blob: 7ca6afeb16b2a27b73182631a57345860733d6d2 [file] [log] [blame]
/*
* Copyright (c) 2020 Seagate Technology LLC
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT pwm_leds
/**
* @file
* @brief PWM driven LEDs
*/
#include <drivers/led.h>
#include <drivers/pwm.h>
#include <device.h>
#include <zephyr.h>
#include <sys/math_extras.h>
#include <logging/log.h>
LOG_MODULE_REGISTER(led_pwm, CONFIG_LED_LOG_LEVEL);
#define DEV_CFG(dev) ((const struct led_pwm_config *) ((dev)->config))
struct led_pwm {
const struct device *dev;
uint32_t channel;
uint32_t period;
pwm_flags_t flags;
};
struct led_pwm_config {
int num_leds;
const struct led_pwm *led;
};
static int led_pwm_blink(const struct device *dev, uint32_t led,
uint32_t delay_on, uint32_t delay_off)
{
const struct led_pwm_config *config = DEV_CFG(dev);
const struct led_pwm *led_pwm;
uint32_t period_usec, pulse_usec;
if (led >= config->num_leds) {
return -EINVAL;
}
/*
* Convert delays (in ms) into PWM period and pulse (in us) and check
* for overflows.
*/
if (u32_add_overflow(delay_on, delay_off, &period_usec) ||
u32_mul_overflow(period_usec, 1000, &period_usec) ||
u32_mul_overflow(delay_on, 1000, &pulse_usec)) {
return -EINVAL;
}
led_pwm = &config->led[led];
return pwm_pin_set_usec(led_pwm->dev, led_pwm->channel,
period_usec, pulse_usec, led_pwm->flags);
}
static int led_pwm_set_brightness(const struct device *dev,
uint32_t led, uint8_t value)
{
const struct led_pwm_config *config = DEV_CFG(dev);
const struct led_pwm *led_pwm;
uint32_t pulse;
if (led >= config->num_leds || value > 100) {
return -EINVAL;
}
led_pwm = &config->led[led];
pulse = led_pwm->period * value / 100;
return pwm_pin_set_cycles(led_pwm->dev, led_pwm->channel,
led_pwm->period, pulse, led_pwm->flags);
}
static int led_pwm_on(const struct device *dev, uint32_t led)
{
return led_pwm_set_brightness(dev, led, 100);
}
static int led_pwm_off(const struct device *dev, uint32_t led)
{
return led_pwm_set_brightness(dev, led, 0);
}
static int led_pwm_init(const struct device *dev)
{
const struct led_pwm_config *config = DEV_CFG(dev);
int i;
if (!config->num_leds) {
LOG_ERR("%s: no LEDs found (DT child nodes missing)",
dev->name);
return -ENODEV;
}
for (i = 0; i < config->num_leds; i++) {
const struct led_pwm *led = &config->led[i];
if (!device_is_ready(led->dev)) {
LOG_ERR("%s: pwm device not ready", dev->name);
return -ENODEV;
}
}
return 0;
}
#ifdef CONFIG_PM_DEVICE
static int led_pwm_pm_control(const struct device *dev,
enum pm_device_action action)
{
const struct led_pwm_config *config = DEV_CFG(dev);
/* switch all underlying PWM devices to the new state */
for (size_t i = 0; i < config->num_leds; i++) {
int err;
enum pm_device_state state;
const struct led_pwm *led_pwm = &config->led[i];
LOG_DBG("Switching PWM %p to state %" PRIu32, led_pwm->dev, state);
/* NOTE: temporary solution, deserves proper fix */
switch (action) {
case PM_DEVICE_ACTION_RESUME:
state = PM_DEVICE_STATE_ACTIVE;
break;
case PM_DEVICE_ACTION_SUSPEND:
state = PM_DEVICE_STATE_SUSPENDED;
break;
default:
return -ENOTSUP;
}
err = pm_device_state_set(led_pwm->dev, state);
if (err) {
LOG_ERR("Cannot switch PWM %p power state", led_pwm->dev);
}
}
return 0;
}
#endif /* CONFIG_PM_DEVICE */
static const struct led_driver_api led_pwm_api = {
.on = led_pwm_on,
.off = led_pwm_off,
.blink = led_pwm_blink,
.set_brightness = led_pwm_set_brightness,
};
#define LED_PWM(led_node_id) \
{ \
.dev = DEVICE_DT_GET(DT_PWMS_CTLR(led_node_id)), \
.channel = DT_PWMS_CHANNEL(led_node_id), \
.period = DT_PHA_OR(led_node_id, pwms, period, 100), \
.flags = DT_PHA_OR(led_node_id, pwms, flags, \
PWM_POLARITY_NORMAL), \
},
#define LED_PWM_DEVICE(id) \
\
static const struct led_pwm led_pwm_##id[] = { \
DT_INST_FOREACH_CHILD(id, LED_PWM) \
}; \
\
static const struct led_pwm_config led_pwm_config_##id = { \
.num_leds = ARRAY_SIZE(led_pwm_##id), \
.led = led_pwm_##id, \
}; \
\
DEVICE_DT_INST_DEFINE(id, &led_pwm_init, led_pwm_pm_control, \
NULL, &led_pwm_config_##id, POST_KERNEL, \
CONFIG_LED_INIT_PRIORITY, &led_pwm_api);
DT_INST_FOREACH_STATUS_OKAY(LED_PWM_DEVICE)