esp-idf/components/esp_driver_pcnt/src/pulse_cnt.c

864 wiersze
35 KiB
C

/*
* SPDX-FileCopyrightText: 2021-2023 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <stdint.h>
#include <sys/lock.h>
#include "sdkconfig.h"
#if CONFIG_PCNT_ENABLE_DEBUG_LOG
// The local log level must be defined before including esp_log.h
// Set the maximum log level for this source file
#define LOG_LOCAL_LEVEL ESP_LOG_DEBUG
#endif
#include "freertos/FreeRTOS.h"
#include "esp_heap_caps.h"
#include "esp_intr_alloc.h"
#include "esp_attr.h"
#include "esp_log.h"
#include "esp_check.h"
#include "esp_pm.h"
#include "esp_rom_gpio.h"
#include "soc/soc_caps.h"
#include "soc/pcnt_periph.h"
#include "soc/gpio_pins.h"
#include "hal/pcnt_hal.h"
#include "hal/pcnt_ll.h"
#include "hal/gpio_hal.h"
#include "esp_private/esp_clk.h"
#include "esp_private/periph_ctrl.h"
#include "driver/gpio.h"
#include "driver/pulse_cnt.h"
#include "esp_memory_utils.h"
// If ISR handler is allowed to run whilst cache is disabled,
// Make sure all the code and related variables used by the handler are in the SRAM
#if CONFIG_PCNT_ISR_IRAM_SAFE || CONFIG_PCNT_CTRL_FUNC_IN_IRAM
#define PCNT_MEM_ALLOC_CAPS (MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT)
#else
#define PCNT_MEM_ALLOC_CAPS MALLOC_CAP_DEFAULT
#endif
#if CONFIG_PCNT_ISR_IRAM_SAFE
#define PCNT_INTR_ALLOC_FLAGS (ESP_INTR_FLAG_IRAM | ESP_INTR_FLAG_INTRDISABLED | ESP_INTR_FLAG_SHARED)
#else
#define PCNT_INTR_ALLOC_FLAGS (ESP_INTR_FLAG_INTRDISABLED | ESP_INTR_FLAG_SHARED)
#endif
#define PCNT_ALLOW_INTR_PRIORITY_MASK ESP_INTR_FLAG_LOWMED
#define PCNT_PM_LOCK_NAME_LEN_MAX 16
#if !SOC_RCC_IS_INDEPENDENT
#define PCNT_RCC_ATOMIC() PERIPH_RCC_ATOMIC()
#else
#define PCNT_RCC_ATOMIC()
#endif
static const char *TAG = "pcnt";
typedef struct pcnt_platform_t pcnt_platform_t;
typedef struct pcnt_group_t pcnt_group_t;
typedef struct pcnt_unit_t pcnt_unit_t;
typedef struct pcnt_chan_t pcnt_chan_t;
struct pcnt_platform_t {
_lock_t mutex; // platform level mutex lock
pcnt_group_t *groups[SOC_PCNT_GROUPS]; // pcnt group pool
int group_ref_counts[SOC_PCNT_GROUPS]; // reference count used to protect group install/uninstall
};
struct pcnt_group_t {
int group_id; // Group ID, index from 0
int intr_priority; // PCNT interrupt priority
portMUX_TYPE spinlock; // to protect per-group register level concurrent access
pcnt_hal_context_t hal;
pcnt_unit_t *units[SOC_PCNT_UNITS_PER_GROUP]; // array of PCNT units
};
typedef struct {
pcnt_ll_watch_event_id_t event_id; // event type
int watch_point_value; // value to be watched
} pcnt_watch_point_t;
typedef enum {
PCNT_UNIT_FSM_INIT,
PCNT_UNIT_FSM_ENABLE,
} pcnt_unit_fsm_t;
struct pcnt_unit_t {
pcnt_group_t *group; // which group the pcnt unit belongs to
portMUX_TYPE spinlock; // Spinlock, stop one unit from accessing different parts of a same register concurrently
int unit_id; // allocated unit numerical ID
int low_limit; // low limit value
int high_limit; // high limit value
int clear_signal_gpio_num; // which gpio clear signal input
int accum_value; // accumulated count value
pcnt_chan_t *channels[SOC_PCNT_CHANNELS_PER_UNIT]; // array of PCNT channels
pcnt_watch_point_t watchers[PCNT_LL_WATCH_EVENT_MAX]; // array of PCNT watchers
intr_handle_t intr; // interrupt handle
esp_pm_lock_handle_t pm_lock; // PM lock, for glitch filter, as that module can only be functional under APB
#if CONFIG_PM_ENABLE
char pm_lock_name[PCNT_PM_LOCK_NAME_LEN_MAX]; // pm lock name
#endif
pcnt_unit_fsm_t fsm; // record PCNT unit's driver state
pcnt_watch_cb_t on_reach; // user registered callback function
void *user_data; // user data registered by user, which would be passed to the right callback function
struct {
uint32_t accum_count: 1; /*!< Whether to accumulate the count value when overflows at the high/low limit */
} flags;
};
