/*
* Copyright (c) 2018, Cue Health Inc
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <nrfx_pwm.h>
#include <pwm.h>
#include <hal/nrf_gpio.h>
#include <stdbool.h>
#define LOG_LEVEL CONFIG_PWM_LOG_LEVEL
#include <logging/log.h>
LOG_MODULE_REGISTER(pwm_nrfx);
#define PWM_NRFX_CH_POLARITY_MASK BIT(15)
#define PWM_NRFX_CH_PULSE_CYCLES_MASK BIT_MASK(15)
#define PWM_NRFX_CH_VALUE_NORMAL PWM_NRFX_CH_POLARITY_MASK
#define PWM_NRFX_CH_VALUE_INVERTED (0)
#define PWM_NRFX_CH_PIN_MASK ~NRFX_PWM_PIN_INVERTED
struct pwm_nrfx_config {
nrfx_pwm_t pwm;
nrfx_pwm_config_t initial_config;
nrf_pwm_sequence_t seq;
};
struct pwm_nrfx_data {
u32_t period_cycles;
u16_t current[NRF_PWM_CHANNEL_COUNT];
u16_t countertop;
u8_t prescaler;
};
static u32_t pwm_period_check_and_set(const struct pwm_nrfx_config *config,
struct pwm_nrfx_data *data,
u32_t pwm,
u32_t period_cycles)
{
NRF_PWM_Type *pwm_instance = config->pwm.p_registers;
if (!nrfx_pwm_is_stopped(&config->pwm)) {
/* Succeed if requested period matches already used period */
if (period_cycles == data->period_cycles) {
return 0;
}
/* Fail if requested period != already running period */
LOG_ERR("Fail:requested period cycles:%d, != used %d\n",
period_cycles, data->period_cycles);
return -EINVAL;
}
/* Check if period_cycles is above COUNTERTOP MAX value, if so, we
* have to see if we can change frequency to something that will fit
*/
if (period_cycles > PWM_COUNTERTOP_COUNTERTOP_Msk) {
/* See if there is a prescaler that will make it work: */
bool matching_prescaler_found = false;
/* Go through all available prescaler values on device (skip 0
* here as it is used in the 'else' block).
* nRF52832 has 0-7 (Div1 - Div128)
*/
for (u8_t prescaler = 1;
prescaler <= PWM_PRESCALER_PRESCALER_Msk;
prescaler++) {
u32_t new_countertop = period_cycles >> prescaler;
/* If we find value that fits, set it, continue */
if (new_countertop <= PWM_COUNTERTOP_COUNTERTOP_Msk) {
data->prescaler = prescaler;
data->countertop = new_countertop;
data->period_cycles = period_cycles;
matching_prescaler_found = true;
break;
}
}
/* Check if able to find matching prescaler and countertop */
if (matching_prescaler_found == false) {
LOG_ERR("Prescaler for period_cycles %d not found.\n",
period_cycles);
return -EINVAL;
}
} else {
/* If period_cycles fit the PWM counter without dividing
* the PWM clock, use the zero prescaler.
*/
data->prescaler = 0U;
data->countertop = period_cycles;
data->period_cycles = period_cycles;
}
/* Write new PRESCALER and COUNTERTOP to PWM instance */
nrf_pwm_configure(pwm_instance,
data->prescaler,
config->initial_config.count_mode,
data->countertop);
return 0;
}
static u8_t pwm_channel_map(const uint8_t *output_pins, u32_t pwm)
{
u8_t i;
/* Find pin, return channel number */
for (i = 0U; i < NRF_PWM_CHANNEL_COUNT; i++) {
if (output_pins[i] != NRFX_PWM_PIN_NOT_USED
&& (pwm == (output_pins[i] & PWM_NRFX_CH_PIN_MASK))) {
return i;
}
}
/* Return NRF_PWM_CHANNEL_COUNT to show that PWM pin was not found. */
return NRF_PWM_CHANNEL_COUNT;
}
static bool any_channel_active(const struct pwm_nrfx_data *data)
{
u8_t channel;
for (channel = 0U; channel < NRF_PWM_CHANNEL_COUNT; channel++) {
u16_t channel_pulse_cycle =
data->current[channel]
& PWM_NRFX_CH_PULSE_CYCLES_MASK;
if (channel_pulse_cycle > 0
&& channel_pulse_cycle < data->countertop) {
return true;
}
}
return false;
}
static int pwm_nrfx_pin_set(struct device *dev, u32_t pwm,
u32_t period_cycles, u32_t pulse_cycles)
{
/* We assume here that period_cycles will always be 16MHz
* peripheral clock. Since pwm_nrfx_get_cycles_per_sec() function might
* be removed, see ISSUE #6958.
