summaryrefslogtreecommitdiffstats
path: root/platforms/chibios/drivers/spi_master.c
blob: 28ddcbb2ba67937ca37849a436386641ccc74e0e (plain)
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
/* Copyright 2020 Nick Brassel (tzarc)
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

#include "spi_master.h"

#include "timer.h"

static pin_t currentSlavePin = NO_PIN;

#if defined(K20x) || defined(KL2x)
static SPIConfig spiConfig = {NULL, 0, 0, 0};
#else
static SPIConfig spiConfig = {false, NULL, 0, 0, 0, 0};
#endif

__attribute__((weak)) void spi_init(void) {
    static bool is_initialised = false;
    if (!is_initialised) {
        is_initialised = true;

        // Try releasing special pins for a short time
        setPinInput(SPI_SCK_PIN);
        setPinInput(SPI_MOSI_PIN);
        setPinInput(SPI_MISO_PIN);

        chThdSleepMilliseconds(10);
#if defined(USE_GPIOV1)
        palSetPadMode(PAL_PORT(SPI_SCK_PIN), PAL_PAD(SPI_SCK_PIN), SPI_SCK_PAL_MODE);
        palSetPadMode(PAL_PORT(SPI_MOSI_PIN), PAL_PAD(SPI_MOSI_PIN), SPI_MOSI_PAL_MODE);
        palSetPadMode(PAL_PORT(SPI_MISO_PIN), PAL_PAD(SPI_MISO_PIN), SPI_MISO_PAL_MODE);
#else
        palSetPadMode(PAL_PORT(SPI_SCK_PIN), PAL_PAD(SPI_SCK_PIN), PAL_MODE_ALTERNATE(SPI_SCK_PAL_MODE) | PAL_STM32_OTYPE_PUSHPULL | PAL_STM32_OSPEED_HIGHEST);
        palSetPadMode(PAL_PORT(SPI_MOSI_PIN), PAL_PAD(SPI_MOSI_PIN), PAL_MODE_ALTERNATE(SPI_MOSI_PAL_MODE) | PAL_STM32_OTYPE_PUSHPULL | PAL_STM32_OSPEED_HIGHEST);
        palSetPadMode(PAL_PORT(SPI_MISO_PIN), PAL_PAD(SPI_MISO_PIN), PAL_MODE_ALTERNATE(SPI_MISO_PAL_MODE) | PAL_STM32_OTYPE_PUSHPULL | PAL_STM32_OSPEED_HIGHEST);
#endif
    }
}

bool spi_start(pin_t slavePin, bool lsbFirst, uint8_t mode, uint16_t divisor) {
    if (currentSlavePin != NO_PIN || slavePin == NO_PIN) {
        return false;
    }

    uint16_t roundedDivisor = 2;
    while (roundedDivisor < divisor) {
        roundedDivisor <<= 1;
    }

    if (roundedDivisor < 2 || roundedDivisor > 256) {
        return false;
    }

#if defined(K20x) || defined(KL2x)
    spiConfig.tar0 = SPIx_CTARn_FMSZ(7) | SPIx_CTARn_ASC(1);

    if (lsbFirst) {
        spiConfig.tar0 |= SPIx_CTARn_LSBFE;
    }

    switch (mode) {
        case 0:
            break;
        case 1:
            spiConfig.tar0 |= SPIx_CTARn_CPHA;
            break;
        case 2:
            spiConfig.tar0 |= SPIx_CTARn_CPOL;
            break;
        case 3:
            spiConfig.tar0 |= SPIx_CTARn_CPHA | SPIx_CTARn_CPOL;
            break;
    }

    switch (roundedDivisor) {
        case 2:
            spiConfig.tar0 |= SPIx_CTARn_BR(0);
            break;
        case 4:
            spiConfig.tar0 |= SPIx_CTARn_BR(1);
            break;
        case 8:
            spiConfig.tar0 |= SPIx_CTARn_BR(3);
            break;
        case 16:
            spiConfig.tar0 |= SPIx_CTARn_BR(4);
            break;
        case 32:
            spiConfig.tar0 |= SPIx_CTARn_BR(5);
            break;
        case 64:
            spiConfig.tar0 |= SPIx_CTARn_BR(6);
            break;
        case 128:
            spiConfig.tar0 |= SPIx_CTARn_BR(7);
            break;
        case 256:
            spiConfig.tar0 |= SPIx_CTARn_BR(8);
            break;
    }
#else
    spiConfig.cr1 = 0;

    if (lsbFirst) {
        spiConfig.cr1 |= SPI_CR1_LSBFIRST;
    }

    switch (mode) {
        case 0:
            break;
        case 1:
            spiConfig.cr1 |= SPI_CR1_CPHA;
            break;
        case 2:
            spiConfig.cr1 |= SPI_CR1_CPOL;
            break;
        case 3:
            spiConfig.cr1 |= SPI_CR1_CPHA | SPI_CR1_CPOL;
            break;
    }

    switch (roundedDivisor) {
        case 2:
            break;
        case 4:
            spiConfig.cr1 |= SPI_CR1_BR_0;
            break;
        case 8:
            spiConfig.cr1 |= SPI_CR1_BR_1;
            break;
        case 16:
            spiConfig.cr1 |= SPI_CR1_BR_1 | SPI_CR1_BR_0;
            break;
        case 32:
            spiConfig.cr1 |= SPI_CR1_BR_2;
            break;
        case 64:
            spiConfig.cr1 |= SPI_CR1_BR_2 | SPI_CR1_BR_0;
            break;
        case 128:
            spiConfig.cr1 |= SPI_CR1_BR_2 | SPI_CR1_BR_1;
            break;
        case 256:
            spiConfig.cr1 |= SPI_CR1_BR_2 | SPI_CR1_BR_1 | SPI_CR1_BR_0;
            break;
    }
#endif

    currentSlavePin  = slavePin;
    spiConfig.ssport = PAL_PORT(slavePin);
    spiConfig.sspad  = PAL_PAD(slavePin);

    setPinOutput(slavePin);
    spiStart(&SPI_DRIVER, &spiConfig);
    spiSelect(&SPI_DRIVER);

    return true;
}

spi_status_t spi_write(uint8_t data) {
    uint8_t rxData;
    spiExchange(&SPI_DRIVER, 1, &data, &rxData);

    return rxData;
}

spi_status_t spi_read(void) {
    uint8_t data = 0;
    spiReceive(&SPI_DRIVER, 1, &data);

    return data;
}

spi_status_t spi_transmit(const uint8_t *data, uint16_t length) {
    spiSend(&SPI_DRIVER, length, data);
    return SPI_STATUS_SUCCESS;
}

spi_status_t spi_receive(uint8_t *data, uint16_t length) {
    spiReceive(&SPI_DRIVER, length, data);
    return SPI_STATUS_SUCCESS;
}

void spi_stop(void) {
    if (currentSlavePin != NO_PIN) {
        spiUnselect(&SPI_DRIVER);
        spiStop(&SPI_DRIVER);
        currentSlavePin = NO_PIN;
    }
}