On Wed, Jan 17, 2018 at 6:00 PM, Daniel Thompson <daniel.thompson@xxxxxxxxxx> wrote: > On 16/01/18 10:31, 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@xxxxxxxxx> > > > To be clear I don't disagree with anthing Daniel V. said about the horribly > confused (and confusing) power states for backlight. > > Nevertheless I don't recall seeing any response (positive or negative) to > this post from v13: > https://www.spinics.net/lists/dri-devel/msg154459.html I think also adjusting the fb_blank bits in these new helpers is a reasonable thing to do. Maybe with add a huge TODO comment that this is all a bit sad ... -Daniel > Daniel. > > > >> --- >> include/linux/backlight.h | 30 ++++++++++++++++++++++++++++++ >> 1 file changed, 30 insertions(+) >> >> diff --git a/include/linux/backlight.h b/include/linux/backlight.h >> index af7003548..7b6a9a2a3 100644 >> --- a/include/linux/backlight.h >> +++ b/include/linux/backlight.h >> @@ -130,6 +130,36 @@ 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.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.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); >> > _______________________________________________ > dri-devel mailing list > dri-devel@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
