Hi Stephen, thanks for taking care of all these backlight simplifications - this really helps to make the code simpler and more readable. On Thu, Jun 09, 2022 at 10:54:12AM +0100, Daniel Thompson wrote: > On Wed, Jun 08, 2022 at 10:56:23PM +0200, Stephen Kitt wrote: > > Instead of checking the state of various backlight_properties fields > > against the memorised state in atmel_lcdfb_info.bl_power, > > atmel_bl_update_status() should retrieve the desired state using > > backlight_get_brightness (which takes into account the power state, > > blanking etc.). This means the explicit checks using props.fb_blank > > and props.power can be dropped. > > > > Then brightness can only be negative if the backlight is on but > > props.brightness is negative, so the test before reading the > > brightness value from the hardware can be simplified to > > (brightness < 0). > > props.brightness should always be in the interval 0..max_brightness. > > This is enforced by the main backlight code (and APIs to set the > brightness use unsigned values). Thus props.brightness could only be > negative is the driver explicitly sets a negative value as some kind of > placeholder (which this driver does not do). > > I don't think there is any need to keep this logic. Daniel is right - please drop the "if (brightness < 0)" logic. I have looked a bit on the datasheet in my attempt to do a drm version of this driver - something that I am yet to succeed and the backlight core avoid any negative values. Sam
