Commit 6b4468b0 authored by Dmitry Baryshkov's avatar Dmitry Baryshkov
Browse files

drm/bridge-connector: implement glue code for HDMI connector 



In order to let bridge chains implement HDMI connector infrastructure,
add necessary glue code to the drm_bridge_connector. In case there is a
bridge that sets DRM_BRIDGE_OP_HDMI, drm_bridge_connector will register
itself as a HDMI connector and provide proxy drm_connector_hdmi_funcs
implementation.

Note, to simplify implementation, there can be only one bridge in a
chain that sets DRM_BRIDGE_OP_HDMI. Setting more than one is considered
an error. This limitation can be lifted later, if the need arises.

Acked-by: default avatarMaxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240607-bridge-hdmi-connector-v5-3-ab384e6021af@linaro.org


Signed-off-by: default avatarDmitry Baryshkov <dmitry.baryshkov@linaro.org>
parent c12907be

drivers/gpu/drm/drm_bridge_connector.c

+91 −3
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ 
#include <drm/drm_managed.h>

#include <drm/drm_modeset_helper_vtables.h>

#include <drm/drm_probe_helper.h>

#include <drm/display/drm_hdmi_state_helper.h>



/**

 * DOC: overview
@@ -87,6 +88,13 @@ struct drm_bridge_connector { 
	 * connector modes detection, if any (see &DRM_BRIDGE_OP_MODES).

	 */

	struct drm_bridge *bridge_modes;

	/**

	 * @bridge_hdmi:

	 *

	 * The bridge in the chain that implements necessary support for the

	 * HDMI connector infrastructure, if any (see &DRM_BRIDGE_OP_HDMI).

	 */

	struct drm_bridge *bridge_hdmi;

};



#define to_drm_bridge_connector(x) \
@@ -287,6 +295,60 @@ static const struct drm_connector_helper_funcs drm_bridge_connector_helper_funcs 
	.disable_hpd = drm_bridge_connector_disable_hpd,

};



static enum drm_mode_status

drm_bridge_connector_tmds_char_rate_valid(const struct drm_connector *connector,

					  const struct drm_display_mode *mode,

					  unsigned long long tmds_rate)

{

	struct drm_bridge_connector *bridge_connector =

		to_drm_bridge_connector(connector);

	struct drm_bridge *bridge;



	bridge = bridge_connector->bridge_hdmi;

	if (!bridge)

		return MODE_ERROR;



	if (bridge->funcs->hdmi_tmds_char_rate_valid)

		return bridge->funcs->hdmi_tmds_char_rate_valid(bridge, mode, tmds_rate);

	else

		return MODE_OK;

}



static int drm_bridge_connector_clear_infoframe(struct drm_connector *connector,

						enum hdmi_infoframe_type type)

{

	struct drm_bridge_connector *bridge_connector =

		to_drm_bridge_connector(connector);

	struct drm_bridge *bridge;



	bridge = bridge_connector->bridge_hdmi;

	if (!bridge)

		return -EINVAL;



	return bridge->funcs->hdmi_clear_infoframe(bridge, type);

}



static int drm_bridge_connector_write_infoframe(struct drm_connector *connector,

						enum hdmi_infoframe_type type,

						const u8 *buffer, size_t len)

{

	struct drm_bridge_connector *bridge_connector =

		to_drm_bridge_connector(connector);

	struct drm_bridge *bridge;



	bridge = bridge_connector->bridge_hdmi;

	if (!bridge)

		return -EINVAL;



	return bridge->funcs->hdmi_write_infoframe(bridge, type, buffer, len);

}



static const struct drm_connector_hdmi_funcs drm_bridge_connector_hdmi_funcs = {

	.tmds_char_rate_valid = drm_bridge_connector_tmds_char_rate_valid,

	.clear_infoframe = drm_bridge_connector_clear_infoframe,

	.write_infoframe = drm_bridge_connector_write_infoframe,

};



/* -----------------------------------------------------------------------------

 * Bridge Connector Initialisation

 */
@@ -312,6 +374,8 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm, 
	struct drm_connector *connector;

	struct i2c_adapter *ddc = NULL;

	struct drm_bridge *bridge, *panel_bridge = NULL;

	unsigned int supported_formats = BIT(HDMI_COLORSPACE_RGB);

	unsigned int max_bpc = 8;

	int connector_type;

	int ret;
@@ -348,6 +412,20 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm, 
			bridge_connector->bridge_detect = bridge;

		if (bridge->ops & DRM_BRIDGE_OP_MODES)

			bridge_connector->bridge_modes = bridge;

		if (bridge->ops & DRM_BRIDGE_OP_HDMI) {

			if (bridge_connector->bridge_hdmi)

				return ERR_PTR(-EBUSY);

			if (!bridge->funcs->hdmi_write_infoframe ||

			    !bridge->funcs->hdmi_clear_infoframe)

				return ERR_PTR(-EINVAL);



			bridge_connector->bridge_hdmi = bridge;



			if (bridge->supported_formats)

				supported_formats = bridge->supported_formats;

			if (bridge->max_bpc)

				max_bpc = bridge->max_bpc;

