ACPI: thermal_lib: Add functions returning temperature in deci-Kelvin

Because the ACPI thermal driver generally operates temperature values
in deci-Kelvin, it needs the library functions returning temperature
for various trip point types to use deci-Kelvin too.

To address that, arrange the ACPI thermal library code in three levels
of functions where the high-level ones will return temperature in
milli-Celsius, as needed by the thermal core and the majority of
thermal drivers, the mid-level ones will return temperature in
deci-Kelvin and will be called internally by the corresponding high-
level functions, and all of the mid-level functions will call the same
low-level one, acpi_trip_temp(), to actually evaluate ACPI objects to
retrieve themperature values from the platform firmware.

Going forward, this will allow the ACPI thermal driver to use the
mid-level functions to provide temperature values needed by it, so as
to reduce code duplication related to evaluating trip temperature ACPI
control methods.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/thermal_lib.c b/drivers/acpi/thermal_lib.c
index 43eaf0f2ff49bec0001da8271743c862ade214ca..02bf570141af7d7ddd9980d89ac0574f7cbf2c7d 100644 (file)
--- a/drivers/acpi/thermal_lib.c
+++ b/drivers/acpi/thermal_lib.c
@@ -3,8 +3,8 @@
  * Copyright 2023 Linaro Limited
  * Copyright 2023 Intel Corporation
  *
- * Library routines for populating a generic thermal trip point structure
- * with data obtained by evaluating a specific object in the ACPI Namespace.
+ * Library routines for retrieving trip point temperature values from the
+ * platform firmware via ACPI.
  */
 #include <linux/acpi.h>
 #include <linux/units.h>
@@ -17,11 +17,11 @@
  * firmware. Any values out of these boundaries may be considered
  * bogus and we can assume the firmware has no data to provide.
  */
-#define TEMP_MIN_DECIK 2180
-#define TEMP_MAX_DECIK 4480
+#define TEMP_MIN_DECIK 2180ULL
+#define TEMP_MAX_DECIK 4480ULL
 
-static int thermal_acpi_trip_temp(struct acpi_device *adev, char *obj_name,
-                                 int *ret_temp)
+static int acpi_trip_temp(struct acpi_device *adev, char *obj_name,
+                         int *ret_temp)
 {
        unsigned long long temp;
        acpi_status status;
@@ -33,7 +33,7 @@ static int thermal_acpi_trip_temp(struct acpi_device *adev, char *obj_name,
        }
 
        if (temp >= TEMP_MIN_DECIK && temp <= TEMP_MAX_DECIK) {
-               *ret_temp = deci_kelvin_to_millicelsius(temp);
+               *ret_temp = temp;
        } else {
                acpi_handle_debug(adev->handle, "%s result %llu out of range\n",
                                  obj_name, temp);
@@ -43,6 +43,44 @@ static int thermal_acpi_trip_temp(struct acpi_device *adev, char *obj_name,
        return 0;
 }
 
+int acpi_active_trip_temp(struct acpi_device *adev, int id, int *ret_temp)
+{
+       char obj_name[] = {'_', 'A', 'C', '0' + id, '\0'};
+
+       if (id < 0 || id > 9)
+               return -EINVAL;
+
+       return acpi_trip_temp(adev, obj_name, ret_temp);
+}
+
+int acpi_passive_trip_temp(struct acpi_device *adev, int *ret_temp)
+{
+       return acpi_trip_temp(adev, "_PSV", ret_temp);
+}
+
+int acpi_hot_trip_temp(struct acpi_device *adev, int *ret_temp)
+{
+       return acpi_trip_temp(adev, "_HOT", ret_temp);
+}
+
+int acpi_critical_trip_temp(struct acpi_device *adev, int *ret_temp)
+{
+       return acpi_trip_temp(adev, "_CRT", ret_temp);
+}
+
+static int thermal_temp(int error, int temp_decik, int *ret_temp)
+{
+       if (error)
+               return error;
+
+       if (temp_decik == THERMAL_TEMP_INVALID)
+               *ret_temp = THERMAL_TEMP_INVALID;
+       else
+               *ret_temp = deci_kelvin_to_millicelsius(temp_decik);
+
+       return 0;
+}
+
 /**
  * thermal_acpi_active_trip_temp - Retrieve active trip point temperature
  * @adev: Target thermal zone ACPI device object.
@@ -57,12 +95,10 @@ static int thermal_acpi_trip_temp(struct acpi_device *adev, char *obj_name,
  */
 int thermal_acpi_active_trip_temp(struct acpi_device *adev, int id, int *ret_temp)
 {
-       char obj_name[] = {'_', 'A', 'C', '0' + id, '\0'};
-
-       if (id < 0 || id > 9)
-               return -EINVAL;
+       int temp_decik;
+       int ret = acpi_active_trip_temp(adev, id, &temp_decik);
 
-       return thermal_acpi_trip_temp(adev, obj_name, ret_temp);
+       return thermal_temp(ret, temp_decik, ret_temp);
 }
 EXPORT_SYMBOL_GPL(thermal_acpi_active_trip_temp);
 
@@ -78,7 +114,10 @@ EXPORT_SYMBOL_GPL(thermal_acpi_active_trip_temp);
  */
 int thermal_acpi_passive_trip_temp(struct acpi_device *adev, int *ret_temp)
 {
-       return thermal_acpi_trip_temp(adev, "_PSV", ret_temp);
+       int temp_decik;
+       int ret = acpi_passive_trip_temp(adev, &temp_decik);
+
+       return thermal_temp(ret, temp_decik, ret_temp);
 }
 EXPORT_SYMBOL_GPL(thermal_acpi_passive_trip_temp);
 
@@ -95,7 +134,10 @@ EXPORT_SYMBOL_GPL(thermal_acpi_passive_trip_temp);
  */
 int thermal_acpi_hot_trip_temp(struct acpi_device *adev, int *ret_temp)
 {
-       return thermal_acpi_trip_temp(adev, "_HOT", ret_temp);
+       int temp_decik;
+       int ret = acpi_hot_trip_temp(adev, &temp_decik);
+
+       return thermal_temp(ret, temp_decik, ret_temp);
 }
 EXPORT_SYMBOL_GPL(thermal_acpi_hot_trip_temp);
 
@@ -111,6 +153,9 @@ EXPORT_SYMBOL_GPL(thermal_acpi_hot_trip_temp);
  */
 int thermal_acpi_critical_trip_temp(struct acpi_device *adev, int *ret_temp)
 {
-       return thermal_acpi_trip_temp(adev, "_CRT", ret_temp);
+       int temp_decik;
+       int ret = acpi_critical_trip_temp(adev, &temp_decik);
+
+       return thermal_temp(ret, temp_decik, ret_temp);
 }
 EXPORT_SYMBOL_GPL(thermal_acpi_critical_trip_temp);