summaryrefslogtreecommitdiff
path: root/keyboards/hazel/bad_wings/matrix.c
blob: 496bebd58f9cf9f75c9f659119005e70db91cb29 (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
// Copyright 2022 @sadekbaroudi (Sadek Baroudi)
// Copyright 2023 @jasonhazel (Jason Hazel)
// SPDX-License-Identifier: GPL-3.0-or-later

#include "quantum.h"
#include "spi_master.h"
#include <string.h> /* memset */
#include <unistd.h> /* close */
#include "quantum.h"
#include "matrix.h"

#if (!defined(SHIFTREG_MATRIX_COL_CS))
#    error Missing shift register I/O pin definitions
#endif

int matrixArraySize = SHIFTREG_ROWS * sizeof(matrix_row_t);
matrix_row_t oldMatrix[SHIFTREG_ROWS];

#define SHIFTREG_OUTPUT_BITS 8
pin_t rowPinsSR[SHIFTREG_ROWS] = MATRIX_ROW_PINS_SR;

// semaphore to make sure SPI doesn't get called multiple times
static bool shiftRegisterSPILocked = false;

void semaphore_lock(bool value) {
    shiftRegisterSPILocked = value;
}

bool semaphore_is_locked(void) {
    return shiftRegisterSPILocked;
}

void sr_74hc595_spi_stop(void) {
    spi_stop();
    semaphore_lock(false);
}

bool sr_74hc595_spi_start(void) {
    if (!spi_start(SHIFTREG_MATRIX_COL_CS, false, 0, SHIFTREG_DIVISOR)) {
        dprintf("74hc595 matrix: failed to start spi\n");
        sr_74hc595_spi_stop();
        return false;
    }

    semaphore_lock(true);
    wait_us(1); // not sure if I need this
    return true;
}

bool sr_74hc595_spi_send_byte(uint8_t data) {
    sr_74hc595_spi_start();
    writePinLow(SHIFTREG_MATRIX_COL_CS);
    matrix_io_delay();
    spi_write(data);
    matrix_io_delay();
    writePinHigh(SHIFTREG_MATRIX_COL_CS);
    sr_74hc595_spi_stop();
    return true;
}

/**
 * Set the entire shift register to be full of inactive bits
 */
void clearColumns(void) {
    uint8_t value = 0b00000000;
    sr_74hc595_spi_send_byte(value);
}

void setColumn(int columnShift, bool test_run) {
    uint8_t columnShiftByte = ((uint8_t)1 << columnShift);
    if(test_run) {
        dprintf("byte sent: %d\n", columnShiftByte);
    }
    sr_74hc595_spi_send_byte(columnShiftByte);
}

/*
 * override of the qmk intialization function
 */
void matrix_init_custom(void) {
    wait_ms(300);
    spi_init();
    // Set up the initial states for all the row pins
    for (int r = 0; r < SHIFTREG_ROWS; r++) {
        // Note: This needs to use the internal pull down resistors, and atmegas do *not* support that
        setPinInputLow(rowPinsSR[r]);
    }

    // Set the CS to low by default, and specify as an output pin
    writePinHigh(SHIFTREG_MATRIX_COL_CS); // should be high when using SPI?
    setPinOutput(SHIFTREG_MATRIX_COL_CS);

    // Since it's the init, deactivate all the columns. We'll activate once we get to the matrix scan
    clearColumns();
}

bool matrix_scan_custom(matrix_row_t current_matrix[]) {
    // respect the semaphore
    if (semaphore_is_locked()) {
        return false;
    }

    // Keep track of if something was modified
    bool matrix_has_changed = false;

    // reset the current matrix, as we'll be updating and comparing to the old matrix
    memset(current_matrix, 0, matrixArraySize);


    bool debug_output = false;
    // Loop through the columns, activating one at a time, and read the rows, and place in the new current_matrix
    for (int c = 0; c < SHIFTREG_COLS; c++) {
        if (debug_output) {
            dprintf("column iteration: %d\n", c);
        }
        setColumn(c, debug_output);
        matrix_io_delay();

        for (int r = 0; r < SHIFTREG_ROWS; r++) {
            current_matrix[r] |= ((readPin(rowPinsSR[r]) ? 1 : 0) << c);
        }
    }

    matrix_has_changed = memcmp(current_matrix, oldMatrix, matrixArraySize) != 0;
    memcpy(oldMatrix, current_matrix, matrixArraySize);

    if (matrix_has_changed) {
        matrix_print();
    }


    // Deactivate all the columns for the next run.
    clearColumns();
    matrix_io_delay();

    return matrix_has_changed;
}