gma500/cdv: Add eDP support

Introduce the eDP support into the driver.

This has been reworked a bit because kernel driver proper uses encoder/connectors
while the legacy Intel driver uses the old output stuff.

It also diverges on the backlight handling. The legacy Intel driver adds a panel
abstraction based upon the i915 one. It's only really used for backlight bits
and we have a perfectly good backlight abstraction which can extend instead.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
[ported to upstream driver, redid backlight abstraction]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/gma500/psb_drv.h

@@ -28,6 +28,7 @@
 #include "gma_drm.h"
 #include "psb_reg.h"
 #include "psb_intel_drv.h"
+#include "intel_bios.h"
 #include "gtt.h"
 #include "power.h"
 #include "opregion.h"
@@ -613,6 +614,8 @@ struct drm_psb_private {
 	 */
 	struct backlight_device *backlight_device;
 	struct drm_property *backlight_property;
+	bool backlight_enabled;
+	int backlight_level;
 	uint32_t blc_adj1;
 	uint32_t blc_adj2;
 
@@ -640,6 +643,19 @@ struct drm_psb_private {
 	int mdfld_panel_id;
 
 	bool dplla_96mhz;	/* DPLL data from the VBT */
+
+	struct {
+		int rate;
+		int lanes;
+		int preemphasis;
+		int vswing;
+
+		bool initialized;
+		bool support;
+		int bpp;
+		struct edp_power_seq pps;
+	} edp;
+	uint8_t panel_type;
 };
 
 
@@ -796,6 +812,9 @@ extern int psb_fbdev_init(struct drm_device *dev);
 /* backlight.c */
 int gma_backlight_init(struct drm_device *dev);
 void gma_backlight_exit(struct drm_device *dev);
+void gma_backlight_disable(struct drm_device *dev);
+void gma_backlight_enable(struct drm_device *dev);
+void gma_backlight_set(struct drm_device *dev, int v);
 
 /* oaktrail_crtc.c */
 extern const struct drm_crtc_helper_funcs oaktrail_helper_funcs;