[PATCH v1 3/4] leds: pwm-multicolor: Support active-low LEDs

From: Emil Renner Berthing
Date: Tue Jul 05 2022 - 17:02:10 EST


Add support for LEDs wired up to light when the PWM output is low, just
like the regular PWM LEDs.

Signed-off-by: Emil Renner Berthing <emil.renner.berthing@xxxxxxxxxxxxx>
---
drivers/leds/rgb/leds-pwm-multicolor.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/leds/rgb/leds-pwm-multicolor.c b/drivers/leds/rgb/leds-pwm-multicolor.c
index eb67b89d28e9..da9d2218ae18 100644
--- a/drivers/leds/rgb/leds-pwm-multicolor.c
+++ b/drivers/leds/rgb/leds-pwm-multicolor.c
@@ -19,6 +19,7 @@
struct pwm_led {
struct pwm_device *pwm;
struct pwm_state state;
+ bool active_low;
};

struct pwm_mc_led {
@@ -45,6 +46,9 @@ static int led_pwm_mc_set(struct led_classdev *cdev,
duty *= mc_cdev->subled_info[i].brightness;
do_div(duty, cdev->max_brightness);

+ if (priv->leds[i].active_low)
+ duty = priv->leds[i].state.period - duty;
+
priv->leds[i].state.duty_cycle = duty;
priv->leds[i].state.enabled = duty > 0;
ret = pwm_apply_state(priv->leds[i].pwm,
@@ -76,6 +80,7 @@ static int iterate_subleds(struct device *dev, struct pwm_mc_led *priv,
goto release_fwnode;
}
pwm_init_state(pwmled->pwm, &pwmled->state);
+ pwmled->active_low = fwnode_property_read_bool(fwnode, "active-low");

ret = fwnode_property_read_u32(fwnode, "color", &color);
if (ret) {
--
2.37.0