Hi, On 4/7/21 7:50 PM, Rafael J. Wysocki wrote: > On Wed, Apr 7, 2021 at 7:43 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote: >> >> Hi, >> >> On 4/7/21 7:13 PM, Rafael J. Wysocki wrote: >>> On Tue, Apr 6, 2021 at 11:17 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote: >>>> >>>> Add a getter for the acpi_gbl_reduced_hardware variable so that modules >>>> can check if they are running on an ACPI reduced-hw platform or not. >>>> >>>> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> >>>> --- >>>> drivers/acpi/utils.c | 11 +++++++++++ >>>> include/acpi/acpi_bus.h | 1 + >>>> include/linux/acpi.h | 5 +++++ >>>> 3 files changed, 17 insertions(+) >>>> >>>> diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c >>>> index 682edd913b3b..4cb061d3169a 100644 >>>> --- a/drivers/acpi/utils.c >>>> +++ b/drivers/acpi/utils.c >>>> @@ -872,6 +872,17 @@ acpi_dev_get_first_match_dev(const char *hid, const char *uid, s64 hrv) >>>> } >>>> EXPORT_SYMBOL(acpi_dev_get_first_match_dev); >>>> >>>> +/** >>>> + * acpi_reduced_hardware - Return if this is an ACPI-reduced-hw machine >>>> + * >>>> + * Return true when running on an ACPI-reduced-hw machine, false otherwise. >>>> + */ >>>> +bool acpi_reduced_hardware(void) >>>> +{ >>>> + return acpi_gbl_reduced_hardware; >>>> +} >>>> +EXPORT_SYMBOL(acpi_reduced_hardware); >>> >>> EXPORT_SYMBOL_GPL()? >> >> Yes, that was my intention, no idea what happened here. I just prepped and send out v2 and I think I know what happened, all the other functions in drivers/acpi/utils.c are EXPORT_SYMBOL, so I probably just copy-and-pasted this without too much thinking. It might be worthwhile to see if we should also mark some other functions as EXPORT_SYMBOL_GPL() here. >> Before I send a v2, do you have any remarks on patch 2/2 (which is actually >> the more interesting patch) ? > > I thought that basing that check on the ACPICA's global variable may > be too coarse grained for some cases, but then I've decided to do it > as is now and we'll see. Yes, the whole code for selecting which backlight driver to use is mostly heuristics, so "we'll see" indeed . With that said I'm pretty confident that this change should not cause problems. Platforms which actually set acpi_gbl_reduced_hardware=true seem to be quite rare. I'm actually only aware of Bay Trail-T based devices doing this. Regards, Hans _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx