altos: eliminate ao_wake_task

Waking up a task waiting on some random object is a bad idea. Fix
the waiters to look for suitable signalling.

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

6 files changed, 19 insertions, 26 deletions

diff --git a/src/ao.h b/src/ao.h
index 58659af5..9682e42f 100644
--- a/src/ao.h
+++ b/src/ao.h
@@ -69,10 +69,6 @@ ao_sleep(__xdata void *wchan);
 void
 ao_wakeup(__xdata void *wchan);
 
-/* Wake up a specific task */
-void
-ao_wake_task(__xdata struct ao_task *task);
-
 /* set an alarm to go off in 'delay' ticks */
 void
 ao_alarm(uint16_t delay);
diff --git a/src/ao_packet.c b/src/ao_packet.c
index 9896149c..f627e02b 100644
--- a/src/ao_packet.c
+++ b/src/ao_packet.c
@@ -117,7 +117,7 @@ ao_packet_flush(void)
 	 * then poke the master to send all queued data
 	 */
 	if (ao_packet_tx_used && ao_packet_master_sleeping)
-		ao_wake_task(&ao_packet_task);
+		ao_wakeup(&ao_packet_master_sleeping);
 }
 #endif /* PACKET_HAS_MASTER */
 
diff --git a/src/ao_packet_master.c b/src/ao_packet_master.c
index 3b23ad92..0808bc80 100644
--- a/src/ao_packet_master.c
+++ b/src/ao_packet_master.c
@@ -21,16 +21,13 @@ static char
 ao_packet_getchar(void) __critical
 {
 	char c;
-	while ((c = ao_packet_pollchar()) == AO_READ_AGAIN)
-	{
+	while ((c = ao_packet_pollchar()) == AO_READ_AGAIN) {
 		if (!ao_packet_enable)
 			break;
 		if (ao_packet_master_sleeping)
-			ao_wake_task(&ao_packet_task);
+			ao_wakeup(&ao_packet_master_sleeping);
 		ao_usb_flush();
 		ao_sleep(&ao_stdin_ready);
-		if (!ao_packet_enable)
-			break;
 	}
 	return c;
 }
@@ -41,7 +38,7 @@ ao_packet_echo(void) __reentrant
 	uint8_t	c;
 	while (ao_packet_enable) {
 		c = ao_packet_getchar();
-		if (ao_packet_enable)
+		if (c != AO_READ_AGAIN)
 			ao_usb_putchar(c);
 	}
 	ao_exit();
@@ -97,7 +94,8 @@ ao_packet_master(void)
 			if (ao_rx_packet.packet.len)
 				ao_packet_master_busy();
 			ao_packet_master_sleeping = 1;
-			ao_delay(ao_packet_master_delay);
+			ao_alarm(ao_packet_master_delay);
+			ao_sleep(&ao_packet_master_sleeping);
 			ao_packet_master_sleeping = 0;
 		}
 	}
@@ -126,8 +124,8 @@ ao_packet_forward(void) __reentrant
 		ao_delay(AO_MS_TO_TICKS(100));
 	ao_packet_enable = 0;
 	while (ao_packet_echo_task.wchan || ao_packet_task.wchan) {
-		if (ao_packet_echo_task.wchan)
-			ao_wake_task(&ao_packet_echo_task);
+		ao_radio_recv_abort();
+		ao_wakeup(&ao_stdin_ready);
 		ao_delay(AO_MS_TO_TICKS(10));
 	}
 }
diff --git a/src/ao_packet_slave.c b/src/ao_packet_slave.c
index 3040d781..39d04bbb 100644
--- a/src/ao_packet_slave.c
+++ b/src/ao_packet_slave.c
@@ -44,12 +44,13 @@ ao_packet_slave_stop(void)
 {
 	if (ao_packet_enable) {
 		ao_packet_enable = 0;
-		ao_radio_recv_abort();
 		while (ao_packet_task.wchan) {
-			ao_wake_task(&ao_packet_task);
-			ao_yield();
+			ao_radio_recv_abort();
+			ao_delay(AO_MS_TO_TICKS(10));
 		}
+		ao_radio_get();
 		ao_radio_set_telemetry();
+		ao_radio_put();
 	}
 }
 
diff --git a/src/ao_radio.c b/src/ao_radio.c
index 362b73aa..7b7c5161 100644
--- a/src/ao_radio.c
+++ b/src/ao_radio.c
@@ -377,8 +377,13 @@ ao_radio_recv(__xdata void *packet, uint8_t size) __reentrant
 			    DMA_CFG1_PRIORITY_HIGH);
 	ao_dma_start(ao_radio_dma);
 	RFST = RFST_SRX;
+
+	/* Wait for DMA to be done, for the radio receive process to
+	 * get aborted or for a receive timeout to fire
+	 */
 	__critical while (!ao_radio_dma_done && !ao_radio_abort)
-			   ao_sleep(&ao_radio_dma_done);
+			   if (ao_sleep(&ao_radio_dma_done))
+				   break;
 
 	/* If recv was aborted, clean up by stopping the DMA engine
 	 * and idling the radio
diff --git a/src/ao_task.c b/src/ao_task.c
index 72c9d7d6..35f34b49 100644
--- a/src/ao_task.c
+++ b/src/ao_task.c
@@ -204,12 +204,11 @@ ao_sleep(__xdata void *wchan)
 		ao_cur_task->wchan = wchan;
 	}
 	ao_yield();
+	ao_cur_task->alarm = 0;
 	if (ao_cur_task->wchan) {
 		ao_cur_task->wchan = NULL;
-		ao_cur_task->alarm = 0;
 		return 1;
 	}
-	ao_cur_task->alarm = 0;
 	return 0;
 }
 
@@ -234,12 +233,6 @@ ao_alarm(uint16_t delay)
 }
 
 void
-ao_wake_task(__xdata struct ao_task *task)
-{
-	task->wchan = NULL;
-}
-
-void
 ao_exit(void) __critical
 {
 	uint8_t	i;