struct pcnt_chan_t {
pcnt_unit_t *unit; // pointer to the PCNT unit where it derives from
int channel_id; // channel ID, index from 0
int edge_gpio_num;
int level_gpio_num;
};
// pcnt driver platform, it's always a singleton
static pcnt_platform_t s_platform;
static pcnt_group_t *pcnt_acquire_group_handle(int group_id);
static void pcnt_release_group_handle(pcnt_group_t *group);
static void pcnt_default_isr(void *args);
static esp_err_t pcnt_register_to_group(pcnt_unit_t *unit)
{
pcnt_group_t *group = NULL;
int unit_id = -1;
for (int i = 0; i < SOC_PCNT_GROUPS; i++) {
group = pcnt_acquire_group_handle(i);
ESP_RETURN_ON_FALSE(group, ESP_ERR_NO_MEM, TAG, "no mem for group (%d)", i);
// loop to search free unit in the group
portENTER_CRITICAL(&group->spinlock);
for (int j = 0; j < SOC_PCNT_UNITS_PER_GROUP; j++) {
if (!group->units[j]) {
unit_id = j;
group->units[j] = unit;
break;
}
}
portEXIT_CRITICAL(&group->spinlock);
if (unit_id < 0) {
pcnt_release_group_handle(group);
} else {
unit->group = group;
unit->unit_id = unit_id;
break;
}
}
ESP_RETURN_ON_FALSE(unit_id != -1, ESP_ERR_NOT_FOUND, TAG, "no free unit");
return ESP_OK;
}
static void pcnt_unregister_from_group(pcnt_unit_t *unit)
{
pcnt_group_t *group = unit->group;
int unit_id = unit->unit_id;
portENTER_CRITICAL(&group->spinlock);
group->units[unit_id] = NULL;
portEXIT_CRITICAL(&group->spinlock);
// unit has a reference on group, release it now
pcnt_release_group_handle(group);
}
static esp_err_t pcnt_destroy(pcnt_unit_t *unit)
{
if (unit->pm_lock) {
ESP_RETURN_ON_ERROR(esp_pm_lock_delete(unit->pm_lock), TAG, "delete pm lock failed");
}
if (unit->intr) {
ESP_RETURN_ON_ERROR(esp_intr_free(unit->intr), TAG, "delete interrupt service failed");
}
if (unit->group) {
pcnt_unregister_from_group(unit);
}
free(unit);
return ESP_OK;
}
esp_err_t pcnt_new_unit(const pcnt_unit_config_t *config, pcnt_unit_handle_t *ret_unit)
{
#if CONFIG_PCNT_ENABLE_DEBUG_LOG
esp_log_level_set(TAG, ESP_LOG_DEBUG);
#endif
esp_err_t ret = ESP_OK;
pcnt_unit_t *unit = NULL;
ESP_GOTO_ON_FALSE(config && ret_unit, ESP_ERR_INVALID_ARG, err, TAG, "invalid argument");
ESP_GOTO_ON_FALSE(config->low_limit < 0 && config->high_limit > 0 && config->low_limit >= PCNT_LL_MIN_LIN &&
config->high_limit <= PCNT_LL_MAX_LIM, ESP_ERR_INVALID_ARG, err, TAG,
"invalid limit range:[%d,%d]", config->low_limit, config->high_limit);
if (config->intr_priority) {
ESP_GOTO_ON_FALSE(1 << (config->intr_priority) & PCNT_ALLOW_INTR_PRIORITY_MASK, ESP_ERR_INVALID_ARG, err,
TAG, "invalid interrupt priority:%d", config->intr_priority);
}
unit = heap_caps_calloc(1, sizeof(pcnt_unit_t), PCNT_MEM_ALLOC_CAPS);
ESP_GOTO_ON_FALSE(unit, ESP_ERR_NO_MEM, err, TAG, "no mem for unit");
// register unit to the group (because one group can have several units)
ESP_GOTO_ON_ERROR(pcnt_register_to_group(unit), err, TAG, "register unit failed");
pcnt_group_t *group = unit->group;
int group_id = group->group_id;
int unit_id = unit->unit_id;
// if interrupt priority specified before, it cannot be changed until the group is released
// check if the new priority specified consistents with the old one
bool intr_priority_conflict = false;
portENTER_CRITICAL(&group->spinlock);
if (group->intr_priority == -1) {
group->intr_priority = config->intr_priority;
} else if (config->intr_priority != 0) {
intr_priority_conflict = (group->intr_priority != config->intr_priority);
}
portEXIT_CRITICAL(&group->spinlock);
ESP_GOTO_ON_FALSE(!intr_priority_conflict, ESP_ERR_INVALID_STATE, err, TAG, "intr_priority conflict, already is %d but attempt to %d", group->intr_priority, config->intr_priority);
// to accumulate count value, we should install the interrupt handler first, and in the ISR we do the accumulation
bool to_install_isr = (config->flags.accum_count == 1);
if (to_install_isr) {
