forked from micropython/micropython
-
Notifications
You must be signed in to change notification settings - Fork 1.2k
/
SPI.c
399 lines (356 loc) · 17.4 KB
/
SPI.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
// This file is part of the CircuitPython project: https://circuitpython.org
//
// SPDX-FileCopyrightText: Copyright (c) 2016 Scott Shawcroft
//
// SPDX-License-Identifier: MIT
// This file contains all of the Python API definitions for the
// bitbangio.SPI class.
#include <string.h>
#include "shared-bindings/bitbangio/SPI.h"
#include "shared-bindings/microcontroller/Pin.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/mperrno.h"
#include "py/runtime.h"
//| class SPI:
//| """A 3-4 wire serial protocol
//|
//| SPI is a serial protocol that has exclusive pins for data in and out of the
//| main device. It is typically faster than :py:class:`~bitbangio.I2C` because a
//| separate pin is used to select a device rather than a transmitted
//| address. This class only manages three of the four SPI lines: `!clock`,
//| `!MOSI`, `!MISO`. Its up to the client to manage the appropriate
//| select line, often abbreviated `!CS` or `!SS`. (This is common because
//| multiple secondaries can share the `!clock`, `!MOSI` and `!MISO` lines
//| and therefore the hardware.)"""
//|
//| def __init__(
//| self,
//| clock: microcontroller.Pin,
//| MOSI: Optional[microcontroller.Pin] = None,
//| MISO: Optional[microcontroller.Pin] = None,
//| ) -> 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 <register-module-reference>` data descriptors.
//|
//|
//| :param ~microcontroller.Pin clock: the pin to use for the clock.
//| :param ~microcontroller.Pin MOSI: the Main Out Selected In pin.
//| :param ~microcontroller.Pin MISO: the Main In Selected Out pin."""
//| ...
// TODO(tannewt): Support LSB SPI.
static mp_obj_t bitbangio_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_clock, ARG_MOSI, ARG_MISO, ARG_baudrate, ARG_polarity, ARG_phase, ARG_bits, ARG_firstbit };
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_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
const mcu_pin_obj_t *clock = validate_obj_is_free_pin(args[ARG_clock].u_obj, MP_QSTR_clock);
const mcu_pin_obj_t *mosi = validate_obj_is_free_pin_or_none(args[ARG_MOSI].u_obj, MP_QSTR_mosi);
const mcu_pin_obj_t *miso = validate_obj_is_free_pin_or_none(args[ARG_MISO].u_obj, MP_QSTR_miso);
bitbangio_spi_obj_t *self = mp_obj_malloc(bitbangio_spi_obj_t, &bitbangio_spi_type);
shared_module_bitbangio_spi_construct(self, clock, mosi, miso);
return (mp_obj_t)self;
}
//| def deinit(self) -> None:
//| """Turn off the SPI bus."""
//| ...
static mp_obj_t bitbangio_spi_obj_deinit(mp_obj_t self_in) {
bitbangio_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);
shared_module_bitbangio_spi_deinit(self);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_1(bitbangio_spi_deinit_obj, bitbangio_spi_obj_deinit);
static void check_for_deinit(bitbangio_spi_obj_t *self) {
if (shared_module_bitbangio_spi_deinited(self)) {
raise_deinited_error();
}
}
//| def __enter__(self) -> SPI:
//| """No-op used by Context Managers."""
//| ...
// Provided by context manager helper.
//| def __exit__(self) -> None:
//| """Automatically deinitializes the hardware when exiting a context. See
//| :ref:`lifetime-and-contextmanagers` for more info."""
