opensteno_qmk/keyboards/rgbkb/mun/matrix.c
2021-09-20 06:18:32 +10:00

76 lines
3 KiB
C

/*
* ----------------------------------------------------------------------------
* "THE BEER-WARE LICENSE" (Revision 42):
* <https://github.com/KarlK90> wrote this file. As long as you retain this
* notice you can do whatever you want with this stuff. If we meet some day, and
* you think this stuff is worth it, you can buy me a beer in return. KarlK90
* ----------------------------------------------------------------------------
*/
#include "matrix.h"
#include "atomic_util.h"
#include "gpio.h"
#define ROWS_PER_HAND (MATRIX_ROWS / 2)
static const pin_t row_pins[MATRIX_ROWS] = MATRIX_ROW_PINS;
static const pin_t col_pins[MATRIX_COLS] = MATRIX_COL_PINS;
void matrix_init_pins(void) {
for (size_t i = 0; i < MATRIX_COLS; i++) {
setPinInputHigh(col_pins[i]);
}
for (size_t i = 0; i < ROWS_PER_HAND; i++) {
setPinOutput(row_pins[i]);
writePinHigh(row_pins[i]);
}
}
void matrix_read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row) {
/* Drive row pin low. */
ATOMIC_BLOCK_FORCEON { writePinLow(row_pins[current_row]); }
matrix_output_select_delay();
/* Read all columns in one go, aka port scanning. */
uint16_t porta = palReadPort(GPIOA);
uint16_t portb = palReadPort(GPIOB);
// clang-format off
/* Order of pins on the mun is: A0, B11, B0, B10, B12, B2, A8
Pin is active low, therefore we have to invert the result. */
matrix_row_t cols = ~(((porta & (0x1 << 0)) >> 0) // A0 (0)
| ((portb & (0x1 << 11)) >> 10) // B11 (1)
| ((portb & (0x1 << 0)) << 2) // B0 (2)
| ((portb & (0x1 << 10)) >> 7) // B10 (3)
| ((portb & (0x1 << 12)) >> 8) // B12 (4)
| ((portb & (0x1 << 2)) << 3) // B2 (5)
| ((porta & (0x1 << 8)) >> 2)); // A8 (6)
// clang-format on
/* Reverse the order of columns for left hand as the board is flipped. */
// if (isLeftHand) {
// #if defined(__arm__)
// /* rbit assembly reverses bit order of 32bit registers. */
// uint32_t temp = cols;
// __asm__("rbit %0, %1" : "=r"(temp) : "r"(temp));
// cols = temp >> 24;
// #else
// /* RISC-V bit manipulation extension not present. Use bit-hack.
// https://graphics.stanford.edu/~seander/bithacks.html#ReverseByteWith32Bits */
// cols = (matrix_row_t)(((cols * 0x0802LU & 0x22110LU) | (cols * 0x8020LU & 0x88440LU)) * 0x10101LU >> 16);
// #endif
// }
current_matrix[current_row] = cols;
/* Drive row pin high again. */
ATOMIC_BLOCK_FORCEON { writePinHigh(row_pins[current_row]); }
matrix_output_unselect_delay(current_row, cols != 0);
}
#if defined(BUSY_WAIT)
void matrix_output_unselect_delay(uint8_t line, bool key_pressed) {
for (int32_t i = 0; i < BUSY_WAIT_INSTRUCTIONS; i++) {
__asm__ volatile("nop" ::: "memory");
}
}
#endif