1 files changed, 141 insertions, 6 deletions

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index b727d105046d..b6ba88ed31ae 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -81,11 +81,12 @@ static bool allow_duplicates;
 module_param(allow_duplicates, bool, 0644);
 
 /*
- * For Windows 8 systems: if set ture and the GPU driver has
- * registered a backlight interface, skip registering ACPI video's.
+ * For Windows 8 systems: used to decide if video module
+ * should skip registering backlight interface of its own.
  */
-static bool use_native_backlight = false;
-module_param(use_native_backlight, bool, 0644);
+static int use_native_backlight_param = -1;
+module_param_named(use_native_backlight, use_native_backlight_param, int, 0444);
+static bool use_native_backlight_dmi = false;
 
 static int register_count;
 static struct mutex video_list_lock;
@@ -231,9 +232,17 @@ static int acpi_video_get_next_level(struct acpi_video_device *device,
 static int acpi_video_switch_brightness(struct acpi_video_device *device,
                                          int event);
 
+static bool acpi_video_use_native_backlight(void)
+{
+        if (use_native_backlight_param != -1)
+                return use_native_backlight_param;
+        else
+                return use_native_backlight_dmi;
+}
+
 static bool acpi_video_verify_backlight_support(void)
 {
-        if (acpi_osi_is_win8() && use_native_backlight &&
+        if (acpi_osi_is_win8() && acpi_video_use_native_backlight() &&
             backlight_device_registered(BACKLIGHT_RAW))
                 return false;
         return acpi_video_backlight_support();
@@ -398,6 +407,12 @@ static int __init video_set_bqc_offset(const struct dmi_system_id *d)
         return 0;
 }
 
+static int __init video_set_use_native_backlight(const struct dmi_system_id *d)
+{
+        use_native_backlight_dmi = true;
+        return 0;
+}
+
 static struct dmi_system_id video_dmi_table[] __initdata = {
         /*
          * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
@@ -442,6 +457,120 @@ static struct dmi_system_id video_dmi_table[] __initdata = {
                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
                 },
         },
+        {
+         .callback = video_set_use_native_backlight,
+         .ident = "ThinkPad T430s",
+         .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+                DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T430s"),
+                },
+        },
+        {
+         .callback = video_set_use_native_backlight,
+         .ident = "ThinkPad X230",
+         .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+                DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X230"),
+                },
+        },
+        {
+        .callback = video_set_use_native_backlight,
+        .ident = "ThinkPad X1 Carbon",
+        .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+                DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X1 Carbon"),
+                },
+        },
+        {
+         .callback = video_set_use_native_backlight,
+         .ident = "Lenovo Yoga 13",
+         .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+                DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Yoga 13"),
+                },
+        },
+        {
+         .callback = video_set_use_native_backlight,
+         .ident = "Dell Inspiron 7520",
+         .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+                DMI_MATCH(DMI_PRODUCT_VERSION, "Inspiron 7520"),
+                },
+        },
+        {
+         .callback = video_set_use_native_backlight,
+         .ident = "Acer Aspire 5733Z",
+         .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+                DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5733Z"),
+                },
+        },
+        {
+         .callback = video_set_use_native_backlight,
+         .ident = "Acer Aspire V5-431",
+         .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+                DMI_MATCH(DMI_PRODUCT_NAME, "Aspire V5-431"),
+                },
+        },
+        {
+        .callback = video_set_use_native_backlight,
+        .ident = "HP ProBook 4340s",
+        .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+                DMI_MATCH(DMI_PRODUCT_VERSION, "HP ProBook 4340s"),
+                },
+        },
+        {
+        .callback = video_set_use_native_backlight,
+        .ident = "HP ProBook 2013 models",
+        .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+                DMI_MATCH(DMI_PRODUCT_NAME, "HP ProBook "),
+                DMI_MATCH(DMI_PRODUCT_NAME, " G1"),
+                },
+        },
+        {
+        .callback = video_set_use_native_backlight,
+        .ident = "HP EliteBook 2013 models",
+        .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+                DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook "),
+                DMI_MATCH(DMI_PRODUCT_NAME, " G1"),
+                },
+        },
+        {
+        .callback = video_set_use_native_backlight,
+        .ident = "HP ZBook 14",
+        .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+                DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 14"),
+                },
+        },
+        {
+        .callback = video_set_use_native_backlight,
+        .ident = "HP ZBook 15",
+        .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+                DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 15"),
+                },
+        },
+        {
+        .callback = video_set_use_native_backlight,
+        .ident = "HP ZBook 17",
+        .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+                DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 17"),
+                },
+        },
+        {
+        .callback = video_set_use_native_backlight,
+        .ident = "HP EliteBook 8780w",
+        .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+                DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook 8780w"),
+                },
+        },
         {}
 };
 
@@ -685,6 +814,7 @@ 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 +845,12 @@ 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];