//| ...
static mp_obj_t bitbangio_spi_obj___exit__(size_t n_args, const mp_obj_t *args) {
(void)n_args;
shared_module_bitbangio_spi_deinit(args[0]);
return mp_const_none;
}
static MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(bitbangio_spi_obj___exit___obj, 4, 4, bitbangio_spi_obj___exit__);
static void check_lock(bitbangio_spi_obj_t *self) {
if (!shared_module_bitbangio_spi_has_lock(self)) {
mp_raise_RuntimeError(MP_ERROR_TEXT("Function requires lock"));
}
}
//| def configure(
//| self, *, baudrate: int = 100000, polarity: int = 0, phase: int = 0, bits: int = 8
//| ) -> None:
//| """Configures the SPI bus. Only valid when locked.
//|
//| :param int baudrate: the clock rate in Hertz
//| :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"""
//| ...
static mp_obj_t bitbangio_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} },
};
bitbangio_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 = (uint8_t)mp_arg_validate_int_range(args[ARG_polarity].u_int, 0, 1, MP_QSTR_polarity);
uint8_t phase = (uint8_t)mp_arg_validate_int_range(args[ARG_phase].u_int, 0, 1, MP_QSTR_phase);
uint8_t bits = (uint8_t)mp_arg_validate_int_range(args[ARG_bits].u_int, 8, 9, MP_QSTR_bits);
shared_module_bitbangio_spi_configure(self, args[ARG_baudrate].u_int, polarity, phase, bits);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_KW(bitbangio_spi_configure_obj, 1, bitbangio_spi_configure);
//| def try_lock(self) -> bool:
//| """Attempts to grab the SPI lock. Returns True on success.
//|
//| :return: True when lock has been grabbed
//| :rtype: bool"""
//| ...
static mp_obj_t bitbangio_spi_obj_try_lock(mp_obj_t self_in) {
bitbangio_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);
check_for_deinit(self);
return mp_obj_new_bool(shared_module_bitbangio_spi_try_lock(self));
}
MP_DEFINE_CONST_FUN_OBJ_1(bitbangio_spi_try_lock_obj, bitbangio_spi_obj_try_lock);
//| def unlock(self) -> None:
//| """Releases the SPI lock."""
//| ...
static mp_obj_t bitbangio_spi_obj_unlock(mp_obj_t self_in) {
bitbangio_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);
check_for_deinit(self);
shared_module_bitbangio_spi_unlock(self);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_1(bitbangio_spi_unlock_obj, bitbangio_spi_obj_unlock);
//| import sys
//| def write(self, buf: ReadableBuffer, *, start: int = 0, end: int = sys.maxsize) -> None:
//| """Write the data contained in ``buf``. Requires the SPI being locked.
//| If the buffer is empty, nothing happens.
//|
//| 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]``.
//|
//| :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 bitbangio_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} },
};
bitbangio_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);
// Compute bounds in terms of elements, not bytes.
int stride_in_bytes = mp_binary_get_size('@', bufinfo.typecode, NULL);
int32_t start = args[ARG_start].u_int;
size_t length = bufinfo.len / stride_in_bytes;
normalize_buffer_bounds(&start, args[ARG_end].u_int, &length);
// Treat start and length in terms of bytes from now on.
start *= stride_in_bytes;
length *= stride_in_bytes;
if (length == 0) {
return mp_const_none;
}
bool ok = shared_module_bitbangio_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(bitbangio_spi_write_obj, 1, bitbangio_spi_write);
//| import sys
//| def readinto(
//| self,
//| buffer: WriteableBuffer,
//| *,
//| start: int = 0,
//| end: int = sys.maxsize,
//| write_value: int = 0
//| ) -> None:
//| """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.
//|
//| If ``start`` or ``end`` is provided, then the buffer will be sliced
//| as if ``buffer[start:end]`` were passed.
//| The number of bytes read will be the length of ``buffer[start:end]``.