int isr_flags = PCNT_INTR_ALLOC_FLAGS;
if (group->intr_priority) {
isr_flags |= 1 << (group->intr_priority);
} else {
isr_flags |= PCNT_ALLOW_INTR_PRIORITY_MASK;
}
ESP_GOTO_ON_ERROR(esp_intr_alloc_intrstatus(pcnt_periph_signals.groups[group_id].irq, isr_flags,
(uint32_t)pcnt_ll_get_intr_status_reg(group->hal.dev), PCNT_LL_UNIT_WATCH_EVENT(unit_id),
pcnt_default_isr, unit, &unit->intr), err,
TAG, "install interrupt service failed");
}
// some events are enabled by default, disable them all
pcnt_ll_disable_all_events(group->hal.dev, unit_id);
// disable filter by default
pcnt_ll_enable_glitch_filter(group->hal.dev, unit_id, false);
// set default high/low limitation value
// note: limit value takes effect only after counter clear
pcnt_ll_set_high_limit_value(group->hal.dev, unit_id, config->high_limit);
pcnt_ll_set_low_limit_value(group->hal.dev, unit_id, config->low_limit);
unit->high_limit = config->high_limit;
unit->low_limit = config->low_limit;
unit->accum_value = 0;
unit->clear_signal_gpio_num = -1;
unit->flags.accum_count = config->flags.accum_count;
// clear/pause register is shared by all units, so using group's spinlock
portENTER_CRITICAL(&group->spinlock);
pcnt_ll_stop_count(group->hal.dev, unit_id);
pcnt_ll_clear_count(group->hal.dev, unit_id);
// enable the interrupt if we want to accumulate the counter in the ISR
pcnt_ll_enable_intr(group->hal.dev, PCNT_LL_UNIT_WATCH_EVENT(unit_id), to_install_isr);
pcnt_ll_clear_intr_status(group->hal.dev, PCNT_LL_UNIT_WATCH_EVENT(unit_id));
portEXIT_CRITICAL(&group->spinlock);
unit->spinlock = (portMUX_TYPE)portMUX_INITIALIZER_UNLOCKED;
unit->fsm = PCNT_UNIT_FSM_INIT;
for (int i = 0; i < PCNT_LL_WATCH_EVENT_MAX; i++) {
unit->watchers[i].event_id = PCNT_LL_WATCH_EVENT_INVALID; // invalid all watch point
}
ESP_LOGD(TAG, "new pcnt unit (%d,%d) at %p, count range:[%d,%d]", group_id, unit_id, unit, unit->low_limit, unit->high_limit);
*ret_unit = unit;
return ESP_OK;
err:
if (unit) {
pcnt_destroy(unit);
}
return ret;
}
esp_err_t pcnt_del_unit(pcnt_unit_handle_t unit)
{
ESP_RETURN_ON_FALSE(unit, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
ESP_RETURN_ON_FALSE(unit->fsm == PCNT_UNIT_FSM_INIT, ESP_ERR_INVALID_STATE, TAG, "unit not in init state");
pcnt_group_t *group = unit->group;
int group_id = group->group_id;
int unit_id = unit->unit_id;
for (int i = 0; i < SOC_PCNT_CHANNELS_PER_UNIT; i++) {
ESP_RETURN_ON_FALSE(!unit->channels[i], ESP_ERR_INVALID_STATE, TAG, "channel %d still in working", i);
}
#if SOC_PCNT_SUPPORT_CLEAR_SIGNAL
if (unit->clear_signal_gpio_num >= 0) {
gpio_reset_pin(unit->clear_signal_gpio_num);
}
#endif // SOC_PCNT_SUPPORT_CLEAR_SIGNAL
ESP_LOGD(TAG, "del unit (%d,%d)", group_id, unit_id);
// recycle memory resource
ESP_RETURN_ON_ERROR(pcnt_destroy(unit), TAG, "destroy pcnt unit failed");
return ESP_OK;
}
#if SOC_PCNT_SUPPORT_CLEAR_SIGNAL
esp_err_t pcnt_unit_set_clear_signal(pcnt_unit_handle_t unit, const pcnt_clear_signal_config_t *config)
{
ESP_RETURN_ON_FALSE(unit, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
pcnt_group_t *group = unit->group;
int group_id = group->group_id;
int unit_id = unit->unit_id;
if (config) {
gpio_config_t gpio_conf = {
.intr_type = GPIO_INTR_DISABLE,
.mode = GPIO_MODE_INPUT | (config->flags.io_loop_back ? GPIO_MODE_OUTPUT : 0), // also enable the output path if `io_loop_back` is enabled
.pull_down_en = true,
.pull_up_en = false,
};
if (config->flags.invert_clear_signal) {
gpio_conf.pull_down_en = false;
gpio_conf.pull_up_en = true;
}
gpio_conf.pin_bit_mask = 1ULL << config->clear_signal_gpio_num;
ESP_RETURN_ON_ERROR(gpio_config(&gpio_conf), TAG, "config zero signal GPIO failed");
esp_rom_gpio_connect_in_signal(config->clear_signal_gpio_num,
pcnt_periph_signals.groups[group_id].units[unit_id].clear_sig,
config->flags.invert_clear_signal);
