On Tue, Nov 02, 2021 at 11:19:42AM +0000, Daniel Thompson wrote: > On Tue, Nov 02, 2021 at 10:04:55AM +0000, Corentin LABBE wrote: > > From: Jean-Jacques Hiblot <jjhiblot@xxxxxx> > > > > This patch adds support for an "enable GPIO". > > Before taking this kind of change is there a good reason why backlight > should manage the GPIO? I thought that the LED subsystem was a sub > system for LEDs (not LED controllers). In other words if you direct > that the LED be lit up then isn't it the LED driver's job to manage > the GPIO and ensure that it lights up? Sorry... I should have paid more attention to my sense of déjà vu with this patch. This approach was discussed and rejected when we first introduced the led_bl driver: https://lore.kernel.org/linux-leds/20190705100851.zn2jkipj4fxq5we6@devuan/ Daniel. > > Signed-off-by: Jean-Jacques Hiblot <jjhiblot@xxxxxx> > > Signed-off-by: Corentin LABBE <clabbe@xxxxxxxxxxxx> > > --- > > drivers/video/backlight/led_bl.c | 13 +++++++++++++ > > 1 file changed, 13 insertions(+) > > > > diff --git a/drivers/video/backlight/led_bl.c b/drivers/video/backlight/led_bl.c > > index f54d256e2d54..ebd7acc32980 100644 > > --- a/drivers/video/backlight/led_bl.c > > +++ b/drivers/video/backlight/led_bl.c > > @@ -8,6 +8,7 @@ > > > > #include <linux/backlight.h> > > #include <linux/leds.h> > > +#include <linux/gpio.h> > > #include <linux/module.h> > > #include <linux/platform_device.h> > > > > @@ -15,6 +16,7 @@ struct led_bl_data { > > struct device *dev; > > struct backlight_device *bl_dev; > > struct led_classdev **leds; > > + struct gpio_desc *enable_gpio; > > bool enabled; > > int nb_leds; > > unsigned int *levels; > > @@ -35,6 +37,9 @@ static void led_bl_set_brightness(struct led_bl_data *priv, int level) > > for (i = 0; i < priv->nb_leds; i++) > > led_set_brightness(priv->leds[i], bkl_brightness); > > > > + if (!priv->enabled) > > + gpiod_set_value_cansleep(priv->enable_gpio, 1); > > + > > priv->enabled = true; > > } > > > > @@ -48,6 +53,9 @@ static void led_bl_power_off(struct led_bl_data *priv) > > for (i = 0; i < priv->nb_leds; i++) > > led_set_brightness(priv->leds[i], LED_OFF); > > > > + if (priv->enabled) > > + gpiod_set_value_cansleep(priv->enable_gpio, 0); > > + > > priv->enabled = false; > > } > > > > @@ -209,6 +217,11 @@ static int led_bl_probe(struct platform_device *pdev) > > return PTR_ERR(priv->bl_dev); > > } > > > > + priv->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable", > > + GPIOD_OUT_LOW); > > + if (IS_ERR(priv->enable_gpio)) > > + return PTR_ERR(priv->enable_gpio); > > + > > for (i = 0; i < priv->nb_leds; i++) > > led_sysfs_disable(priv->leds[i]); > > > > -- > > 2.25.1 > >
