Commit 9121947d authored by Takashi Iwai's avatar Takashi Iwai
Browse files

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: default avatarTakashi Iwai <tiwai@suse.de>
parent d9bbb475

sound/pci/hda/hda_intel.c

+52 −2
Original line number Diff line number Diff line
@@ -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);

}

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