ALSA: jazz16: refine dma and irq selection

Narrow the dma and irq selection after the DOS driver.

Add ALSA configuration description as well.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/isa/sb/jazz16.c b/sound/isa/sb/jazz16.c
index d52966b..8d21a3f 100644
--- a/sound/isa/sb/jazz16.c
+++ b/sound/isa/sb/jazz16.c
@@ -189,10 +189,29 @@
 	if (port[dev] == SNDRV_AUTO_PORT) {
 		snd_printk(KERN_ERR "please specify port\n");
 		return 0;
+	} else if (port[dev] == 0x200 || (port[dev] & ~0x270)) {
+		snd_printk(KERN_ERR "incorrect port specified\n");
+		return 0;
+	}
+	if (dma8[dev] != SNDRV_AUTO_DMA &&
+	    dma8[dev] != 1 && dma8[dev] != 3) {
+		snd_printk(KERN_ERR "dma8 must be 1 or 3\n");
+		return 0;
 	}
 	if (dma16[dev] != SNDRV_AUTO_DMA &&
 	    dma16[dev] != 5 && dma16[dev] != 7) {
-		snd_printk(KERN_ERR "dma16 must be 5 or 7");
+		snd_printk(KERN_ERR "dma16 must be 5 or 7\n");
+		return 0;
+	}
+	if (mpu_port[dev] != SNDRV_AUTO_PORT &&
+	    (mpu_port[dev] & ~0x030) != 0x300) {
+		snd_printk(KERN_ERR "incorrect mpu_port specified\n");
+		return 0;
+	}
+	if (mpu_irq[dev] != SNDRV_AUTO_DMA &&
+	    mpu_irq[dev] != 2 && mpu_irq[dev] != 3 &&
+	    mpu_irq[dev] != 5 && mpu_irq[dev] != 7) {
+		snd_printk(KERN_ERR "mpu_irq must be 2, 3, 5 or 7\n");
 		return 0;
 	}
 	return 1;