Re: [PATCH 10/10] leds: multicolor: Adjust maximum subled intensity during initialization

[Armin Wolf <W_Armin@gmx.de>]

Am 19.10.26 um 13:54 schrieb Rong Zhang:

> Hi Armin,
>
> Nice cleanup!
>
> On Sun, 2026-10-18 at 15:46 +0200, Armin Wolf wrote:
>> The maximum brightness of a LED device is fixed after having called
>> led_classdev_init(), so performing the adjustment during runtime is
>> no longer necessary.
>>
>> Signed-off-by: Armin Wolf <W_Armin@gmx.de>
>> ---
>>   drivers/leds/led-class-multicolor.c | 40 ++++++++++++-----------------
>>   1 file changed, 16 insertions(+), 24 deletions(-)
>>
>> diff --git a/drivers/leds/led-class-multicolor.c b/drivers/leds/led-class-multicolor.c
>> index 9b8c37f7bdf4..875c615c33fc 100644
>> --- a/drivers/leds/led-class-multicolor.c
>> +++ b/drivers/leds/led-class-multicolor.c
>> @@ -14,24 +14,6 @@
>>   #include <linux/uaccess.h>
>>   #include "leds.h"
>>   
>> -static unsigned int led_mc_get_max_intensity(struct led_classdev_mc *mcled_cdev, size_t index)
>> -{
>> -	unsigned int max_intensity;
>> -
>> -	/*
>> -	 * The maximum global brightness value might still be changed by
>> -	 * led_classdev_register_ext() using devicetree properties. This
>> -	 * prevents us from changing subled_info[X].max_intensity when
>> -	 * registering a multicolor LED class device, so we have to do
>> -	 * this during runtime.
>> -	 */
>> -	max_intensity = mcled_cdev->subled_info[index].max_intensity;
>> -	if (max_intensity)
>> -		return max_intensity;
>> -
>> -	return mcled_cdev->led_cdev.max_brightness;
>> -}
>> -
>>   int led_mc_calc_color_components(struct led_classdev_mc *mcled_cdev,
>>   				 enum led_brightness brightness)
>>   {
>> @@ -53,12 +35,10 @@ static ssize_t multi_max_intensity_show(struct device *dev,
>>   {
>>   	struct led_classdev *led_cdev = dev_get_drvdata(dev);
>>   	struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev);
>> -	unsigned int max_intensity;
>>   	int len = 0;
>>   
>> -	for (int i = 0; i < mcled_cdev->num_colors; i++) {
>> -		max_intensity = led_mc_get_max_intensity(mcled_cdev, i);
>> -		len += sysfs_emit_at(buf, len, "%u", max_intensity);
>> +	for (unsigned int i = 0; i < mcled_cdev->num_colors; i++) {
>> +		len += sysfs_emit_at(buf, len, "%u", mcled_cdev->subled_info[i].max_intensity);
>>   		if (i < mcled_cdev->num_colors - 1)
>>   			len += sprintf(buf + len, " ");
>>   	}
>> @@ -98,8 +78,8 @@ static ssize_t multi_intensity_store(struct device *dev,
>>   		goto err_out;
>>   	}
>>   
>> -	for (int i = 0; i < mcled_cdev->num_colors; i++) {
>> -		max_intensity = led_mc_get_max_intensity(mcled_cdev, i);
>> +	for (unsigned int i = 0; i < mcled_cdev->num_colors; i++) {
>> +		max_intensity = mcled_cdev->subled_info[i].max_intensity;
>>   		mcled_cdev->subled_info[i].intensity = min(intensity_value[i], max_intensity);
>>   	}
>>   
>> @@ -187,6 +167,18 @@ int led_classdev_multicolor_register_ext(struct device *parent,
>>   	if (ret < 0)
>>   		return ret;
>>   
>> +	/*
>> +	 * The maximum global brightness value might still be changed by
> s/still be/have been/ ?
>
> Thanks,
> Rong

Good catch, will be fixed in v2.

Thanks,
Armin Wolf

>> +	 * led_classdev_init() using devicetree properties. Because of this
>> +	 * we can only adjust subled_info[X].max_intensity after said function
>> +	 * was called.
>> +	 */
>> +	for (unsigned int i = 0; i < mcled_cdev->num_colors; i++)
>> +	{
>> +		if (!mcled_cdev->subled_info[i].max_intensity)
>> +			mcled_cdev->subled_info[i].max_intensity = led_cdev->max_brightness;
>> +	}
>> +
>>   	led_cdev->dev->type = &led_multicolor_device_type;
>>   	ret = led_classdev_add(led_cdev);
>>   	if (ret < 0)