Re: [PATCH v17 01/10] video: backlight: Add helpers to enable and disable backlight

[Daniel Thompson <daniel.thompson@linaro.org>]

On Fri, Jan 19, 2018 at 10:39:16AM +0000, Meghana Madhyastha wrote:
> Add helper functions backlight_enable and backlight_disable to
> enable/disable a backlight device. These helper functions can
> then be used by different drm and tinydrm drivers to avoid
> repetition of code and also to enforce a uniform and consistent
> way to enable/disable a backlight device.
> 
> Signed-off-by: Meghana Madhyastha <meghana.madhyastha@gmail.com>

Acked-by: Daniel Thompson <daniel.thompson@linaro.org>

BTW Lee J. looks PRs and merges for the backlight tree, I'll leave it 
to Lee and whoevers-DRM-tree-this-would-naturally-land-in to decide the 
merge path.


Daniel.

> ---
> changes in v17:
> -set fb_blank along with clearing the BL_CORE_FBBLANK bit
> 
>  include/linux/backlight.h | 32 ++++++++++++++++++++++++++++++++
>  1 file changed, 32 insertions(+)
> 
> diff --git a/include/linux/backlight.h b/include/linux/backlight.h
> index af7003548..ace825e2c 100644
> --- a/include/linux/backlight.h
> +++ b/include/linux/backlight.h
> @@ -130,6 +130,38 @@ static inline int backlight_update_status(struct backlight_device *bd)
>  	return ret;
>  }
>  
> +/**
> + * backlight_enable - Enable backlight
> + * @bd: the backlight device to enable
> + */
> +static inline int backlight_enable(struct backlight_device *bd)
> +{
> +	if (!bd)
> +		return 0;
> +
> +	bd->props.power = FB_BLANK_UNBLANK;
> +	bd->props.fb_blank = FB_BLANK_UNBLANK;
> +	bd->props.state &= ~BL_CORE_FBBLANK;
> +
> +	return backlight_update_status(bd);
> +}
> +
> +/**
> + * backlight_disable - Disable backlight
> + * @bd: the backlight device to disable
> + */
> +static inline int backlight_disable(struct backlight_device *bd)
> +{
> +	if (!bd)
> +		return 0;
> +
> +	bd->props.power = FB_BLANK_POWERDOWN;
> +	bd->props.fb_blank = FB_BLANK_POWERDOWN;
> +	bd->props.state |= BL_CORE_FBBLANK;
> +
> +	return backlight_update_status(bd);
> +}
> +
>  extern struct backlight_device *backlight_device_register(const char *name,
>  	struct device *dev, void *devdata, const struct backlight_ops *ops,
>  	const struct backlight_properties *props);
> -- 
> 2.11.0
>