video: mbp_nvidia_bl: Fix brightness after suspend/hibernation

index 06964af..40a6b79 100644
@@ -25,8 +25,6 @@
 #include <linux/dmi.h>
 #include <linux/io.h>
 
-static struct backlight_device *mbp_backlight_device;
-
 static struct dmi_system_id __initdata mbp_device_table[] = {
 	{
 		.ident = "3,1",

@@ -74,35 +72,96 @@ static struct backlight_ops mbp_ops = {
 	.update_status  = mbp_send_intensity,
 };
 
+static int mbp_probe(struct platform_device *pdev)
+{
+	struct backlight_device *bd;
+
+	bd = backlight_device_register("mbp_backlight", NULL, NULL, &mbp_ops);
+	if (IS_ERR(bd))
+		return PTR_ERR(bd);
+
+	bd->props.max_brightness = 15;
+	bd->props.brightness = mbp_get_intensity(bd);
+	backlight_update_status(bd);
+
+	platform_set_drvdata(pdev, bd);
+	return 0;
+}
+
+static int mbp_remove(struct platform_device *pdev)
+{
+	struct backlight_device *bd = platform_get_drvdata(pdev);
+
+	backlight_device_unregister(bd);
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int mbp_resume(struct platform_device *pdev)
+{
+	/*
+	 * Nvidia GeForce 8600M GT in MacBookPro 3,1 and MacBookPro 4,1:
+	 *   1. Resume after suspend:
+	 *      SMI still reports the last recently written value, while
+	 *      the brightness is actually at its maximum.
+	 *   2. Resume after hibernation:
+	 *      SMI reports the actual (maximum) value, but the state
+	 *      in props.brightness might be different.
+	 * -> Re-send to fix (1), but do not re-read to fix (2).
+	 */
+	struct backlight_device *bd = platform_get_drvdata(pdev);
+
+	backlight_update_status(bd);
+	return 0;
+}
+#else
+#define mbp_resume NULL
+#endif
+
+static struct platform_driver mbp_driver = {
+	.probe          = mbp_probe,
+	.remove         = mbp_remove,
+	.resume         = mbp_resume,
+	.driver         = {
+		.owner  = THIS_MODULE,
+		.name   = "mbp_nvidia_bl"
+	},
+};
+
+static struct resource mbp_iores = {
+	.start          = 0xb2,
+	.end            = 0xb3,
+	.name           = "mbp_nvidia_bl",
+	.flags          = IORESOURCE_IO
+};
+
+static struct platform_device *mbp_device;
+
 static int __init mbp_init(void)
 {
+	int ret;
+
 	if (!dmi_check_system(mbp_device_table))
 		return -ENODEV;
 
-	if (!request_region(0xb2, 2, "Macbook Pro backlight"))
-		return -ENXIO;
+	ret = platform_driver_register(&mbp_driver);
+	if (ret)
+		return ret;
 
-	mbp_backlight_device = backlight_device_register("mbp_backlight",
-							 NULL, NULL,
-							 &mbp_ops);
-	if (IS_ERR(mbp_backlight_device)) {
-		release_region(0xb2, 2);
-		return PTR_ERR(mbp_backlight_device);
+	mbp_device = platform_device_register_simple("mbp_nvidia_bl", -1,
+						     &mbp_iores, 1);
+	if (!mbp_device) {
+		platform_driver_unregister(&mbp_driver);
+		return -ENOMEM;
 	}
 
-	mbp_backlight_device->props.max_brightness = 15;
-	mbp_backlight_device->props.brightness =
-		mbp_get_intensity(mbp_backlight_device);
-	backlight_update_status(mbp_backlight_device);
-
 	return 0;
 }
 
 static void __exit mbp_exit(void)
 {
-	backlight_device_unregister(mbp_backlight_device);
-
-	release_region(0xb2, 2);
+	platform_device_unregister(mbp_device);
+	platform_driver_unregister(&mbp_driver);
 }
 
 module_init(mbp_init);

index 592d714..fc95829 100644
@@ -40,6 +40,10 @@ static int fb_notifier_callback(struct notifier_block *self,
 		if (!bd->ops->check_fb ||
 		    bd->ops->check_fb(evdata->info)) {
 			bd->props.fb_blank = *(int *)evdata->data;
+			if (bd->props.fb_blank == FB_BLANK_UNBLANK)
+				bd->props.flags &= ~BL_CORE_FBBLANK;
+			else
+				bd->props.flags |= BL_CORE_FBBLANK;
 			backlight_update_status(bd);
 		}
 	mutex_unlock(&bd->ops_lock);

@@ -167,6 +171,34 @@ static ssize_t backlight_show_actual_brightness(struct device *dev,
 
 static struct class *backlight_class;
 
