/* * This file is part of the MicroPython project, http://micropython.org/ * * The MIT License (MIT) * * Copyright (c) 2016 Scott Shawcroft * * 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. */ // This file contains all of the Python API definitions for the // busio.I2C class. #include "shared-bindings/microcontroller/Pin.h" #include "shared-bindings/busio/I2C.h" #include "shared-bindings/util.h" #include "shared/runtime/buffer_helper.h" #include "shared/runtime/context_manager_helpers.h" #include "py/binary.h" #include "py/runtime.h" //| class I2C: //| """Two wire serial protocol""" //| //| def __init__( //| self, //| scl: microcontroller.Pin, //| sda: microcontroller.Pin, //| *, //| frequency: int = 100000, //| timeout: int = 255 //| ) -> None: //| """I2C is a two-wire protocol for communicating between devices. At the //| physical level it consists of 2 wires: SCL and SDA, the clock and data //| lines respectively. //| //| .. seealso:: Using this class directly requires careful lock management. //| Instead, use :class:`~adafruit_bus_device.I2CDevice` to //| manage locks. //| //| .. seealso:: Using this class to directly read registers requires manual //| bit unpacking. Instead, use an existing driver or make one with //| :ref:`Register ` data descriptors. //| //| :param ~microcontroller.Pin scl: The clock pin //| :param ~microcontroller.Pin sda: The data pin //| :param int frequency: The clock frequency in Hertz //| :param int timeout: The maximum clock stretching timeut - (used only for //| :class:`bitbangio.I2C`; ignored for :class:`busio.I2C`) //| """ //| ... STATIC mp_obj_t busio_i2c_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) { busio_i2c_obj_t *self = mp_obj_malloc(busio_i2c_obj_t, &busio_i2c_type); enum { ARG_scl, ARG_sda, ARG_frequency, ARG_timeout }; static const mp_arg_t allowed_args[] = { { MP_QSTR_scl, MP_ARG_REQUIRED | MP_ARG_OBJ }, { MP_QSTR_sda, MP_ARG_REQUIRED | MP_ARG_OBJ }, { MP_QSTR_frequency, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 100000} }, { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 255} }, }; 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 *scl = validate_obj_is_free_pin(args[ARG_scl].u_obj, MP_QSTR_scl); const mcu_pin_obj_t *sda = validate_obj_is_free_pin(args[ARG_sda].u_obj, MP_QSTR_sda); common_hal_busio_i2c_construct(self, scl, sda, args[ARG_frequency].u_int, args[ARG_timeout].u_int); return (mp_obj_t)self; } //| def deinit(self) -> None: //| """Releases control of the underlying hardware so other classes can use it.""" //| ... STATIC mp_obj_t busio_i2c_obj_deinit(mp_obj_t self_in) { busio_i2c_obj_t *self = MP_OBJ_TO_PTR(self_in); common_hal_busio_i2c_deinit(self); return mp_const_none; } MP_DEFINE_CONST_FUN_OBJ_1(busio_i2c_deinit_obj, busio_i2c_obj_deinit); STATIC void check_for_deinit(busio_i2c_obj_t *self) { if (common_hal_busio_i2c_deinited(self)) { raise_deinited_error(); } } //| def __enter__(self) -> I2C: //| """No-op used in Context Managers.""" //| ... // Provided by context manager helper. //| def __exit__(self) -> None: //| """Automatically deinitializes the hardware on context exit. See //| :ref:`lifetime-and-contextmanagers` for more info.""" //| ... STATIC mp_obj_t busio_i2c_obj___exit__(size_t n_args, const mp_obj_t *args) { (void)n_args; common_hal_busio_i2c_deinit(MP_OBJ_TO_PTR(args[0])); return mp_const_none; } STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(busio_i2c___exit___obj, 4, 4, busio_i2c_obj___exit__); static void check_lock(busio_i2c_obj_t *self) { asm (""); if (!common_hal_busio_i2c_has_lock(self)) { mp_raise_RuntimeError(MP_ERROR_TEXT("Function requires lock")); } } //| def scan(self) -> List[int]: //| """Scan all