/* * 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.SPI class. #include #include "shared-bindings/microcontroller/Pin.h" #include "shared-bindings/busio/SPI.h" #include "shared-bindings/util.h" #include "lib/utils/buffer_helper.h" #include "lib/utils/context_manager_helpers.h" #include "py/mperrno.h" #include "py/objproperty.h" #include "py/runtime.h" #include "supervisor/shared/translate.h" //| .. currentmodule:: busio //| //| :class:`SPI` -- a 3-4 wire serial protocol //| ----------------------------------------------- //| //| SPI is a serial protocol that has exclusive pins for data in and out of the //| master. It is typically faster than :py:class:`~busio.I2C` because a //| separate pin is used to control the active slave rather than a transitted //| address. This class only manages three of the four SPI lines: `!clock`, //| `!MOSI`, `!MISO`. Its up to the client to manage the appropriate slave //| select line. (This is common because multiple slaves can share the `!clock`, //| `!MOSI` and `!MISO` lines and therefore the hardware.) //| //| .. class:: SPI(clock, MOSI=None, MISO=None) //| //| Construct an SPI object on the given pins. //| //| .. seealso:: Using this class directly requires careful lock management. //| Instead, use :class:`~adafruit_bus_device.spi_device.SPIDevice` 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 clock: the pin to use for the clock. //| :param ~microcontroller.Pin MOSI: the Master Out Slave In pin. //| :param ~microcontroller.Pin MISO: the Master In Slave Out pin. //| // TODO(tannewt): Support LSB SPI. STATIC mp_obj_t busio_spi_make_new(const mp_obj_type_t *type, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) { busio_spi_obj_t *self = m_new_obj(busio_spi_obj_t); self->base.type = &busio_spi_type; enum { ARG_clock, ARG_MOSI, ARG_MISO }; static const mp_arg_t allowed_args[] = { { MP_QSTR_clock, MP_ARG_REQUIRED | MP_ARG_OBJ }, { MP_QSTR_MOSI, MP_ARG_OBJ, {.u_obj = mp_const_none} }, { MP_QSTR_MISO, MP_ARG_OBJ, {.u_obj = mp_const_none} }, }; mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)]; mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args); assert_pin(args[ARG_clock].u_obj, false); assert_pin(args[ARG_MOSI].u_obj, true); assert_pin(args[ARG_MISO].u_obj, true); const mcu_pin_obj_t* clock = MP_OBJ_TO_PTR(args[ARG_clock].u_obj); assert_pin_free(clock); const mcu_pin_obj_t* mosi = MP_OBJ_TO_PTR(args[ARG_MOSI].u_obj); assert_pin_free(mosi); const mcu_pin_obj_t* miso = MP_OBJ_TO_PTR(args[ARG_MISO].u_obj); assert_pin_free(miso); common_hal_busio_spi_construct(self, clock, mosi, miso); return (mp_obj_t)self; } //| .. method:: deinit() //| //| Turn off the SPI bus. //| STATIC mp_obj_t busio_spi_obj_deinit(mp_obj_t self_in) { busio_spi_obj_t *self = MP_OBJ_TO_PTR(self_in); common_hal_busio_spi_deinit(self); return mp_const_none; } MP_DEFINE_CONST_FUN_OBJ_1(busio_spi_deinit_obj, busio_spi_obj_deinit); //| .. method:: __enter__() //| //| No-op used by Context Managers. //| // Provided by context manager helper. //| .. method:: __exit__() //| //| Automatically deinitializes the hardware when exiting a context. See //| :ref:`lifetime-and-contextmanagers` for more info. //| STATIC mp_obj_t busio_spi_obj___exit__(size_t n_args, const mp_obj_t *args) { (void)n_args; common_hal_busio_spi_deinit(args[0]); return mp_const_none; } STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(busio_spi_obj___exit___obj, 4, 4, busio_spi_obj___exit__); STATIC void check_lock(busio_spi_obj_t *self) { asm(""); if (!common_hal_busio_spi_has_lock(self)) { mp_raise_RuntimeError(translate("Function requires lock")); } } STATIC void check_for_deinit(busio_spi_obj_t *self) { if (common_hal_busio_spi_deinited(self)) { raise_deinited_error(); } } //| .. method:: configure(*, baudrate=100000, polarity=0, phase=0, bits=8) //| //| Configures the SPI bus. The SPI object must be locked. //| //| :param int baudrate: the desired clock rate in Hertz. The actual clock rate may be higher or lower //| due to the granularity of available clock settings. //| Check the `frequency` attribute for the actual clock rate. //| :param int polarity: the base state of the clock line (0 or 1) //| :param int phase: the edge of the clock that data is captured. First (0) //| or second (1). Rising or falling depends on clock polarity. //| :param int bits: the number of bits per word //| //| .. note:: On the SAMD21, it is possible to set the baudrate to 24 MHz, but that //| speed is not guaranteed to work. 12 MHz is the next available lower speed, and