Comment 44 for bug 1094800

Greetings, I also hit this issue on the recently released Toshiva Kirabook. I bisected the v3.3->v3.4 change (with the help of patching in the kvm clock fix as needed) and tracked it down to this commit:

commit 2feec47d4c5f80b05f1650f5a24865718978eea4
Author: Bob Moore <email address hidden>
Date: Tue Feb 14 15:00:53 2012 +0800

    ACPICA: ACPI 5: Support for new FADT SleepStatus, SleepControl registers

    Adds sleep and wake support for systems with these registers.
    One new file, hwxfsleep.c

    Signed-off-by: Bob Moore <email address hidden>
    Signed-off-by: Len Brown <email address hidden>

Specifically, when the sleep status/control registeres are detected they are used instead of the traditional registers. The failure to resume a second time is triggered by this write in the new acpi_hw_extended_wake_prep function:

    status = acpi_get_sleep_type_data(ACPI_STATE_S0,
                      &acpi_gbl_sleep_type_a,
                      &acpi_gbl_sleep_type_b);
    if (ACPI_SUCCESS(status)) {
        sleep_type_value =
            ((acpi_gbl_sleep_type_a << ACPI_X_SLEEP_TYPE_POSITION) &
             ACPI_X_SLEEP_TYPE_MASK);

        (void)acpi_write((u64)(sleep_type_value | ACPI_X_SLEEP_ENABLE),
                 &acpi_gbl_FADT.sleep_control);
    }

Replacing that write with the corresponding code from acpi_hw_legacy_wake_prep while leaving the other acpi_hw_extended_* functions alone gets suspend/resume working consistantly. That isn't quite enough as events don't seem to get re-enabled so acpi buttons and such don't work after resume. Copying the enable power button code from acpi_hw_legacy_wake to acpi_hw_extended_wake at least gets the power button back but lid, brightness, etc remain dead.

At the moment I've hacked these changes into v3.10.0-rc2 along with another hack to fix a video regression and it seems to behave reasonabley well. I'm not sure what the apropriate fix is, maybe a blacklist of devices that provide the new registers but don't implement them properly? I'll also post this to the linux-acpi list to see if anyone there offers advice.