On Fri, Dec 2, 2022 at 4:36 PM Bart Groeneveld | GPX Solutions B.V <bart@xxxxxxxx> wrote: > > From: "Bart Groeneveld | GPX Solutions B.V." <bart@xxxxxxxx> > > Not all tads have the PRW capability, which is totally OK, > according to the ACPI spec [1]: > > > _PRW is only required for devices that have the ability to wake > > the system from a system sleeping state. No, the ACPI TAD definition in Section 9.17 (ACPI 6.5) specifically requires _PRW to be present unless the system is hardware-reduced. Anyway, the RTC part can still be supported without _PRW, but then the wakeup-related attributes should not be present in such cases. > This partially solves [2] and [3]. > > [1]: https://uefi.org/sites/default/files/resources/ACPI_Spec_6_4_Jan22.pdf > [2]: https://bugzilla.kernel.org/show_bug.cgi?id=212313 > [3]: https://github.com/linux-surface/linux-surface/issues/415 > > Signed-off-by: Bart Groeneveld | GPX Solutions B.V. <bart@xxxxxxxx> > --- > drivers/acpi/acpi_tad.c | 5 ----- > 1 file changed, 5 deletions(-) > > diff --git a/drivers/acpi/acpi_tad.c b/drivers/acpi/acpi_tad.c > index e9b8e8305e23..67f71fa4362f 100644 > --- a/drivers/acpi/acpi_tad.c > +++ b/drivers/acpi/acpi_tad.c > @@ -604,11 +604,6 @@ static int acpi_tad_probe(struct platform_device *pdev) > return -ENODEV; > } > > - if (!acpi_has_method(handle, "_PRW")) { > - dev_info(dev, "Missing _PRW\n"); > - return -ENODEV; > - } > - This may be sufficient for the RTC part alone to work, but making the wakeup-related attributes available doesn't really make sense in the _PRW absent case, so they all should be made optional. > dd = devm_kzalloc(dev, sizeof(*dd), GFP_KERNEL); > if (!dd) > return -ENOMEM; > --
