zephyr/drivers/pwm/pwm_b91.c

143 lines
3.6 KiB
C

/*
* Copyright (c) 2021 Telink Semiconductor
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT telink_b91_pwm
#include "pwm.h"
#include "clock.h"
#include <drivers/pwm.h>
#include <drivers/pinmux.h>
#include <dt-bindings/pinctrl/b91-pinctrl.h>
#define PWM_PCLK_SPEED DT_INST_PROP(0, clock_frequency)
#define NUM_OF_CHANNELS DT_INST_PROP(0, channels)
static const uint32_t pwm_pins[] = B91_PINMUX_DT_INST_GET_ARRAY(0, 0);
/* API implementation: init */
static int pwm_b91_init(const struct device *dev)
{
ARG_UNUSED(dev);
uint8_t clk_32k_en = 0;
uint32_t pwm_clk_div = 0;
const struct device *pinmux;
/* Calculate and check PWM clock divider */
pwm_clk_div = sys_clk.pclk * 1000 * 1000 / PWM_PCLK_SPEED - 1;
if (pwm_clk_div > 255) {
return -EINVAL;
}
/* Set PWM Peripheral clock */
pwm_set_clk((unsigned char) (pwm_clk_div & 0xFF));
/* Set PWM 32k Channel clock if enabled */
clk_32k_en |= DT_INST_PROP(0, clk32k_ch0_enable) ? PWM_CLOCK_32K_CHN_PWM0 : 0;
clk_32k_en |= DT_INST_PROP(0, clk32k_ch1_enable) ? PWM_CLOCK_32K_CHN_PWM1 : 0;
clk_32k_en |= DT_INST_PROP(0, clk32k_ch2_enable) ? PWM_CLOCK_32K_CHN_PWM2 : 0;
clk_32k_en |= DT_INST_PROP(0, clk32k_ch3_enable) ? PWM_CLOCK_32K_CHN_PWM3 : 0;
clk_32k_en |= DT_INST_PROP(0, clk32k_ch4_enable) ? PWM_CLOCK_32K_CHN_PWM4 : 0;
clk_32k_en |= DT_INST_PROP(0, clk32k_ch5_enable) ? PWM_CLOCK_32K_CHN_PWM5 : 0;
pwm_32k_chn_en(clk_32k_en);
/* Get PinMux driver */
pinmux = DEVICE_DT_GET(DT_NODELABEL(pinmux));
if (!device_is_ready(pinmux)) {
return -ENODEV;
}
/* Config PWM pins */
for (int i = 0; i < ARRAY_SIZE(pwm_pins); i++) {
pinmux_pin_set(pinmux, B91_PINMUX_GET_PIN(pwm_pins[i]),
B91_PINMUX_GET_FUNC(pwm_pins[i]));
}
return 0;
}
/* API implementation: pin_set */
static int pwm_b91_pin_set(const struct device *dev, uint32_t pwm,
uint32_t period_cycles, uint32_t pulse_cycles,
pwm_flags_t flags)
{
ARG_UNUSED(dev);
/* check pwm channel */
if (pwm >= NUM_OF_CHANNELS) {
return -EINVAL;
}
/* check size of pulse and period (2 bytes) */
if ((period_cycles > 0xFFFFu) ||
(pulse_cycles > 0xFFFFu)) {
return -EINVAL;
}
/* set polarity */
if (flags & PWM_POLARITY_INVERTED) {
pwm_invert_en(pwm);
} else {
pwm_invert_dis(pwm);
}
/* set pulse and period */
pwm_set_tcmp(pwm, pulse_cycles);
pwm_set_tmax(pwm, period_cycles);
/* start pwm */
pwm_start(pwm);
return 0;
}
/* API implementation: get_cycles_per_sec */
static int pwm_b91_get_cycles_per_sec(const struct device *dev, uint32_t pwm,
uint64_t *cycles)
{
ARG_UNUSED(dev);
/* check pwm channel */
if (pwm >= NUM_OF_CHANNELS) {
return -EINVAL;
}
if (
((pwm == 0u) && DT_INST_PROP(0, clk32k_ch0_enable)) ||
((pwm == 1u) && DT_INST_PROP(0, clk32k_ch1_enable)) ||
((pwm == 2u) && DT_INST_PROP(0, clk32k_ch2_enable)) ||
((pwm == 3u) && DT_INST_PROP(0, clk32k_ch3_enable)) ||
((pwm == 4u) && DT_INST_PROP(0, clk32k_ch4_enable)) ||
((pwm == 5u) && DT_INST_PROP(0, clk32k_ch5_enable))
) {
*cycles = 32000u;
} else {
*cycles = sys_clk.pclk * 1000 * 1000 / (reg_pwm_clkdiv + 1);
}
return 0;
}
/* PWM driver APIs structure */
static const struct pwm_driver_api pwm_b91_driver_api = {
.pin_set = pwm_b91_pin_set,
.get_cycles_per_sec = pwm_b91_get_cycles_per_sec,
};
BUILD_ASSERT(DT_NUM_INST_STATUS_OKAY(DT_DRV_COMPAT) <= 1,
"unsupported PWM instance");
/* PWM driver registration */
#define PWM_B91_INIT(n) \
\
DEVICE_DT_INST_DEFINE(n, pwm_b91_init, \
NULL, NULL, NULL, \
POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE, \
&pwm_b91_driver_api);
DT_INST_FOREACH_STATUS_OKAY(PWM_B91_INIT)