micropython/ports/esp32/machine_pwm.c
Damien George 8e048d2548 all: Clean up error strings to use lowercase and change cannot to can't.
Now that error string compression is supported it's more important to have
consistent error string formatting (eg all lowercase English words,
consistent contractions).  This commit cleans up some of the strings to
make them more consistent.
2020-04-13 22:19:37 +10:00

297 lines
9.1 KiB
C

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2016 Damien P. George
*
* 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 "driver/ledc.h"
#include "esp_err.h"
#include "py/nlr.h"
#include "py/runtime.h"
#include "modmachine.h"
#include "mphalport.h"
// Forward dec'l
extern const mp_obj_type_t machine_pwm_type;
typedef struct _esp32_pwm_obj_t {
mp_obj_base_t base;
gpio_num_t pin;
uint8_t active;
uint8_t channel;
} esp32_pwm_obj_t;
// Which channel has which GPIO pin assigned?
// (-1 if not assigned)
STATIC int chan_gpio[LEDC_CHANNEL_MAX];
// Params for PW operation
// 5khz
#define PWFREQ (5000)
// High speed mode
#define PWMODE (LEDC_HIGH_SPEED_MODE)
// 10-bit resolution (compatible with esp8266 PWM)
#define PWRES (LEDC_TIMER_10_BIT)
// Timer 1
#define PWTIMER (LEDC_TIMER_1)
// Config of timer upon which we run all PWM'ed GPIO pins
STATIC bool pwm_inited = false;
STATIC ledc_timer_config_t timer_cfg = {
.duty_resolution = PWRES,
.freq_hz = PWFREQ,
.speed_mode = PWMODE,
.timer_num = PWTIMER
};
STATIC void pwm_init(void) {
// Initial condition: no channels assigned
for (int x = 0; x < LEDC_CHANNEL_MAX; ++x) {
chan_gpio[x] = -1;
}
// Init with default timer params
ledc_timer_config(&timer_cfg);
}
STATIC int set_freq(int newval) {
int ores = timer_cfg.duty_resolution;
int oval = timer_cfg.freq_hz;
// Find the highest bit resolution for the requested frequency
if (newval <= 0) {
newval = 1;
}
unsigned int res = 0;
for (unsigned int i = LEDC_APB_CLK_HZ / newval; i > 1; i >>= 1, ++res) {
}
if (res == 0) {
res = 1;
} else if (res > PWRES) {
// Limit resolution to PWRES to match units of our duty
res = PWRES;
}
// Configure the new resolution and frequency
timer_cfg.duty_resolution = res;
timer_cfg.freq_hz = newval;
if (ledc_timer_config(&timer_cfg) != ESP_OK) {
timer_cfg.duty_resolution = ores;
timer_cfg.freq_hz = oval;
return 0;
}
return 1;
}
/******************************************************************************/
// MicroPython bindings for PWM
STATIC void esp32_pwm_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
esp32_pwm_obj_t *self = MP_OBJ_TO_PTR(self_in);
mp_printf(print, "PWM(%u", self->pin);
if (self->active) {
mp_printf(print, ", freq=%u, duty=%u", timer_cfg.freq_hz,
ledc_get_duty(PWMODE, self->channel));
}
mp_printf(print, ")");
}
STATIC void esp32_pwm_init_helper(esp32_pwm_obj_t *self,
size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
enum { ARG_freq, ARG_duty };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_freq, MP_ARG_INT, {.u_int = -1} },
{ MP_QSTR_duty, MP_ARG_INT, {.u_int = -1} },
};
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args, pos_args, kw_args,
MP_ARRAY_SIZE(allowed_args), allowed_args, args);
int channel;
int avail = -1;
// Find a free PWM channel, also spot if our pin is
// already mentioned.
for (channel = 0; channel < LEDC_CHANNEL_MAX; ++channel) {
if (chan_gpio[channel] == self->pin) {
break;
}
if ((avail == -1) && (chan_gpio[channel] == -1)) {
avail = channel;
}
}
if (channel >= LEDC_CHANNEL_MAX) {
if (avail == -1) {
mp_raise_ValueError(MP_ERROR_TEXT("out of PWM channels"));
}
channel = avail;
}
self->channel = channel;
// New PWM assignment
self->active = 1;
if (chan_gpio[channel] == -1) {
ledc_channel_config_t cfg = {
.channel = channel,
.duty = (1 << timer_cfg.duty_resolution) / 2,
.gpio_num = self->pin,
.intr_type = LEDC_INTR_DISABLE,
.speed_mode = PWMODE,
.timer_sel = PWTIMER,
};
if (ledc_channel_config(&cfg) != ESP_OK) {
mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("PWM not supported on pin %d"), self->pin);
}
chan_gpio[channel] = self->pin;
}
// Maybe change PWM timer
int tval = args[ARG_freq].u_int;
if (tval != -1) {
if (tval != timer_cfg.freq_hz) {
if (!set_freq(tval)) {
mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("bad frequency %d"), tval);
}
}
}
// Set duty cycle?
