As ACPI spec said, the bit3 of the supported capabilities in _PMC indicates that the power meter supports notifications when the hardware limit is enforced. If one platform doesn't report this bit, but support hardware forced limit through some out-of-band mechanism. Driver wouldn't receive the related notifications to notify the OSPM to re-read the hardware limit. So add the print of no notifcation that hardware limit is enforced. Signed-off-by: Huisong Li <lihuisong@xxxxxxxxxx> --- drivers/hwmon/acpi_power_meter.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/hwmon/acpi_power_meter.c b/drivers/hwmon/acpi_power_meter.c index 3500859ff0bf..d3f144986fae 100644 --- a/drivers/hwmon/acpi_power_meter.c +++ b/drivers/hwmon/acpi_power_meter.c @@ -712,6 +712,10 @@ static int setup_attrs(struct acpi_power_meter_resource *resource) goto skip_unsafe_cap; } + if (resource->caps.flags & POWER_METER_CAN_NOTIFY == 0) + dev_info(&resource->acpi_dev->dev, + "no notifcation when the hardware limit is enforced.\n"); + if (resource->caps.configurable_cap) res = register_attrs(resource, rw_cap_attrs); else -- 2.22.0
