Re: [PATCH v3 2/2] led: led-class: Read max-brightness from devicetree

From: Jacek Anaszewski
Date: Mon Jul 03 2023 - 17:39:59 EST


Hi Astrid,

Thanks for the update.

On 7/3/23 15:03, Astrid Rost wrote:
Normally, the maximum brightness is determined by the hardware, and this
property is not required. This property is used to set a software limit.
It could happen that an LED is made so bright that it gets damaged or
causes damage due to restrictions in a specific system, such as mounting
conditions.
Note that this flag is mainly used for PWM-LEDs, where it is not possible
to map brightness to current. Drivers for other controllers should use
led-max-microamp.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Signed-off-by: Astrid Rost <astrid.rost@xxxxxxxx>
---
drivers/leds/led-class.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 9255bc11f99d..ce652abf9336 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -457,6 +457,10 @@ int led_classdev_register_ext(struct device *parent,
if (fwnode_property_present(init_data->fwnode,
"retain-state-shutdown"))
led_cdev->flags |= LED_RETAIN_AT_SHUTDOWN;
+
+ fwnode_property_read_u32(init_data->fwnode,
+ "max-brightness",
+ &led_cdev->max_brightness);
}
} else {
proposed_name = led_cdev->name;

For the whole set:

Acked-by: Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx>

--
Best regards,
Jacek Anaszewski