[ACPI] Prefer _CST over FADT for C-state capabilities
Note: This ACPI standard compliance may cause regression
on some system, if they have _CST present, but _CST value
is bogus. "nocst" module parameter should workaround
that regression.
http://bugzilla.kernel.org/show_bug.cgi?id=5165
Signed-off-by: Venkatesh Pallipadi<venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
(cherry picked from 883baf7f7e81cca26f4683ae0d25ba48f094cc08 commit)
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 70d8a6e..5b6a986 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -690,7 +690,7 @@
/* Validate number of power states discovered */
if (pr->power.count < 2)
- status = -ENODEV;
+ status = -EFAULT;
end:
acpi_os_free(buffer.pointer);
@@ -841,11 +841,11 @@
* this function */
result = acpi_processor_get_power_info_cst(pr);
- if ((result) || (acpi_processor_power_verify(pr) < 2)) {
+ if (result == -ENODEV)
result = acpi_processor_get_power_info_fadt(pr);
- if ((result) || (acpi_processor_power_verify(pr) < 2))
- result = acpi_processor_get_power_info_default_c1(pr);
- }
+
+ if ((result) || (acpi_processor_power_verify(pr) < 2))
+ result = acpi_processor_get_power_info_default_c1(pr);
/*
* Set Default Policy