rp2pio: Allow background_write(None) to terminate after complete loop

jepler · jepler · commit 1a9034ff7c3a · 2022-05-06T15:22:42.000-05:00
diff --git a/ports/raspberrypi/common-hal/rp2pio/StateMachine.c b/ports/raspberrypi/common-hal/rp2pio/StateMachine.c
@@ -917,7 +917,7 @@ bool common_hal_rp2pio_statemachine_background_write(rp2pio_statemachine_obj_t *
         self->loop = *loop;
         self->pending_buffers = pending_buffers;
 
-        if (self->dma_completed) {
+        if (self->dma_completed && self->once.info.len) {
             rp2pio_statemachine_dma_complete(self, SM_DMA_GET_CHANNEL(pio_index, sm));
             self->dma_completed = false;
         }

Original file line number	Diff line number	Diff line change
`@@ -917,7 +917,7 @@ bool common_hal_rp2pio_statemachine_background_write(rp2pio_statemachine_obj_t *`
`917`	`917`	`self->loop = *loop;`
`918`	`918`	`self->pending_buffers = pending_buffers;`
`919`	`919`
`920`		`- if (self->dma_completed) {`
	`920`	`+ if (self->dma_completed && self->once.info.len) {`
`921`	`921`	`rp2pio_statemachine_dma_complete(self, SM_DMA_GET_CHANNEL(pio_index, sm));`
`922`	`922`	`self->dma_completed = false;`
`923`	`923`	`}`