ACPI / video: Filter the _BCL table for duplicate brightness values

[~andy/linux] / drivers / acpi / video.c

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index b727d105046d234ae8ef2a5669e53e61b82e7123..ea9d914d937a14ca797f5e8ce9b826e918956263 100644 (file)
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -685,6 +685,7 @@ acpi_video_init_brightness(struct acpi_video_device *device)
        union acpi_object *o;
        struct acpi_video_device_brightness *br = NULL;
        int result = -EINVAL;
+       u32 value;
 
        if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
@@ -715,7 +716,12 @@ acpi_video_init_brightness(struct acpi_video_device *device)
                        printk(KERN_ERR PREFIX "Invalid data\n");
                        continue;
                }
-               br->levels[count] = (u32) o->integer.value;
+               value = (u32) o->integer.value;
+               /* Skip duplicate entries */
+               if (count > 2 && br->levels[count - 1] == value)
+                       continue;
+
+               br->levels[count] = value;
 
                if (br->levels[count] > max_level)
                        max_level = br->levels[count];