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circuitpython/extmod/machine_spi.c

283 lines
12 KiB

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2016 Damien P. George
*
* 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 <stdio.h>
#include <string.h>
#include "py/runtime.h"
#include "extmod/machine_spi.h"
#if MICROPY_PY_MACHINE_SPI
// if a port didn't define MSB/LSB constants then provide them
#ifndef MICROPY_PY_MACHINE_SPI_MSB
#define MICROPY_PY_MACHINE_SPI_MSB (0)
#define MICROPY_PY_MACHINE_SPI_LSB (1)
#endif
/******************************************************************************/
// MicroPython bindings for generic machine.SPI
STATIC mp_obj_t mp_machine_soft_spi_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args);
mp_obj_t mp_machine_spi_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
// check the id argument, if given
if (n_args > 0) {
if (args[0] != MP_OBJ_NEW_SMALL_INT(-1)) {
#if defined(MICROPY_PY_MACHINE_SPI_MAKE_NEW)
// dispatch to port-specific constructor
extern mp_obj_t MICROPY_PY_MACHINE_SPI_MAKE_NEW(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args);
return MICROPY_PY_MACHINE_SPI_MAKE_NEW(type, n_args, n_kw, args);
#else
mp_raise_ValueError("invalid SPI peripheral");
#endif
}
--n_args;
++args;
}
// software SPI
return mp_machine_soft_spi_make_new(type, n_args, n_kw, args);
}
STATIC mp_obj_t machine_spi_init(size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
mp_obj_base_t *s = (mp_obj_base_t*)MP_OBJ_TO_PTR(args[0]);
mp_machine_spi_p_t *spi_p = (mp_machine_spi_p_t*)s->type->protocol;
spi_p->init(s, n_args - 1, args + 1, kw_args);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(machine_spi_init_obj, 1, machine_spi_init);
STATIC mp_obj_t machine_spi_deinit(mp_obj_t self) {
mp_obj_base_t *s = (mp_obj_base_t*)MP_OBJ_TO_PTR(self);
mp_machine_spi_p_t *spi_p = (mp_machine_spi_p_t*)s->type->protocol;
if (spi_p->deinit != NULL) {
spi_p->deinit(s);
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_spi_deinit_obj, machine_spi_deinit);
STATIC void mp_machine_spi_transfer(mp_obj_t self, size_t len, const void *src, void *dest) {
mp_obj_base_t *s = (mp_obj_base_t*)MP_OBJ_TO_PTR(self);
mp_machine_spi_p_t *spi_p = (mp_machine_spi_p_t*)s->type->protocol;
spi_p->transfer(s, len, src, dest);
}
STATIC mp_obj_t mp_machine_spi_read(size_t n_args, const mp_obj_t *args) {
vstr_t vstr;
vstr_init_len(&vstr, mp_obj_get_int(args[1]));
memset(vstr.buf, n_args == 3 ? mp_obj_get_int(args[2]) : 0, vstr.len);
mp_machine_spi_transfer(args[0], vstr.len, vstr.buf, vstr.buf);
return mp_obj_new_str_from_vstr(&mp_type_bytes, &vstr);
}
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_machine_spi_read_obj, 2, 3, mp_machine_spi_read);
STATIC mp_obj_t mp_machine_spi_readinto(size_t n_args, const mp_obj_t *args) {
mp_buffer_info_t bufinfo;
mp_get_buffer_raise(args[1], &bufinfo, MP_BUFFER_WRITE);
memset(bufinfo.buf, n_args == 3 ? mp_obj_get_int(args[2]) : 0, bufinfo.len);
mp_machine_spi_transfer(args[0], bufinfo.len, bufinfo.buf, bufinfo.buf);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_machine_spi_readinto_obj, 2, 3, mp_machine_spi_readinto);
STATIC mp_obj_t mp_machine_spi_write(mp_obj_t self, mp_obj_t wr_buf) {