int dval = args[ARG_duty].u_int;
if (dval != -1) {
dval &= ((1 << PWRES) - 1);
dval >>= PWRES - timer_cfg.duty_resolution;
ledc_set_duty(PWMODE, channel, dval);
ledc_update_duty(PWMODE, channel);
}
}
STATIC mp_obj_t esp32_pwm_make_new(const mp_obj_type_t *type,
size_t n_args, size_t n_kw, const mp_obj_t *args) {
mp_arg_check_num(n_args, n_kw, 1, MP_OBJ_FUN_ARGS_MAX, true);
gpio_num_t pin_id = machine_pin_get_id(args[0]);
// create PWM object from the given pin
esp32_pwm_obj_t *self = m_new_obj(esp32_pwm_obj_t);
self->base.type = &machine_pwm_type;
self->pin = pin_id;
self->active = 0;
self->channel = -1;
// start the PWM subsystem if it's not already running
if (!pwm_inited) {
pwm_init();
pwm_inited = true;
}
// start the PWM running for this channel
mp_map_t kw_args;
mp_map_init_fixed_table(&kw_args, n_kw, args + n_args);
esp32_pwm_init_helper(self, n_args - 1, args + 1, &kw_args);
return MP_OBJ_FROM_PTR(self);
}
STATIC mp_obj_t esp32_pwm_init(size_t n_args,
const mp_obj_t *args, mp_map_t *kw_args) {
esp32_pwm_init_helper(args[0], n_args - 1, args + 1, kw_args);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_KW(esp32_pwm_init_obj, 1, esp32_pwm_init);
STATIC mp_obj_t esp32_pwm_deinit(mp_obj_t self_in) {
esp32_pwm_obj_t *self = MP_OBJ_TO_PTR(self_in);
int chan = self->channel;
// Valid channel?
if ((chan >= 0) && (chan < LEDC_CHANNEL_MAX)) {
// Mark it unused, and tell the hardware to stop routing
chan_gpio[chan] = -1;
ledc_stop(PWMODE, chan, 0);
self->active = 0;
self->channel = -1;
gpio_matrix_out(self->pin, SIG_GPIO_OUT_IDX, false, false);
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(esp32_pwm_deinit_obj, esp32_pwm_deinit);
STATIC mp_obj_t esp32_pwm_freq(size_t n_args, const mp_obj_t *args) {
if (n_args == 1) {
// get
return MP_OBJ_NEW_SMALL_INT(timer_cfg.freq_hz);
}
// set
int tval = mp_obj_get_int(args[1]);
if (!set_freq(tval)) {
mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("bad frequency %d"), tval);
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(esp32_pwm_freq_obj, 1, 2, esp32_pwm_freq);
STATIC mp_obj_t esp32_pwm_duty(size_t n_args, const mp_obj_t *args) {
esp32_pwm_obj_t *self = MP_OBJ_TO_PTR(args[0]);
int duty;
if (n_args == 1) {
// get
duty = ledc_get_duty(PWMODE, self->channel);
duty <<= PWRES - timer_cfg.duty_resolution;
return MP_OBJ_NEW_SMALL_INT(duty);
}
// set
duty = mp_obj_get_int(args[1]);
duty &= ((1 << PWRES) - 1);
duty >>= PWRES - timer_cfg.duty_resolution;
ledc_set_duty(PWMODE, self->channel, duty);
ledc_update_duty(PWMODE, self->channel);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(esp32_pwm_duty_obj,
1, 2, esp32_pwm_duty);
STATIC const mp_rom_map_elem_t esp32_pwm_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&esp32_pwm_init_obj) },
{ MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&esp32_pwm_deinit_obj) },
{ MP_ROM_QSTR(MP_QSTR_freq), MP_ROM_PTR(&esp32_pwm_freq_obj) },
{ MP_ROM_QSTR(MP_QSTR_duty), MP_ROM_PTR(&esp32_pwm_duty_obj) },
};
STATIC MP_DEFINE_CONST_DICT(esp32_pwm_locals_dict,
esp32_pwm_locals_dict_table);
const mp_obj_type_t machine_pwm_type = {
{ &mp_type_type },
.name = MP_QSTR_PWM,
.print = esp32_pwm_print,
.make_new = esp32_pwm_make_new,
.locals_dict = (mp_obj_dict_t *)&esp32_pwm_locals_dict,
};