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circuitpython/ports/cxd56/common-hal/pulseio/PulseIn.c

195 lines
6.1 KiB

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright 2019 Sony Semiconductor Solutions Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <arch/board/board.h>
#include "py/runtime.h"
#include "py/mphal.h"
#include "shared-bindings/pulseio/PulseIn.h"
#include "shared-bindings/microcontroller/__init__.h"
static pulseio_pulsein_obj_t *pulsein_objects[12];
static int pulsein_interrupt_handler(int irq, FAR void *context, FAR void *arg);
static int pulsein_set_config(pulseio_pulsein_obj_t *self, bool first_edge) {
int mode;
if (!first_edge) {
mode = INT_BOTH_EDGE;
} else if (self->idle_state) {
mode = INT_FALLING_EDGE;
} else {
mode = INT_RISING_EDGE;
}
return board_gpio_intconfig(self->pin->number, mode, false, pulsein_interrupt_handler);
}
static int pulsein_interrupt_handler(int irq, FAR void *context, FAR void *arg) {
// Grab the current time first.
uint32_t current_us = mp_hal_ticks_us();
pulseio_pulsein_obj_t *self = pulsein_objects[irq - CXD56_IRQ_EXDEVICE_0];
if (self->first_edge) {
self->first_edge = false;
pulsein_set_config(self, false);
board_gpio_int(self->pin->number, true);
} else {
uint32_t us_diff = current_us - self->last_us;
uint16_t duration = 0xffff;
if (us_diff < duration) {
duration = us_diff;
}
uint16_t i = (self->start + self->len) % self->maxlen;
self->buffer[i] = duration;
if (self->len < self->maxlen) {
self->len++;
} else {
self->start++;
}
}
self->last_us = current_us;
return 0;
}
void common_hal_pulseio_pulsein_construct(pulseio_pulsein_obj_t *self,
const mcu_pin_obj_t *pin, uint16_t maxlen, bool idle_state) {
self->buffer = (uint16_t *) m_malloc(maxlen * sizeof(uint16_t), false);
if (self->buffer == NULL) {
mp_raise_msg_varg(&mp_type_MemoryError, translate("Failed to allocate RX buffer of %d bytes"), maxlen * sizeof(uint16_t));
}
self->pin = pin;
self->maxlen = maxlen;
self->idle_state = idle_state;
self->start = 0;
self->len = 0;
self->first_edge = true;
self->paused = false;
int irq = pulsein_set_config(self, true);
if (irq < 0) {
mp_raise_RuntimeError(translate("EXTINT channel already in use"));
} else {
pulsein_objects[irq - CXD56_IRQ_EXDEVICE_0] = self;
}
claim_pin(pin);
board_gpio_int(self->pin->number, true);
}
void common_hal_pulseio_pulsein_deinit(pulseio_pulsein_obj_t *self) {
if (common_hal_pulseio_pulsein_deinited(self)) {
return;
}
board_gpio_int(self->pin->number, false);
board_gpio_intconfig(self->pin->number, 0, false, NULL);
reset_pin_number(self->pin->number);
self->pin = NULL;
}
bool common_hal_pulseio_pulsein_deinited(pulseio_pulsein_obj_t *self) {
return self->pin == NULL;
}
void common_hal_pulseio_pulsein_pause(pulseio_pulsein_obj_t *self) {
board_gpio_int(self->pin->number, false);
self->paused = true;
}
void common_hal_pulseio_pulsein_resume(pulseio_pulsein_obj_t *self, uint16_t trigger_duration) {
// Make sure we're paused.
common_hal_pulseio_pulsein_pause(self);
// Send the trigger pulse.
if (trigger_duration > 0) {
board_gpio_config(self->pin->number, 0, false, true, PIN_FLOAT);
board_gpio_write(self->pin->number, !self->idle_state);
common_hal_mcu_delay_us((uint32_t)trigger_duration);
board_gpio_write(self->pin->number, self->idle_state);
}
// Reconfigure the pin and make sure its set to detect the first edge.
self->first_edge = true;
self->paused = false;
pulsein_set_config(self, true);
board_gpio_int(self->pin->number, true);
}
void common_hal_pulseio_pulsein_clear(pulseio_pulsein_obj_t *self) {
common_hal_mcu_disable_interrupts();
self->start = 0;
self->len = 0;
common_hal_mcu_enable_interrupts();
}
uint16_t common_hal_pulseio_pulsein_popleft(pulseio_pulsein_obj_t *self) {
if (self->len == 0) {
mp_raise_IndexError(translate("pop from an empty PulseIn"));
}
common_hal_mcu_disable_interrupts();
uint16_t value = self->buffer[self->start];
self->start = (self->start + 1) % self->maxlen;
self->len--;
common_hal_mcu_enable_interrupts();
return value;
}
uint16_t common_hal_pulseio_pulsein_get_maxlen(pulseio_pulsein_obj_t *self) {
return self->maxlen;
}
bool common_hal_pulseio_pulsein_get_paused(pulseio_pulsein_obj_t *self) {
return self->paused;
}
uint16_t common_hal_pulseio_pulsein_get_len(pulseio_pulsein_obj_t *self) {
return self->len;
}
uint16_t common_hal_pulseio_pulsein_get_item(pulseio_pulsein_obj_t *self, int16_t index) {
common_hal_mcu_disable_interrupts();
if (index < 0) {
index += self->len;
}
if (index < 0 || index >= self->len) {
common_hal_mcu_enable_interrupts();
mp_raise_IndexError(translate("index out of range"));
}
uint16_t value = self->buffer[(self->start + index) % self->maxlen];
common_hal_mcu_enable_interrupts();
return value;
}