From: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date: Thu, 15 Sep 2005 16:19:00 +0000 (-0400)
Subject: [ACPI] Prefer _CST over FADT for C-state capabilities
X-Git-Tag: firefly_0821_release~39706^2~2
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6d93c64803a5fea84839789aae13290419c62d92;p=firefly-linux-kernel-4.4.55.git

[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 70d8a6ec0920..5b6a9865300e 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -690,7 +690,7 @@ static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
 
 	/* 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 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr)
 	 * 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