unit->clear_signal_gpio_num = config->clear_signal_gpio_num;
} else {
ESP_RETURN_ON_FALSE(unit->clear_signal_gpio_num >= 0, ESP_ERR_INVALID_STATE, TAG, "zero signal not set yet");
gpio_reset_pin(unit->clear_signal_gpio_num);
unit->clear_signal_gpio_num = -1;
}
return ESP_OK;
}
#endif // SOC_PCNT_SUPPORT_CLEAR_SIGNAL
esp_err_t pcnt_unit_set_glitch_filter(pcnt_unit_handle_t unit, const pcnt_glitch_filter_config_t *config)
{
pcnt_group_t *group = NULL;
uint32_t glitch_filter_thres = 0;
ESP_RETURN_ON_FALSE(unit, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
// glitch filter should be set only when unit is in init state
ESP_RETURN_ON_FALSE(unit->fsm == PCNT_UNIT_FSM_INIT, ESP_ERR_INVALID_STATE, TAG, "unit not in init state");
group = unit->group;
if (config) {
glitch_filter_thres = esp_clk_apb_freq() / 1000000 * config->max_glitch_ns / 1000;
ESP_RETURN_ON_FALSE(glitch_filter_thres <= PCNT_LL_MAX_GLITCH_WIDTH, ESP_ERR_INVALID_ARG, TAG, "glitch width out of range");
// The filter module is working against APB clock, so lazy install PM lock
#if CONFIG_PM_ENABLE
if (!unit->pm_lock) {
sprintf(unit->pm_lock_name, "pcnt_%d_%d", group->group_id, unit->unit_id); // e.g. pcnt_0_0
ESP_RETURN_ON_ERROR(esp_pm_lock_create(ESP_PM_APB_FREQ_MAX, 0, unit->pm_lock_name, &unit->pm_lock), TAG, "install pm lock failed");
ESP_LOGD(TAG, "install APB_FREQ_MAX lock for unit (%d,%d)", group->group_id, unit->unit_id);
}
#endif
}
// filter control bit is mixed with other PCNT control bits in the same register
portENTER_CRITICAL(&unit->spinlock);
if (config) {
pcnt_ll_set_glitch_filter_thres(group->hal.dev, unit->unit_id, glitch_filter_thres);
pcnt_ll_enable_glitch_filter(group->hal.dev, unit->unit_id, true);
} else {
pcnt_ll_enable_glitch_filter(group->hal.dev, unit->unit_id, false);
}
portEXIT_CRITICAL(&unit->spinlock);
return ESP_OK;
}
esp_err_t pcnt_unit_enable(pcnt_unit_handle_t unit)
{
ESP_RETURN_ON_FALSE(unit, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
ESP_RETURN_ON_FALSE(unit->fsm == PCNT_UNIT_FSM_INIT, ESP_ERR_INVALID_STATE, TAG, "unit not in init state");
// acquire power manager lock
if (unit->pm_lock) {
ESP_RETURN_ON_ERROR(esp_pm_lock_acquire(unit->pm_lock), TAG, "acquire pm_lock failed");
}
// enable interrupt service
if (unit->intr) {
ESP_RETURN_ON_ERROR(esp_intr_enable(unit->intr), TAG, "enable interrupt service failed");
}
unit->fsm = PCNT_UNIT_FSM_ENABLE;
return ESP_OK;
}
esp_err_t pcnt_unit_disable(pcnt_unit_handle_t unit)
{
ESP_RETURN_ON_FALSE(unit, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
ESP_RETURN_ON_FALSE(unit->fsm == PCNT_UNIT_FSM_ENABLE, ESP_ERR_INVALID_STATE, TAG, "unit not in enable state");
// disable interrupt service
if (unit->intr) {
ESP_RETURN_ON_ERROR(esp_intr_disable(unit->intr), TAG, "disable interrupt service failed");
}
// release power manager lock
if (unit->pm_lock) {
ESP_RETURN_ON_ERROR(esp_pm_lock_release(unit->pm_lock), TAG, "release APB_FREQ_MAX lock failed");
}
unit->fsm = PCNT_UNIT_FSM_INIT;
return ESP_OK;
}
esp_err_t pcnt_unit_start(pcnt_unit_handle_t unit)
{
ESP_RETURN_ON_FALSE_ISR(unit, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
ESP_RETURN_ON_FALSE_ISR(unit->fsm == PCNT_UNIT_FSM_ENABLE, ESP_ERR_INVALID_STATE, TAG, "unit not enabled yet");
pcnt_group_t *group = unit->group;
// all PCNT units share the same register to control counter
portENTER_CRITICAL_SAFE(&group->spinlock);
pcnt_ll_start_count(group->hal.dev, unit->unit_id);
portEXIT_CRITICAL_SAFE(&group->spinlock);
return ESP_OK;
}
esp_err_t pcnt_unit_stop(pcnt_unit_handle_t unit)
{
ESP_RETURN_ON_FALSE_ISR(unit, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
ESP_RETURN_ON_FALSE_ISR(unit->fsm == PCNT_UNIT_FSM_ENABLE, ESP_ERR_INVALID_STATE, TAG, "unit not enabled yet");
pcnt_group_t *group = unit->group;
// all PCNT units share the same register to control counter
