thermal: use integers rather than strings for thermal values

The thermal API currently uses strings to pass values to userspace. This
makes it difficult to use from within the kernel. Change the interface
to use integers and fix up the consumers.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/acpi/fan.c

@@ -68,31 +68,35 @@ static struct acpi_driver acpi_fan_driver = {
 };
 
 /* thermal cooling device callbacks */
-static int fan_get_max_state(struct thermal_cooling_device *cdev, char *buf)
+static int fan_get_max_state(struct thermal_cooling_device *cdev, unsigned long
+			     *state)
 {
 	/* ACPI fan device only support two states: ON/OFF */
-	return sprintf(buf, "1\n");
+	*state = 1;
+	return 0;
 }
 
-static int fan_get_cur_state(struct thermal_cooling_device *cdev, char *buf)
+static int fan_get_cur_state(struct thermal_cooling_device *cdev, unsigned long
+			     *state)
 {
 	struct acpi_device *device = cdev->devdata;
-	int state;
 	int result;
+	int acpi_state;
 
 	if (!device)
 		return -EINVAL;
 
-	result = acpi_bus_get_power(device->handle, &state);
+	result = acpi_bus_get_power(device->handle, &acpi_state);
 	if (result)
 		return result;
 
-	return sprintf(buf, "%s\n", state == ACPI_STATE_D3 ? "0" :
-			 (state == ACPI_STATE_D0 ? "1" : "unknown"));
+	*state = (acpi_state == ACPI_STATE_D3 ? 0 :
+		 (acpi_state == ACPI_STATE_D0 ? 1 : -1));
+	return 0;
 }
 
 static int
-fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
+fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
 {
 	struct acpi_device *device = cdev->devdata;
 	int result;

drivers/acpi/processor_thermal.c

@@ -373,7 +373,8 @@ static int acpi_processor_max_state(struct acpi_processor *pr)
 	return max_state;
 }
 static int
-processor_get_max_state(struct thermal_cooling_device *cdev, char *buf)
+processor_get_max_state(struct thermal_cooling_device *cdev,
+			unsigned long *state)
 {
 	struct acpi_device *device = cdev->devdata;
 	struct acpi_processor *pr = acpi_driver_data(device);
@@ -381,28 +382,29 @@ processor_get_max_state(struct thermal_cooling_device *cdev, char *buf)
 	if (!device || !pr)
 		return -EINVAL;
 
-	return sprintf(buf, "%d\n", acpi_processor_max_state(pr));
+	*state = acpi_processor_max_state(pr);
+	return 0;
 }
 
 static int
-processor_get_cur_state(struct thermal_cooling_device *cdev, char *buf)
+processor_get_cur_state(struct thermal_cooling_device *cdev,
+			unsigned long *cur_state)
 {
 	struct acpi_device *device = cdev->devdata;
 	struct acpi_processor *pr = acpi_driver_data(device);
-	int cur_state;
 
 	if (!device || !pr)
 		return -EINVAL;
 
-	cur_state = cpufreq_get_cur_state(pr->id);
+	*cur_state = cpufreq_get_cur_state(pr->id);
 	if (pr->flags.throttling)
-		cur_state += pr->throttling.state;
-
-	return sprintf(buf, "%d\n", cur_state);
+		*cur_state += pr->throttling.state;
+	return 0;
 }
 
 static int
-processor_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
+processor_set_cur_state(struct thermal_cooling_device *cdev,
+			unsigned long state)
 {
 	struct acpi_device *device = cdev->devdata;
 	struct acpi_processor *pr = acpi_driver_data(device);

drivers/acpi/thermal.c

@@ -954,7 +954,8 @@ static void acpi_thermal_check(void *data)
 /* sys I/F for generic thermal sysfs support */
 #define KELVIN_TO_MILLICELSIUS(t) (t * 100 - 273200)
 
-static int thermal_get_temp(struct thermal_zone_device *thermal, char *buf)
+static int thermal_get_temp(struct thermal_zone_device *thermal,
+			    unsigned long *temp)
 {
 	struct acpi_thermal *tz = thermal->devdata;
 	int result;
@@ -966,25 +967,28 @@ static int thermal_get_temp(struct thermal_zone_device *thermal, char *buf)
 	if (result)
 		return result;
 
