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authorZhang Rui <rui.zhang@intel.com>2012-11-27 23:42:11 +0400
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2012-11-27 23:42:11 +0400
commit261cba2deb7d3bebd180c35d5dbf8961f6e9afc4 (patch)
tree60a9d395401edc63011f7c1ce7f1ddedb04895df /drivers/acpi/thermal.c
parent05bce79e6d24ee6eb2beddf0f6314358404d472f (diff)
downloadlinux-261cba2deb7d3bebd180c35d5dbf8961f6e9afc4.tar.xz
ACPI / thermal: _TMP and _CRT/_HOT/_PSV/_ACx dependency fix
On some platforms, _TMP and _CRT/_HOT/_PSV/_ACx have dependency. And there is no way for OS to detect this dependency. commit 9bcb8118965ab4631a65ee0726e6518f75cda6c5 shows us a problem that _TMP must be evaluate after _CRT/_HOT/_PSV/_ACx, or else firmware will shutdown the system. But the machine in https://bugzilla.kernel.org/show_bug.cgi?id=43284 shows us that _PSV would return valid value only if _TMP has been evaluated once. With this patch, all of the control methods will be evaluated once, in the _CRT/_HOT/_PSV/_CRT/_TMP order, before they are actually used. [rjw: Added a local variable for the handle and modified the loop slightly.] Signed-off-by: Zhang Rui <rui.zhang@intel.com> Tested-by: katabami <katabami@lavabit.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/thermal.c')
-rw-r--r--drivers/acpi/thermal.c34
1 files changed, 34 insertions, 0 deletions
diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index 804204d41999..6e8cc16b54c1 100644
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -984,6 +984,38 @@ static void acpi_thermal_notify(struct acpi_device *device, u32 event)
}
}
+/*
+ * On some platforms, the AML code has dependency about
+ * the evaluating order of _TMP and _CRT/_HOT/_PSV/_ACx.
+ * 1. On HP Pavilion G4-1016tx, _TMP must be invoked after
+ * /_CRT/_HOT/_PSV/_ACx, or else system will be power off.
+ * 2. On HP Compaq 6715b/6715s, the return value of _PSV is 0
+ * if _TMP has never been evaluated.
+ *
+ * As this dependency is totally transparent to OS, evaluate
+ * all of them once, in the order of _CRT/_HOT/_PSV/_ACx,
+ * _TMP, before they are actually used.
+ */
+static void acpi_thermal_aml_dependency_fix(struct acpi_thermal *tz)
+{
+ acpi_handle handle = tz->device->handle;
+ unsigned long long value;
+ int i;
+
+ acpi_evaluate_integer(handle, "_CRT", NULL, &value);
+ acpi_evaluate_integer(handle, "_HOT", NULL, &value);
+ acpi_evaluate_integer(handle, "_PSV", NULL, &value);
+ for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
+ char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
+ acpi_status status;
+
+ status = acpi_evaluate_integer(handle, name, NULL, &value);
+ if (status == AE_NOT_FOUND)
+ break;
+ }
+ acpi_evaluate_integer(handle, "_TMP", NULL, &value);
+}
+
static int acpi_thermal_get_info(struct acpi_thermal *tz)
{
int result = 0;
@@ -992,6 +1024,8 @@ static int acpi_thermal_get_info(struct acpi_thermal *tz)
if (!tz)
return -EINVAL;
+ acpi_thermal_aml_dependency_fix(tz);
+
/* Get trip points [_CRT, _PSV, etc.] (required) */
result = acpi_thermal_get_trip_points(tz);
if (result)