zephyr/drivers/pwm/pwm_litex.c

89 lines
2.1 KiB
C

/*
* Copyright (c) 2019 Antmicro <www.antmicro.com>
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT litex_pwm
#include <zephyr/device.h>
#include <zephyr/drivers/pwm.h>
#include <zephyr/types.h>
#include <soc.h>
#define REG_EN_ENABLE 0x1
#define REG_EN_DISABLE 0x0
/* PWM device in LiteX has only one channel */
#define NUMBER_OF_CHANNELS 1
struct pwm_litex_cfg {
uint32_t reg_en;
uint32_t reg_width;
uint32_t reg_period;
};
int pwm_litex_init(const struct device *dev)
{
const struct pwm_litex_cfg *cfg = dev->config;
litex_write8(REG_EN_ENABLE, cfg->reg_en);
return 0;
}
int pwm_litex_set_cycles(const struct device *dev, uint32_t channel,
uint32_t period_cycles,
uint32_t pulse_cycles, pwm_flags_t flags)
{
const struct pwm_litex_cfg *cfg = dev->config;
if (channel >= NUMBER_OF_CHANNELS) {
return -EINVAL;
}
litex_write8(REG_EN_DISABLE, cfg->reg_en);
litex_write32(pulse_cycles, cfg->reg_width);
litex_write32(period_cycles, cfg->reg_period);
litex_write8(REG_EN_ENABLE, cfg->reg_en);
return 0;
}
int pwm_litex_get_cycles_per_sec(const struct device *dev, uint32_t channel,
uint64_t *cycles)
{
if (channel >= NUMBER_OF_CHANNELS) {
return -EINVAL;
}
*cycles = sys_clock_hw_cycles_per_sec();
return 0;
}
static const struct pwm_driver_api pwm_litex_driver_api = {
.set_cycles = pwm_litex_set_cycles,
.get_cycles_per_sec = pwm_litex_get_cycles_per_sec,
};
/* Device Instantiation */
#define PWM_LITEX_INIT(n) \
static const struct pwm_litex_cfg pwm_litex_cfg_##n = { \
.reg_en = DT_INST_REG_ADDR_BY_NAME(n, enable), \
.reg_width = DT_INST_REG_ADDR_BY_NAME(n, width), \
.reg_period = DT_INST_REG_ADDR_BY_NAME(n, period), \
}; \
\
DEVICE_DT_INST_DEFINE(n, \
pwm_litex_init, \
NULL, \
NULL, \
&pwm_litex_cfg_##n, \
POST_KERNEL, \
CONFIG_PWM_LITEX_INIT_PRIORITY, \
&pwm_litex_driver_api \
);
DT_INST_FOREACH_STATUS_OKAY(PWM_LITEX_INIT)