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authorLars-Dominik Braun <lars@6xq.net>2015-02-10 13:13:26 +0100
committerLars-Dominik Braun <lars@6xq.net>2015-02-10 13:13:26 +0100
commitdd81f8691752b3e4cdfb2b0fc43eb336aa9d4290 (patch)
treef37650f5f1d0c35f8f1036f52c647d3a424036cb
parentf76febc83d304119f90b2faf7c1f275292c968f7 (diff)
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accel: Nonblocking
-rw-r--r--accel.c107
-rw-r--r--accel.h2
-rw-r--r--gyro.c8
3 files changed, 67 insertions, 50 deletions
diff --git a/accel.c b/accel.c
index 77126d4..6dcb5c9 100644
--- a/accel.c
+++ b/accel.c
@@ -52,8 +52,15 @@ static uint8_t horizonStable = 0;
/* previous measurement */
static horizon horizonPrevSign = HORIZON_NONE;
-/* currently reading from i2c */
-static bool reading = false;
+/* driver state */
+#define STOPPED 0
+#define START_REQUEST 1
+#define STARTING 2
+#define STOP_REQUEST 3
+#define STOPPING 4
+#define READING 5
+#define IDLE 6
+static uint8_t state = STOPPED;
/* data ready interrupt
*/
@@ -76,22 +83,10 @@ void accelInit () {
PCMSK1 = (1 << PCINT9) | (1 << PCINT8);
}
-/* XXX: make nonblocking */
void accelStart () {
- /* configuration:
- * disable power-down-mode, enable z-axis
- * defaults
- * push-pull, high-active, data ready interrupt on int2
- */
- uint8_t data[] = {0b01000100, 0b0, 0b00100000};
-
- if (!twRequest (TWM_WRITE, LIS302DL, LIS302DL_CTRLREG1, data,
- sizeof (data)/sizeof (*data))) {
- assert (0);
- }
- sleepwhile (twr.status == TWST_WAIT);
- assert (twr.status == TWST_OK);
- disableWakeup (WAKE_I2C);
+ assert (state == STOPPED);
+ state = START_REQUEST;
+
}
/* register shake gesture
@@ -159,38 +154,62 @@ static void accelProcessHorizon () {
horizonPrevSign = zval >= 0 ? HORIZON_POS : HORIZON_NEG;
}
-bool accelProcess () {
- if (reading && shouldWakeup (WAKE_I2C)) {
- disableWakeup (WAKE_I2C);
- reading = false;
- /* the bus might be in use again already */
- //assert (twr.status == TWST_OK);
- accelProcessHorizon ();
-
- /* calculate normalized z (i.e. without earth gravity component) */
- if (horizonSign == HORIZON_NEG) {
- zvalnormal = zval - (-ACCEL_1G);
- } else if (horizonSign == HORIZON_POS) {
- zvalnormal = zval - ACCEL_1G;
+void accelProcess () {
+ switch (state) {
+ case START_REQUEST: {
+ /* configuration:
+ * disable power-down-mode, enable z-axis
+ * defaults
+ * push-pull, high-active, data ready interrupt on int2
+ */
+ static uint8_t data[] = {0b01000100, 0b0, 0b00100000};
+
+ const bool ret = twRequest (TWM_WRITE, LIS302DL, LIS302DL_CTRLREG1, data,
+ sizeof (data)/sizeof (*data));
+ if (ret) {
+ state = STARTING;
+ }
+ break;
}
- accelProcessShake ();
- /* new data transfered */
- return true;
- } else {
- if (shouldWakeup (WAKE_ACCEL) && twr.status == TWST_OK) {
+ case STARTING:
+ if (shouldWakeup (WAKE_I2C)) {
+ disableWakeup (WAKE_I2C);
+ state = IDLE;
+ }
+ break;
+
+ case IDLE:
/* new data available in device buffer and bus is free */
- if (!twRequest (TWM_READ, LIS302DL, LIS302DL_OUTZ,
- (uint8_t *) &zval, sizeof (zval))) {
- assert (0);
- } else {
- /* wakeup source is disabled by isr to prevent race condition */
- reading = true;
+ if (shouldWakeup (WAKE_ACCEL) && twRequest (TWM_READ, LIS302DL,
+ LIS302DL_OUTZ, (uint8_t *) &zval, sizeof (zval))) {
+ state = READING;
}
- }
- }
+ break;
+
+ case READING:
+ if (shouldWakeup (WAKE_I2C)) {
+ disableWakeup (WAKE_I2C);
+ state = IDLE;
+ /* the bus might be in use again already */
+ //assert (twr.status == TWST_OK);
+ accelProcessHorizon ();
+
+ /* calculate normalized z (i.e. without earth gravity component) */
+ if (horizonSign == HORIZON_NEG) {
+ zvalnormal = zval - (-ACCEL_1G);
+ } else if (horizonSign == HORIZON_POS) {
+ zvalnormal = zval - ACCEL_1G;
+ }
+
+ accelProcessShake ();
+ }
+ break;
- return false;
+ default:
+ assert (0);
+ break;
+ }
}
int8_t accelGetZ () {
diff --git a/accel.h b/accel.h
index 129611c..edb2540 100644
--- a/accel.h
+++ b/accel.h
@@ -12,7 +12,7 @@ typedef uint8_t horizon;
void accelInit ();
void accelStart ();
-bool accelProcess ();
+void accelProcess ();
int8_t accelGetZ ();
int8_t accelGetNormalizedZ ();
uint8_t accelGetShakeCount ();
diff --git a/gyro.c b/gyro.c
index 5b32314..cfadebf 100644
--- a/gyro.c
+++ b/gyro.c
@@ -149,11 +149,9 @@ bool gyroProcess () {
break;
case IDLE:
- if (shouldWakeup (WAKE_GYRO) && twr.status == TWST_OK) {
- /* new data available in device buffer and bus is free */
- const bool ret = twRequest (TWM_READ, L3GD20, L3GD20_OUTZ,
- (uint8_t *) &zval, sizeof (zval));
- assert (ret);
+ /* new data available in device buffer and bus is free */
+ if (shouldWakeup (WAKE_GYRO) && twRequest (TWM_READ, L3GD20,
+ L3GD20_OUTZ, (uint8_t *) &zval, sizeof (zval))) {
/* wakeup source is disabled by isr to prevent race condition */
state = READING;
}