+static int backlight_suspend(struct device *dev, pm_message_t state)
+{
+	struct backlight_device *bd = to_backlight_device(dev);
+
+	if (bd->ops->flags & BL_CORE_SUSPENDRESUME) {
+		mutex_lock(&bd->ops_lock);
+		bd->props.flags |= BL_CORE_SUSPENDED;
+		backlight_update_status(bd);
+		mutex_unlock(&bd->ops_lock);
+	}
+
+	return 0;
+}
+
+static int backlight_resume(struct device *dev)
+{
+	struct backlight_device *bd = to_backlight_device(dev);
+
+	if (bd->ops->flags & BL_CORE_SUSPENDRESUME) {
+		mutex_lock(&bd->ops_lock);
+		bd->props.flags &= ~BL_CORE_SUSPENDED;
+		backlight_update_status(bd);
+		mutex_unlock(&bd->ops_lock);
+	}
+
+	return 0;
+}
+
 static void bl_device_release(struct device *dev)
 {
 	struct backlight_device *bd = to_backlight_device(dev);

@@ -283,6 +315,8 @@ static int __init backlight_class_init(void)
 	}
 
 	backlight_class->dev_attrs = bl_device_attributes;
+	backlight_class->suspend = backlight_suspend;
+	backlight_class->resume = backlight_resume;
 	return 0;
 }
 

index 4d4d037..02ff4bb 100644
@@ -25,8 +25,7 @@ static struct backlight_device *corgi_backlight_device;
 static struct generic_bl_info *bl_machinfo;
 
 static unsigned long corgibl_flags;
-#define CORGIBL_SUSPENDED     0x01
-#define CORGIBL_BATTLOW       0x02
+#define CORGIBL_BATTLOW       0x01
 
 static int corgibl_send_intensity(struct backlight_device *bd)
 {

@@ -34,9 +33,9 @@ static int corgibl_send_intensity(struct backlight_device *bd)
 
 	if (bd->props.power != FB_BLANK_UNBLANK)
 		intensity = 0;
-	if (bd->props.fb_blank != FB_BLANK_UNBLANK)
+	if (bd->props.flags & BL_CORE_FBBLANK)
 		intensity = 0;
-	if (corgibl_flags & CORGIBL_SUSPENDED)
+	if (bd->props.flags & BL_CORE_SUSPENDED)
 		intensity = 0;
 	if (corgibl_flags & CORGIBL_BATTLOW)
 		intensity &= bl_machinfo->limit_mask;

@@ -51,29 +50,6 @@ static int corgibl_send_intensity(struct backlight_device *bd)
 	return 0;
 }
 
-#ifdef CONFIG_PM
-static int corgibl_suspend(struct platform_device *pdev, pm_message_t state)
-{
-	struct backlight_device *bd = platform_get_drvdata(pdev);
-
-	corgibl_flags |= CORGIBL_SUSPENDED;
-	backlight_update_status(bd);
-	return 0;
-}
-
-static int corgibl_resume(struct platform_device *pdev)
-{
-	struct backlight_device *bd = platform_get_drvdata(pdev);
-
-	corgibl_flags &= ~CORGIBL_SUSPENDED;
-	backlight_update_status(bd);
-	return 0;
-}
-#else
-#define corgibl_suspend	NULL
-#define corgibl_resume	NULL
-#endif
-
 static int corgibl_get_intensity(struct backlight_device *bd)
 {
 	return corgibl_intensity;

@@ -95,6 +71,7 @@ EXPORT_SYMBOL(corgibl_limit_intensity);
 
 
 static struct backlight_ops corgibl_ops = {
+	.flags = BL_CORE_SUSPENDRESUME,
 	.get_brightness = corgibl_get_intensity,
 	.update_status  = corgibl_send_intensity,
 };

@@ -144,8 +121,6 @@ static int corgibl_remove(struct platform_device *pdev)
 static struct platform_driver corgibl_driver = {
 	.probe		= corgibl_probe,
 	.remove		= corgibl_remove,
-	.suspend	= corgibl_suspend,
-	.resume		= corgibl_resume,
 	.driver		= {
 		.name	= "generic-bl",
 	},

index 06964af..f5bd0b4 100644
@@ -70,6 +70,7 @@ static int mbp_get_intensity(struct backlight_device *bd)
 }
 
 static struct backlight_ops mbp_ops = {
+	.flags = BL_CORE_SUSPENDRESUME,
 	.get_brightness = mbp_get_intensity,
 	.update_status  = mbp_send_intensity,
 };

index 1ee9488..516fbc7 100644
@@ -31,6 +31,10 @@ struct backlight_device;
 struct fb_info;
 
 struct backlight_ops {
+	unsigned int flags;
+
+#define BL_CORE_SUSPENDRESUME	(1 << 0)
+
 	/* Notify the backlight driver some property has changed */
 	int (*update_status)(struct backlight_device *);
 	/* Return the current backlight brightness (accounting for power,

@@ -52,6 +56,12 @@ struct backlight_properties {
 	int power;
 	/* FB Blanking active? (values as for power) */
 	int fb_blank;
+	/* Flags used to signal drivers of state changes */
+	unsigned int flags;
+
+#define BL_CORE_SUSPENDED	(1 << 0)	/* backlight is suspended */
+#define BL_CORE_FBBLANK		(1 << 1)	/* backlight is under an fb blank event */
+
 };
 
 struct backlight_device {