diff options
Diffstat (limited to 'drivers/video/backlight/gpio_backlight.c')
| -rw-r--r-- | drivers/video/backlight/gpio_backlight.c | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c index e84f3087e29f..18e053e4716c 100644 --- a/drivers/video/backlight/gpio_backlight.c +++ b/drivers/video/backlight/gpio_backlight.c @@ -59,13 +59,11 @@ static int gpio_backlight_probe_dt(struct platform_device *pdev, struct gpio_backlight *gbl) { struct device *dev = &pdev->dev; - enum gpiod_flags flags; int ret; gbl->def_value = device_property_read_bool(dev, "default-on"); - flags = gbl->def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW; - gbl->gpiod = devm_gpiod_get(dev, NULL, flags); + gbl->gpiod = devm_gpiod_get(dev, NULL, GPIOD_ASIS); if (IS_ERR(gbl->gpiod)) { ret = PTR_ERR(gbl->gpiod); @@ -79,6 +77,22 @@ static int gpio_backlight_probe_dt(struct platform_device *pdev, return 0; } +static int gpio_backlight_initial_power_state(struct gpio_backlight *gbl) +{ + struct device_node *node = gbl->dev->of_node; + + /* Not booted with device tree or no phandle link to the node */ + if (!node || !node->phandle) + return gbl->def_value ? FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN; + + /* if the enable GPIO is disabled, do not enable the backlight */ + if (gpiod_get_value_cansleep(gbl->gpiod) == 0) + return FB_BLANK_POWERDOWN; + + return FB_BLANK_UNBLANK; +} + + static int gpio_backlight_probe(struct platform_device *pdev) { struct gpio_backlight_platform_data *pdata = @@ -136,7 +150,9 @@ static int gpio_backlight_probe(struct platform_device *pdev) return PTR_ERR(bl); } - bl->props.brightness = gbl->def_value; + bl->props.power = gpio_backlight_initial_power_state(gbl); + bl->props.brightness = 1; + backlight_update_status(bl); platform_set_drvdata(pdev, bl); |