portENTER_CRITICAL_SAFE(&group->spinlock);
pcnt_ll_stop_count(group->hal.dev, unit->unit_id);
portEXIT_CRITICAL_SAFE(&group->spinlock);
return ESP_OK;
}
esp_err_t pcnt_unit_clear_count(pcnt_unit_handle_t unit)
{
pcnt_group_t *group = NULL;
ESP_RETURN_ON_FALSE_ISR(unit, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
group = unit->group;
// all PCNT units share the same register to control counter
portENTER_CRITICAL_SAFE(&group->spinlock);
pcnt_ll_clear_count(group->hal.dev, unit->unit_id);
portEXIT_CRITICAL_SAFE(&group->spinlock);
// reset the accumulated count as well
portENTER_CRITICAL_SAFE(&unit->spinlock);
unit->accum_value = 0;
portEXIT_CRITICAL_SAFE(&unit->spinlock);
return ESP_OK;
}
esp_err_t pcnt_unit_get_count(pcnt_unit_handle_t unit, int *value)
{
pcnt_group_t *group = NULL;
ESP_RETURN_ON_FALSE_ISR(unit && value, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
group = unit->group;
// the accum_value is also accessed by the ISR, so adding a critical section
portENTER_CRITICAL_SAFE(&unit->spinlock);
*value = pcnt_ll_get_count(group->hal.dev, unit->unit_id) + unit->accum_value;
portEXIT_CRITICAL_SAFE(&unit->spinlock);
return ESP_OK;
}
esp_err_t pcnt_unit_register_event_callbacks(pcnt_unit_handle_t unit, const pcnt_event_callbacks_t *cbs, void *user_data)
{
ESP_RETURN_ON_FALSE(unit && cbs, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
// unit event callbacks should be registered in init state
pcnt_group_t *group = unit->group;
int group_id = group->group_id;
int unit_id = unit->unit_id;
#if CONFIG_PCNT_ISR_IRAM_SAFE
if (cbs->on_reach) {
ESP_RETURN_ON_FALSE(esp_ptr_in_iram(cbs->on_reach), ESP_ERR_INVALID_ARG, TAG, "on_reach callback not in IRAM");
}
if (user_data) {
ESP_RETURN_ON_FALSE(esp_ptr_internal(user_data), ESP_ERR_INVALID_ARG, TAG, "user context not in internal RAM");
}
#endif
// lazy install interrupt service
if (!unit->intr) {
ESP_RETURN_ON_FALSE(unit->fsm == PCNT_UNIT_FSM_INIT, ESP_ERR_INVALID_STATE, TAG, "unit not in init state");
int isr_flags = PCNT_INTR_ALLOC_FLAGS;
if (group->intr_priority) {
isr_flags |= 1 << (group->intr_priority);
} else {
isr_flags |= PCNT_ALLOW_INTR_PRIORITY_MASK;
}
ESP_RETURN_ON_ERROR(esp_intr_alloc_intrstatus(pcnt_periph_signals.groups[group_id].irq, isr_flags,
(uint32_t)pcnt_ll_get_intr_status_reg(group->hal.dev), PCNT_LL_UNIT_WATCH_EVENT(unit_id),
pcnt_default_isr, unit, &unit->intr),
TAG, "install interrupt service failed");
}
// enable/disable PCNT interrupt events
portENTER_CRITICAL(&group->spinlock);
pcnt_ll_enable_intr(group->hal.dev, PCNT_LL_UNIT_WATCH_EVENT(unit_id), cbs->on_reach != NULL);
portEXIT_CRITICAL(&group->spinlock);
unit->on_reach = cbs->on_reach;
unit->user_data = user_data;
return ESP_OK;
}
esp_err_t pcnt_unit_add_watch_point(pcnt_unit_handle_t unit, int watch_point)
{
esp_err_t ret = ESP_OK;
pcnt_group_t *group = NULL;
ESP_RETURN_ON_FALSE(unit, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
ESP_RETURN_ON_FALSE(watch_point <= unit->high_limit && watch_point >= unit->low_limit,
ESP_ERR_INVALID_ARG, TAG, "watch_point out of limit");
group = unit->group;
// event enable/disable is mixed with other control function in the same register
portENTER_CRITICAL(&unit->spinlock);
// zero cross watch point
if (watch_point == 0) {
if (unit->watchers[PCNT_LL_WATCH_EVENT_ZERO_CROSS].event_id != PCNT_LL_WATCH_EVENT_INVALID) {
ret = ESP_ERR_INVALID_STATE; // zero cross event watcher has been installed already
} else {
unit->watchers[PCNT_LL_WATCH_EVENT_ZERO_CROSS].event_id = PCNT_LL_WATCH_EVENT_ZERO_CROSS;
unit->watchers[PCNT_LL_WATCH_EVENT_ZERO_CROSS].watch_point_value = 0;
pcnt_ll_enable_zero_cross_event(group->hal.dev, unit->unit_id, true);
}
}
// high limit watch point
else if (watch_point == unit->high_limit) {
