[PATCH] various fbdev files: mark structs and array read-only

[firefly-linux-kernel-4.4.55.git] / drivers / video / backlight / backlight.c

diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index bd39bbd88d41e7042e7fa76bf2a35e1c3145ebbc..f439a588394ae5b0b62781211b5c46fa06d9322c 100644 (file)
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -16,14 +16,12 @@
 
 static ssize_t backlight_show_power(struct class_device *cdev, char *buf)
 {
-       int rc;
+       int rc = -ENXIO;
        struct backlight_device *bd = to_backlight_device(cdev);
 
        down(&bd->sem);
-       if (likely(bd->props && bd->props->get_power))
-               rc = sprintf(buf, "%d\n", bd->props->get_power(bd));
-       else
-               rc = -ENXIO;
+       if (likely(bd->props))
+               rc = sprintf(buf, "%d\n", bd->props->power);
        up(&bd->sem);
 
        return rc;
@@ -31,21 +29,25 @@ static ssize_t backlight_show_power(struct class_device *cdev, char *buf)
 
 static ssize_t backlight_store_power(struct class_device *cdev, const char *buf, size_t count)
 {
-       int rc, power;
+       int rc = -ENXIO;
        char *endp;
        struct backlight_device *bd = to_backlight_device(cdev);
+       int power = simple_strtoul(buf, &endp, 0);
+       size_t size = endp - buf;
 
-       power = simple_strtoul(buf, &endp, 0);
-       if (*endp && !isspace(*endp))
+       if (*endp && isspace(*endp))
+               size++;
+       if (size != count)
                return -EINVAL;
 
        down(&bd->sem);
-       if (likely(bd->props && bd->props->set_power)) {
+       if (likely(bd->props)) {
                pr_debug("backlight: set power to %d\n", power);
-               bd->props->set_power(bd, power);
+               bd->props->power = power;
+               if (likely(bd->props->update_status))
+                       bd->props->update_status(bd);
                rc = count;
-       } else
-               rc = -ENXIO;
+       }
        up(&bd->sem);
 
        return rc;
@@ -53,14 +55,12 @@ static ssize_t backlight_store_power(struct class_device *cdev, const char *buf,
 
 static ssize_t backlight_show_brightness(struct class_device *cdev, char *buf)
 {
-       int rc;
+       int rc = -ENXIO;
        struct backlight_device *bd = to_backlight_device(cdev);
 
        down(&bd->sem);
-       if (likely(bd->props && bd->props->get_brightness))
-               rc = sprintf(buf, "%d\n", bd->props->get_brightness(bd));
-       else
-               rc = -ENXIO;
+       if (likely(bd->props))
+               rc = sprintf(buf, "%d\n", bd->props->brightness);
        up(&bd->sem);
 
        return rc;
@@ -68,21 +68,30 @@ static ssize_t backlight_show_brightness(struct class_device *cdev, char *buf)
 
 static ssize_t backlight_store_brightness(struct class_device *cdev, const char *buf, size_t count)
 {
-       int rc, brightness;
+       int rc = -ENXIO;
        char *endp;
        struct backlight_device *bd = to_backlight_device(cdev);
+       int brightness = simple_strtoul(buf, &endp, 0);
+       size_t size = endp - buf;
 
-       brightness = simple_strtoul(buf, &endp, 0);
-       if (*endp && !isspace(*endp))
+       if (*endp && isspace(*endp))
+               size++;
+       if (size != count)
                return -EINVAL;
 
        down(&bd->sem);
-       if (likely(bd->props && bd->props->set_brightness)) {
-               pr_debug("backlight: set brightness to %d\n", brightness);
-               bd->props->set_brightness(bd, brightness);
-               rc = count;
-       } else
-               rc = -ENXIO;
+       if (likely(bd->props)) {
+               if (brightness > bd->props->max_brightness)
+                       rc = -EINVAL;
+               else {
+                       pr_debug("backlight: set brightness to %d\n",
+                                brightness);
+                       bd->props->brightness = brightness;
+                       if (likely(bd->props->update_status))
+                               bd->props->update_status(bd);
+                       rc = count;
+               }
+       }
        up(&bd->sem);
 
        return rc;
@@ -90,14 +99,26 @@ static ssize_t backlight_store_brightness(struct class_device *cdev, const char
 
 static ssize_t backlight_show_max_brightness(struct class_device *cdev, char *buf)
 {
-       int rc;
+       int rc = -ENXIO;
        struct backlight_device *bd = to_backlight_device(cdev);
 
        down(&bd->sem);
        if (likely(bd->props))
                rc = sprintf(buf, "%d\n", bd->props->max_brightness);
-       else
-               rc = -ENXIO;
+       up(&bd->sem);
+
+       return rc;
+}
+
+static ssize_t backlight_show_actual_brightness(struct class_device *cdev,
+                                               char *buf)
+{
+       int rc = -ENXIO;
+       struct backlight_device *bd = to_backlight_device(cdev);
+
+       down(&bd->sem);
+       if (likely(bd->props && bd->props->get_brightness))
+               rc = sprintf(buf, "%d\n", bd->props->get_brightness(bd));
        up(&bd->sem);
 
        return rc;
@@ -121,9 +142,12 @@ static struct class backlight_class = {
        .store  = _store,                                       \
 }
 
-static struct class_device_attribute bl_class_device_attributes[] = {
+static const struct class_device_attribute bl_class_device_attributes[] = {
        DECLARE_ATTR(power, 0644, backlight_show_power, backlight_store_power),
-       DECLARE_ATTR(brightness, 0644, backlight_show_brightness, backlight_store_brightness),
+       DECLARE_ATTR(brightness, 0644, backlight_show_brightness,
+                    backlight_store_brightness),
+       DECLARE_ATTR(actual_brightness, 0444, backlight_show_actual_brightness,
+                    NULL),
        DECLARE_ATTR(max_brightness, 0444, backlight_show_max_brightness, NULL),
 };
 
@@ -144,8 +168,12 @@ static int fb_notifier_callback(struct notifier_block *self,
        bd = container_of(self, struct backlight_device, fb_notif);
        down(&bd->sem);
        if (bd->props)
-               if (!bd->props->check_fb || bd->props->check_fb(evdata->info))
-                       bd->props->set_power(bd, *(int *)evdata->data);
+               if (!bd->props->check_fb ||
+                   bd->props->check_fb(evdata->info)) {
+                       bd->props->fb_blank = *(int *)evdata->data;
+                       if (likely(bd->props && bd->props->update_status))
+                               bd->props->update_status(bd);
+               }
        up(&bd->sem);
        return 0;
 }
@@ -172,7 +200,7 @@ struct backlight_device *backlight_device_register(const char *name, void *devda
 
        new_bd = kmalloc(sizeof(struct backlight_device), GFP_KERNEL);
        if (unlikely(!new_bd))
-               return ERR_PTR(ENOMEM);
+               return ERR_PTR(-ENOMEM);
 
        init_MUTEX(&new_bd->sem);
        new_bd->props = bp;
@@ -231,6 +259,12 @@ void backlight_device_unregister(struct backlight_device *bd)
                                         &bl_class_device_attributes[i]);
 
        down(&bd->sem);
+       if (likely(bd->props && bd->props->update_status)) {
+               bd->props->brightness = 0;
+               bd->props->power = 0;
+               bd->props->update_status(bd);
+       }
+
        bd->props = NULL;
        up(&bd->sem);