drm/omap: Support for HDMI hot plug detection

The HPD signal can be used for detecting HDMI cable plug and unplug event
without the need for polling the status of the line.
This will speed up detecting such event because we do not need to wait for
the next poll event to notice the state change.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/gpu/drm/omapdrm/dss/omapdss.h

@@ -25,6 +25,7 @@
 #include <video/videomode.h>
 #include <linux/platform_data/omapdss.h>
 #include <uapi/drm/drm_mode.h>
+#include <drm/drm_crtc.h>
 
 #define DISPC_IRQ_FRAMEDONE		(1 << 0)
 #define DISPC_IRQ_VSYNC			(1 << 1)
@@ -403,6 +404,14 @@ struct omapdss_hdmi_ops {
 	int (*read_edid)(struct omap_dss_device *dssdev, u8 *buf, int len);
 	bool (*detect)(struct omap_dss_device *dssdev);
 
+	int (*register_hpd_cb)(struct omap_dss_device *dssdev,
+			       void (*cb)(void *cb_data,
+					  enum drm_connector_status status),
+			       void *cb_data);
+	void (*unregister_hpd_cb)(struct omap_dss_device *dssdev);
+	void (*enable_hpd)(struct omap_dss_device *dssdev);
+	void (*disable_hpd)(struct omap_dss_device *dssdev);
+
 	int (*set_hdmi_mode)(struct omap_dss_device *dssdev, bool hdmi_mode);
 	int (*set_infoframe)(struct omap_dss_device *dssdev,
 		const struct hdmi_avi_infoframe *avi);
@@ -567,6 +576,14 @@ struct omap_dss_driver {
 	int (*read_edid)(struct omap_dss_device *dssdev, u8 *buf, int len);
 	bool (*detect)(struct omap_dss_device *dssdev);
 
+	int (*register_hpd_cb)(struct omap_dss_device *dssdev,
+			       void (*cb)(void *cb_data,
+					  enum drm_connector_status status),
+			       void *cb_data);
+	void (*unregister_hpd_cb)(struct omap_dss_device *dssdev);
+	void (*enable_hpd)(struct omap_dss_device *dssdev);
+	void (*disable_hpd)(struct omap_dss_device *dssdev);
+
 	int (*set_hdmi_mode)(struct omap_dss_device *dssdev, bool hdmi_mode);
 	int (*set_hdmi_infoframe)(struct omap_dss_device *dssdev,
 		const struct hdmi_avi_infoframe *avi);