if (unit->watchers[PCNT_LL_WATCH_EVENT_HIGH_LIMIT].event_id != PCNT_LL_WATCH_EVENT_INVALID) {
ret = ESP_ERR_INVALID_STATE; // high limit event watcher has been installed already
} else {
unit->watchers[PCNT_LL_WATCH_EVENT_HIGH_LIMIT].event_id = PCNT_LL_WATCH_EVENT_HIGH_LIMIT;
unit->watchers[PCNT_LL_WATCH_EVENT_HIGH_LIMIT].watch_point_value = unit->high_limit;
pcnt_ll_enable_high_limit_event(group->hal.dev, unit->unit_id, true);
}
}
// low limit watch point
else if (watch_point == unit->low_limit) {
if (unit->watchers[PCNT_LL_WATCH_EVENT_LOW_LIMIT].event_id != PCNT_LL_WATCH_EVENT_INVALID) {
ret = ESP_ERR_INVALID_STATE; // low limit event watcher has been installed already
} else {
unit->watchers[PCNT_LL_WATCH_EVENT_LOW_LIMIT].event_id = PCNT_LL_WATCH_EVENT_LOW_LIMIT;
unit->watchers[PCNT_LL_WATCH_EVENT_LOW_LIMIT].watch_point_value = unit->low_limit;
pcnt_ll_enable_low_limit_event(group->hal.dev, unit->unit_id, true);
}
}
// other threshold watch point
else {
int thres_num = SOC_PCNT_THRES_POINT_PER_UNIT - 1;
switch (thres_num) {
case 1:
if (unit->watchers[PCNT_LL_WATCH_EVENT_THRES1].event_id == PCNT_LL_WATCH_EVENT_INVALID) {
unit->watchers[PCNT_LL_WATCH_EVENT_THRES1].event_id = PCNT_LL_WATCH_EVENT_THRES1;
unit->watchers[PCNT_LL_WATCH_EVENT_THRES1].watch_point_value = watch_point;
pcnt_ll_set_thres_value(group->hal.dev, unit->unit_id, 1, watch_point);
pcnt_ll_enable_thres_event(group->hal.dev, unit->unit_id, 1, true);
break;
} else if (unit->watchers[PCNT_LL_WATCH_EVENT_THRES1].watch_point_value == watch_point) {
ret = ESP_ERR_INVALID_STATE;
break;
}
/* fall-through */
case 0:
if (unit->watchers[PCNT_LL_WATCH_EVENT_THRES0].event_id == PCNT_LL_WATCH_EVENT_INVALID) {
unit->watchers[PCNT_LL_WATCH_EVENT_THRES0].event_id = PCNT_LL_WATCH_EVENT_THRES0;
unit->watchers[PCNT_LL_WATCH_EVENT_THRES0].watch_point_value = watch_point;
pcnt_ll_set_thres_value(group->hal.dev, unit->unit_id, 0, watch_point);
pcnt_ll_enable_thres_event(group->hal.dev, unit->unit_id, 0, true);
break;
} else if (unit->watchers[PCNT_LL_WATCH_EVENT_THRES0].watch_point_value == watch_point) {
ret = ESP_ERR_INVALID_STATE;
break;
}
/* fall-through */
default:
ret = ESP_ERR_NOT_FOUND; // no free threshold watch point available
break;
}
}
portEXIT_CRITICAL(&unit->spinlock);
ESP_RETURN_ON_ERROR(ret, TAG, "add watchpoint %d failed", watch_point);
return ESP_OK;
}
esp_err_t pcnt_unit_remove_watch_point(pcnt_unit_handle_t unit, int watch_point)
{
pcnt_group_t *group = NULL;
ESP_RETURN_ON_FALSE(unit, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
group = unit->group;
pcnt_ll_watch_event_id_t event_id = PCNT_LL_WATCH_EVENT_INVALID;
// event enable/disable is mixed with other control function in the same register
portENTER_CRITICAL(&unit->spinlock);
for (int i = 0; i < PCNT_LL_WATCH_EVENT_MAX; i++) {
if (unit->watchers[i].event_id != PCNT_LL_WATCH_EVENT_INVALID && unit->watchers[i].watch_point_value == watch_point) {
event_id = unit->watchers[i].event_id;
unit->watchers[i].event_id = PCNT_LL_WATCH_EVENT_INVALID;
break;
}
}
switch (event_id) {
case PCNT_LL_WATCH_EVENT_ZERO_CROSS:
pcnt_ll_enable_zero_cross_event(group->hal.dev, unit->unit_id, false);
break;
case PCNT_LL_WATCH_EVENT_LOW_LIMIT:
pcnt_ll_enable_low_limit_event(group->hal.dev, unit->unit_id, false);
break;
case PCNT_LL_WATCH_EVENT_HIGH_LIMIT:
pcnt_ll_enable_high_limit_event(group->hal.dev, unit->unit_id, false);
break;
case PCNT_LL_WATCH_EVENT_THRES0:
pcnt_ll_enable_thres_event(group->hal.dev, unit->unit_id, 0, false);
break;
case PCNT_LL_WATCH_EVENT_THRES1:
pcnt_ll_enable_thres_event(group->hal.dev, unit->unit_id, 1, false);
break;
default:
break;
}
portEXIT_CRITICAL(&unit->spinlock);
ESP_RETURN_ON_FALSE(event_id != PCNT_LL_WATCH_EVENT_INVALID, ESP_ERR_INVALID_STATE, TAG, "watch point %d not added yet", watch_point);
return ESP_OK;
}
