circuitpython/ports/espressif/common-hal/i2ctarget/I2CTarget.c

127 lines
4.2 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2020 microDev
*
* 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 "shared-bindings/i2ctarget/I2CTarget.h"
#include "py/mperrno.h"
#include "py/runtime.h"
#include "common-hal/i2ctarget/I2CTarget.h"
#include "shared-bindings/microcontroller/Pin.h"
void common_hal_i2ctarget_i2c_target_construct(i2ctarget_i2c_target_obj_t *self,
const mcu_pin_obj_t *scl, const mcu_pin_obj_t *sda,
uint8_t *addresses, unsigned int num_addresses, bool smbus) {
// Pins 45 and 46 are "strapping" pins that impact start up behavior. They usually need to
// be pulled-down so pulling them up for I2C is a bad idea. To make this hard, we don't
// support I2C on these pins.
// Also 46 is input-only so it'll never work.
if (scl->number == 45 || scl->number == 46 || sda->number == 45 || sda->number == 46) {
raise_ValueError_invalid_pins();
}
if (num_addresses > 1) {
mp_raise_ValueError(MP_ERROR_TEXT("Only one address is allowed"));
}
self->addresses = addresses;
self->num_addresses = num_addresses;
self->sda_pin = sda;
self->scl_pin = scl;
self->i2c_num = peripherals_i2c_get_free_num();
if (self->i2c_num == I2C_NUM_MAX) {
mp_raise_ValueError(MP_ERROR_TEXT("All I2C peripherals are in use"));
}
const i2c_config_t i2c_conf = {
.mode = I2C_MODE_SLAVE,
.sda_io_num = self->sda_pin->number,
.scl_io_num = self->scl_pin->number,
.sda_pullup_en = GPIO_PULLUP_ENABLE,
.scl_pullup_en = GPIO_PULLUP_ENABLE,
.slave.addr_10bit_en = 0,
.slave.slave_addr = self->addresses[0],
};
// Initialize I2C.
esp_err_t err = peripherals_i2c_init(self->i2c_num, &i2c_conf);
if (err != ESP_OK) {
if (err == ESP_FAIL) {
mp_raise_OSError(MP_EIO);
} else {
mp_arg_error_invalid(MP_QSTR_I2CTarget);
}
}
claim_pin(sda);
claim_pin(scl);
}
bool common_hal_i2ctarget_i2c_target_deinited(i2ctarget_i2c_target_obj_t *self) {
return self->sda_pin == NULL;
}
void common_hal_i2ctarget_i2c_target_deinit(i2ctarget_i2c_target_obj_t *self) {
if (common_hal_i2ctarget_i2c_target_deinited(self)) {
return;
}
peripherals_i2c_deinit(self->i2c_num);
common_hal_reset_pin(self->sda_pin);
common_hal_reset_pin(self->scl_pin);
self->sda_pin = NULL;
self->scl_pin = NULL;
}
int common_hal_i2ctarget_i2c_target_is_addressed(i2ctarget_i2c_target_obj_t *self,
uint8_t *address, bool *is_read, bool *is_restart) {
*address = self->addresses[0];
*is_read = true;
*is_restart = false;
return 1;
}
int common_hal_i2ctarget_i2c_target_read_byte(i2ctarget_i2c_target_obj_t *self, uint8_t *data) {
i2c_slave_read_buffer(self->i2c_num, data, 128, 0);
return 1;
}
int common_hal_i2ctarget_i2c_target_write_byte(i2ctarget_i2c_target_obj_t *self, uint8_t data) {
i2c_reset_tx_fifo(self->i2c_num);
i2c_slave_write_buffer(self->i2c_num, &data, 128, 0);
return 1;
}
void common_hal_i2ctarget_i2c_target_ack(i2ctarget_i2c_target_obj_t *self, bool ack) {
}
void common_hal_i2ctarget_i2c_target_close(i2ctarget_i2c_target_obj_t *self) {
}