zephyr/drivers/pwm/pwm_gecko.c

119 lines
3.3 KiB
C

/*
* Copyright (c) 2021 Sun Amar.
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT silabs_gecko_pwm
#include <zephyr/drivers/pwm.h>
#include <zephyr/dt-bindings/pwm/pwm.h>
#include <em_cmu.h>
#include <em_timer.h>
/** PWM configuration. */
struct pwm_gecko_config {
TIMER_TypeDef *timer;
CMU_Clock_TypeDef clock;
uint16_t prescaler;
TIMER_Prescale_TypeDef prescale_enum;
uint8_t channel;
uint8_t location;
uint8_t port;
uint8_t pin;
};
static int pwm_gecko_set_cycles(const struct device *dev, uint32_t channel,
uint32_t period_cycles, uint32_t pulse_cycles,
pwm_flags_t flags)
{
TIMER_InitCC_TypeDef compare_config = TIMER_INITCC_DEFAULT;
const struct pwm_gecko_config *cfg = dev->config;
if (BUS_RegMaskedRead(&cfg->timer->CC[channel].CTRL,
_TIMER_CC_CTRL_MODE_MASK) != timerCCModePWM) {
#ifdef _TIMER_ROUTE_MASK
BUS_RegMaskedWrite(&cfg->timer->ROUTE,
_TIMER_ROUTE_LOCATION_MASK,
cfg->location << _TIMER_ROUTE_LOCATION_SHIFT);
BUS_RegMaskedSet(&cfg->timer->ROUTE, 1 << channel);
#elif defined(_TIMER_ROUTELOC0_MASK)
BUS_RegMaskedWrite(&cfg->timer->ROUTELOC0,
_TIMER_ROUTELOC0_CC0LOC_MASK <<
(channel * _TIMER_ROUTELOC0_CC1LOC_SHIFT),
cfg->location << (channel * _TIMER_ROUTELOC0_CC1LOC_SHIFT));
BUS_RegMaskedSet(&cfg->timer->ROUTEPEN, 1 << channel);
#else
#error Unsupported device
#endif
compare_config.mode = timerCCModePWM;
TIMER_InitCC(cfg->timer, channel, &compare_config);
}
cfg->timer->CC[channel].CTRL |= (flags & PWM_POLARITY_INVERTED) ?
TIMER_CC_CTRL_OUTINV : 0;
TIMER_TopSet(cfg->timer, period_cycles);
TIMER_CompareBufSet(cfg->timer, channel, pulse_cycles);
return 0;
}
static int pwm_gecko_get_cycles_per_sec(const struct device *dev,
uint32_t channel, uint64_t *cycles)
{
const struct pwm_gecko_config *cfg = dev->config;
*cycles = CMU_ClockFreqGet(cfg->clock) / cfg->prescaler;
return 0;
}
static const struct pwm_driver_api pwm_gecko_driver_api = {
.set_cycles = pwm_gecko_set_cycles,
.get_cycles_per_sec = pwm_gecko_get_cycles_per_sec,
};
static int pwm_gecko_init(const struct device *dev)
{
TIMER_Init_TypeDef timer = TIMER_INIT_DEFAULT;
const struct pwm_gecko_config *cfg = dev->config;
CMU_ClockEnable(cfg->clock, true);
CMU_ClockEnable(cmuClock_GPIO, true);
GPIO_PinModeSet(cfg->port, cfg->pin, gpioModePushPull, 0);
timer.prescale = cfg->prescale_enum;
TIMER_Init(cfg->timer, &timer);
return 0;
}
#define CLOCK_TIMER(id) _CONCAT(cmuClock_TIMER, id)
#define PRESCALING_FACTOR(factor) \
((_CONCAT(timerPrescale, factor)))
#define PWM_GECKO_INIT(index) \
static const struct pwm_gecko_config pwm_gecko_config_##index = { \
.timer = (TIMER_TypeDef *)DT_REG_ADDR(DT_INST_PARENT(index)), \
.clock = CLOCK_TIMER(index), \
.prescaler = DT_INST_PROP(index, prescaler), \
.prescale_enum = (TIMER_Prescale_TypeDef) \
PRESCALING_FACTOR(DT_INST_PROP(index, prescaler)), \
.location = DT_INST_PROP_BY_IDX(index, pin_location, 0), \
.port = (GPIO_Port_TypeDef) \
DT_INST_PROP_BY_IDX(index, pin_location, 1), \
.pin = DT_INST_PROP_BY_IDX(index, pin_location, 2), \
}; \
\
DEVICE_DT_INST_DEFINE(index, &pwm_gecko_init, NULL, NULL, \
&pwm_gecko_config_##index, POST_KERNEL, \
CONFIG_PWM_INIT_PRIORITY, \
&pwm_gecko_driver_api);
DT_INST_FOREACH_STATUS_OKAY(PWM_GECKO_INIT)