esp_err_t pcnt_new_channel(pcnt_unit_handle_t unit, const pcnt_chan_config_t *config, pcnt_channel_handle_t *ret_chan)
{
esp_err_t ret = ESP_OK;
pcnt_chan_t *channel = NULL;
pcnt_group_t *group = NULL;
ESP_GOTO_ON_FALSE(unit && config && ret_chan, ESP_ERR_INVALID_ARG, err, TAG, "invalid argument");
ESP_GOTO_ON_FALSE(unit->fsm == PCNT_UNIT_FSM_INIT, ESP_ERR_INVALID_STATE, err, TAG, "unit not in init state");
group = unit->group;
int group_id = group->group_id;
int unit_id = unit->unit_id;
channel = heap_caps_calloc(1, sizeof(pcnt_chan_t), PCNT_MEM_ALLOC_CAPS);
ESP_GOTO_ON_FALSE(channel, ESP_ERR_NO_MEM, err, TAG, "no mem for channel");
// search for a free channel
int channel_id = -1;
portENTER_CRITICAL(&unit->spinlock);
for (int i = 0; i < SOC_PCNT_CHANNELS_PER_UNIT; i++) {
if (!unit->channels[i]) {
channel_id = i;
unit->channels[channel_id] = channel;
break;
}
}
portEXIT_CRITICAL(&unit->spinlock);
ESP_GOTO_ON_FALSE(channel_id != -1, ESP_ERR_NOT_FOUND, err, TAG, "no free channel in unit (%d,%d)", group_id, unit_id);
// GPIO configuration
gpio_config_t gpio_conf = {
.intr_type = GPIO_INTR_DISABLE,
.mode = GPIO_MODE_INPUT | (config->flags.io_loop_back ? GPIO_MODE_OUTPUT : 0), // also enable the output path if `io_loop_back` is enabled
.pull_down_en = false,
.pull_up_en = true,
};
if (config->edge_gpio_num >= 0) {
gpio_conf.pin_bit_mask = 1ULL << config->edge_gpio_num;
ESP_GOTO_ON_ERROR(gpio_config(&gpio_conf), err, TAG, "config edge GPIO failed");
esp_rom_gpio_connect_in_signal(config->edge_gpio_num,
pcnt_periph_signals.groups[group_id].units[unit_id].channels[channel_id].pulse_sig,
config->flags.invert_edge_input);
} else {
// using virtual IO
esp_rom_gpio_connect_in_signal(config->flags.virt_edge_io_level ? GPIO_MATRIX_CONST_ONE_INPUT : GPIO_MATRIX_CONST_ZERO_INPUT,
pcnt_periph_signals.groups[group_id].units[unit_id].channels[channel_id].pulse_sig,
config->flags.invert_edge_input);
}
if (config->level_gpio_num >= 0) {
gpio_conf.pin_bit_mask = 1ULL << config->level_gpio_num;
ESP_GOTO_ON_ERROR(gpio_config(&gpio_conf), err, TAG, "config level GPIO failed");
esp_rom_gpio_connect_in_signal(config->level_gpio_num,
pcnt_periph_signals.groups[group_id].units[unit_id].channels[channel_id].control_sig,
config->flags.invert_level_input);
} else {
// using virtual IO
esp_rom_gpio_connect_in_signal(config->flags.virt_level_io_level ? GPIO_MATRIX_CONST_ONE_INPUT : GPIO_MATRIX_CONST_ZERO_INPUT,
pcnt_periph_signals.groups[group_id].units[unit_id].channels[channel_id].control_sig,
config->flags.invert_level_input);
}
channel->channel_id = channel_id;
channel->unit = unit;
channel->edge_gpio_num = config->edge_gpio_num;
channel->level_gpio_num = config->level_gpio_num;
ESP_LOGD(TAG, "new pcnt channel(%d,%d,%d) at %p", group_id, unit_id, channel_id, channel);
*ret_chan = channel;
return ESP_OK;
err:
if (channel) {
free(channel);
}
return ret;
}
esp_err_t pcnt_del_channel(pcnt_channel_handle_t chan)
{
ESP_RETURN_ON_FALSE(chan, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
pcnt_unit_t *unit = chan->unit;
pcnt_group_t *group = unit->group;
int group_id = group->group_id;
int unit_id = unit->unit_id;
int channel_id = chan->channel_id;
portENTER_CRITICAL(&unit->spinlock);
unit->channels[channel_id] = NULL;
portEXIT_CRITICAL(&unit->spinlock);
if (chan->level_gpio_num >= 0) {
gpio_reset_pin(chan->level_gpio_num);
}
if (chan->edge_gpio_num >= 0) {
gpio_reset_pin(chan->edge_gpio_num);
}
free(chan);
ESP_LOGD(TAG, "del pcnt channel(%d,%d,%d)", group_id, unit_id, channel_id);
return ESP_OK;
}
esp_err_t pcnt_channel_set_edge_action(pcnt_channel_handle_t chan, pcnt_channel_edge_action_t pos_act, pcnt_channel_edge_action_t neg_act)
{
pcnt_group_t *group = NULL;
ESP_RETURN_ON_FALSE(chan, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
pcnt_unit_t *unit = chan->unit;
group = unit->group;