I2C addresses between 0x08 and 0x77 inclusive and return a //| list of those that respond. //| //| :return: List of device ids on the I2C bus //| :rtype: list""" //| ... STATIC mp_obj_t busio_i2c_scan(mp_obj_t self_in) { busio_i2c_obj_t *self = MP_OBJ_TO_PTR(self_in); check_for_deinit(self); check_lock(self); mp_obj_t list = mp_obj_new_list(0, NULL); // 7-bit addresses 0b0000xxx and 0b1111xxx are reserved for (int addr = 0x08; addr < 0x78; ++addr) { bool success = common_hal_busio_i2c_probe(self, addr); if (success) { mp_obj_list_append(list, MP_OBJ_NEW_SMALL_INT(addr)); } } return list; } MP_DEFINE_CONST_FUN_OBJ_1(busio_i2c_scan_obj, busio_i2c_scan); //| def try_lock(self) -> bool: //| """Attempts to grab the I2C lock. Returns True on success. //| //| :return: True when lock has been grabbed //| :rtype: bool""" //| ... STATIC mp_obj_t busio_i2c_obj_try_lock(mp_obj_t self_in) { busio_i2c_obj_t *self = MP_OBJ_TO_PTR(self_in); check_for_deinit(self); return mp_obj_new_bool(common_hal_busio_i2c_try_lock(self)); } MP_DEFINE_CONST_FUN_OBJ_1(busio_i2c_try_lock_obj, busio_i2c_obj_try_lock); //| def unlock(self) -> None: //| """Releases the I2C lock.""" //| ... STATIC mp_obj_t busio_i2c_obj_unlock(mp_obj_t self_in) { busio_i2c_obj_t *self = MP_OBJ_TO_PTR(self_in); check_for_deinit(self); common_hal_busio_i2c_unlock(self); return mp_const_none; } MP_DEFINE_CONST_FUN_OBJ_1(busio_i2c_unlock_obj, busio_i2c_obj_unlock); //| import sys //| def readfrom_into( //| self, address: int, buffer: WriteableBuffer, *, start: int = 0, end: int = sys.maxsize //| ) -> None: //| """Read into ``buffer`` from the device selected by ``address``. //| At least one byte must be read. //| //| If ``start`` or ``end`` is provided, then the buffer will be sliced //| as if ``buffer[start:end]`` were passed, but without copying the data. //| The number of bytes read will be the length of ``buffer[start:end]``. //| //| :param int address: 7-bit device address //| :param WriteableBuffer buffer: buffer to write into //| :param int start: beginning of buffer slice //| :param int end: end of buffer slice; if not specified, use ``len(buffer)``""" //| ... STATIC mp_obj_t busio_i2c_readfrom_into(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) { enum { ARG_address, ARG_buffer, ARG_start, ARG_end }; static const mp_arg_t allowed_args[] = { { MP_QSTR_address, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} }, { MP_QSTR_buffer, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} }, { MP_QSTR_start, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} }, { MP_QSTR_end, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = INT_MAX} }, }; busio_i2c_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]); check_for_deinit(self); check_lock(self); mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)]; mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args); mp_buffer_info_t bufinfo; mp_get_buffer_raise(args[ARG_buffer].u_obj, &bufinfo, MP_BUFFER_WRITE); // Compute bounds in terms of elements, not bytes. int stride_in_bytes = mp_binary_get_size('@', bufinfo.typecode, NULL); size_t length = bufinfo.len / stride_in_bytes; int32_t start = args[ARG_start].u_int; const int32_t end = args[ARG_end].u_int; normalize_buffer_bounds(&start, end, &length); mp_arg_validate_length_min(length, 1, MP_QSTR_buffer); // Treat start and length in terms of bytes from now on. start *= stride_in_bytes; length *= stride_in_bytes; uint8_t status = common_hal_busio_i2c_read(self, args[ARG_address].u_int, ((uint8_t *)bufinfo.buf) + start, length); if (status != 0) { mp_raise_OSError(status); } return mp_const_none; } MP_DEFINE_CONST_FUN_OBJ_KW(busio_i2c_readfrom_into_obj, 