msm: mdss: Add support for boot LED indication

By turning on the blue LED we get a notification that the boot-
process has started. The blue LED will be turned-on in
bootloader and be turned off when HLOS display takes over.

Change-Id: Ia8f97a507a5deda9d692f0a8b53488a684f5efd2
Signed-off-by: Shimrit Malichi <smalichi@codeaurora.org>
(cherry picked from commit f6e38df1b908fdc77bab9c843cb24efb5ce8ee2f)
[veeras@codeaurora.org: Resolve merge conflict in mdss_fb.h,
mdss-mdp.txt]
Signed-off-by: Veera Sundaram Sankaran <veeras@codeaurora.org>

Documentation/devicetree/bindings/fb/mdss-mdp.txt

@@ -502,6 +502,10 @@ Subnode properties:
 - qcom,mdss-idle-power-collapse-enabled: Boolean property that enables support
 					for mdss power collapse in idle
 					screen use cases with smart panels.
+- qcom,boot-indication-enabled: Boolean property that enables turning on the blue
+				LED for notifying that the device is in boot
+				process.
+
 - qcom,mdss-pp-offets: A node that lists the offsets of post processing blocks
 		       from base module.
 		       -- qcom,mdss-mdss-sspp-igc-lut-off: This 32 bit value provides the

drivers/video/fbdev/msm/mdss_fb.c

@@ -27,7 +27,6 @@
 #include <linux/init.h>
 #include <linux/ioport.h>
 #include <linux/kernel.h>
-#include <linux/leds.h>
 #include <linux/memory.h>
 #include <linux/mm.h>
 #include <linux/module.h>
@@ -239,6 +238,11 @@ static void mdss_fb_set_bl_brightness(struct led_classdev *led_cdev,
 	struct msm_fb_data_type *mfd = dev_get_drvdata(led_cdev->dev->parent);
 	int bl_lvl;
 
+	if (mfd->boot_notification_led) {
+		led_trigger_event(mfd->boot_notification_led, 0);
+		mfd->boot_notification_led = NULL;
+	}
+
 	if (value > mfd->panel_info->brightness_max)
 		value = mfd->panel_info->brightness_max;
 
@@ -758,6 +762,15 @@ static int mdss_fb_probe(struct platform_device *pdev)
 		mfd->split_mode = MDP_DUAL_LM_DUAL_DISPLAY;
 
 	mfd->mdp = *mdp_instance;
+
+	rc = of_property_read_bool(pdev->dev.of_node,
+		"qcom,boot-indication-enabled");
+
+	if (rc) {
+		led_trigger_register_simple("boot-indication",
+			&(mfd->boot_notification_led));
+	}
+
 	INIT_LIST_HEAD(&mfd->proc_list);
 
 	mutex_init(&mfd->bl_lock);

drivers/video/fbdev/msm/mdss_fb.h

@@ -19,6 +19,7 @@
 #include <linux/msm_mdp_ext.h>
 #include <linux/types.h>
 #include <linux/notifier.h>
+#include <linux/leds.h>
 
 #include "mdss_panel.h"
 #include "mdss_mdp_splash_logo.h"
@@ -309,6 +310,7 @@ struct msm_fb_data_type {
 	u32 thermal_level;
 
 	int fb_mmap_type;
+	struct led_trigger *boot_notification_led;
 };
 
 static inline void mdss_fb_update_notify_update(struct msm_fb_data_type *mfd)