[PATCH v2 2/2] backlight: gpio_backlight: add new property default-brightness-level

[Alexandru Ardelean]

From: Yannick Fertre <yannick.fertre at foss.st.com>

Add new property to set a brightness by default at probe.

Reviewed-by: Daniel Thompson <daniel.thompson at linaro.org>
Signed-off-by: Yannick Fertre <yannick.fertre at foss.st.com>
Signed-off-by: Alexandru Ardelean <alex at shruggie.ro>
---

Link to original patch:
  https://github.com/STMicroelectronics/linux/commit/c4067d7bd883c6fa14ffd49892c4ce663cdafe98

Changelog v1 -> v2:
* https://lore.kernel.org/dri-devel/20230519200520.10657-1-alex@shruggie.ro/
* removed 'Reviewed-by: Philippe CORNU <philippe.cornu at foss.st.com>' as
  requested
* patch is now second patch of 2 (was first in series)
* added 'Reviewed-by: Daniel Thompson <daniel.thompson at linaro.org>'

 drivers/video/backlight/gpio_backlight.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
index 6f78d928f054..d3fa3a8bef4d 100644
--- a/drivers/video/backlight/gpio_backlight.c
+++ b/drivers/video/backlight/gpio_backlight.c
@@ -53,6 +53,7 @@ static int gpio_backlight_probe(struct platform_device *pdev)
 	struct backlight_device *bl;
 	struct gpio_backlight *gbl;
 	int ret, init_brightness, def_value;
+	u32 value;
 
 	gbl = devm_kzalloc(dev, sizeof(*gbl), GFP_KERNEL);
 	if (gbl == NULL)
@@ -93,7 +94,11 @@ static int gpio_backlight_probe(struct platform_device *pdev)
 	else
 		bl->props.power = FB_BLANK_UNBLANK;
 
-	bl->props.brightness = 1;
+	ret = device_property_read_u32(dev, "default-brightness-level", &value);
+	if (!ret && value <= props.max_brightness)
+		bl->props.brightness = value;
+	else
+		bl->props.brightness = 1;
 
 	init_brightness = backlight_get_brightness(bl);
 	ret = gpiod_direction_output(gbl->gpiod, init_brightness);
-- 
2.40.1