thermal/intel: Fix intel_tcc_get_temp() to support negative CPU temperature

CPU temperature can be negative in some cases. Thus the negative CPU
temperature should not be considered as a failure.

Fix intel_tcc_get_temp() and its users to support negative CPU
temperature.

Fixes: a3c1f066e1c5 ("thermal/intel: Introduce Intel TCC library")
Signed-off-by: Zhang Rui <[email protected]>
Reviewed-by: Stanislaw Gruszka <[email protected]>
Cc: 6.3+ <[email protected]> # 6.3+
Signed-off-by: Rafael J. Wysocki <[email protected]>

1 files changed, 6 insertions, 6 deletions

diff --git a/drivers/thermal/intel/intel_tcc.c b/drivers/thermal/intel/intel_tcc.c
index 2e5c741c41ca..5e8b7f34b395 100644
--- a/drivers/thermal/intel/intel_tcc.c
+++ b/drivers/thermal/intel/intel_tcc.c
@@ -103,18 +103,19 @@ EXPORT_SYMBOL_NS_GPL(intel_tcc_set_offset, INTEL_TCC);
 /**
  * intel_tcc_get_temp() - returns the current temperature
  * @cpu: cpu that the MSR should be run on, nagative value means any cpu.
+ * @temp: pointer to the memory for saving cpu temperature.
  * @pkg: true: Package Thermal Sensor. false: Core Thermal Sensor.
  *
  * Get the current temperature returned by the CPU core/package level
  * thermal sensor, in degrees C.
  *
- * Return: Temperature in degrees C on success, negative error code otherwise.
+ * Return: 0 on success, negative error code otherwise.
  */
-int intel_tcc_get_temp(int cpu, bool pkg)
+int intel_tcc_get_temp(int cpu, int *temp, bool pkg)
 {
 	u32 low, high;
 	u32 msr = pkg ? MSR_IA32_PACKAGE_THERM_STATUS : MSR_IA32_THERM_STATUS;
-	int tjmax, temp, err;
+	int tjmax, err;
 
 	tjmax = intel_tcc_get_tjmax(cpu);
 	if (tjmax < 0)
@@ -131,9 +132,8 @@ int intel_tcc_get_temp(int cpu, bool pkg)
 	if (!(low & BIT(31)))
 		return -ENODATA;
 
-	temp = tjmax - ((low >> 16) & 0x7f);
+	*temp = tjmax - ((low >> 16) & 0x7f);
 
-	/* Do not allow negative CPU temperature */
-	return temp >= 0 ? temp : -ENODATA;
+	return 0;
 }
 EXPORT_SYMBOL_NS_GPL(intel_tcc_get_temp, INTEL_TCC);