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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2021 Scott Shawcroft for Adafruit Industries
*
* 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/busio/I2C.h"
#include "py/mperrno.h"
#include "py/runtime.h"
#include "shared-bindings/microcontroller/__init__.h"
#include "supervisor/shared/translate.h"
#include "src/rp2_common/hardware_gpio/include/hardware/gpio.h"
// Synopsys DW_apb_i2c (v2.01) IP
#define NO_PIN 0xff
STATIC bool never_reset_i2c[2];
STATIC i2c_inst_t* i2c[2] = {i2c0, i2c1};
void reset_i2c(void) {
for (size_t i = 0; i < 2; i++) {
if (never_reset_i2c[i]) {
continue;
}
i2c_deinit(i2c[i]);
}
}
void common_hal_busio_i2c_construct(busio_i2c_obj_t *self,
const mcu_pin_obj_t* scl, const mcu_pin_obj_t* sda, uint32_t frequency, uint32_t timeout) {
self->peripheral = NULL;
// I2C pins have a regular pattern. SCL is always odd and SDA is even. They match up in pairs
// so we can divide by two to get the instance. This pattern repeats.
if (scl->number % 2 == 1 && sda->number % 2 == 0 && scl->number / 2 == sda->number / 2) {
size_t instance = (scl->number / 2) % 2;
self->peripheral = i2c[instance];
}
if (self->peripheral == NULL) {
mp_raise_ValueError(translate("Invalid pins"));
}
if ((i2c_get_hw(self->peripheral)->enable & I2C_IC_ENABLE_ENABLE_BITS) != 0) {
mp_raise_ValueError(translate("I2C peripheral in use"));
}
if (frequency > 1000000) {
mp_raise_ValueError(translate("Unsupported baudrate"));
}
#if CIRCUITPY_REQUIRE_I2C_PULLUPS
// Test that the pins are in a high state. (Hopefully indicating they are pulled up.)
gpio_set_function(sda->number, GPIO_FUNC_SIO);
gpio_set_function(scl->number, GPIO_FUNC_SIO);
gpio_set_dir(sda->number, GPIO_IN);
gpio_set_dir(scl->number, GPIO_IN);
gpio_set_pulls(sda->number, false, true);
gpio_set_pulls(scl->number, false, true);
common_hal_mcu_delay_us(10);
gpio_set_pulls(sda->number, false, false);
gpio_set_pulls(scl->number, false, false);
// We must pull up within 3us to achieve 400khz.
common_hal_mcu_delay_us(3);
if (!gpio_get(sda->number) || !gpio_get(scl->number)) {
reset_pin_number(sda->number);
reset_pin_number(scl->number);
mp_raise_RuntimeError(translate("No pull up found on SDA or SCL; check your wiring"));
}
#endif
gpio_set_function(sda->number, GPIO_FUNC_I2C);
gpio_set_function(scl->number, GPIO_FUNC_I2C);
self->baudrate = i2c_init(self->peripheral, frequency);
self->sda_pin = sda->number;
self->scl_pin = scl->number;
claim_pin(sda);
claim_pin(scl);
}
bool common_hal_busio_i2c_deinited(busio_i2c_obj_t *self) {
return self->sda_pin == NO_PIN;
}
void common_hal_busio_i2c_deinit(busio_i2c_obj_t *self) {
if (common_hal_busio_i2c_deinited(self)) {
return;
}
never_reset_i2c[i2c_hw_index(self->peripheral)] = false;
i2c_deinit(self->peripheral);
reset_pin_number(self->sda_pin);
reset_pin_number(self->scl_pin);
self->sda_pin = NO_PIN;
self->scl_pin = NO_PIN;
}
bool common_hal_busio_i2c_probe(busio_i2c_obj_t *self, uint8_t addr) {
uint8_t fake_read = 0;
return i2c_read_blocking(self->peripheral, addr, &fake_read, 1, false) != PICO_ERROR_GENERIC;
}
bool common_hal_busio_i2c_try_lock(busio_i2c_obj_t *self) {
bool grabbed_lock = false;
if (!self->has_lock) {
grabbed_lock = true;
self->has_lock = true;
}
return grabbed_lock;
}
bool common_hal_busio_i2c_has_lock(busio_i2c_obj_t *self) {
return self->has_lock;
}
void common_hal_busio_i2c_unlock(busio_i2c_obj_t *self) {
self->has_lock = false;
}
uint8_t common_hal_busio_i2c_write(busio_i2c_obj_t *self, uint16_t addr,
const uint8_t *data, size_t len, bool transmit_stop_bit) {
int result = i2c_write_blocking(self->peripheral, addr, data, len, !transmit_stop_bit);
if (result == len) {
return 0;
} else if (result == PICO_ERROR_GENERIC) {
return MP_ENODEV;
}
return MP_EIO;
}
uint8_t common_hal_busio_i2c_read(busio_i2c_obj_t *self, uint16_t addr,
uint8_t *data, size_t len) {
int result = i2c_read_blocking(self->peripheral, addr, data, len, false);
if (result == len) {
return 0;
} else if (result == PICO_ERROR_GENERIC) {
return MP_ENODEV;
}
return MP_EIO;
}
void common_hal_busio_i2c_never_reset(busio_i2c_obj_t *self) {
never_reset_i2c[i2c_hw_index(self->peripheral)] = true;
never_reset_pin_number(self->scl_pin);
never_reset_pin_number(self->sda_pin);
}
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