ACPI: video: use ACPI backlight for HP 635 Notebook

commit b226faab4e7890bbbccdf794e8b94276414f9058 upstream.

The default backlight interface is AMD's radeon_bl0 which does not
work on this system, so use the ACPI backlight interface on it
instead.

BugLink: https://bugs.launchpad.net/bugs/1894667
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Alex Hung <alex.hung@canonical.com>
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c
index ab1da5e6e7e3e8bc2931a0153f6de6c6d46eb9fb..86ffb4af4afcacd46fd08322ae573d9eaacb7702 100644 (file)
--- a/drivers/acpi/video_detect.c
+++ b/drivers/acpi/video_detect.c
@@ -274,6 +274,15 @@ static const struct dmi_system_id video_detect_dmi_table[] = {
                DMI_MATCH(DMI_PRODUCT_NAME, "530U4E/540U4E"),
                },
        },
+       /* https://bugs.launchpad.net/bugs/1894667 */
+       {
+        .callback = video_detect_force_video,
+        .ident = "HP 635 Notebook",
+        .matches = {
+               DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+               DMI_MATCH(DMI_PRODUCT_NAME, "HP 635 Notebook PC"),
+               },
+       },
 
        /* Non win8 machines which need native backlight nevertheless */
        {