Re: [PATCH 1/3] ACPI: processor: idle: Relocate and verify acpi_processor_ffh_lpi_probe

From: Rafael J. Wysocki

Date: Thu Jan 15 2026 - 08:06:25 EST


On Thu, Jan 15, 2026 at 1:09 PM lihuisong (C) <lihuisong@xxxxxxxxxx> wrote:
>
> Hi Rafael,
>
> On 1/15/2026 1:27 AM, Rafael J. Wysocki wrote:
> > On Tue, Nov 25, 2025 at 7:52 AM Huisong Li <lihuisong@xxxxxxxxxx> wrote:
> >> The platform used LPI need check if the LPI support and the entry
> >> method is valid by the acpi_processor_ffh_lpi_probe(). But the return
> >> of acpi_processor_ffh_lpi_probe() in acpi_processor_setup_cpuidle_dev()
> >> isn't verified by any caller.
> >>
> >> What's more, acpi_processor_get_power_info() is a more logical place for
> >> verifying the validity of FFH LPI than acpi_processor_setup_cpuidle_dev().
> >> So move acpi_processor_ffh_lpi_probe() from the latter to the former and
> >> verify its return.
> >>
> >> Signed-off-by: Huisong Li <lihuisong@xxxxxxxxxx>
> >> ---
> >> drivers/acpi/processor_idle.c | 10 ++++++++--
> >> 1 file changed, 8 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
> >> index 5f86297c8b23..cdf86874a87a 100644
> >> --- a/drivers/acpi/processor_idle.c
> >> +++ b/drivers/acpi/processor_idle.c
> >> @@ -1252,7 +1252,7 @@ static int acpi_processor_setup_cpuidle_dev(struct acpi_processor *pr,
> >>
> >> dev->cpu = pr->id;
> >> if (pr->flags.has_lpi)
> >> - return acpi_processor_ffh_lpi_probe(pr->id);
> >> + return 0;
> >>
> >> acpi_processor_setup_cpuidle_cx(pr, dev);
> >> return 0;
> >> @@ -1264,7 +1264,13 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr)
> >>
> >> ret = acpi_processor_get_lpi_info(pr);
> >> if (ret)
> >> - ret = acpi_processor_get_cstate_info(pr);
> >> + return acpi_processor_get_cstate_info(pr);
> >> +
> >> + if (pr->flags.has_lpi) {
> >> + ret = acpi_processor_ffh_lpi_probe(pr->id);
> >> + if (ret)
> >> + pr_err("Processor FFH LPI state is invalid.\n");
> >> + }
> >>
> >> return ret;
> >> }
> >> --
> > Please reorder this behind the next patch in the series.
> Patch 2/3 depends on this patch.
> So I don't know how to reorder this patch.

I should have been more precise, sorry.

Please first convert acpi_processor_setup_cpuidle_dev() to a void
function and then make the changes from this patch on top of that.