Ubuntu
linux-source-2.6.22 package

  1. Bug #78257
  2. Comment #24

Comment 24 for bug 78257

Revision history for this message
TJ (tj) wrote : Re: Intel HDA busted following resume from suspend (No sound after computer exits standby)

Same symptoms on Gutsy Tribe-5 32-bit with Intel ICH7. No indications as to whether the cause is the same.

On Gutsy Tribe-5 after resume the PCI config registers are incorrectly set-up so the hardware is in AC'97 mode, not HDA. Although the register affected here is HDCTRL (0x40) this has similarities with bug #100114.

Before Suspend HDCTL = 0x03 (HDA mode, BITCLK not toggling)

After Resume HDCTL = 0x00 (AC'97 mode, BITCLK toggling)

Use this command to examine the config registers (you may need to adjust the path if your sound device has a different address)

$ sudo dd if=/sys/bus/pci/devices/0000\:00\:1b.0/config | hexdump -C

As in bug #100114 I created a script to correct this config register issue. The script is attached. This doesn't solve the lack of sound but goes some way to indicating where the problem lies.

Assigning to ACPI Kernel Team and actively working on it.