-	return sprintf(buf, "%ld\n", KELVIN_TO_MILLICELSIUS(tz->temperature));
+	*temp = KELVIN_TO_MILLICELSIUS(tz->temperature);
+	return 0;
 }
 
 static const char enabled[] = "kernel";
 static const char disabled[] = "user";
 static int thermal_get_mode(struct thermal_zone_device *thermal,
-				char *buf)
+				enum thermal_device_mode *mode)
 {
 	struct acpi_thermal *tz = thermal->devdata;
 
 	if (!tz)
 		return -EINVAL;
 
-	return sprintf(buf, "%s\n", tz->tz_enabled ?
-			enabled : disabled);
+	*mode = tz->tz_enabled ? THERMAL_DEVICE_ENABLED :
+		THERMAL_DEVICE_DISABLED;
+
+	return 0;
 }
 
 static int thermal_set_mode(struct thermal_zone_device *thermal,
-				const char *buf)
+				enum thermal_device_mode mode)
 {
 	struct acpi_thermal *tz = thermal->devdata;
 	int enable;
@@ -995,9 +999,9 @@ static int thermal_set_mode(struct thermal_zone_device *thermal,
 	/*
 	 * enable/disable thermal management from ACPI thermal driver
 	 */
-	if (!strncmp(buf, enabled, sizeof enabled - 1))
+	if (mode == THERMAL_DEVICE_ENABLED)
 		enable = 1;
-	else if (!strncmp(buf, disabled, sizeof disabled - 1))
+	else if (mode == THERMAL_DEVICE_DISABLED)
 		enable = 0;
 	else
 		return -EINVAL;
@@ -1013,7 +1017,7 @@ static int thermal_set_mode(struct thermal_zone_device *thermal,
 }
 
 static int thermal_get_trip_type(struct thermal_zone_device *thermal,
-				 int trip, char *buf)
+				 int trip, enum thermal_trip_type *type)
 {
 	struct acpi_thermal *tz = thermal->devdata;
 	int i;
@@ -1022,27 +1026,35 @@ static int thermal_get_trip_type(struct thermal_zone_device *thermal,
 		return -EINVAL;
 
 	if (tz->trips.critical.flags.valid) {
-		if (!trip)
-			return sprintf(buf, "critical\n");
+		if (!trip) {
+			*type = THERMAL_TRIP_CRITICAL;
+			return 0;
+		}
 		trip--;
 	}
 
 	if (tz->trips.hot.flags.valid) {
-		if (!trip)
-			return sprintf(buf, "hot\n");
+		if (!trip) {
+			*type = THERMAL_TRIP_HOT;
+			return 0;
+		}
 		trip--;
 	}
 
 	if (tz->trips.passive.flags.valid) {
-		if (!trip)
-			return sprintf(buf, "passive\n");
+		if (!trip) {
+			*type = THERMAL_TRIP_PASSIVE;
+			return 0;
+		}
 		trip--;
 	}
 
 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
 		tz->trips.active[i].flags.valid; i++) {
-		if (!trip)
-			return sprintf(buf, "active%d\n", i);
+		if (!trip) {
+			*type = THERMAL_TRIP_ACTIVE;
+			return 0;
+		}
 		trip--;
 	}
 
@@ -1050,7 +1062,7 @@ static int thermal_get_trip_type(struct thermal_zone_device *thermal,
 }
 
 static int thermal_get_trip_temp(struct thermal_zone_device *thermal,
-				 int trip, char *buf)
+				 int trip, unsigned long *temp)
 {
 	struct acpi_thermal *tz = thermal->devdata;
 	int i;
@@ -1059,31 +1071,39 @@ static int thermal_get_trip_temp(struct thermal_zone_device *thermal,
 		return -EINVAL;
 
 	if (tz->trips.critical.flags.valid) {
-		if (!trip)
-			return sprintf(buf, "%ld\n", KELVIN_TO_MILLICELSIUS(
-				tz->trips.critical.temperature));
+		if (!trip) {
+			*temp = KELVIN_TO_MILLICELSIUS(
+				tz->trips.critical.temperature);
+			return 0;
+		}
 		trip--;
 	}
 
 	if (tz->trips.hot.flags.valid) {
-		if (!trip)
-			return sprintf(buf, "%ld\n", KELVIN_TO_MILLICELSIUS(
-					tz->trips.hot.temperature));
+		if (!trip) {
+			*temp = KELVIN_TO_MILLICELSIUS(
+				tz->trips.hot.temperature);
+			return 0;
+		}
 		trip--;
 	}
 
 	if (tz->trips.passive.flags.valid) {
-		if (!trip)
-			return sprintf(buf, "%ld\n", KELVIN_TO_MILLICELSIUS(
-					tz->trips.passive.temperature));
+		if (!trip) {
+			*temp = KELVIN_TO_MILLICELSIUS(
+				tz->trips.passive.temperature);
+			return 0;
+		}
 		trip--;
 	}
 
 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
 		tz->trips.active[i].flags.valid; i++) {
-		if (!trip)
-			return sprintf(buf, "%ld\n", KELVIN_TO_MILLICELSIUS(
-					tz->trips.active[i].temperature));
+		if (!trip) {
+			*temp = KELVIN_TO_MILLICELSIUS(
+				tz->trips.active[i].temperature);
+			return 0;
+		}
 		trip--;
 	}
 

drivers/acpi/video.c

@@ -358,32 +358,36 @@ static struct output_properties acpi_output_properties = {
 
 
 /* thermal cooling device callbacks */
-static int video_get_max_state(struct thermal_cooling_device *cdev, char *buf)
+static int video_get_max_state(struct thermal_cooling_device *cdev, unsigned
+			       long *state)
 {
 	struct acpi_device *device = cdev->devdata;
 	struct acpi_video_device *video = acpi_driver_data(device);
 
-	return sprintf(buf, "%d\n", video->brightness->count - 3);
+	*state = video->brightness->count - 3;
+	return 0;
 }
 
-static int video_get_cur_state(struct thermal_cooling_device *cdev, char *buf)
+static int video_get_cur_state(struct thermal_cooling_device *cdev, unsigned
+			       long *state)
 {
 	struct acpi_device *device = cdev->devdata;
 	struct acpi_video_device *video = acpi_driver_data(device);
 	unsigned long long level;
-	int state;
+	int offset;
 
 	acpi_video_device_lcd_get_level_current(video, &level);
-	for (state = 2; state < video->brightness->count; state++)
-		if (level == video->brightness->levels[state])
-			return sprintf(buf, "%d\n",
-				       video->brightness->count - state - 1);
+	for (offset = 2; offset < video->brightness->count; offset++)
+		if (level == video->brightness->levels[offset]) {
+			*state = video->brightness->count - offset - 1;
+			return 0;
+		}
 
 	return -EINVAL;
 }
 
 static int
-video_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
+video_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
 {
 	struct acpi_device *device = cdev->devdata;
 	struct acpi_video_device *video = acpi_driver_data(device);

drivers/platform/x86/intel_menlow.c

@@ -57,8 +57,8 @@ MODULE_LICENSE("GPL");
  * In that case max_cstate would be n-1
  * GTHS returning '0' would mean that no bandwidth control states are supported
  */
-static int memory_get_int_max_bandwidth(struct thermal_cooling_device *cdev,
-					unsigned long *max_state)
+static int memory_get_max_bandwidth(struct thermal_cooling_device *cdev,
+				    unsigned long *max_state)
 {
 	struct acpi_device *device = cdev->devdata;
 	acpi_handle handle = device->handle;
@@ -83,22 +83,12 @@ static int memory_get_int_max_bandwidth(struct thermal_cooling_device *cdev,
 	return 0;
 }
 
