ALSA: oxygen: add PEX8111 initialization

Configure the PEX8111 bridge on the PCI Express cards so that the audio
DMA controller can do proper burst reads and is less likely to lose
data.  This is usually done automatically, but is required on older
cards where the user has not applied the PLX firmware update.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/oxygen/oxygen_lib.c

@@ -310,8 +310,10 @@ static void oxygen_restore_eeprom(struct oxygen *chip,
 
 static void configure_pcie_bridge(struct pci_dev *pci)
 {
-	enum { PI7C9X110 };
+	enum { PEX811X, PI7C9X110 };
 	static const struct pci_device_id bridge_ids[] = {
+		{ PCI_VDEVICE(PLX, 0x8111), .driver_data = PEX811X },
+		{ PCI_VDEVICE(PLX, 0x8112), .driver_data = PEX811X },
 		{ PCI_DEVICE(0x12d8, 0xe110), .driver_data = PI7C9X110 },
 		{ }
 	};
@@ -328,6 +330,19 @@ static void configure_pcie_bridge(struct pci_dev *pci)
 		return;
 
 	switch (id->driver_data) {
+	case PEX811X:	/* PLX PEX8111/PEX8112 PCIe/PCI bridge */
+		pci_read_config_dword(bridge, 0x48, &tmp);
+		tmp |= 1;	/* enable blind prefetching */
+		tmp |= 1 << 11;	/* enable beacon generation */
+		pci_write_config_dword(bridge, 0x48, tmp);
+
+		pci_write_config_dword(bridge, 0x84, 0x0c);
+		pci_read_config_dword(bridge, 0x88, &tmp);
+		tmp &= ~(7 << 27);
+		tmp |= 2 << 27;	/* set prefetch size to 128 bytes */
+		pci_write_config_dword(bridge, 0x88, tmp);
+		break;
+
 	case PI7C9X110:	/* Pericom PI7C9X110 PCIe/PCI bridge */
 		pci_read_config_dword(bridge, 0x40, &tmp);
 		tmp |= 1;	/* park the PCI arbiter to the sound chip */