mp_buffer_info_t src;
mp_get_buffer_raise(wr_buf, &src, MP_BUFFER_READ);
mp_machine_spi_transfer(self, src.len, (const uint8_t*)src.buf, NULL);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_2(mp_machine_spi_write_obj, mp_machine_spi_write);
STATIC mp_obj_t mp_machine_spi_write_readinto(mp_obj_t self, mp_obj_t wr_buf, mp_obj_t rd_buf) {
mp_buffer_info_t src;
mp_get_buffer_raise(wr_buf, &src, MP_BUFFER_READ);
mp_buffer_info_t dest;
mp_get_buffer_raise(rd_buf, &dest, MP_BUFFER_WRITE);
if (src.len != dest.len) {
mp_raise_ValueError("buffers must be the same length");
}
mp_machine_spi_transfer(self, src.len, src.buf, dest.buf);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_3(mp_machine_spi_write_readinto_obj, mp_machine_spi_write_readinto);
STATIC const mp_rom_map_elem_t machine_spi_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&machine_spi_init_obj) },
{ MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&machine_spi_deinit_obj) },
{ MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_machine_spi_read_obj) },
{ MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_machine_spi_readinto_obj) },
{ MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_machine_spi_write_obj) },
{ MP_ROM_QSTR(MP_QSTR_write_readinto), MP_ROM_PTR(&mp_machine_spi_write_readinto_obj) },
{ MP_ROM_QSTR(MP_QSTR_MSB), MP_ROM_INT(MICROPY_PY_MACHINE_SPI_MSB) },
{ MP_ROM_QSTR(MP_QSTR_LSB), MP_ROM_INT(MICROPY_PY_MACHINE_SPI_LSB) },
};
MP_DEFINE_CONST_DICT(mp_machine_spi_locals_dict, machine_spi_locals_dict_table);
/******************************************************************************/
// Implementation of soft SPI
STATIC uint32_t baudrate_from_delay_half(uint32_t delay_half) {
#ifdef MICROPY_HW_SOFTSPI_MIN_DELAY
if (delay_half == MICROPY_HW_SOFTSPI_MIN_DELAY) {
return MICROPY_HW_SOFTSPI_MAX_BAUDRATE;
} else
#endif
{
return 500000 / delay_half;
}
}
STATIC uint32_t baudrate_to_delay_half(uint32_t baudrate) {
#ifdef MICROPY_HW_SOFTSPI_MIN_DELAY
if (baudrate >= MICROPY_HW_SOFTSPI_MAX_BAUDRATE) {
return MICROPY_HW_SOFTSPI_MIN_DELAY;
} else
#endif
{
uint32_t delay_half = 500000 / baudrate;
// round delay_half up so that: actual_baudrate <= requested_baudrate
if (500000 % baudrate != 0) {
delay_half += 1;
}
return delay_half;
}
}
STATIC void mp_machine_soft_spi_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
mp_machine_soft_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);
mp_printf(print, "SoftSPI(baudrate=%u, polarity=%u, phase=%u,"
" sck=" MP_HAL_PIN_FMT ", mosi=" MP_HAL_PIN_FMT ", miso=" MP_HAL_PIN_FMT ")",
baudrate_from_delay_half(self->spi.delay_half), self->spi.polarity, self->spi.phase,
mp_hal_pin_name(self->spi.sck), mp_hal_pin_name(self->spi.mosi), mp_hal_pin_name(self->spi.miso));
}
STATIC mp_obj_t mp_machine_soft_spi_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
enum { ARG_baudrate, ARG_polarity, ARG_phase, ARG_bits, ARG_firstbit, ARG_sck, ARG_mosi, ARG_miso };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_baudrate, MP_ARG_INT, {.u_int = 500000} },
{ 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} },
{ MP_QSTR_firstbit, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = MICROPY_PY_MACHINE_SPI_MSB} },
