thermal fixup for broken BIOS which has invalid trip points.

ACPI thermal driver only re-evaluate valid trip points.
For the broken BIOS show in
http://bugzilla.kernel.org/show_bug.cgi?id=8544
the active[0] is set to invalid at boot time
and it will not be re-evaluated again.
We can still get a warning message at boot time.

http://marc.info/?l=linux-kernel&m=120496222629983&w=2

Signed-off-by: Zhang Rui<rui.zhang@intel.com>
---
 drivers/acpi/thermal.c |   16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

Index: linux-2.6/drivers/acpi/thermal.c
===================================================================
--- linux-2.6.orig/drivers/acpi/thermal.c
+++ linux-2.6/drivers/acpi/thermal.c
@@ -401,7 +401,8 @@ static int acpi_thermal_trips_update(str
 	}
 
 	/* Passive (optional) */
-	if (flag & ACPI_TRIPS_PASSIVE) {
+	if (((flag & ACPI_TRIPS_PASSIVE) && tz->trips.passive.flags.valid) ||
+		(flag == ACPI_TRIPS_INIT)) {
 		valid = tz->trips.passive.flags.valid;
 		if (psv == -1) {
 			status = AE_SUPPORT;
@@ -440,8 +441,11 @@ static int acpi_thermal_trips_update(str
 		memset(&devices, 0, sizeof(struct acpi_handle_list));
 		status = acpi_evaluate_reference(tz->device->handle, "_PSL",
 							NULL, &devices);
-		if (ACPI_FAILURE(status))
+		if (ACPI_FAILURE(status)) {
+			printk(KERN_WARNING PREFIX
+				"Invalid passive threshold\n");
 			tz->trips.passive.flags.valid = 0;
+		}
 		else
 			tz->trips.passive.flags.valid = 1;
 
@@ -465,7 +469,8 @@ static int acpi_thermal_trips_update(str
 		if (act == -1)
 			break; /* disable all active trip points */
 
-		if (flag & ACPI_TRIPS_ACTIVE) {
+		if ((flag == ACPI_TRIPS_INIT) || ((flag & ACPI_TRIPS_ACTIVE) &&
+			tz->trips.active[i].flags.valid)) {
 			status = acpi_evaluate_integer(tz->device->handle,
 				name, NULL, &tz->trips.active[i].temperature);
 			if (ACPI_FAILURE(status)) {
@@ -497,8 +502,11 @@ static int acpi_thermal_trips_update(str
 			memset(&devices, 0, sizeof(struct acpi_handle_list));
 			status = acpi_evaluate_reference(tz->device->handle,
 						name, NULL, &devices);
-			if (ACPI_FAILURE(status))
+			if (ACPI_FAILURE(status)) {
+				printk(KERN_WARNING PREFIX
+					"Invalid active%d threshold\n", i);
 				tz->trips.active[i].flags.valid = 0;
+			}
 			else
 				tz->trips.active[i].flags.valid = 1;