// mode control bits are mixed with other PCNT control bits in a same register
portENTER_CRITICAL(&unit->spinlock);
pcnt_ll_set_edge_action(group->hal.dev, unit->unit_id, chan->channel_id, pos_act, neg_act);
portEXIT_CRITICAL(&unit->spinlock);
return ESP_OK;
}
esp_err_t pcnt_channel_set_level_action(pcnt_channel_handle_t chan, pcnt_channel_level_action_t high_act, pcnt_channel_level_action_t low_act)
{
pcnt_group_t *group = NULL;
ESP_RETURN_ON_FALSE(chan, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
pcnt_unit_t *unit = chan->unit;
group = unit->group;
// mode control bits are mixed with other PCNT control bits in a same register
portENTER_CRITICAL(&unit->spinlock);
pcnt_ll_set_level_action(group->hal.dev, unit->unit_id, chan->channel_id, high_act, low_act);
portEXIT_CRITICAL(&unit->spinlock);
return ESP_OK;
}
static pcnt_group_t *pcnt_acquire_group_handle(int group_id)
{
bool new_group = false;
pcnt_group_t *group = NULL;
// prevent install pcnt group concurrently
_lock_acquire(&s_platform.mutex);
if (!s_platform.groups[group_id]) {
group = heap_caps_calloc(1, sizeof(pcnt_group_t), PCNT_MEM_ALLOC_CAPS);
if (group) {
new_group = true;
s_platform.groups[group_id] = group; // register to platform
// initialize pcnt group members
group->group_id = group_id;
group->intr_priority = -1;
group->spinlock = (portMUX_TYPE)portMUX_INITIALIZER_UNLOCKED;
// enable APB access pcnt registers
PCNT_RCC_ATOMIC() {
pcnt_ll_enable_bus_clock(group_id, true);
pcnt_ll_reset_register(group_id);
}
// initialize HAL context
pcnt_hal_init(&group->hal, group_id);
}
} else {
group = s_platform.groups[group_id];
}
if (group) {
// someone acquired the group handle means we have a new object that refer to this group
s_platform.group_ref_counts[group_id]++;
}
_lock_release(&s_platform.mutex);
if (new_group) {
ESP_LOGD(TAG, "new group (%d) at %p", group_id, group);
}
return group;
}
static void pcnt_release_group_handle(pcnt_group_t *group)
{
int group_id = group->group_id;
bool do_deinitialize = false;
_lock_acquire(&s_platform.mutex);
s_platform.group_ref_counts[group_id]--;
if (s_platform.group_ref_counts[group_id] == 0) {
assert(s_platform.groups[group_id]);
do_deinitialize = true;
s_platform.groups[group_id] = NULL; // deregister from platform
PCNT_RCC_ATOMIC() {
pcnt_ll_enable_bus_clock(group_id, false);
}
}
_lock_release(&s_platform.mutex);
if (do_deinitialize) {
free(group);
ESP_LOGD(TAG, "del group (%d)", group_id);
}
}
IRAM_ATTR static void pcnt_default_isr(void *args)
{
bool need_yield = false;
pcnt_unit_t *unit = (pcnt_unit_t *)args;
int unit_id = unit->unit_id;
pcnt_group_t *group = unit->group;
pcnt_watch_cb_t on_reach = unit->on_reach;
uint32_t intr_status = pcnt_ll_get_intr_status(group->hal.dev);
if (intr_status & PCNT_LL_UNIT_WATCH_EVENT(unit_id)) {
pcnt_ll_clear_intr_status(group->hal.dev, PCNT_LL_UNIT_WATCH_EVENT(unit_id));
// points watcher event
uint32_t event_status = pcnt_ll_get_event_status(group->hal.dev, unit_id);
// iter on each event_id
while (event_status) {
int event_id = __builtin_ffs(event_status) - 1;
event_status &= (event_status - 1); // clear the right most bit
portENTER_CRITICAL_ISR(&unit->spinlock);
if (unit->flags.accum_count) {
if (event_id == PCNT_LL_WATCH_EVENT_LOW_LIMIT) {
unit->accum_value += unit->low_limit;
} else if (event_id == PCNT_LL_WATCH_EVENT_HIGH_LIMIT) {
unit->accum_value += unit->high_limit;
}
}
portEXIT_CRITICAL_ISR(&unit->spinlock);
// invoked user registered callback
if (on_reach) {
pcnt_watch_event_data_t edata = {
.watch_point_value = unit->watchers[event_id].watch_point_value,
.zero_cross_mode = pcnt_ll_get_zero_cross_mode(group->hal.dev, unit_id),
};
if (on_reach(unit, &edata, unit->user_data)) {
// check if we need to yield for high priority task
need_yield = true;
}
}
}
}
if (need_yield) {
portYIELD_FROM_ISR();
}
}