sound: oxygen: fix for PI7C9X110 compatibility
If the card is used with a Pericom PI7C9X110 PCI-E/PCI bridge,
reconfigure the latter's PCI buffering to fix an unknown problem.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/oxygen/oxygen_lib.c b/sound/pci/oxygen/oxygen_lib.c
index c9f2714..9c5e645 100644
--- a/sound/pci/oxygen/oxygen_lib.c
+++ b/sound/pci/oxygen/oxygen_lib.c
@@ -307,6 +307,28 @@
}
}
+static void pci_bridge_magic(void)
+{
+ struct pci_dev *pci = NULL;
+ u32 tmp;
+
+ for (;;) {
+ /* If there is any Pericom PI7C9X110 PCI-E/PCI bridge ... */
+ pci = pci_get_device(0x12d8, 0xe110, pci);
+ if (!pci)
+ break;
+ /*
+ * ... configure its secondary internal arbiter to park to
+ * the secondary port, instead of to the last master.
+ */
+ if (!pci_read_config_dword(pci, 0x40, &tmp)) {
+ tmp |= 1;
+ pci_write_config_dword(pci, 0x40, tmp);
+ }
+ /* Why? Try asking C-Media. */
+ }
+}
+
static void oxygen_init(struct oxygen *chip)
{
unsigned int i;
@@ -585,6 +607,7 @@
snd_card_set_dev(card, &pci->dev);
card->private_free = oxygen_card_free;
+ pci_bridge_magic();
oxygen_init(chip);
chip->model.init(chip);