[ 19/32] ACPI / video: ignore BIOS initial backlight value for HP m4

From: Greg Kroah-Hartman
Date: Tue Jun 11 2013 - 16:33:45 EST


3.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Alex Hung <alex.hung@xxxxxxxxxxxxx>

commit fedbe9bc6fd3e14b1ffbb3dac407777ac4a3650c upstream.

On HP m4 lapops, BIOS reports minimum backlight on boot and
causes backlight to dim completely. This ignores the initial backlight
values and set to max brightness.

References: https://bugs.launchpad.net/bugs/1184501
Signed-off-by: Alex Hung <alex.hung@xxxxxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/acpi/video.c | 8 ++++++++
1 file changed, 8 insertions(+)

--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -447,6 +447,14 @@ static struct dmi_system_id video_dmi_ta
DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13 - 2000 Notebook PC"),
},
},
+ {
+ .callback = video_ignore_initial_backlight,
+ .ident = "HP Pavilion m4",
+ .matches = {
+ DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion m4 Notebook PC"),
+ },
+ },
{}
};



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/