* TODO: Remove this comment when issue has been resolved.
*/
const struct pwm_nrfx_config *config = dev->config->config_info;
struct pwm_nrfx_data *data = dev->driver_data;
u8_t channel;
u32_t ret;
/* Check if PWM pin is one of the predefiend DTS config pins.
* Return its array index (channel number),
* or NRF_PWM_CHANNEL_COUNT if not initialized through DTS.
*/
channel = pwm_channel_map(config->initial_config.output_pins, pwm);
if (channel == NRF_PWM_CHANNEL_COUNT) {
LOG_ERR("PWM pin %d not enabled through DTS configuration.",
pwm);
return -EINVAL;
}
/* Check if period_cycle is either matching currently used, or
* possible to use with our prescaler options.
*/
ret = pwm_period_check_and_set(config, data, pwm, period_cycles);
if (ret) {
LOG_ERR("Incompatible period %d", period_cycles);
return ret;
}
/* Check if pulse is bigger than period, fail if so */
if (pulse_cycles > period_cycles) {
LOG_ERR("Invalid pulse_cycles %d, > period_cycles %d.",
pulse_cycles, period_cycles);
return -EINVAL;
}
/* Store new pulse value bit[14:0], and polarity bit[15] for channel. */
data->current[channel] = (
(data->current[channel] & PWM_NRFX_CH_POLARITY_MASK)
| (pulse_cycles >> data->prescaler));
/* If Channel is off/fully on (duty 0% or 100%), also set GPIO register
* since this will the setting if we in the future disable the
* peripheral when no channels are active.
*/
if (pulse_cycles == 0U || pulse_cycles == period_cycles) {
/* If pulse 0% and pin not inverted, set LOW.
* If pulse 100% and pin inverted, set LOW.
* If pulse 0% and pin inverted, set HIGH.
* If pulse 100% and pin not inverted, set HIGH.
*/
bool channel_inverted_state =
config->initial_config.output_pins[channel]
& NRFX_PWM_PIN_INVERTED;
bool pulse_0_and_not_inverted =
(pulse_cycles == 0U)
&& !channel_inverted_state;
bool pulse_100_and_inverted =
(pulse_cycles == period_cycles)
&& channel_inverted_state;
if (pulse_0_and_not_inverted || pulse_100_and_inverted) {
nrf_gpio_pin_clear(pwm);
} else {
nrf_gpio_pin_set(pwm);
}
}
/* Check if all channels are off (duty 0% or 100%) */
if (!any_channel_active(data)) {
nrfx_pwm_stop(&config->pwm, false);
} else {
/* A PWM Channel is active: Start sequence. */
/* Since we are playing the sequence in a loop, the
* sequence only has to be started when its not already
* playing. The new channel values will be used
* immediately when they are written into the seq array.
*/
nrfx_pwm_simple_playback(&config->pwm,
&config->seq,
1,
NRFX_PWM_FLAG_LOOP);
}
return 0;
}
static int pwm_nrfx_get_cycles_per_sec(struct device *dev, u32_t pwm,
u64_t *cycles)
{
/* TODO: Since this function might be removed, we will always return
* 16MHz from this function and handle the conversion with prescaler,
* etc, in the pin set function. See issue #6958.
