Commit 9aa92468 authored by Dmitry Baryshkov's avatar Dmitry Baryshkov
Browse files

drm/msm/dp: support attaching bridges to the DP encoder 



Currently DP driver will allocate panel bridge for eDP panels. This
supports only the following topology:

- eDP encoder ⇒ eDP panel (wrapped using panel-bridge)

Simplify this code to just check if there is any next bridge in the
chain (be it a panel bridge or regular bridge). Rename panel_bridge
field to next_bridge accordingly.

This allows one to use e.g. one of the following display topologies:

- eDP encoder ⇒ ptn3460 ⇒ fixed LVDS panel
- eDP encoder ⇒ ptn3460 ⇒ LVDS connector with EDID lines for panel autodetect
- eDP encoder ⇒ ptn3460 ⇒ THC63LVD1024 ⇒ DPI panel.
- eDP encoder ⇒ LT8912 ⇒ DSI panel

Signed-off-by: default avatarDmitry Baryshkov <dmitry.baryshkov@linaro.org>
Tested-by: default avatarKuogee Hsieh <quic_khsieh@quicinc.com>
Reviewed-by: default avatarStephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20220211224006.1797846-3-dmitry.baryshkov@linaro.org


Signed-off-by: default avatarDmitry Baryshkov <dmitry.baryshkov@linaro.org>
parent 4d793a02

drivers/gpu/drm/msm/dp/dp_display.c

+1 −1
Original line number Diff line number Diff line
@@ -266,7 +266,7 @@ static int dp_display_bind(struct device *dev, struct device *master, 
		goto end;

	}



	dp->dp_display.panel_bridge = dp->parser->panel_bridge;

	dp->dp_display.next_bridge = dp->parser->next_bridge;



	dp->aux->drm_dev = drm;

	rc = dp_aux_register(dp->aux);

drivers/gpu/drm/msm/dp/dp_display.h

+1 −1
Original line number Diff line number Diff line
@@ -16,7 +16,7 @@ struct msm_dp { 
	struct drm_bridge *bridge;

	struct drm_connector *connector;

	struct drm_encoder *encoder;

	struct drm_bridge *panel_bridge;

	struct drm_bridge *next_bridge;

	bool is_connected;

	bool audio_enabled;

	bool power_on;

drivers/gpu/drm/msm/dp/dp_drm.c

+2 −2
Original line number Diff line number Diff line
@@ -236,9 +236,9 @@ struct drm_bridge *msm_dp_bridge_init(struct msm_dp *dp_display, struct drm_devi 
		return ERR_PTR(rc);

	}



	if (dp_display->panel_bridge) {

	if (dp_display->next_bridge) {

		rc = drm_bridge_attach(dp_display->encoder,

					dp_display->panel_bridge, bridge,

					dp_display->next_bridge, bridge,

					DRM_BRIDGE_ATTACH_NO_CONNECTOR);

		if (rc < 0) {

			DRM_ERROR("failed to attach panel bridge: %d\n", rc);

drivers/gpu/drm/msm/dp/dp_parser.c

+16 −15
Original line number Diff line number Diff line
@@ -265,23 +265,16 @@ static int dp_parser_clock(struct dp_parser *parser) 
	return 0;

}



static int dp_parser_find_panel(struct dp_parser *parser)

static int dp_parser_find_next_bridge(struct dp_parser *parser)

{

	struct device *dev = &parser->pdev->dev;

	struct drm_panel *panel;

	int rc;

	struct drm_bridge *bridge;



	rc = drm_of_find_panel_or_bridge(dev->of_node, 1, 0, &panel, NULL);

	if (rc) {

		DRM_ERROR("failed to acquire DRM panel: %d\n", rc);

		return rc;

	}

	bridge = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0);

	if (IS_ERR(bridge))

		return PTR_ERR(bridge);



	parser->panel_bridge = devm_drm_panel_bridge_add(dev, panel);

	if (IS_ERR(parser->panel_bridge)) {

		DRM_ERROR("failed to create panel bridge\n");

		return PTR_ERR(parser->panel_bridge);

	}

	parser->next_bridge = bridge;



	return 0;

}
@@ -307,11 +300,19 @@ static int dp_parser_parse(struct dp_parser *parser, int connector_type) 
	if (rc)

		return rc;



	/*

	 * Currently we support external bridges only for eDP connectors.

	 *

	 * No external bridges are expected for the DisplayPort connector,

	 * it is physically present in a form of a DP or USB-C connector.

	 */

	if (connector_type == DRM_MODE_CONNECTOR_eDP) {

		rc = dp_parser_find_panel(parser);

		if (rc)

		rc = dp_parser_find_next_bridge(parser);

		if (rc) {

			DRM_ERROR("DP: failed to find next bridge\n");

			return rc;

		}

	}



	/* Map the corresponding regulator information according to

	 * version. Currently, since we only have one supported platform,

drivers/gpu/drm/msm/dp/dp_parser.h

+1 −1
Original line number Diff line number Diff line
@@ -123,7 +123,7 @@ struct dp_parser { 
	struct dp_display_data disp_data;

	const struct dp_regulator_cfg *regulator_cfg;

	u32 max_dp_lanes;

	struct drm_bridge *panel_bridge;

	struct drm_bridge *next_bridge;



	int (*parse)(struct dp_parser *parser, int connector_type);

};