ACPI: Evaluate thermal trip points before reading temperature

Commit Message

Matthew Garrett Aug. 29, 2011, 1:33 p.m. UTC

An HP laptop (Pavilion G4-1016tx) has the following code in _TMP:

       Store (\_SB.PCI0.LPCB.EC0.RTMP, Local0)
       If (LGreaterEqual (Local0, S4TP))
       {
           Store (One, HTS4)
       }

S4TP is initialised at 0 and not programmed further until either _HOT or
_CRT is called. If we evaluate _TMP before the trip points then HTS4 will
always be set, causing the firmware to generate a message on boot
complaining that the system shut down because of overheating. The simplest
solution is just to reverse the checking of trip points and _TMP in thermal
init.

Signed-off-by: Matthew Garrett <[e-mail]>
---
 drivers/acpi/thermal.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

Patch

diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index 48fbc64..7dbebea 100644
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -941,13 +941,13 @@  static int acpi_thermal_get_info(struct acpi_thermal *tz)
 	if (!tz)
 		return -EINVAL;
 
-	/* Get temperature [_TMP] (required) */
-	result = acpi_thermal_get_temperature(tz);
+	/* Get trip points [_CRT, _PSV, etc.] (required) */
+	result = acpi_thermal_get_trip_points(tz);
 	if (result)
 		return result;
 
-	/* Get trip points [_CRT, _PSV, etc.] (required) */
-	result = acpi_thermal_get_trip_points(tz);
+	/* Get temperature [_TMP] (required) */
+	result = acpi_thermal_get_temperature(tz);
 	if (result)
 		return result;