*/
*cycles = 16ul * 1000ul * 1000ul;
return 0;
}
static const struct pwm_driver_api pwm_nrfx_drv_api_funcs = {
.pin_set = pwm_nrfx_pin_set,
.get_cycles_per_sec = pwm_nrfx_get_cycles_per_sec,
};
static int pwm_nrfx_init(struct device *dev)
{
const struct pwm_nrfx_config *config = dev->config->config_info;
nrfx_err_t result = nrfx_pwm_init(&config->pwm,
&config->initial_config,
NULL);
if (result != NRFX_SUCCESS) {
LOG_ERR("Failed to initialize device: %s", dev->config->name);
return -EBUSY;
}
return 0;
}
#ifdef CONFIG_DEVICE_POWER_MANAGEMENT
static void pwm_nrfx_uninit(struct device *dev)
{
const struct pwm_nrfx_config *config = dev->config->config_info;
nrfx_pwm_uninit(&config->pwm);
}
static int pwm_nrfx_set_power_state(u32_t new_state,
u32_t current_state,
struct device *dev)
{
int err = 0;
switch (new_state) {
case DEVICE_PM_ACTIVE_STATE:
err = pwm_nrfx_init(dev);
break;
case DEVICE_PM_LOW_POWER_STATE:
case DEVICE_PM_SUSPEND_STATE:
case DEVICE_PM_FORCE_SUSPEND_STATE:
case DEVICE_PM_OFF_STATE:
if (current_state == DEVICE_PM_ACTIVE_STATE) {
pwm_nrfx_uninit(dev);
}
break;
default:
assert(false);
break;
}
return err;
}
static int pwm_nrfx_pm_control(struct device *dev,
u32_t ctrl_command,
void *context,
u32_t *current_state)
{
int err = 0;
if (ctrl_command == DEVICE_PM_SET_POWER_STATE) {
u32_t new_state = *((const u32_t *)context);
if (new_state != (*current_state)) {
err = pwm_nrfx_set_power_state(new_state,
*current_state,
dev);
if (!err) {
(*current_state) = new_state;
}
}
} else {
assert(ctrl_command == DEVICE_PM_GET_POWER_STATE);
*((u32_t *)context) = (*current_state);
}
return err;
}
#define PWM_NRFX_PM_CONTROL(idx) \
static int pwm_##idx##_nrfx_pm_control(struct device *dev, \
u32_t ctrl_command, \
void *context, \
device_pm_cb cb, \
void *arg) \
{ \
static u32_t current_state = DEVICE_PM_ACTIVE_STATE; \
int ret = 0; \
ret = pwm_nrfx_pm_control(dev, ctrl_command, context, \
¤t_state); \
if (cb) { \
cb(dev, ret, context, arg); \
} \
return ret; \
}
#else
#define PWM_NRFX_PM_CONTROL(idx)
#endif /* CONFIG_DEVICE_POWER_MANAGEMENT */
#define PWM_NRFX_OUTPUT_PIN(dev_idx, ch_idx) \
(DT_NORDIC_NRF_PWM_PWM_##dev_idx##_CH##ch_idx##_PIN | \
(DT_NORDIC_NRF_PWM_PWM_##dev_idx##_CH##ch_idx##_INVERTED ? \
NRFX_PWM_PIN_INVERTED : 0))
#define PWM_NRFX_DEFAULT_VALUE(dev_idx, ch_idx) \
(DT_NORDIC_NRF_PWM_PWM_##dev_idx##_CH##ch_idx##_INVERTED ? \
PWM_NRFX_CH_VALUE_INVERTED : PWM_NRFX_CH_VALUE_NORMAL)
#define PWM_NRFX_DEVICE(idx) \
static struct pwm_nrfx_data pwm_nrfx_##idx##_data = { \
.current = { \
PWM_NRFX_DEFAULT_VALUE(idx, 0), \
PWM_NRFX_DEFAULT_VALUE(idx, 1), \
PWM_NRFX_DEFAULT_VALUE(idx, 2), \
PWM_NRFX_DEFAULT_VALUE(idx, 3), \
}, \
.countertop = NRFX_PWM_DEFAULT_CONFIG_TOP_VALUE, \
.prescaler = NRFX_PWM_DEFAULT_CONFIG_BASE_CLOCK \
}; \
static const struct pwm_nrfx_config pwm_nrfx_##idx##z_config = { \
.pwm = NRFX_PWM_INSTANCE(idx), \
.initial_config = { \
.output_pins = { \
PWM_NRFX_OUTPUT_PIN(idx, 0), \
PWM_NRFX_OUTPUT_PIN(idx, 1), \
PWM_NRFX_OUTPUT_PIN(idx, 2), \
PWM_NRFX_OUTPUT_PIN(idx, 3), \
}, \
.base_clock = NRFX_PWM_DEFAULT_CONFIG_BASE_CLOCK, \
.count_mode = NRF_PWM_MODE_UP, \
.top_value = NRFX_PWM_DEFAULT_CONFIG_TOP_VALUE, \
.load_mode = NRF_PWM_LOAD_INDIVIDUAL, \
.step_mode = NRF_PWM_STEP_TRIGGERED, \
}, \
.seq.values.p_raw = pwm_nrfx_##idx##_data.current, \
.seq.length = NRF_PWM_CHANNEL_COUNT \
}; \
PWM_NRFX_PM_CONTROL(idx) \
DEVICE_DEFINE(pwm_nrfx_##idx, \
DT_NORDIC_NRF_PWM_PWM_##idx##_LABEL, \
pwm_nrfx_init, pwm_##idx##_nrfx_pm_control, \
&pwm_nrfx_##idx##_data, \
&pwm_nrfx_##idx##z_config, \
POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE, \
&pwm_nrfx_drv_api_funcs)
#ifdef CONFIG_PWM_0
#ifndef DT_NORDIC_NRF_PWM_PWM_0_CH0_PIN
