davinci oss: improve stability for audio driver

Blocking read and write do not deadlock the OSS audio driver anymore. Still needs testing with O_NONBLOCK.

sound/oss/davinci-audio-dma-intfc.c

@@ -468,6 +468,7 @@ void audio_prime_rx(audio_state_t * state)
 	}
 	atomic_set(&is->pending_frags, is->nbfrags);
 
+	complete(&is->wfc); /* wake listeners */
 	init_completion(&is->wfc);
 	is->wfc.done = 0;
 
@@ -686,8 +687,9 @@ void audio_reset(audio_stream_t * s)
 		s->usr_head = s->dma_head;
 		atomic_set(&s->pending_frags, 0);
 
+		complete(&s->wfc); /* wake listeners */
 		init_completion(&s->wfc);
-		s->wfc.done = s->nbfrags;
+		s->wfc.done = 0; //s->nbfrags;
 	}
 	AUDIO_QUEUE_INIT(s);
 

sound/oss/davinci-audio.c

@@ -618,7 +618,7 @@ audio_read(struct file *file, char __user *buffer, size_t count, loff_t * ppos)
 			DPRINTK("AudioRead - No Memory\n");
 			return -ENOMEM;
 		}
-		audio_prime_rx(state);
+		else audio_prime_rx(state);
 	}
 
 	while (count > 0) {
@@ -756,7 +756,7 @@ audio_poll(struct file *file, struct poll_table_struct *wait)
 		if (atomic_read(&is->active) == 0) {
 			if (!is->buffers && audio_setup_buf(is))
 				return -ENOMEM;
-			audio_prime_rx(state);
+			else audio_prime_rx(state);
 		}
 		poll_wait(file, &is->wq, wait);
 	}
@@ -900,7 +900,7 @@ audio_ioctl(struct inode *inode, struct file *file, uint cmd, ulong arg)
 						FN_OUT(13);
 						return -ENOMEM;
 					}
-					audio_prime_rx(state);
+					else audio_prime_rx(state);
 				}
 				atomic_set(&is->stopped, 0);
 				audio_process_dma(is);
@@ -919,6 +919,7 @@ audio_ioctl(struct inode *inode, struct file *file, uint cmd, ulong arg)
 				if (os->mapped && !atomic_read(&os->pending_frags)) {
 					atomic_set(&os->pending_frags, os->nbfrags);
 					mutex_lock(&state->mutex);
+					complete(&os->wfc); /* wake listeners */
 					init_completion(&os->wfc);
 					os->wfc.done = 0;
 					mutex_unlock(&state->mutex);