On Tue, 2015-11-03 at 12:08 +0100, Philipp Zabel wrote: > Hi YH, > > Am Dienstag, den 03.11.2015, 16:11 +0800 schrieb YH Huang: > > > The reasoning is that devices where there is no phandle link pointing to > > > the backlight (for example from a simple-panel node), we should keep the > > > current default behaviour (enable during probe). > > > > I have a little problem for the current default behaviour. > > Should we enable during probe? > > Here I mean enabling the backlight (at the end of the probe function), > not enabling the GPIO already when requesting it. > > > Before this patch ( http://patchwork.ozlabs.org/patch/324690/ ), > > we disable "enable-gpio" in the probe function. > > While before this patch the GPIO would be initialized in the disabled > state, the call to backlight_update_status at the end of the probe > function would still enable the backlight afterwards. Based on this, could we disable it initially and update in the backlight_update_status function? Like this, if (pb->enable_gpio) { if (phandle && gpiod_get_direction(pb->enable_gpio) == GPIOF_DIR_OUT && gpiod_get_value(pb->enable_gpio) == 1) gpiod_direction_output(pb->enable_gpio, 1); else gpiod_direction_output(pb->enable_gpio, 0); } And then update with props.brightness in backlight_update_status. I am not sure, maybe I miss something. Regards, YH Huang -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
