + } > + > + remote = of_graph_get_remote_port_parent(end_node); > + of_node_put(end_node); > + if (!remote) { > + dev_err(dev, "Enable to parse remote node\n"); > + return ERR_PTR(-EINVAL); > + } > + > + phandle = of_parse_phandle(remote, "ddc-i2c-bus", 0); > + of_node_put(remote); > + if (!phandle) > + return ERR_PTR(-ENODEV); > + > + ddc = of_get_i2c_adapter_by_node(phandle); > + of_node_put(phandle); > + if (!ddc) > + return ERR_PTR(-EPROBE_DEFER); > + > + return ddc; > +} > + > +static int dumb_vga_probe(struct platform_device *pdev) > +{ > + struct dumb_vga *vga; > + int ret; > + > + vga = devm_kzalloc(&pdev->dev, sizeof(*vga), GFP_KERNEL); > + if (!vga) > + return -ENOMEM; > + platform_set_drvdata(pdev, vga); > + > + vga->ddc = dumb_vga_retrieve_ddc(&pdev->dev); > + if (IS_ERR(vga->ddc)) { > + if (PTR_ERR(vga->ddc) == -ENODEV) { > + dev_info(&pdev->dev, > + "No i2c bus specified... Disabling EDID readout\n"); > + } else { > + dev_err(&pdev->dev, "Couldn't retrieve i2c bus\n"); > + return PTR_ERR(vga->ddc); > + } > + } > + > + vga->bridge.funcs = &dumb_vga_bridge_funcs; > + vga->bridge.of_node = pdev->dev.of_node; > + > + ret = drm_bridge_add(&vga->bridge); > + if (ret && !IS_ERR(vga->ddc)) > + i2c_put_adapter(vga->ddc); > + > + return ret; > +} > + > +static int dumb_vga_remove(struct platform_device *pdev) > +{ > + struct dumb_vga *vga = platform_get_drvdata(pdev); > + > + drm_bridge_remove(&vga->bridge); > + > + if (!IS_ERR(vga->ddc)) > + i2c_put_adapter(vga->ddc); > + > + return 0; > +} > + > +static const struct of_device_id dumb_vga_match[] = { > + { .compatible = "rgb-to-vga-bridge" }, > + {}, > +}; > +MODULE_DEVICE_TABLE(of, dumb_vga_match); > + > +struct platform_driver dumb_vga_driver = { > + .probe = dumb_vga_probe, > + .remove = dumb_vga_remove, > + .driver = { > + .name = "rgb-to-vga-bridge", > + .of_match_table = dumb_vga_match, > + }, > +}; > +module_platform_driver(dumb_vga_driver); > + > +MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); > +MODULE_DESCRIPTION("Dumb RGB to VGA bridge driver"); > +MODULE_LICENSE("GPL"); -- Regards, Laurent Pinchart
next prev parent reply other threads:[~2016-09-18 10:01 UTC|newest] Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top 2016-09-08 12:17 [PATCH v3 0/4] drm: Add Support for Passive RGB to VGA bridges Maxime Ripard 2016-09-08 12:17 ` Maxime Ripard [not found] ` <20160908121751.16911-1-maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> 2016-09-08 12:17 ` [PATCH v3 1/4] drm/bridge: Add RGB to VGA bridge support Maxime Ripard 2016-09-08 12:17 ` Maxime Ripard [not found] ` <20160908121751.16911-2-maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> 2016-09-12 6:42 ` Chen-Yu Tsai 2016-09-12 6:42 ` Chen-Yu Tsai 2016-09-12 8:31 ` Archit Taneja 2016-09-12 8:31 ` Archit Taneja 2016-09-18 10:01 ` Laurent Pinchart [this message] 2016-09-18 10:01 ` Laurent Pinchart 2016-09-18 10:04 ` Laurent Pinchart 2016-09-18 10:04 ` Laurent Pinchart 2016-09-19 9:23 ` Maxime Ripard 2016-09-19 9:23 ` Maxime Ripard 2016-09-08 12:17 ` [PATCH v3 2/4] ARM: sun5i: a13-olinuxino: Enable VGA bridge Maxime Ripard 2016-09-08 12:17 ` Maxime Ripard [not found] ` <20160908121751.16911-3-maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> 2016-09-09 12:36 ` Chen-Yu Tsai 2016-09-09 12:36 ` Chen-Yu Tsai 2016-09-08 12:17 ` [PATCH v3 3/4] ARM: multi_v7: enable " Maxime Ripard 2016-09-08 12:17 ` Maxime Ripard 2016-09-08 12:17 ` [PATCH v3 4/4] ARM: sunxi: Enable " Maxime Ripard 2016-09-08 12:17 ` Maxime Ripard 2016-09-18 8:45 [PATCH v3 1/4] drm/bridge: Add RGB to VGA bridge support Meng Yi
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