#define DT_NORDIC_NRF_PWM_PWM_0_CH0_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_0_CH0_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_0_CH0_INVERTED 0
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_0_CH1_PIN
#define DT_NORDIC_NRF_PWM_PWM_0_CH1_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_0_CH1_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_0_CH1_INVERTED 0
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_0_CH2_PIN
#define DT_NORDIC_NRF_PWM_PWM_0_CH2_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_0_CH2_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_0_CH2_INVERTED 0
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_0_CH3_PIN
#define DT_NORDIC_NRF_PWM_PWM_0_CH3_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_0_CH3_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_0_CH3_INVERTED 0
#endif
PWM_NRFX_DEVICE(0);
#endif
#ifdef CONFIG_PWM_1
#ifndef DT_NORDIC_NRF_PWM_PWM_1_CH0_PIN
#define DT_NORDIC_NRF_PWM_PWM_1_CH0_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_1_CH0_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_1_CH0_INVERTED 0
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_1_CH1_PIN
#define DT_NORDIC_NRF_PWM_PWM_1_CH1_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_1_CH1_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_1_CH1_INVERTED 0
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_1_CH2_PIN
#define DT_NORDIC_NRF_PWM_PWM_1_CH2_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_1_CH2_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_1_CH2_INVERTED 0
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_1_CH3_PIN
#define DT_NORDIC_NRF_PWM_PWM_1_CH3_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_1_CH3_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_1_CH3_INVERTED 0
#endif
PWM_NRFX_DEVICE(1);
#endif
#ifdef CONFIG_PWM_2
#ifndef DT_NORDIC_NRF_PWM_PWM_2_CH0_PIN
#define DT_NORDIC_NRF_PWM_PWM_2_CH0_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_2_CH0_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_2_CH0_INVERTED 0
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_2_CH1_PIN
#define DT_NORDIC_NRF_PWM_PWM_2_CH1_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_2_CH1_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_2_CH1_INVERTED 0
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_2_CH2_PIN
#define DT_NORDIC_NRF_PWM_PWM_2_CH2_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_2_CH2_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_2_CH2_INVERTED 0
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_2_CH3_PIN
#define DT_NORDIC_NRF_PWM_PWM_2_CH3_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_2_CH3_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_2_CH3_INVERTED 0
#endif
PWM_NRFX_DEVICE(2);
#endif
#ifdef CONFIG_PWM_3
#ifndef DT_NORDIC_NRF_PWM_PWM_3_CH0_PIN
#define DT_NORDIC_NRF_PWM_PWM_3_CH0_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_3_CH0_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_3_CH0_INVERTED 0
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_3_CH1_PIN
#define DT_NORDIC_NRF_PWM_PWM_3_CH1_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_3_CH1_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_3_CH1_INVERTED 0
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_3_CH2_PIN
#define DT_NORDIC_NRF_PWM_PWM_3_CH2_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_3_CH2_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_3_CH2_INVERTED 0
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_3_CH3_PIN
#define DT_NORDIC_NRF_PWM_PWM_3_CH3_PIN NRFX_PWM_PIN_NOT_USED
#endif
#ifndef DT_NORDIC_NRF_PWM_PWM_3_CH3_INVERTED
#define DT_NORDIC_NRF_PWM_PWM_3_CH3_INVERTED 0
#endif
PWM_NRFX_DEVICE(3);
#endif
