| Message ID | 1622390172-31368-4-git-send-email-rajeevny@codeaurora.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | drm: Support basic DPCD backlight in panel-simple and add a new panel ATNA33XC20 | expand |
Hi, On Sun, May 30, 2021 at 8:57 AM Rajeev Nandan <rajeevny@codeaurora.org> wrote: > > Some panels datasheets may specify a delay between the enable GPIO and > the regulator. Support this in panel-simple. > > Signed-off-by: Rajeev Nandan <rajeevny@codeaurora.org> > --- > > Changes in v4: > - New > > Changes in v5: > - Update description (Douglas) > - Warn if "power_to_enable" or "disable_to_power_off" is non-zero and panel->enable_gpio > is NULL (Douglas) > > drivers/gpu/drm/panel/panel-simple.c | 28 ++++++++++++++++++++++++++++ > 1 file changed, 28 insertions(+) > > diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c > index 047fad5..e3f5b7e 100644 > --- a/drivers/gpu/drm/panel/panel-simple.c > +++ b/drivers/gpu/drm/panel/panel-simple.c > @@ -133,6 +133,22 @@ struct panel_desc { > unsigned int prepare_to_enable; > > /** > + * @delay.power_to_enable: Time for the power to enable the display on. > + * > + * The time (in milliseconds) to wait after powering up the display > + * before asserting its enable pin. > + */ > + unsigned int power_to_enable; > + > + /** > + * @delay.disable_to_power_off: Time for the disable to power the display off. > + * > + * The time (in milliseconds) to wait before powering off the display > + * after deasserting its enable pin. > + */ > + unsigned int disable_to_power_off; > + > + /** > * @delay.enable: Time for the panel to display a valid frame. > * > * The time (in milliseconds) that it takes for the panel to > @@ -347,6 +363,10 @@ static int panel_simple_suspend(struct device *dev) > struct panel_simple *p = dev_get_drvdata(dev); > > gpiod_set_value_cansleep(p->enable_gpio, 0); > + > + if (p->desc->delay.disable_to_power_off) > + msleep(p->desc->delay.disable_to_power_off); > + > regulator_disable(p->supply); > p->unprepared_time = ktime_get(); > > @@ -407,6 +427,9 @@ static int panel_simple_prepare_once(struct panel_simple *p) > return err; > } > > + if (p->desc->delay.power_to_enable) > + msleep(p->desc->delay.power_to_enable); > + > gpiod_set_value_cansleep(p->enable_gpio, 1); > > delay = p->desc->delay.prepare; > @@ -782,6 +805,11 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc, > break; > } > > + if (!panel->enable_gpio && desc->delay.disable_to_power_off) > + dev_warn(dev, "Specify enable_gpio when using disable_to_power_off delay\n"); > + if (!panel->enable_gpio && desc->delay.power_to_enable) > + dev_warn(dev, "Specify enable_gpio when using power_to_enable delay\n"); Last nit is that the warning messages could be a little confusing to someone reading the logs. I guess the target audience of the error message is probably someone doing bringup. That person specified a panel in their device tree and maybe isn't even aware that they're using "disable_to_power_off" or "power_to_enable". Maybe wording instead: Need a delay after disabling panel GPIO, but a GPIO wasn't provided. Need a delay after enabling panel GPIO, but a GPIO wasn't provided. That's definitely getting into nittiness, though and I wouldn't be upset if the patch landed with the existing messages. Thus, with or without the change to the error message: Reviewed-by: Douglas Anderson <dianders@chromium.org>
diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c index 047fad5..e3f5b7e 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -133,6 +133,22 @@ struct panel_desc { unsigned int prepare_to_enable; /** + * @delay.power_to_enable: Time for the power to enable the display on. + * + * The time (in milliseconds) to wait after powering up the display + * before asserting its enable pin. + */ + unsigned int power_to_enable; + + /** + * @delay.disable_to_power_off: Time for the disable to power the display off. + * + * The time (in milliseconds) to wait before powering off the display + * after deasserting its enable pin. + */ + unsigned int disable_to_power_off; + + /** * @delay.enable: Time for the panel to display a valid frame. * * The time (in milliseconds) that it takes for the panel to @@ -347,6 +363,10 @@ static int panel_simple_suspend(struct device *dev) struct panel_simple *p = dev_get_drvdata(dev); gpiod_set_value_cansleep(p->enable_gpio, 0); + + if (p->desc->delay.disable_to_power_off) + msleep(p->desc->delay.disable_to_power_off); + regulator_disable(p->supply); p->unprepared_time = ktime_get(); @@ -407,6 +427,9 @@ static int panel_simple_prepare_once(struct panel_simple *p) return err; } + if (p->desc->delay.power_to_enable) + msleep(p->desc->delay.power_to_enable); + gpiod_set_value_cansleep(p->enable_gpio, 1); delay = p->desc->delay.prepare; @@ -782,6 +805,11 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc, break; } + if (!panel->enable_gpio && desc->delay.disable_to_power_off) + dev_warn(dev, "Specify enable_gpio when using disable_to_power_off delay\n"); + if (!panel->enable_gpio && desc->delay.power_to_enable) + dev_warn(dev, "Specify enable_gpio when using power_to_enable delay\n"); + dev_set_drvdata(dev, panel); /*
Some panels datasheets may specify a delay between the enable GPIO and the regulator. Support this in panel-simple. Signed-off-by: Rajeev Nandan <rajeevny@codeaurora.org> --- Changes in v4: - New Changes in v5: - Update description (Douglas) - Warn if "power_to_enable" or "disable_to_power_off" is non-zero and panel->enable_gpio is NULL (Douglas) drivers/gpu/drm/panel/panel-simple.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+)