circuitpython/shared-module/adafruit_bus_device/i2c_device/I2CDevice.c

91 lines
3.4 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2020 Mark Komus
*
* 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/adafruit_bus_device/i2c_device/I2CDevice.h"
#include "shared-bindings/busio/I2C.h"
#include "py/mperrno.h"
#include "py/nlr.h"
#include "py/runtime.h"
#include "shared/runtime/interrupt_char.h"
void common_hal_adafruit_bus_device_i2cdevice_construct(adafruit_bus_device_i2cdevice_obj_t *self, mp_obj_t *i2c, uint8_t device_address) {
self->i2c = i2c;
self->device_address = device_address;
}
void common_hal_adafruit_bus_device_i2cdevice_lock(adafruit_bus_device_i2cdevice_obj_t *self) {
mp_obj_t dest[2];
mp_load_method(self->i2c, MP_QSTR_try_lock, dest);
mp_obj_t success = mp_call_method_n_kw(0, 0, dest);
while (!mp_obj_is_true(success)) {
RUN_BACKGROUND_TASKS;
if (mp_hal_is_interrupted()) {
break;
}
success = mp_call_method_n_kw(0, 0, dest);
}
}
void common_hal_adafruit_bus_device_i2cdevice_unlock(adafruit_bus_device_i2cdevice_obj_t *self) {
mp_obj_t dest[2];
mp_load_method(self->i2c, MP_QSTR_unlock, dest);
mp_call_method_n_kw(0, 0, dest);
}
void common_hal_adafruit_bus_device_i2cdevice_probe_for_device(adafruit_bus_device_i2cdevice_obj_t *self) {
common_hal_adafruit_bus_device_i2cdevice_lock(self);
mp_buffer_info_t write_bufinfo;
mp_obj_t write_buffer = mp_obj_new_bytearray_of_zeros(0);
mp_get_buffer_raise(write_buffer, &write_bufinfo, MP_BUFFER_READ);
mp_obj_t dest[4];
/* catch exceptions that may be thrown while probing for the device */
nlr_buf_t nlr;
if (nlr_push(&nlr) == 0) {
mp_load_method(self->i2c, MP_QSTR_writeto, dest);
dest[2] = MP_OBJ_NEW_SMALL_INT(self->device_address);
dest[3] = write_buffer;
mp_call_method_n_kw(2, 0, dest);
nlr_pop();
} else {
common_hal_adafruit_bus_device_i2cdevice_unlock(self);
if (mp_obj_is_subclass_fast(MP_OBJ_FROM_PTR(((mp_obj_base_t *)nlr.ret_val)->type), MP_OBJ_FROM_PTR(&mp_type_OSError))) {
mp_raise_ValueError_varg(MP_ERROR_TEXT("No I2C device at address: 0x%x"), self->device_address);
} else {
/* In case we receive an unrelated exception pass it up */
nlr_raise(MP_OBJ_FROM_PTR(nlr.ret_val));
}
}
common_hal_adafruit_bus_device_i2cdevice_unlock(self);
}