Re: [PATCH v2] platform/x86: ideapad-laptop: Set max_brightness before using it

[Ilpo Järvinen]

On Tue, 14 Nov 2023, Stuart Hayhurst wrote:

> max_brightness is used in ideapad_kbd_bl_brightness_get() before it's set,
> causing ideapad_kbd_bl_brightness_get() to return -EINVAL sometimes
> 
> Fixes: ecaa1867b524 ("platform/x86: ideapad-laptop: Add support for keyboard backlights using KBLC ACPI symbol")
> Signed-off-by: Stuart Hayhurst <stuart.a.hayhurst@xxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> ---
> 
> Sorry if I messed up the stable cc bit, I have no idea how that process works

It looks fine now, thank you (except for the . missing at the end of the 
sentence but I can fix that when I'll later apply the patch).

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>

-- 
 i.

> v1 -> v2:
>  - Fix commit message
>  - Add missing tags
> 
> ---
>  drivers/platform/x86/ideapad-laptop.c | 11 +++++------
>  1 file changed, 5 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/platform/x86/ideapad-laptop.c b/drivers/platform/x86/ideapad-laptop.c
> index ac037540acfc..88eefccb6ed2 100644
> --- a/drivers/platform/x86/ideapad-laptop.c
> +++ b/drivers/platform/x86/ideapad-laptop.c
> @@ -1425,18 +1425,17 @@ static int ideapad_kbd_bl_init(struct ideapad_private *priv)
>  	if (WARN_ON(priv->kbd_bl.initialized))
>  		return -EEXIST;
>  
> -	brightness = ideapad_kbd_bl_brightness_get(priv);
> -	if (brightness < 0)
> -		return brightness;
> -
> -	priv->kbd_bl.last_brightness = brightness;
> -
>  	if (ideapad_kbd_bl_check_tristate(priv->kbd_bl.type)) {
>  		priv->kbd_bl.led.max_brightness = 2;
>  	} else {
>  		priv->kbd_bl.led.max_brightness = 1;
>  	}
>  
> +	brightness = ideapad_kbd_bl_brightness_get(priv);
> +	if (brightness < 0)
> +		return brightness;
> +
> +	priv->kbd_bl.last_brightness = brightness;
>  	priv->kbd_bl.led.name                    = "platform::" LED_FUNCTION_KBD_BACKLIGHT;
>  	priv->kbd_bl.led.brightness_get          = ideapad_kbd_bl_led_cdev_brightness_get;
>  	priv->kbd_bl.led.brightness_set_blocking = ideapad_kbd_bl_led_cdev_brightness_set;
>