altos/drivers: Make quadrature debounce longer by default. Fix state tracking

This increases the default debounce time for quadrature encoders to
30ms, which cleans up the mechanical encoders on TeleLCO v0.2. Also
change state tracking to explicitly check for expected state values to
avoid mis-triggering.

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 14 insertions, 10 deletions

diff --git a/src/drivers/ao_quadrature.c b/src/drivers/ao_quadrature.c
index deecfb79..d9cdfe7c 100644
--- a/src/drivers/ao_quadrature.c
+++ b/src/drivers/ao_quadrature.c
@@ -39,20 +39,24 @@ static struct ao_debounce ao_debounce_state[AO_QUADRATURE_COUNT][2];
 #define pinb(q) AO_QUADRATURE_ ## q ## _B ## _PIN
 #define isr(q)  ao_quadrature_isr_ ## q
 
-#define DEBOUNCE	10
+#ifndef AO_QUADRATURE_DEBOUNCE
+#define AO_QUADRATURE_DEBOUNCE	30
+#endif
 
 static uint8_t
 ao_debounce(uint8_t cur, struct ao_debounce *debounce)
 {
-	if (cur == debounce->state)
-		debounce->count = 0;
-	else {
-		if (++debounce->count == DEBOUNCE) {
-			debounce->state = cur;
-			debounce->count = 0;
-		}
+#if AO_QUADRATURE_DEBOUNCE > 0
+	if (debounce->count > 0) {
+		debounce->count--;
+	} else if (cur != debounce->state) {
+		debounce->state = cur;
+		debounce->count = AO_QUADRATURE_DEBOUNCE;
 	}
 	return debounce->state;
+#else
+	return cur;
+#endif
 }
 
 static uint16_t
@@ -84,9 +88,9 @@ _ao_quadrature_set(uint8_t q, uint8_t new) {
 	uint8_t	old = ao_quadrature_state[q];
 
 	if (old != new && new == 0) {
-		if (old & 2)
+		if (old == 2)
 			_ao_quadrature_queue(q, 1);
-		else if (old & 1)
+		else if (old == 1)
 			_ao_quadrature_queue(q, -1);
 	}
 	ao_quadrature_state[q] = new;