diff --git a/tmk_core/common/avr/_wait.h b/tmk_core/common/avr/_wait.h index 56eb316faf63..ae1a25131ae7 100644 --- a/tmk_core/common/avr/_wait.h +++ b/tmk_core/common/avr/_wait.h @@ -17,8 +17,26 @@ #include -#define wait_ms(ms) _delay_ms(ms) -#define wait_us(us) _delay_us(us) +#define wait_ms(ms) \ + do { \ + if (__builtin_constant_p(ms)) { \ + _delay_ms(ms); \ + } else { \ + for (uint16_t i = ms; i > 0; i--) { \ + _delay_ms(1); \ + } \ + } \ + } while (0) +#define wait_us(us) \ + do { \ + if (__builtin_constant_p(us)) { \ + _delay_us(us); \ + } else { \ + for (uint16_t i = us; i > 0; i--) { \ + _delay_us(1); \ + } \ + } \ + } while (0) /* The AVR series GPIOs have a one clock read delay for changes in the digital input signal. * But here's more margin to make it two clocks. */