is //| within spec for the SAMD21. //| //| .. note:: On the nRF52840, these baudrates are available: 125kHz, 250kHz, 1MHz, 2MHz, 4MHz, //| and 8MHz. 16MHz and 32MHz are also available, but only on the first //| `busio.SPI` object you create. Two more ``busio.SPI`` objects can be created, but they are restricted //| to 8MHz maximum. This is a hardware restriction: there is only one high-speed SPI peripheral. //| If you pick a a baudrate other than one of these, the nearest lower //| baudrate will be chosen, with a minimum of 125kHz. STATIC mp_obj_t busio_spi_configure(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) { enum { ARG_baudrate, ARG_polarity, ARG_phase, ARG_bits }; static const mp_arg_t allowed_args[] = { { MP_QSTR_baudrate, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 100000} }, { MP_QSTR_polarity, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} }, { MP_QSTR_phase, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} }, { MP_QSTR_bits, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 8} }, }; busio_spi_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); uint8_t polarity = args[ARG_polarity].u_int; if (polarity != 0 && polarity != 1) { mp_raise_ValueError(translate("Invalid polarity")); } uint8_t phase = args[ARG_phase].u_int; if (phase != 0 && phase != 1) { mp_raise_ValueError(translate("Invalid phase")); } uint8_t bits = args[ARG_bits].u_int; if (bits != 8 && bits != 9) { mp_raise_ValueError(translate("Invalid number of bits")); } if (!common_hal_busio_spi_configure(self, args[ARG_baudrate].u_int, polarity, phase, bits)) { mp_raise_OSError(MP_EIO); } return mp_const_none; } MP_DEFINE_CONST_FUN_OBJ_KW(busio_spi_configure_obj, 1, busio_spi_configure); //| .. method:: try_lock() //| //| Attempts to grab the SPI lock. Returns True on success. //| //| :return: True when lock has been grabbed //| :rtype: bool //| STATIC mp_obj_t busio_spi_obj_try_lock(mp_obj_t self_in) { busio_spi_obj_t *self = MP_OBJ_TO_PTR(self_in); return mp_obj_new_bool(common_hal_busio_spi_try_lock(self)); } MP_DEFINE_CONST_FUN_OBJ_1(busio_spi_try_lock_obj, busio_spi_obj_try_lock); //| .. method:: unlock() //| //| Releases the SPI lock. //| STATIC mp_obj_t busio_spi_obj_unlock(mp_obj_t self_in) { busio_spi_obj_t *self = MP_OBJ_TO_PTR(self_in); check_for_deinit(self); common_hal_busio_spi_unlock(self); return mp_const_none; } MP_DEFINE_CONST_FUN_OBJ_1(busio_spi_unlock_obj, busio_spi_obj_unlock); //| .. method:: write(buffer, *, start=0, end=None) //| //| Write the data contained in ``buffer``. The SPI object must be locked. //| If the buffer is empty, nothing happens. //| //| :param bytearray buffer: Write out the data in this buffer //| :param int start: Start of the slice of ``buffer`` to write out: ``buffer[start:end]`` //| :param int end: End of the slice; this index is not included. Defaults to ``len(buffer)`` //| STATIC mp_obj_t busio_spi_write(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) { enum { ARG_buffer, ARG_start, ARG_end }; static const mp_arg_t allowed_args[] = { { 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_spi_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_READ); int32_t start = args[ARG_start].u_int; uint32_t length = bufinfo.len; normalize_buffer_bounds(&start, args[ARG_end].u_int, &length); if (length == 0) { return mp_const_none; } bool ok = common_hal_busio_spi_write(self, ((uint8_t*)bufinfo.buf) + start, length); if (!ok) { mp_raise_OSError(MP_EIO); } return mp_const_none; } MP_DEFINE_CONST_FUN_OBJ_KW(busio_spi_write_obj, 2, busio_spi_write); //| .. method:: readinto(buffer, *, start=0, end=None, write_value=0) //| //| Read into ``buffer`` while writing ``write_value`` for each byte read. //| The SPI object must be locked. //| If the number of bytes to read is 0, nothing happens. //| //| :param bytearray buffer: Read data into this buffer //| :param int start: Start of the slice of ``buffer`` to read into: ``buffer[start:end]`` //| :param int end: End of the slice; this index is not included. Defaults to ``len(buffer)`` //| :param int write_value: Value to write while reading. (Usually ignored.) //| STATIC mp_obj_t busio_spi_readinto(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) { enum { ARG_buffer, ARG_start, ARG_end, ARG_write_value }; static const mp_arg_t allowed_args[] = { { 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} }, { MP_QSTR_write_value,MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} }, }; busio_spi_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); int32_t