		}



		if (!drm_bridge_get_next_bridge(bridge))

			connector_type = bridge->type;
@@ -370,6 +448,16 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm, 
		return ERR_PTR(-EINVAL);

	}



	if (bridge_connector->bridge_hdmi)

		ret = drmm_connector_hdmi_init(drm, connector,

					       bridge_connector->bridge_hdmi->vendor,

					       bridge_connector->bridge_hdmi->product,

					       &drm_bridge_connector_funcs,

					       &drm_bridge_connector_hdmi_funcs,

					       connector_type, ddc,

					       supported_formats,

					       max_bpc);

	else

		ret = drmm_connector_init(drm, connector,

					  &drm_bridge_connector_funcs,

					  connector_type, ddc);

drivers/gpu/drm/drm_debugfs.c

+2 −0
Original line number Diff line number Diff line
@@ -762,6 +762,8 @@ static int bridges_show(struct seq_file *m, void *data) 
			drm_puts(&p, " hpd");

		if (bridge->ops & DRM_BRIDGE_OP_MODES)

			drm_puts(&p, " modes");

		if (bridge->ops & DRM_BRIDGE_OP_HDMI)

			drm_puts(&p, " hdmi");

		drm_puts(&p, "\n");

	}

include/drm/drm_bridge.h

+81 −0
Original line number Diff line number Diff line
@@ -630,6 +630,52 @@ struct drm_bridge_funcs { 
	 */

	void (*hpd_disable)(struct drm_bridge *bridge);



	/**

	 * @hdmi_tmds_char_rate_valid:

	 *

	 * Check whether a particular TMDS character rate is supported by the

	 * driver.

	 *

	 * This callback is optional and should only be implemented by the

	 * bridges that take part in the HDMI connector implementation. Bridges

	 * that implement it shall set the DRM_BRIDGE_OP_HDMI flag in their

	 * &drm_bridge->ops.

	 *

	 * Returns:

	 *

	 * Either &drm_mode_status.MODE_OK or one of the failure reasons

	 * in &enum drm_mode_status.

	 */

	enum drm_mode_status

	(*hdmi_tmds_char_rate_valid)(const struct drm_bridge *bridge,

				     const struct drm_display_mode *mode,

				     unsigned long long tmds_rate);



	/**

	 * @hdmi_clear_infoframe:

	 *

	 * This callback clears the infoframes in the hardware during commit.

	 * It will be called multiple times, once for every disabled infoframe

	 * type.

	 *

	 * This callback is optional but it must be implemented by bridges that

	 * set the DRM_BRIDGE_OP_HDMI flag in their &drm_bridge->ops.

	 */

	int (*hdmi_clear_infoframe)(struct drm_bridge *bridge,

				    enum hdmi_infoframe_type type);

	/**

	 * @hdmi_write_infoframe:

	 *

	 * Program the infoframe into the hardware. It will be called multiple

	 * times, once for every updated infoframe type.

	 *

	 * This callback is optional but it must be implemented by bridges that

	 * set the DRM_BRIDGE_OP_HDMI flag in their &drm_bridge->ops.

	 */

	int (*hdmi_write_infoframe)(struct drm_bridge *bridge,

				    enum hdmi_infoframe_type type,

				    const u8 *buffer, size_t len);



	/**

	 * @debugfs_init:

	 *
@@ -705,6 +751,16 @@ enum drm_bridge_ops { 
	 * this flag shall implement the &drm_bridge_funcs->get_modes callback.

	 */

	DRM_BRIDGE_OP_MODES = BIT(3),

	/**

	 * @DRM_BRIDGE_OP_HDMI: The bridge provides HDMI connector operations,

	 * including infoframes support. Bridges that set this flag must

	 * implement the &drm_bridge_funcs->write_infoframe callback.

	 *

	 * Note: currently there can be at most one bridge in a chain that sets

	 * this bit. This is to simplify corresponding glue code in connector

	 * drivers.

	 */

	DRM_BRIDGE_OP_HDMI = BIT(4),

};



/**
@@ -773,6 +829,31 @@ struct drm_bridge { 
	 * @hpd_cb.

	 */

	void *hpd_data;



	/**

	 * @vendor: Vendor of the product to be used for the SPD InfoFrame

	 * generation. This is required if @DRM_BRIDGE_OP_HDMI is set.

	 */

	const char *vendor;



	/**

	 * @product: Name of the product to be used for the SPD InfoFrame

	 * generation. This is required if @DRM_BRIDGE_OP_HDMI is set.

	 */

	const char *product;



	/**

	 * @supported_formats: Bitmask of @hdmi_colorspace listing supported

	 * output formats. This is only relevant if @DRM_BRIDGE_OP_HDMI is set.

	 */

	unsigned int supported_formats;



	/**

	 * @max_bpc: Maximum bits per char the HDMI bridge supports. Allowed

	 * values are 8, 10 and 12. This is only relevant if

	 * @DRM_BRIDGE_OP_HDMI is set.

	 */

	unsigned int max_bpc;

};



static inline struct drm_bridge *