On Wed, Nov 17, 2021 at 11:01 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
>
> Hi Rafael,
>
> Commit c10383e8ddf4 ("ACPI: scan: Release PM resources blocked by
> unused objects") adds a:
>
> bus_for_each_dev(&acpi_bus_type, NULL, NULL, acpi_dev_turn_off_if_unused);
>
> call to acpi_scan_init(). On some devices with buggy DSDTs calling
> _PS3 for one device may result in it turning off another device.
Well, I'm going to revert this commit. I'm sending a pull request
with the revert later today.
> Specifically the DSDT of the GPD win and GPD pocket devices has a
> "\\_SB_.PCI0.SDHB.BRC1" device for a non existing SDIO wifi module
> which _PS3 method sets a GPIO causing the PCI wifi card to turn off.
>
> I've an earlier, in some ways simpler, fix for this here:
> https://fedorapeople.org/~jwrdegoede/0001-ACPI-scan-Skip-turning-off-some-unused-objects-durin.patch
>
> But the sdhci-acpi.c MMC host code already has an older workaround
> for it to not toggle power on this broken ACPI object; and this
> simpler fix would require keeping that workaround. So then we would
> have 2 workarounds for the same issue in the kernel.
>
> Thus instead I've come up with a slightly different approach which
> IMHO has ended up pretty well.
>
> Patches 1-3 of this series are this different approach and assuming
> they are considered ok must be merged into 5.16 to fix the regression
> caused by commit c10383e8ddf4 on these devices.
So I'll have a look at these and if they look good, we can do that
instead of the problematic commit in 5.17.
> Patch 4 removes the now no longer necessary workaround for the same
> issue from the sdhci-acpi.c code. Once 1-3 are merged this could
> also go to 5.16 but 5.17 is fine too.
>
> Patch 5 is a small bonus cleanup to the sdhci-acpi.c code.
Thanks!
