[PATCH v2 4/4] drm/msm/dp: Add driver support to utilize drm panel

[Sankeerth Billakanti <quic_sbillaka@quicinc.com>]

Add support in the DP driver to utilize the custom eDP panels
from drm/panels.

An eDP panel is always connected to the platform. So, the eDP
connector can be reported as always connected. The display mode
will be sourced from the panel. The panel mode will be set after
the link training is completed.

The eDP driver needs to register for IRQ_HPD only.
This support will be added later.

Signed-off-by: Sankeerth Billakanti <quic_sbillaka@quicinc.com>
---
 drivers/gpu/drm/msm/dp/dp_display.c |  8 ++++++
 drivers/gpu/drm/msm/dp/dp_drm.c     | 54 +++++++++++++++++++++++++++++++++----
 drivers/gpu/drm/msm/dp/dp_parser.h  |  3 +++
 3 files changed, 60 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 7cc4d21..410fda4 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -1513,6 +1513,10 @@ int msm_dp_display_enable(struct msm_dp *dp, struct drm_encoder *encoder)
 		return -EINVAL;
 	}
 
+	/* handle eDP on */
+	if (dp->connector_type == DRM_MODE_CONNECTOR_eDP)
+		dp_hpd_plug_handle(dp_display, 0);
+
 	mutex_lock(&dp_display->event_mutex);
 
 	/* stop sentinel checking */
@@ -1577,6 +1581,10 @@ int msm_dp_display_disable(struct msm_dp *dp, struct drm_encoder *encoder)
 
 	dp_display = container_of(dp, struct dp_display_private, dp_display);
 
+	/* handle edp off */
+	if (dp->connector_type == DRM_MODE_CONNECTOR_eDP)
+		dp_hpd_unplug_handle(dp_display, 0);
+
 	mutex_lock(&dp_display->event_mutex);
 
 	/* stop sentinel checking */
diff --git a/drivers/gpu/drm/msm/dp/dp_drm.c b/drivers/gpu/drm/msm/dp/dp_drm.c
index d4d360d..12fa8c1 100644
--- a/drivers/gpu/drm/msm/dp/dp_drm.c
+++ b/drivers/gpu/drm/msm/dp/dp_drm.c
@@ -39,6 +39,10 @@ static enum drm_connector_status dp_connector_detect(struct drm_connector *conn,
 
 	dp = to_dp_connector(conn)->dp_display;
 
+	/* eDP is always  connected */
+	if (dp->connector_type == DRM_MODE_CONNECTOR_eDP)
+		return connector_status_connected;
+
 	DRM_DEBUG_DP("is_connected = %s\n",
 		(dp->is_connected) ? "true" : "false");
 
@@ -123,6 +127,35 @@ static enum drm_mode_status dp_connector_mode_valid(
 	return dp_display_validate_mode(dp_disp, mode->clock);
 }
 
+static int edp_connector_get_modes(struct drm_connector *connector)
+{
+	struct msm_dp *dp;
+
+	if (!connector)
+		return 0;
+
+	dp = to_dp_connector(connector)->dp_display;
+
+	return drm_bridge_get_modes(dp->panel_bridge, connector);
+}
+
+static enum drm_mode_status edp_connector_mode_valid(
+		struct drm_connector *connector,
+		struct drm_display_mode *mode)
+{
+	struct msm_dp *dp;
+
+	if (!connector)
+		return 0;
+
+	dp = to_dp_connector(connector)->dp_display;
+
+	if (mode->clock > EDP_MAX_PIXEL_CLK_KHZ)
+		return MODE_BAD;
+
+	return MODE_OK;
+}
+
 static const struct drm_connector_funcs dp_connector_funcs = {
 	.detect = dp_connector_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
@@ -137,6 +170,12 @@ static const struct drm_connector_helper_funcs dp_connector_helper_funcs = {
 	.mode_valid = dp_connector_mode_valid,
 };
 
+static const struct drm_connector_helper_funcs edp_connector_helper_funcs = {
+	.get_modes = edp_connector_get_modes,
+	.mode_valid = edp_connector_mode_valid,
+
+};
+
 /* connector initialization */
 struct drm_connector *dp_drm_connector_init(struct msm_dp *dp_display)
 {
@@ -160,12 +199,17 @@ struct drm_connector *dp_drm_connector_init(struct msm_dp *dp_display)
 	if (ret)
 		return ERR_PTR(ret);
 
-	drm_connector_helper_add(connector, &dp_connector_helper_funcs);
+	if (dp_display->connector_type == DRM_MODE_CONNECTOR_eDP) {
+		drm_connector_helper_add(connector,
+				&edp_connector_helper_funcs);
+	} else {
+		drm_connector_helper_add(connector, &dp_connector_helper_funcs);
 
-	/*
-	 * Enable HPD to let hpd event is handled when cable is connected.
-	 */
-	connector->polled = DRM_CONNECTOR_POLL_HPD;
+		/*
+		 * Enable HPD to let hpd event is handled when cable is connected.
+		 */
+		connector->polled = DRM_CONNECTOR_POLL_HPD;
+	}
 
 	drm_connector_attach_encoder(connector, dp_display->encoder);
 
diff --git a/drivers/gpu/drm/msm/dp/dp_parser.h b/drivers/gpu/drm/msm/dp/dp_parser.h
index 3172da0..58c4f27 100644
--- a/drivers/gpu/drm/msm/dp/dp_parser.h
+++ b/drivers/gpu/drm/msm/dp/dp_parser.h
@@ -17,6 +17,9 @@
 #define DP_MAX_PIXEL_CLK_KHZ	675000
 #define DP_MAX_NUM_DP_LANES	4
 
+/* Maximum validated clock */
+#define EDP_MAX_PIXEL_CLK_KHZ	285550
+
 enum dp_pm_type {
 	DP_CORE_PM,
 	DP_CTRL_PM,
-- 
2.7.4