1, busio_i2c_readfrom_into); //| import sys //| def writeto( //| self, address: int, buffer: ReadableBuffer, *, start: int = 0, end: int = sys.maxsize //| ) -> None: //| """Write the bytes from ``buffer`` to the device selected by ``address`` and //| then transmit a stop bit. //| //| If ``start`` or ``end`` is provided, then the buffer will be sliced //| as if ``buffer[start:end]`` were passed, but without copying the data. //| The number of bytes written will be the length of ``buffer[start:end]``. //| //| Writing a buffer or slice of length zero is permitted, as it can be used //| to poll for the existence of a device. //| //| :param int address: 7-bit device address //| :param ReadableBuffer buffer: buffer containing the bytes to write //| :param int start: beginning of buffer slice //| :param int end: end of buffer slice; if not specified, use ``len(buffer)`` //| """ //| ... STATIC mp_obj_t busio_i2c_writeto(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) { enum { ARG_address, ARG_buffer, ARG_start, ARG_end }; static const mp_arg_t allowed_args[] = { { MP_QSTR_address, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} }, { MP_QSTR_buffer, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} }, { MP_QSTR_start, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} }, { MP_QSTR_end, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = INT_MAX} }, }; busio_i2c_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]); check_for_deinit(self); check_lock(self); mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)]; mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args); // get the buffer to write the data from mp_buffer_info_t bufinfo; mp_get_buffer_raise(args[ARG_buffer].u_obj, &bufinfo, MP_BUFFER_READ); int stride_in_bytes = mp_binary_get_size('@', bufinfo.typecode, NULL); // Compute bounds in terms of elements, not bytes. size_t length = bufinfo.len / stride_in_bytes; int32_t start = args[ARG_start].u_int; const int32_t end = args[ARG_end].u_int; normalize_buffer_bounds(&start, end, &length); // Treat start and length in terms of bytes from now on. start *= stride_in_bytes; length *= stride_in_bytes; // do the transfer uint8_t status = common_hal_busio_i2c_write(self, args[ARG_address].u_int, ((uint8_t *)bufinfo.buf) + start, length); if (status != 0) { mp_raise_OSError(status); } return mp_const_none; } STATIC MP_DEFINE_CONST_FUN_OBJ_KW(busio_i2c_writeto_obj, 1, busio_i2c_writeto); //| import sys //| def writeto_then_readfrom( //| self, //| address: int, //| out_buffer: ReadableBuffer, //| in_buffer: WriteableBuffer, //| *, //| out_start: int = 0, //| out_end: int = sys.maxsize, //| in_start: int = 0, //| in_end: int = sys.maxsize //| ) -> None: //| """Write the bytes from ``out_buffer`` to the device selected by ``address``, generate no stop //| bit, generate a repeated start and read into ``in_buffer``. ``out_buffer`` and //| ``in_buffer`` can be the same buffer because they are used sequentially. //| //| If ``out_start`` or ``out_end`` is provided, then the buffer will be sliced //| as if ``out_buffer[out_start:out_end]`` were passed, but without copying the data. //| The number of bytes written will be the length of ``out_buffer[start:end]``. //| //| If ``in_start`` or ``in_end`` is provided, then the input buffer will be sliced //| as if ``in_buffer[in_start:in_end]`` were passed, //| The number of bytes read will be the length of ``out_buffer[in_start:in_end]``. //| //| :param int address: 7-bit device address //| :param ~circuitpython_typing.ReadableBuffer out_buffer: buffer containing the bytes to write //| :param ~circuitpython_typing.WriteableBuffer in_buffer: buffer to write into //| :param int out_start: beginning of ``out_buffer`` slice //| :param int out_end: end of ``out_buffer`` slice; if not specified, use ``len(out_buffer)`` //| :param int in_start: beginning of ``in_buffer`` slice //| :param int in_end: end of ``in_buffer slice``; if not specified, use ``len(in_buffer)`` //| """ //| ... //| STATIC mp_obj_t busio_i2c_writeto_then_readfrom(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) { enum { ARG_address, ARG_out_buffer, ARG_in_buffer, ARG_out_start, ARG_out_end, ARG_in_start, ARG_in_end }; static const mp_arg_t allowed_args[] = { { MP_QSTR_address, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} }, { MP_QSTR_out_buffer, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} }, { MP_QSTR_in_buffer, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} }, { MP_QSTR_out_start, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} }, { MP_QSTR_out_end, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = INT_MAX} }, { MP_QSTR_in_start, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} }, { MP_QSTR_in_end, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = INT_MAX} }, }; busio_i2c_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]); check_for_deinit(self); check_lock(self); mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)]; mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args); mp_buffer_info_t out_bufinfo; mp_get_buffer_raise(args[ARG_out_buffer].u_obj, &out_bufinfo, MP_BUFFER_READ); int out_stride_in_bytes = mp_binary_get_size('@', out_bufinfo.typecode, NULL); size_t out_length = out_bufinfo.len / out_stride_in_bytes; int32_t out_start = args[ARG_out_start].u_int; const int32_t out_end = args[ARG_out_end].u_int; normalize_buffer_bounds(&out_start, out_end, &out_length); mp_buffer_info_t in_bufinfo; mp_get_buffer_raise(args[ARG_in_buffer].u_obj, &in_bufinfo, MP_BUFFER_WRITE); int in_stride_in_bytes = mp_binary_get_size('@', in_bufinfo.typecode, NULL); size_t in_length = in_bufinfo.len / in_stride_in_bytes; int32_t in_start = args[ARG_in_start].u_int; const int32_t in_end = args[ARG_in_end].u_int; normalize_buffer_bounds(&in_start, in_end, &in_length); mp_arg_validate_length_min(in_length, 1, MP_QSTR_out_buffer); // Treat start and length in terms of bytes from now on. out_start *= out_stride_in_bytes; out_length *= out_stride_in_bytes; in_start *= in_stride_in_bytes; in_length *= in_stride_in_bytes; uint8_t status = common_hal_busio_i2c_write_read(self, args[ARG_address].u_int, ((uint8_t *)out_bufinfo.buf) + out_start, out_length, ((uint8_t *)in_bufinfo.buf) + in_start, in_length); if (status != 0) { mp_raise_OSError(status); } return mp_const_none; } MP_DEFINE_CONST_FUN_OBJ_KW(busio_i2c_writeto_then_readfrom_obj, 1, busio_i2c_writeto_then_readfrom); STATIC const mp_rom_map_elem_t busio_i2c_locals_dict_table[] = { { MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&busio_i2c_deinit_obj) }, { MP_ROM_QSTR(MP_QSTR___enter__), MP_ROM_PTR(&default___enter___obj) }, { MP_ROM_QSTR(MP_QSTR___exit__), MP_ROM_PTR(&busio_i2c___exit___obj) }, { MP_ROM_QSTR(MP_QSTR_scan), MP_ROM_PTR(&busio_i2c_scan_obj) }, { MP_ROM_QSTR(MP_QSTR_try_lock), MP_ROM_PTR(&busio_i2c_try_lock_obj) }, { MP_ROM_QSTR(MP_QSTR_unlock), MP_ROM_PTR(&busio_i2c_unlock_obj) }, { MP_ROM_QSTR(MP_QSTR_readfrom_into), MP_ROM_PTR(&busio_i2c_readfrom_into_obj) }, { MP_ROM_QSTR(MP_QSTR_writeto), MP_ROM_PTR(&busio_i2c_writeto_obj) }, { MP_ROM_QSTR(MP_QSTR_writeto_then_readfrom), MP_ROM_PTR(&busio_i2c_writeto_then_readfrom_obj) }, }; STATIC MP_DEFINE_CONST_DICT(busio_i2c_locals_dict, busio_i2c_locals_dict_table); MP_DEFINE_CONST_OBJ_TYPE( busio_i2c_type, MP_QSTR_I2C, MP_TYPE_FLAG_NONE, make_new, busio_i2c_make_new, locals_dict, &busio_i2c_locals_dict );