From: Mario Limonciello mario.limonciello@amd.com
[ Upstream commit 5aa9d943e9b6bf6e6023645cbe7ce7d5ed84baf4 ]
The ACPI video detection code has a module parameter `register_backlight_delay` which is currently configured to 8 seconds. This means that if after 8 seconds of booting no native driver has created a backlight device then the code will attempt to make an ACPI video backlight device.
This was intended as a safety mechanism with the backlight overhaul that occurred in kernel 6.1, but as it doesn't appear necesssary set it to be disabled by default.
Suggested-by: Hans de Goede hdegoede@redhat.com Signed-off-by: Mario Limonciello mario.limonciello@amd.com Reviewed-by: Hans de Goede hdegoede@redhat.com Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/acpi/acpi_video.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c index f64fdb029090..0c79f463fbfd 100644 --- a/drivers/acpi/acpi_video.c +++ b/drivers/acpi/acpi_video.c @@ -70,11 +70,7 @@ module_param(device_id_scheme, bool, 0444); static int only_lcd = -1; module_param(only_lcd, int, 0444);
-/* - * Display probing is known to take up to 5 seconds, so delay the fallback - * backlight registration by 5 seconds + 3 seconds for some extra margin. - */ -static int register_backlight_delay = 8; +static int register_backlight_delay; module_param(register_backlight_delay, int, 0444); MODULE_PARM_DESC(register_backlight_delay, "Delay in seconds before doing fallback (non GPU driver triggered) "