ALSA: hda - Check the dead HDMI audio controller by vga-switcheroo

When a discrete-GPU is disabled by the VGA switcheroo, the
corresponding HD-audio controller for HDMI output is also disabled.
Such a dead controller still appears in the PCI device list, but you
can't access properly any longer (even calling pci_read_config_*()
triggers Oops!) which leads the stall of the whole communication of
the driver.

This patch adds a check of graphics controller at the probe time to
see whether it's disabled by vga-switcheroo.  If disabled, skip the
whole initialization of this controller.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=43155

Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Iwai 2012-04-26 12:13:25 +02:00
parent d9bbb4756d
commit 9121947d69

View file

@ -53,6 +53,7 @@
#endif
#include <sound/core.h>
#include <sound/initval.h>
#include <linux/vgaarb.h>
#include "hda_codec.h"
@ -2493,6 +2494,45 @@ static int azx_dev_free(struct snd_device *device)
return azx_free(device->device_data);
}
/*
* Check of disabled HDMI controller by vga-switcheroo
*/
static struct pci_dev __devinit *get_bound_vga(struct pci_dev *pci)
{
struct pci_dev *p;
/* check only discrete GPU */
switch (pci->vendor) {
case PCI_VENDOR_ID_ATI:
case PCI_VENDOR_ID_AMD:
case PCI_VENDOR_ID_NVIDIA:
if (pci->devfn == 1) {
p = pci_get_domain_bus_and_slot(pci_domain_nr(pci->bus),
pci->bus->number, 0);
if (p) {
if ((p->class >> 8) == PCI_CLASS_DISPLAY_VGA)
return p;
pci_dev_put(p);
}
}
break;
}
return NULL;
}
static bool __devinit check_hdmi_disabled(struct pci_dev *pci)
{
bool vga_inactive = false;
struct pci_dev *p = get_bound_vga(pci);
if (p) {
if (vga_default_device() && p != vga_default_device())
vga_inactive = true;
pci_dev_put(p);
}
return vga_inactive;
}
/*
* white/black-listing for position_fix
*/
@ -2928,6 +2968,12 @@ static int __devinit azx_probe(struct pci_dev *pci,
return -ENOENT;
}
if (check_hdmi_disabled(pci)) {
snd_printk(KERN_INFO SFX
"Inactive VGA controller; disabled audio, too\n");
goto out;
}
err = snd_card_create(index[dev], id[dev], THIS_MODULE, 0, &card);
if (err < 0) {
snd_printk(KERN_ERR SFX "Error creating card!\n");
@ -2984,8 +3030,10 @@ static int __devinit azx_probe(struct pci_dev *pci,
power_down_all_codecs(chip);
azx_notifier_register(chip);
out:
dev++;
return err;
return 0;
out_free:
snd_card_free(card);
return err;
@ -2993,7 +3041,9 @@ out_free:
static void __devexit azx_remove(struct pci_dev *pci)
{
snd_card_free(pci_get_drvdata(pci));
struct snd_card *card = pci_get_drvdata(pci);
if (card)
snd_card_free(card);
pci_set_drvdata(pci, NULL);
}