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
|
/* mbed Microcontroller Library
* Copyright (c) 2006-2013 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "SPI.h"
#if DEVICE_SPI
namespace mbed {
#if DEVICE_SPI_ASYNCH && TRANSACTION_QUEUE_SIZE_SPI
CircularBuffer<Transaction<SPI>, TRANSACTION_QUEUE_SIZE_SPI> SPI::_transaction_buffer;
#endif
SPI::SPI(PinName mosi, PinName miso, PinName sclk, PinName ssel) :
_spi(),
#if DEVICE_SPI_ASYNCH
_irq(this),
_usage(DMA_USAGE_NEVER),
#endif
_bits(8),
_mode(0),
_hz(1000000) {
spi_init(&_spi, mosi, miso, sclk, ssel);
spi_format(&_spi, _bits, _mode, 0);
spi_frequency(&_spi, _hz);
}
void SPI::format(int bits, int mode) {
_bits = bits;
_mode = mode;
SPI::_owner = NULL; // Not that elegant, but works. rmeyer
aquire();
}
void SPI::frequency(int hz) {
_hz = hz;
SPI::_owner = NULL; // Not that elegant, but works. rmeyer
aquire();
}
SPI* SPI::_owner = NULL;
// ignore the fact there are multiple physical spis, and always update if it wasnt us last
void SPI::aquire() {
if (_owner != this) {
spi_format(&_spi, _bits, _mode, 0);
spi_frequency(&_spi, _hz);
_owner = this;
}
}
int SPI::write(int value) {
aquire();
return spi_master_write(&_spi, value);
}
#if DEVICE_SPI_ASYNCH
int SPI::transfer(const void *tx_buffer, int tx_length, void *rx_buffer, int rx_length, unsigned char bit_width, const event_callback_t& callback, int event)
{
if (spi_active(&_spi)) {
return queue_transfer(tx_buffer, tx_length, rx_buffer, rx_length, bit_width, callback, event);
}
start_transfer(tx_buffer, tx_length, rx_buffer, rx_length, bit_width, callback, event);
return 0;
}
void SPI::abort_transfer()
{
spi_abort_asynch(&_spi);
#if TRANSACTION_QUEUE_SIZE_SPI
dequeue_transaction();
#endif
}
void SPI::clear_transfer_buffer()
{
#if TRANSACTION_QUEUE_SIZE_SPI
_transaction_buffer.reset();
#endif
}
void SPI::abort_all_transfers()
{
clear_transfer_buffer();
abort_transfer();
}
int SPI::set_dma_usage(DMAUsage usage)
{
if (spi_active(&_spi)) {
return -1;
}
_usage = usage;
return 0;
}
int SPI::queue_transfer(const void *tx_buffer, int tx_length, void *rx_buffer, int rx_length, unsigned char bit_width, const event_callback_t& callback, int event)
{
#if TRANSACTION_QUEUE_SIZE_SPI
transaction_t t;
t.tx_buffer = const_cast<void *>(tx_buffer);
t.tx_length = tx_length;
t.rx_buffer = rx_buffer;
t.rx_length = rx_length;
t.event = event;
t.callback = callback;
t.width = bit_width;
Transaction<SPI> transaction(this, t);
if (_transaction_buffer.full()) {
return -1; // the buffer is full
} else {
_transaction_buffer.push(transaction);
return 0;
}
#else
return -1;
#endif
}
void SPI::start_transfer(const void *tx_buffer, int tx_length, void *rx_buffer, int rx_length, unsigned char bit_width, const event_callback_t& callback, int event)
{
aquire();
_callback = callback;
_irq.callback(&SPI::irq_handler_asynch);
spi_master_transfer(&_spi, tx_buffer, tx_length, rx_buffer, rx_length, bit_width, _irq.entry(), event , _usage);
}
#if TRANSACTION_QUEUE_SIZE_SPI
void SPI::start_transaction(transaction_t *data)
{
start_transfer(data->tx_buffer, data->tx_length, data->rx_buffer, data->rx_length, data->width, data->callback, data->event);
}
void SPI::dequeue_transaction()
{
Transaction<SPI> t;
if (_transaction_buffer.pop(t)) {
SPI* obj = t.get_object();
transaction_t* data = t.get_transaction();
obj->start_transaction(data);
}
}
#endif
void SPI::irq_handler_asynch(void)
{
int event = spi_irq_handler_asynch(&_spi);
if (_callback && (event & SPI_EVENT_ALL)) {
_callback.call(event & SPI_EVENT_ALL);
}
#if TRANSACTION_QUEUE_SIZE_SPI
if (event & (SPI_EVENT_ALL | SPI_EVENT_INTERNAL_TRANSFER_COMPLETE)) {
// SPI peripheral is free (event happend), dequeue transaction
dequeue_transaction();
}
#endif
}
#endif
} // namespace mbed
#endif
|
