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 <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/video/saa7134/Kconfig

···
 config VIDEO_SAA7134
 	tristate "Philips SAA7134 support"
-	depends on VIDEO_DEV && PCI && I2C && SOUND && SND
+	depends on VIDEO_DEV && PCI && I2C
 	select VIDEO_BUF
 	select VIDEO_IR
 	select VIDEO_TUNER
 	select CRC32
-	select SND_PCM_OSS
 	---help---
 	  This is a video4linux driver for Philips SAA713x based
 	  TV cards.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called saa7134.
+
+config VIDEO_SAA7134_ALSA
+	tristate "Philips SAA7134 DMA audio support"
+	depends on VIDEO_SAA7134 && SOUND && SND && (!VIDEO_SAA7134_OSS || VIDEO_SAA7134_OSS = m)
+	select SND_PCM_OSS
+	---help---
+	  This is a video4linux driver for direct (DMA) audio in
+	  Philips SAA713x based TV cards using ALSA
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called saa7134-alsa.
+
+config VIDEO_SAA7134_OSS
+	tristate "Philips SAA7134 DMA audio support (OSS, DEPRECATED)"
+	depends on VIDEO_SAA7134 && SOUND_PRIME && (!VIDEO_SAA7134_ALSA || VIDEO_SAA7134_ALSA = m)
+	---help---
+	  This is a video4linux driver for direct (DMA) audio in
+	  Philips SAA713x based TV cards using OSS
+
+	  This is deprecated in favor of the ALSA module
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called saa7134-oss.
 
 config VIDEO_SAA7134_DVB
 	tristate "DVB/ATSC Support for saa7134 based TV cards"

drivers/media/video/saa7134/Makefile

···
 		saa7134-video.o saa7134-input.o
 
 obj-$(CONFIG_VIDEO_SAA7134) +=  saa7134.o saa7134-empress.o \
-				saa6752hs.o saa7134-alsa.o \
-				saa7134-oss.o
+				saa6752hs.o
+
+obj-$(CONFIG_VIDEO_SAA7134_ALSA) += saa7134-alsa.o
+obj-$(CONFIG_VIDEO_SAA7134_OSS) += saa7134-oss.o
+
 obj-$(CONFIG_VIDEO_SAA7134_DVB) += saa7134-dvb.o
 
 EXTRA_CFLAGS += -I$(src)/..

drivers/media/video/saa7134/saa7134-alsa.c

···
 	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) {
···
 			return -EBUSY;
 		}
 	}
-
-	dmasound_init = alsa_device_init;
-	dmasound_exit = alsa_device_exit;
 
 	if (dev == NULL)
 		printk(KERN_INFO "saa7134 ALSA: no saa7134 cards found\n");
···
 		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;

drivers/media/video/saa7134/saa7134-oss.c

···
 	struct saa7134_dev *dev = NULL;
 	struct list_head *list;
 
+	if (!dmasound_init && !dmasound_exit) {
+		dmasound_init = oss_device_init;
+		dmasound_exit = oss_device_exit;
+	} else {
+		printk(KERN_WARNING "saa7134 OSS: can't load, DMA sound handler already assigned (probably to ALSA)\n");
+		return -EBUSY;
+	}
+
 	printk(KERN_INFO "saa7134 OSS driver for DMA sound loaded\n");
+
 
 	list_for_each(list,&saa7134_devlist) {
 		dev = list_entry(list, struct saa7134_dev, devlist);
···
 
 	if (dev == NULL)
 		printk(KERN_INFO "saa7134 OSS: no saa7134 cards found\n");
-
-	dmasound_init = oss_device_init;
-	dmasound_exit = oss_device_exit;
 
 	return 0;
 
···
 		oss_device_exit(dev);
 
 	}
+
+	dmasound_init = NULL;
+	dmasound_exit = NULL;
 
 	printk(KERN_INFO "saa7134 OSS driver for DMA sound unloaded\n");