From: Alex Hung <alex.hung@xxxxxxxxxxxxx> 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@xxxxxxxxxxxxxxx> Signed-off-by: Alex Hung <alex.hung@xxxxxxxxxxxxx> [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/acpi/video_detect.c | 9 +++++++++ 1 file changed, 9 insertions(+) --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -274,6 +274,15 @@ static const struct dmi_system_id video_ 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 */ {
