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

137 lines
3.8 KiB
C

/*
* 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 <stdio.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <arch/chip/timer.h>
#include "py/runtime.h"
#include "shared-bindings/pulseio/PulseOut.h"
static uint16_t *pulse_buffer = NULL;
static uint16_t pulse_index = 0;
static uint16_t pulse_length;
static int pulse_fd = -1;
static bool pulseout_timer_handler(uint32_t *next_interval_us, void *arg) {
uint8_t pwm_num = (uint8_t)(int)arg;
pulse_index++;
if (pulse_index >= pulse_length) {
return false;
}
*next_interval_us = pulse_buffer[pulse_index];
if (pulse_index % 2 == 0) {
pwmout_start(pwm_num);
} else {
pwmout_stop(pwm_num);
}
return true;
}
void common_hal_pulseio_pulseout_construct(pulseio_pulseout_obj_t *self,
const mcu_pin_obj_t *pin,
uint32_t frequency,
uint16_t duty_cycle) {
pwmout_result_t result = common_hal_pwmio_pwmout_construct(
&self->pwmout, pin, duty_cycle, frequency, false);
// This will raise an exception and not return if needed.
common_hal_pwmio_pwmout_raise_error(result);
if (pulse_fd < 0) {
pulse_fd = open("/dev/timer0", O_RDONLY);
}
if (pulse_fd < 0) {
mp_raise_RuntimeError(MP_ERROR_TEXT("All timers in use"));
}
self->pwm_num = self->pwmout.number;
}
void common_hal_pulseio_pulseout_deinit(pulseio_pulseout_obj_t *self) {
if (common_hal_pulseio_pulseout_deinited(self)) {
return;
}
ioctl(pulse_fd, TCIOC_STOP, 0);
close(pulse_fd);
pulse_fd = -1;
common_hal_pwmio_pwmout_deinit(&self->pwmout);
pulse_buffer = NULL;
}
bool common_hal_pulseio_pulseout_deinited(pulseio_pulseout_obj_t *self) {
return pulse_fd < 0;
}
void common_hal_pulseio_pulseout_send(pulseio_pulseout_obj_t *self, uint16_t *pulses, uint16_t len) {
if (pulse_buffer != NULL) {
mp_raise_RuntimeError(MP_ERROR_TEXT("Another send is already active"));
}
struct timer_sethandler_s sethandler;
pulse_buffer = pulses;
pulse_index = 0;
pulse_length = len;
unsigned long timeout = pulse_buffer[0];
ioctl(pulse_fd, TCIOC_SETTIMEOUT, timeout);
sethandler.handler = pulseout_timer_handler;
sethandler.arg = (void *)(int)self->pwm_num;
ioctl(pulse_fd, TCIOC_SETHANDLER, (unsigned long)&sethandler);
ioctl(pulse_fd, TCIOC_START, 0);
while (pulse_index < len) {
// Do other things while we wait. The interrupts will handle sending the
// signal.
RUN_BACKGROUND_TASKS;
}
pulse_buffer = NULL;
}
void pulseout_reset(void) {
ioctl(pulse_fd, TCIOC_STOP, 0);
close(pulse_fd);
pulse_fd = -1;
pulse_buffer = NULL;
}