6.15-stable review patch. If anyone has any objections, please let me know.
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From: Yao Zi ziyao@disroot.org
commit 1205088fd0393bd9eae96b62bf1e4b9eb1b73edf upstream.
Previously during driver probe, 1 is unconditionally taken as current brightness value and set to props.brightness, which will be considered as the brightness before suspend and restored to EC on resume. Since a brightness value of 1 almost never matches EC's state on coldboot (my laptop's EC defaults to 80), this causes surprising changes of screen brightness on the first time of resume after coldboot.
Let's get brightness from EC and take it as the current brightness on probe of the laptop driver to avoid the surprising behavior. Tested on TongFang L860-T2 Loongson-3A5000 laptop.
Cc: stable@vger.kernel.org Fixes: 6246ed09111f ("LoongArch: Add ACPI-based generic laptop driver") Signed-off-by: Yao Zi ziyao@disroot.org Signed-off-by: Huacai Chen chenhuacai@loongson.cn Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/platform/loongarch/loongson-laptop.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/platform/loongarch/loongson-laptop.c +++ b/drivers/platform/loongarch/loongson-laptop.c @@ -392,8 +392,8 @@ static int laptop_backlight_register(voi if (!acpi_evalf(hotkey_handle, &status, "ECLL", "d")) return -EIO;
- props.brightness = 1; props.max_brightness = status; + props.brightness = ec_get_brightness(); props.type = BACKLIGHT_PLATFORM;
backlight_device_register("loongson_laptop",