ALSA CVS update

D:2003/08/28 16:07:26
C:Documentation,VIA82xx driver
A:Takashi Iwai <tiwai@suse.de>
F:Documentation/ALSA-Configuration.txt:1.16->1.17 
F:pci/via82xx.c:1.47->1.48 
L:- added the check of DXS supports (so far, empty).
L:  the default value of dxs_support is again 0.
L:- fixed the description.

Documentation/sound/alsa/ALSA-Configuration.txt

@@ -992,8 +992,8 @@ Module parameters
 		  [VIA686A/686B only]
     ac97_clock	- AC'97 codec clock base (default 48000Hz)
     dxs_support	- support DXS channels,
-		  0 = auto, 1 = enable, 2 = disable,
-		  3 = 48k only (default)
+		  0 = auto (defalut), 1 = enable, 2 = disable,
+		  3 = 48k only
 		  [VIA8233/C,8235 only]
 
     Module supports autoprobe and multiple bus-master chips (max 8).
@@ -1005,11 +1005,15 @@ Module parameters
           assigned under 15. You might also upgrade your BIOS.
     
     Note: VIA8233/5 (not VIA8233A) can support DXS (direct sound)
-	  channels as the first PCM.  With this device, up to 4
-	  streams can be played at the same time.  On some motherboards,
-	  these channels don't work properly except for 48k due to the
-	  bug of BIOS.  For supporting other sample rates, try to
-	  specify dxs_support=0.
+	  channels as the first PCM.  On these channels, up to 4
+	  streams can be played at the same time.
+	  As default (dxs_support = 0), 48k fixed rate is chosen since
+	  the output is often noisy except for 48k on some mother
+	  boards due to the bug of BIOS.
+	  Please try once dxs_support=1 and if it works on other
+	  sample rates, please let us know the PCI subsystem
+	  vendor/device id's (output of "lspci -nv").
+	  If it doesn't work, use dxs_support=3 or dxs_support=2.
 
     Note: for the MPU401 on VIA823x, use snd-mpu401 driver
 	  additonally.  The mpu_port option is for VIA686 chips only.

sound/pci/via82xx.c

@@ -74,7 +74,7 @@ static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
 static int enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;	/* Enable this card */
 static long mpu_port[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = -1};
 static int ac97_clock[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 48000};
-static int dxs_support[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 3};
+static int dxs_support[SNDRV_CARDS];
 
 MODULE_PARM(index, "1-" __MODULE_STRING(SNDRV_CARDS) "i");
 MODULE_PARM_DESC(index, "Index value for VIA 82xx bridge.");
@@ -283,6 +283,15 @@ DEFINE_VIA_REGSET(CAPTURE_8233, 0x60);
 #define  VIA8233_SPDIF_SLOT_78		0x02
 #define  VIA8233_SPDIF_SLOT_69		0x03
 
+/*
+ */
+
+#define VIA_DXS_AUTO	0
+#define VIA_DXS_ENABLE	1
+#define VIA_DXS_DISABLE	2
+#define VIA_DXS_48K	3
+
+
 /*
  */
 
@@ -1944,6 +1953,41 @@ static struct via823x_info via823x_cards[] __devinitdata = {
 	{ VIA_REV_8235, "VIA 8235", TYPE_VIA8233 },
 };
 
+/*
+ * auto detection of DXS channel supports.
+ */
+struct dxs_whitelist {
+	unsigned short vendor;
+	unsigned short device; 
+	int action;	/* new dxs_support value */
+};
+
+static int __devinit check_dxs_list(struct pci_dev *pci)
+{
+	static struct dxs_whitelist whitelist[] = {
+		// { .vendor = xxxx, .device = yyyy, .action = x },
+		{ } /* terminator */
+	};
+	struct dxs_whitelist *w;
+	unsigned short subsystem_vendor;
+	unsigned short subsystem_device;
+
+	pci_read_config_word(pci, PCI_SUBSYSTEM_VENDOR_ID, &subsystem_vendor);
+	pci_read_config_word(pci, PCI_SUBSYSTEM_ID, &subsystem_device);
+
+	for (w = whitelist; w->vendor; w++)
+		if (w->vendor == subsystem_vendor &&
+		    w->device == subsystem_device)
+			return w->action;
+
+	/*
+	 * not detected, try 48k rate only to be sure.
+	 */
+	printk(KERN_INFO "via82xx: Assuming DXS channels with 48k fixed sample rate.\n");
+	printk(KERN_INFO "         Please try dxs_support=1 option and report if it works on your machine.\n");
+	return VIA_DXS_48K;
+};
+
 static int __devinit snd_via82xx_probe(struct pci_dev *pci,
 				       const struct pci_device_id *pci_id)
 {
@@ -1984,13 +2028,16 @@ static int __devinit snd_via82xx_probe(struct pci_dev *pci,
 				break;
 			}
 		}
+		if (dxs_support[dev] == VIA_DXS_AUTO)
+			dxs_support[dev] = check_dxs_list(pci);
 		/* force to use VIA8233 or 8233A model according to
 		 * dxs_support module option
 		 */
-		if (dxs_support[dev] == 1)
-			chip_type = TYPE_VIA8233;
-		else if (dxs_support[dev] == 2)
+		if (dxs_support[dev] == VIA_DXS_DISABLE)
 			chip_type = TYPE_VIA8233A;
+		else
+			chip_type = TYPE_VIA8233;
+
 		if (chip_type == TYPE_VIA8233A)
 			strcpy(card->driver, "VIA8233A");
 		else