{ MP_QSTR_sck, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_mosi, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_miso, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
};
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);
// create new object
mp_machine_soft_spi_obj_t *self = m_new_obj(mp_machine_soft_spi_obj_t);
self->base.type = &mp_machine_soft_spi_type;
// set parameters
self->spi.delay_half = baudrate_to_delay_half(args[ARG_baudrate].u_int);
self->spi.polarity = args[ARG_polarity].u_int;
self->spi.phase = args[ARG_phase].u_int;
if (args[ARG_bits].u_int != 8) {
mp_raise_ValueError("bits must be 8");
}
if (args[ARG_firstbit].u_int != MICROPY_PY_MACHINE_SPI_MSB) {
mp_raise_ValueError("firstbit must be MSB");
}
if (args[ARG_sck].u_obj == MP_OBJ_NULL
|| args[ARG_mosi].u_obj == MP_OBJ_NULL
|| args[ARG_miso].u_obj == MP_OBJ_NULL) {
mp_raise_ValueError("must specify all of sck/mosi/miso");
}
self->spi.sck = mp_hal_get_pin_obj(args[ARG_sck].u_obj);
self->spi.mosi = mp_hal_get_pin_obj(args[ARG_mosi].u_obj);
self->spi.miso = mp_hal_get_pin_obj(args[ARG_miso].u_obj);
// configure bus
mp_soft_spi_ioctl(&self->spi, MP_SPI_IOCTL_INIT);
return MP_OBJ_FROM_PTR(self);
}
STATIC void mp_machine_soft_spi_init(mp_obj_base_t *self_in, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
mp_machine_soft_spi_obj_t *self = (mp_machine_soft_spi_obj_t*)self_in;
enum { ARG_baudrate, ARG_polarity, ARG_phase, ARG_sck, ARG_mosi, ARG_miso };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_baudrate, MP_ARG_INT, {.u_int = -1} },
{ MP_QSTR_polarity, MP_ARG_INT, {.u_int = -1} },
{ MP_QSTR_phase, MP_ARG_INT, {.u_int = -1} },
{ MP_QSTR_sck, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_mosi, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_miso, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
};
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);
if (args[ARG_baudrate].u_int != -1) {
self->spi.delay_half = baudrate_to_delay_half(args[ARG_baudrate].u_int);
}
if (args[ARG_polarity].u_int != -1) {
self->spi.polarity = args[ARG_polarity].u_int;
}
if (args[ARG_phase].u_int != -1) {
self->spi.phase = args[ARG_phase].u_int;
}
if (args[ARG_sck].u_obj != MP_OBJ_NULL) {
self->spi.sck = mp_hal_get_pin_obj(args[ARG_sck].u_obj);
}
if (args[ARG_mosi].u_obj != MP_OBJ_NULL) {
self->spi.mosi = mp_hal_get_pin_obj(args[ARG_mosi].u_obj);
}
if (args[ARG_miso].u_obj != MP_OBJ_NULL) {
self->spi.miso = mp_hal_get_pin_obj(args[ARG_miso].u_obj);
}
// configure bus
mp_soft_spi_ioctl(&self->spi, MP_SPI_IOCTL_INIT);
}
STATIC void mp_machine_soft_spi_transfer(mp_obj_base_t *self_in, size_t len, const uint8_t *src, uint8_t *dest) {
mp_machine_soft_spi_obj_t *self = (mp_machine_soft_spi_obj_t*)self_in;
mp_soft_spi_transfer(&self->spi, len, src, dest);
}
const mp_machine_spi_p_t mp_machine_soft_spi_p = {
.init = mp_machine_soft_spi_init,
.deinit = NULL,
.transfer = mp_machine_soft_spi_transfer,
};
const mp_obj_type_t mp_machine_soft_spi_type = {
{ &mp_type_type },
.name = MP_QSTR_SoftSPI,
.print = mp_machine_soft_spi_print,
.make_new = mp_machine_spi_make_new, // delegate to master constructor
.protocol = &mp_machine_soft_spi_p,
.locals_dict = (mp_obj_dict_t*)&mp_machine_spi_locals_dict,
};
#endif // MICROPY_PY_MACHINE_SPI