circuitpython/shared-module/adafruit_bus_device/SPIDevice.c

87 lines
3.2 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/SPIDevice.h"
#include "shared-bindings/busio/SPI.h"
#include "shared-bindings/digitalio/DigitalInOut.h"
#include "py/mperrno.h"
#include "py/nlr.h"
#include "py/runtime.h"
void common_hal_adafruit_bus_device_spidevice_construct(adafruit_bus_device_spidevice_obj_t *self, busio_spi_obj_t *spi, digitalio_digitalinout_obj_t *cs,
uint32_t baudrate, uint8_t polarity, uint8_t phase, uint8_t extra_clocks) {
self->spi = spi;
self->baudrate = baudrate;
self->polarity = polarity;
self->phase = phase;
self->extra_clocks = extra_clocks;
self->chip_select = cs;
}
mp_obj_t common_hal_adafruit_bus_device_spidevice_enter(adafruit_bus_device_spidevice_obj_t *self) {
bool success = false;
while (!success) {
success = common_hal_busio_spi_try_lock(self->spi);
RUN_BACKGROUND_TASKS;
mp_handle_pending();
}
common_hal_busio_spi_configure(self->spi, self->baudrate, self->polarity, self->phase, 8);
if (self->chip_select != MP_OBJ_NULL) {
common_hal_digitalio_digitalinout_set_value(MP_OBJ_TO_PTR(self->chip_select), false);
}
return self->spi;
}
void common_hal_adafruit_bus_device_spidevice_exit(adafruit_bus_device_spidevice_obj_t *self) {
if (self->chip_select != MP_OBJ_NULL) {
common_hal_digitalio_digitalinout_set_value(MP_OBJ_TO_PTR(self->chip_select), true);
}
if (self->extra_clocks > 0) {
mp_buffer_info_t bufinfo;
mp_obj_t buffer = mp_obj_new_bytearray_of_zeros(1);
mp_get_buffer_raise(buffer, &bufinfo, MP_BUFFER_READ);
((uint8_t*)bufinfo.buf)[0] = 0xFF;
uint8_t clocks = self->extra_clocks / 8;
if ((self->extra_clocks % 8) != 0)
clocks += 1;
while (clocks > 0) {
if (!common_hal_busio_spi_write(self->spi, ((uint8_t*)bufinfo.buf), 1)) {
mp_raise_OSError(MP_EIO);
}
clocks--;
}
}
common_hal_busio_spi_unlock(self->spi);
}