1 files changed, 49 insertions, 0 deletions

diff --git a/platforms/avr/_wait.h b/platforms/avr/_wait.h
new file mode 100644
index 000000000..683db6ae5
--- /dev/null
+++ b/platforms/avr/_wait.h
@@ -0,0 +1,49 @@
+/* Copyright 2021 QMK
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include <util/delay.h>
+
+#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)
+#define wait_cpuclock(n) __builtin_avr_delay_cycles(n)
+#define CPU_CLOCK F_CPU
+
+/* 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. */
+#ifndef GPIO_INPUT_PIN_DELAY
+#    define GPIO_INPUT_PIN_DELAY 2
+#endif
+
+#define waitInputPinDelay() wait_cpuclock(GPIO_INPUT_PIN_DELAY)