Subject: Fix broken suspend/resume in ohci1394 (Was: ACPI suspend problems revisited) From: Robert Hancock I've been experimenting to track down the cause of suspend/resume problems on my Compaq Presario X1050 laptop: http://bugzilla.kernel.org/show_bug.cgi?id=6075 Essentially the ACPI Embedded Controller and keyboard controller would get into a bizarre, confused state after resume. I found that unloading the ohci1394 module before suspend and reloading it after resume made the problem go away. Diffing the dmesg output from resume, with and without the module loaded, I found that with the module loaded I was missing these: PM: Writing back config space on device 0000:02:00.0 at offset 1. (Was 2100080, writing 2100007) PM: Writing back config space on device 0000:02:00.0 at offset 3. (Was 0, writing 8008) PM: Writing back config space on device 0000:02:00.0 at offset 4. (Was 0, writing 90200000) PM: Writing back config space on device 0000:02:00.0 at offset 5. (Was 1, writing 2401) PM: Writing back config space on device 0000:02:00.0 at offset f. (Was 20000100, writing 2000010a) The default PCI driver performs the pci_restore_state when no driver is loaded for the device. When the ohci1394 driver is loaded, it is supposed to do this, however it appears not to do so. I created the patch below and tested it, and it appears to resolve the suspend problems I was having with the module loaded. I only added in the pci_save_state and pci_restore_state - however, though I know little of this hardware, surely the driver should really be doing more than this when suspending and resuming? Currently it does almost nothing, what if there are commands in progress, etc? Signed-off-by: Robert Hancock Cc: Jody McIntyre Cc: Ben Collins Cc: Greg KH Signed-off-by: Andrew Morton --- drivers/ieee1394/ohci1394.c | 3 +++ 1 files changed, 3 insertions(+) diff -puN drivers/ieee1394/ohci1394.c~fix-broken-suspend-resume-in-ohci1394-was-acpi-suspend drivers/ieee1394/ohci1394.c --- devel/drivers/ieee1394/ohci1394.c~fix-broken-suspend-resume-in-ohci1394-was-acpi-suspend 2006-05-22 17:03:36.000000000 -0700 +++ devel-akpm/drivers/ieee1394/ohci1394.c 2006-05-22 17:03:36.000000000 -0700 @@ -3540,6 +3540,7 @@ static int ohci1394_pci_resume (struct p } #endif /* CONFIG_PPC_PMAC */ + pci_restore_state(pdev); pci_enable_device(pdev); return 0; @@ -3559,6 +3560,8 @@ static int ohci1394_pci_suspend (struct } #endif + pci_save_state(pdev); + return 0; } _