circuitpython/shared-bindings/i2cdisplaybus/I2CDisplayBus.c

138 lines
6.3 KiB
C

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2019 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/i2cdisplaybus/I2CDisplayBus.h"
#include <stdint.h>
#include <string.h>
#include "shared/runtime/context_manager_helpers.h"
#include "py/binary.h"
#include "py/runtime.h"
#include "shared-bindings/microcontroller/Pin.h"
#include "shared-bindings/busio/I2C.h"
#include "shared-bindings/util.h"
#include "shared-module/displayio/__init__.h"
//| class I2CDisplayBus:
//| """Manage updating a display over I2C in the background while Python code runs.
//| It doesn't handle display initialization."""
//|
//| def __init__(
//| self,
//| i2c_bus: busio.I2C,
//| *,
//| device_address: int,
//| reset: Optional[microcontroller.Pin] = None
//| ) -> None:
//| """Create a I2CDisplayBus object associated with the given I2C bus and reset pin.
//|
//| The I2C bus and pins are then in use by the display until `displayio.release_displays()` is
//| called even after a reload. (It does this so CircuitPython can use the display after your code
//| is done.) So, the first time you initialize a display bus in code.py you should call
//| :py:func:`displayio.release_displays` first, otherwise it will error after the first code.py run.
//|
//| :param busio.I2C i2c_bus: The I2C bus that make up the clock and data lines
//| :param int device_address: The I2C address of the device
//| :param microcontroller.Pin reset: Reset pin. When None only software reset can be used
//| """
//| ...
STATIC mp_obj_t i2cdisplaybus_i2cdisplaybus_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
enum { ARG_i2c_bus, ARG_device_address, ARG_reset };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_i2c_bus, MP_ARG_REQUIRED | MP_ARG_OBJ },
{ MP_QSTR_device_address, MP_ARG_INT | MP_ARG_KW_ONLY | MP_ARG_REQUIRED },
{ MP_QSTR_reset, MP_ARG_OBJ | MP_ARG_KW_ONLY, {.u_obj = mp_const_none} },
};
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
const mcu_pin_obj_t *reset = validate_obj_is_free_pin_or_none(args[ARG_reset].u_obj, MP_QSTR_reset);
mp_obj_t i2c = mp_arg_validate_type(args[ARG_i2c_bus].u_obj, &busio_i2c_type, MP_QSTR_i2c_bus);
i2cdisplaybus_i2cdisplaybus_obj_t *self = &allocate_display_bus_or_raise()->i2cdisplay_bus;
self->base.type = &i2cdisplaybus_i2cdisplaybus_type;
common_hal_i2cdisplaybus_i2cdisplaybus_construct(self,
MP_OBJ_TO_PTR(i2c), args[ARG_device_address].u_int, reset);
return self;
}
//| def reset(self) -> None:
//| """Performs a hardware reset via the reset pin. Raises an exception if called when no reset pin
//| is available."""
//| ...
STATIC mp_obj_t i2cdisplaybus_i2cdisplaybus_obj_reset(mp_obj_t self_in) {
i2cdisplaybus_i2cdisplaybus_obj_t *self = self_in;
if (!common_hal_i2cdisplaybus_i2cdisplaybus_reset(self)) {
mp_raise_RuntimeError_varg(MP_ERROR_TEXT("No %q pin"), MP_QSTR_reset);
}
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_1(i2cdisplaybus_i2cdisplaybus_reset_obj, i2cdisplaybus_i2cdisplaybus_obj_reset);
//| def send(self, command: int, data: ReadableBuffer) -> None:
//| """Sends the given command value followed by the full set of data. Display state, such as
//| vertical scroll, set via ``send`` may or may not be reset once the code is done."""
//| ...
//|
STATIC mp_obj_t i2cdisplaybus_i2cdisplaybus_obj_send(mp_obj_t self, mp_obj_t command_obj, mp_obj_t data_obj) {
mp_int_t command_int = mp_obj_get_int(command_obj);
mp_arg_validate_int_range(command_int, 0, 255, MP_QSTR_command);
uint8_t command = command_int;
mp_buffer_info_t bufinfo;
mp_get_buffer_raise(data_obj, &bufinfo, MP_BUFFER_READ);
// Wait for display bus to be available.
while (!common_hal_i2cdisplaybus_i2cdisplaybus_begin_transaction(self)) {
RUN_BACKGROUND_TASKS;
}
uint8_t full_command[bufinfo.len + 1];
full_command[0] = command;
memcpy(full_command + 1, ((uint8_t *)bufinfo.buf), bufinfo.len);
common_hal_i2cdisplaybus_i2cdisplaybus_send(self, DISPLAY_COMMAND, CHIP_SELECT_UNTOUCHED, full_command, bufinfo.len + 1);
common_hal_i2cdisplaybus_i2cdisplaybus_end_transaction(self);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_3(i2cdisplaybus_i2cdisplaybus_send_obj, i2cdisplaybus_i2cdisplaybus_obj_send);
STATIC const mp_rom_map_elem_t i2cdisplaybus_i2cdisplaybus_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_reset), MP_ROM_PTR(&i2cdisplaybus_i2cdisplaybus_reset_obj) },
{ MP_ROM_QSTR(MP_QSTR_send), MP_ROM_PTR(&i2cdisplaybus_i2cdisplaybus_send_obj) },
};
STATIC MP_DEFINE_CONST_DICT(i2cdisplaybus_i2cdisplaybus_locals_dict, i2cdisplaybus_i2cdisplaybus_locals_dict_table);
MP_DEFINE_CONST_OBJ_TYPE(
i2cdisplaybus_i2cdisplaybus_type,
MP_QSTR_I2CDisplayBus,
MP_TYPE_FLAG_NONE,
make_new, i2cdisplaybus_i2cdisplaybus_make_new,
locals_dict, &i2cdisplaybus_i2cdisplaybus_locals_dict
);