V4L/DVB (3200): Fix saa7134 ALSA/OSS collisions

- When ALSA or OSS are loaded, check if the other is present
Fixed hotplug notifiers cleanup on module removal
- The saa7134 DMA sound modules now have their own Kconfig entries, and
if built statically enforce exclusivity
- SND_PCM_OSS isn't necessary for the OSS driver

Signed-off-by: Ricardo Cerqueira <v4l@cerqueira.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>

1 files changed, 10 insertions, 3 deletions

diff --git a/drivers/media/video/saa7134/saa7134-alsa.c b/drivers/media/video/saa7134/saa7134-alsa.c
index 6752dd1c1e8..ade05f75fdb 100644
--- a/drivers/media/video/saa7134/saa7134-alsa.c
+++ b/drivers/media/video/saa7134/saa7134-alsa.c
@@ -989,6 +989,14 @@ static int saa7134_alsa_init(void)
 	struct saa7134_dev *dev = NULL;
 	struct list_head *list;
 
+	if (!dmasound_init && !dmasound_exit) {
+		dmasound_init = alsa_device_init;
+		dmasound_exit = alsa_device_exit;
+	} else {
+		printk(KERN_WARNING "saa7134 ALSA: can't load, DMA sound handler already assigned (probably to OSS)\n");
+		return -EBUSY;
+	}
+
 	printk(KERN_INFO "saa7134 ALSA driver for DMA sound loaded\n");
 
 	list_for_each(list,&saa7134_devlist) {
@@ -1001,9 +1009,6 @@ static int saa7134_alsa_init(void)
 		}
 	}
 
-	dmasound_init = alsa_device_init;
-	dmasound_exit = alsa_device_exit;
-
 	if (dev == NULL)
 		printk(KERN_INFO "saa7134 ALSA: no saa7134 cards found\n");
 
@@ -1023,6 +1028,8 @@ static void saa7134_alsa_exit(void)
 		snd_card_free(snd_saa7134_cards[idx]);
 	}
 
+	dmasound_init = NULL;
+	dmasound_exit = NULL;
 	printk(KERN_INFO "saa7134 ALSA driver for DMA sound unloaded\n");
 
 	return;