blob: e96bc345e652f7d296c9d001bcaf47818267261b [file] [log] [blame]
/*
* Copyright (c) 2019 Aurelien Jarno
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT atmel_sam_pwm
#include <device.h>
#include <errno.h>
#include <drivers/pwm.h>
#include <soc.h>
#define LOG_LEVEL CONFIG_PWM_LOG_LEVEL
#include <logging/log.h>
LOG_MODULE_REGISTER(pwm_sam);
struct sam_pwm_config {
Pwm *regs;
uint32_t id;
uint8_t prescaler;
uint8_t divider;
};
#define DEV_CFG(dev) \
((const struct sam_pwm_config * const)(dev)->config)
static int sam_pwm_get_cycles_per_sec(const struct device *dev, uint32_t pwm,
uint64_t *cycles)
{
uint8_t prescaler = DEV_CFG(dev)->prescaler;
uint8_t divider = DEV_CFG(dev)->divider;
*cycles = SOC_ATMEL_SAM_MCK_FREQ_HZ /
((1 << prescaler) * divider);
return 0;
}
static int sam_pwm_pin_set(const struct device *dev, uint32_t ch,
uint32_t period_cycles, uint32_t pulse_cycles,
pwm_flags_t flags)
{
Pwm *const pwm = DEV_CFG(dev)->regs;
if (ch >= PWMCHNUM_NUMBER) {
return -EINVAL;
}
if (flags) {
/* PWM polarity not supported (yet?) */
return -ENOTSUP;
}
if (period_cycles == 0U || pulse_cycles > period_cycles) {
return -EINVAL;
}
if (period_cycles > 0xffff) {
return -ENOTSUP;
}
/* Select clock A */
pwm->PWM_CH_NUM[ch].PWM_CMR = PWM_CMR_CPRE_CLKA_Val;
/* Update period and pulse using the update registers, so that the
* change is triggered at the next PWM period.
*/
pwm->PWM_CH_NUM[ch].PWM_CPRDUPD = period_cycles;
pwm->PWM_CH_NUM[ch].PWM_CDTYUPD = pulse_cycles;
/* Enable the output */
pwm->PWM_ENA = 1 << ch;
return 0;
}
static int sam_pwm_init(const struct device *dev)
{
Pwm *const pwm = DEV_CFG(dev)->regs;
uint32_t id = DEV_CFG(dev)->id;
uint8_t prescaler = DEV_CFG(dev)->prescaler;
uint8_t divider = DEV_CFG(dev)->divider;
/* FIXME: way to validate prescaler & divider */
/* Enable the PWM peripheral */
soc_pmc_peripheral_enable(id);
/* Configure the clock A that will be used by all 4 channels */
pwm->PWM_CLK = PWM_CLK_PREA(prescaler) | PWM_CLK_DIVA(divider);
return 0;
}
static const struct pwm_driver_api sam_pwm_driver_api = {
.pin_set = sam_pwm_pin_set,
.get_cycles_per_sec = sam_pwm_get_cycles_per_sec,
};
#define SAM_INST_INIT(inst) \
static const struct sam_pwm_config sam_pwm_config_##inst = { \
.regs = (Pwm *)DT_INST_REG_ADDR(inst), \
.id = DT_INST_PROP(inst, peripheral_id), \
.prescaler = DT_INST_PROP(inst, prescaler), \
.divider = DT_INST_PROP(inst, divider), \
}; \
\
DEVICE_DT_INST_DEFINE(inst, \
&sam_pwm_init, NULL, \
NULL, &sam_pwm_config_##inst, \
POST_KERNEL, \
CONFIG_KERNEL_INIT_PRIORITY_DEVICE, \
&sam_pwm_driver_api);
DT_INST_FOREACH_STATUS_OKAY(SAM_INST_INIT)