start = args[ARG_start].u_int; uint32_t length = bufinfo.len; normalize_buffer_bounds(&start, args[ARG_end].u_int, &length); if (length == 0) { return mp_const_none; } bool ok = common_hal_busio_spi_read(self, ((uint8_t*)bufinfo.buf) + start, length, args[ARG_write_value].u_int); if (!ok) { mp_raise_OSError(MP_EIO); } return mp_const_none; } MP_DEFINE_CONST_FUN_OBJ_KW(busio_spi_readinto_obj, 2, busio_spi_readinto); //| .. method:: write_readinto(buffer_out, buffer_in, *, out_start=0, out_end=None, in_start=0, in_end=None) //| //| Write out the data in ``buffer_out`` while simultaneously reading data into ``buffer_in``. //| The SPI object must be locked. //| The lengths of the slices defined by ``buffer_out[out_start:out_end]`` and ``buffer_in[in_start:in_end]`` //| must be equal. //| If buffer slice lengths are both 0, nothing happens. //| //| :param bytearray buffer_out: Write out the data in this buffer //| :param bytearray buffer_in: Read data into this buffer //| :param int out_start: Start of the slice of buffer_out to write out: ``buffer_out[out_start:out_end]`` //| :param int out_end: End of the slice; this index is not included. Defaults to ``len(buffer_out)`` //| :param int in_start: Start of the slice of ``buffer_in`` to read into: ``buffer_in[in_start:in_end]`` //| :param int in_end: End of the slice; this index is not included. Defaults to ``len(buffer_in)`` //| STATIC mp_obj_t busio_spi_write_readinto(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) { enum { ARG_buffer_out, ARG_buffer_in, ARG_out_start, ARG_out_end, ARG_in_start, ARG_in_end }; static const mp_arg_t allowed_args[] = { { MP_QSTR_buffer_out, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} }, { MP_QSTR_buffer_in, 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_spi_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 buf_out_info; mp_get_buffer_raise(args[ARG_buffer_out].u_obj, &buf_out_info, MP_BUFFER_READ); int32_t out_start = args[ARG_out_start].u_int; uint32_t out_length = buf_out_info.len; normalize_buffer_bounds(&out_start, args[ARG_out_end].u_int, &out_length); mp_buffer_info_t buf_in_info; mp_get_buffer_raise(args[ARG_buffer_in].u_obj, &buf_in_info, MP_BUFFER_WRITE); int32_t in_start = args[ARG_in_start].u_int; uint32_t in_length = buf_in_info.len; normalize_buffer_bounds(&in_start, args[ARG_in_end].u_int, &in_length); if (out_length != in_length) { mp_raise_ValueError(translate("buffer slices must be of equal length")); } if (out_length == 0) { return mp_const_none; } bool ok = common_hal_busio_spi_transfer(self, ((uint8_t*)buf_out_info.buf) + out_start, ((uint8_t*)buf_in_info.buf) + in_start, out_length); if (!ok) { mp_raise_OSError(MP_EIO); } return mp_const_none; } MP_DEFINE_CONST_FUN_OBJ_KW(busio_spi_write_readinto_obj, 2, busio_spi_write_readinto); //| .. attribute:: frequency //| //| The actual SPI bus frequency. This may not match the frequency requested //| due to internal limitations. //| STATIC mp_obj_t busio_spi_obj_get_frequency(mp_obj_t self_in) { busio_spi_obj_t *self = MP_OBJ_TO_PTR(self_in); check_for_deinit(self); return MP_OBJ_NEW_SMALL_INT(common_hal_busio_spi_get_frequency(self)); } MP_DEFINE_CONST_FUN_OBJ_1(busio_spi_get_frequency_obj, busio_spi_obj_get_frequency); const mp_obj_property_t busio_spi_frequency_obj = { .base.type = &mp_type_property, .proxy = {(mp_obj_t)&busio_spi_get_frequency_obj, (mp_obj_t)&mp_const_none_obj, (mp_obj_t)&mp_const_none_obj}, }; STATIC const mp_rom_map_elem_t busio_spi_locals_dict_table[] = { { MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&busio_spi_deinit_obj) }, { MP_ROM_QSTR(MP_QSTR___enter__), MP_ROM_PTR(&default___enter___obj) }, { MP_ROM_QSTR(MP_QSTR___exit__), MP_ROM_PTR(&busio_spi_obj___exit___obj) }, { MP_ROM_QSTR(MP_QSTR_configure), MP_ROM_PTR(&busio_spi_configure_obj) }, { MP_ROM_QSTR(MP_QSTR_try_lock), MP_ROM_PTR(&busio_spi_try_lock_obj) }, { MP_ROM_QSTR(MP_QSTR_unlock), MP_ROM_PTR(&busio_spi_unlock_obj) }, { MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&busio_spi_readinto_obj) }, { MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&busio_spi_write_obj) }, { MP_ROM_QSTR(MP_QSTR_write_readinto), MP_ROM_PTR(&busio_spi_write_readinto_obj) }, { MP_ROM_QSTR(MP_QSTR_frequency), MP_ROM_PTR(&busio_spi_frequency_obj) } }; STATIC MP_DEFINE_CONST_DICT(busio_spi_locals_dict, busio_spi_locals_dict_table); const mp_obj_type_t busio_spi_type = { { &mp_type_type }, .name = MP_QSTR_SPI, .make_new = busio_spi_make_new, .locals_dict = (mp_obj_dict_t*)&busio_spi_locals_dict, };