//|
//| :param WriteableBuffer buffer: read bytes into this buffer
//| :param int start: beginning of buffer slice
//| :param int end: end of buffer slice; if not specified, use ``len(buffer)``
//| :param int write_value: value to write while reading
//| """
//| ...
static mp_obj_t bitbangio_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} },
};
bitbangio_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);
int stride_in_bytes = mp_binary_get_size('@', bufinfo.typecode, NULL);
// Compute bounds in terms of elements, not bytes.
int32_t start = args[ARG_start].u_int;
size_t length = bufinfo.len / stride_in_bytes;
normalize_buffer_bounds(&start, args[ARG_end].u_int, &length);
// Treat start and length in terms of bytes from now on.
start *= stride_in_bytes;
length *= stride_in_bytes;
if (length == 0) {
return mp_const_none;
}
bool ok = shared_module_bitbangio_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(bitbangio_spi_readinto_obj, 1, bitbangio_spi_readinto);
//| import sys
//| def write_readinto(
//| self,
//| 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 out the data in ``out_buffer`` while simultaneously reading data into ``in_buffer``.
//| The SPI object must be locked.
//|
//| 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[out_start:out_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]``.
//|
//| The lengths of the slices defined by ``out_buffer[out_start:out_end]``
//| and ``in_buffer[in_start:in_end]`` must be equal.
//| If buffer slice lengths are both 0, nothing happens.
//|
//| :param ReadableBuffer out_buffer: write out bytes from this buffer
//| :param WriteableBuffer in_buffer: read bytes into this buffer
//| :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 bitbangio_spi_write_readinto(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
enum { 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_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} },
};
bitbangio_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_out_buffer].u_obj, &buf_out_info, MP_BUFFER_READ);
int out_stride_in_bytes = mp_binary_get_size('@', buf_out_info.typecode, NULL);
int32_t out_start = args[ARG_out_start].u_int;
size_t out_length = buf_out_info.len / out_stride_in_bytes;
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_in_buffer].u_obj, &buf_in_info, MP_BUFFER_WRITE);
int in_stride_in_bytes = mp_binary_get_size('@', buf_in_info.typecode, NULL);
int32_t in_start = args[ARG_in_start].u_int;
size_t in_length = buf_in_info.len / in_stride_in_bytes;
normalize_buffer_bounds(&in_start, args[ARG_in_end].u_int, &in_length);
// 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;
if (out_length != in_length) {
mp_raise_ValueError(MP_ERROR_TEXT("buffer slices must be of equal length"));
}
if (out_length == 0) {
return mp_const_none;
}
bool ok = shared_module_bitbangio_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(bitbangio_spi_write_readinto_obj, 1, bitbangio_spi_write_readinto);
static const mp_rom_map_elem_t bitbangio_spi_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&bitbangio_spi_deinit_obj) },
{ MP_ROM_QSTR(MP_QSTR___enter__), MP_ROM_PTR(&default___enter___obj) },
{ MP_ROM_QSTR(MP_QSTR___exit__), MP_ROM_PTR(&bitbangio_spi_obj___exit___obj) },
{ MP_ROM_QSTR(MP_QSTR_configure), MP_ROM_PTR(&bitbangio_spi_configure_obj) },
{ MP_ROM_QSTR(MP_QSTR_try_lock), MP_ROM_PTR(&bitbangio_spi_try_lock_obj) },
{ MP_ROM_QSTR(MP_QSTR_unlock), MP_ROM_PTR(&bitbangio_spi_unlock_obj) },
{ MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&bitbangio_spi_readinto_obj) },
{ MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&bitbangio_spi_write_obj) },
{ MP_ROM_QSTR(MP_QSTR_write_readinto), MP_ROM_PTR(&bitbangio_spi_write_readinto_obj) },
};
static MP_DEFINE_CONST_DICT(bitbangio_spi_locals_dict, bitbangio_spi_locals_dict_table);
MP_DEFINE_CONST_OBJ_TYPE(
bitbangio_spi_type,
MP_QSTR_SPI,
MP_TYPE_FLAG_NONE,
make_new, bitbangio_spi_make_new,
locals_dict, &bitbangio_spi_locals_dict
);