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Avoid 8-bit timer overflows in debounce algorithms (#12240)

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* Add fast_timer_t that is 16-bit or 32-bit based on architecture

A 16-bit timer will overflow sooner but be faster to compare on AVR.

* Avoid 8-bit timer overflows in debounce algorithms

Count down remaining elapsed time instead of trying to do 8-bit timer
comparisons.

Add a "none" implementation that is automatically used if DEBOUNCE is
0 otherwise it will break the _pk/_pr count down.

* Avoid unnecessary polling of the entire matrix in sym_eager_pk

The matrix only needs to be updated when a debounce timer expires.

* Avoid unnecessary polling of the entire matrix in sym_eager_pr

The matrix only needs to be updated when a debounce timer expires.

The use of the "needed_update" variable is trying to do what
"matrix_need_update" was added to fix but didn't work because it only
applied when all keys finished debouncing.

* Fix sym_defer_g timing inconsistency compared to other debounce algorithms

DEBOUNCE=5 should process the key after 5ms, not 6ms

* Add debounce tests
This commit is contained in:
Simon Arlott 2021-06-09 08:23:21 +01:00 • committed by GitHub
parent f287597c19
commit b829a1d264
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20 changed files with 1588 additions and 92 deletions
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24
tmk_core/common/timer.h
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@ -1,5 +1,6 @@
/*
Copyright 2011 Jun Wako <wakojun@gmail.com>
Copyright 2021 Simon Arlott
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
@ -17,13 +18,13 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
#pragma once
#if __has_include_next("_timer.h")
# include_next "_timer.h" /* Include the platform's _timer.h */
#endif
#include <stdint.h>
#include <stdbool.h>
#if defined(__AVR__)
# include "avr/timer_avr.h"
#endif
#define TIMER_DIFF(a, b, max) ((max == UINT8_MAX) ? ((uint8_t)((a) - (b))) : ((max == UINT16_MAX) ? ((uint16_t)((a) - (b))) : ((max == UINT32_MAX) ? ((uint32_t)((a) - (b))) : ((a) >= (b) ? (a) - (b) : (max) + 1 - (b) + (a)))))
#define TIMER_DIFF_8(a, b) TIMER_DIFF(a, b, UINT8_MAX)
#define TIMER_DIFF_16(a, b) TIMER_DIFF(a, b, UINT16_MAX)
@ -47,6 +48,21 @@ uint32_t timer_elapsed32(uint32_t last);
#define timer_expired(current, future) ((uint16_t)(current - future) < UINT16_MAX / 2)
#define timer_expired32(current, future) ((uint32_t)(current - future) < UINT32_MAX / 2)
// Use an appropriate timer integer size based on architecture (16-bit will overflow sooner)
#if FAST_TIMER_T_SIZE < 32
# define TIMER_DIFF_FAST(a, b) TIMER_DIFF_16(a, b)
# define timer_expired_fast(current, future) timer_expired(current, future)
typedef uint16_t fast_timer_t;
fast_timer_t inline timer_read_fast(void) { return timer_read(); }
fast_timer_t inline timer_elapsed_fast(fast_timer_t last) { return timer_elapsed(last); }
#else
# define TIMER_DIFF_FAST(a, b) TIMER_DIFF_32(a, b)
# define timer_expired_fast(current, future) timer_expired32(current, future)
typedef uint32_t fast_timer_t;
fast_timer_t inline timer_read_fast(void) { return timer_read32(); }
fast_timer_t inline timer_elapsed_fast(fast_timer_t last) { return timer_elapsed32(last); }
#endif
#ifdef __cplusplus
}
#endif