-static int memory_get_max_bandwidth(struct thermal_cooling_device *cdev,
-				    char *buf)
-{
-	unsigned long value;
-	if (memory_get_int_max_bandwidth(cdev, &value))
-		return -EINVAL;
-
-	return sprintf(buf, "%ld\n", value);
-}
-
 static int memory_get_cur_bandwidth(struct thermal_cooling_device *cdev,
-				    char *buf)
+				    unsigned long *value)
 {
 	struct acpi_device *device = cdev->devdata;
 	acpi_handle handle = device->handle;
-	unsigned long long value;
+	unsigned long long result;
 	struct acpi_object_list arg_list;
 	union acpi_object arg;
 	acpi_status status = AE_OK;
@@ -108,15 +98,16 @@ static int memory_get_cur_bandwidth(struct thermal_cooling_device *cdev,
 	arg.type = ACPI_TYPE_INTEGER;
 	arg.integer.value = MEMORY_ARG_CUR_BANDWIDTH;
 	status = acpi_evaluate_integer(handle, MEMORY_GET_BANDWIDTH,
-				       &arg_list, &value);
+				       &arg_list, &result);
 	if (ACPI_FAILURE(status))
 		return -EFAULT;
 
-	return sprintf(buf, "%llu\n", value);
+	*value = result;
+	return 0;
 }
 
 static int memory_set_cur_bandwidth(struct thermal_cooling_device *cdev,
-				    unsigned int state)
+				    unsigned long state)
 {
 	struct acpi_device *device = cdev->devdata;
 	acpi_handle handle = device->handle;
@@ -126,7 +117,7 @@ static int memory_set_cur_bandwidth(struct thermal_cooling_device *cdev,
 	unsigned long long temp;
 	unsigned long max_state;
 
-	if (memory_get_int_max_bandwidth(cdev, &max_state))
+	if (memory_get_max_bandwidth(cdev, &max_state))
 		return -EFAULT;
 
 	if (state > max_state)
@@ -142,7 +133,7 @@ static int memory_set_cur_bandwidth(struct thermal_cooling_device *cdev,
 				  &temp);
 
 	printk(KERN_INFO
-	       "Bandwidth value was %d: status is %d\n", state, status);
+	       "Bandwidth value was %ld: status is %d\n", state, status);
 	if (ACPI_FAILURE(status))
 		return -EFAULT;
 

drivers/thermal/thermal_sys.c

@@ -104,22 +104,36 @@ static ssize_t
 temp_show(struct device *dev, struct device_attribute *attr, char *buf)
 {
 	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	long temperature;
+	int ret;
 
 	if (!tz->ops->get_temp)
 		return -EPERM;
 
-	return tz->ops->get_temp(tz, buf);
+	ret = tz->ops->get_temp(tz, &temperature);
+
+	if (ret)
+		return ret;
+
+	return sprintf(buf, "%ld\n", temperature);
 }
 
 static ssize_t
 mode_show(struct device *dev, struct device_attribute *attr, char *buf)
 {
 	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	enum thermal_device_mode mode;
+	int result;
 
 	if (!tz->ops->get_mode)
 		return -EPERM;
 
-	return tz->ops->get_mode(tz, buf);
+	result = tz->ops->get_mode(tz, &mode);
+	if (result)
+		return result;
+
+	return sprintf(buf, "%s\n", mode == THERMAL_DEVICE_ENABLED ? "enabled"
+		       : "disabled");
 }
 
 static ssize_t
@@ -132,7 +146,13 @@ mode_store(struct device *dev, struct device_attribute *attr,
 	if (!tz->ops->set_mode)
 		return -EPERM;
 
-	result = tz->ops->set_mode(tz, buf);
+	if (!strncmp(buf, "enabled", sizeof("enabled")))
+		result = tz->ops->set_mode(tz, THERMAL_DEVICE_ENABLED);
+	else if (!strncmp(buf, "disabled", sizeof("disabled")))
+		result = tz->ops->set_mode(tz, THERMAL_DEVICE_DISABLED);
+	else
+		result = -EINVAL;
+
 	if (result)
 		return result;
 
@@ -144,7 +164,8 @@ trip_point_type_show(struct device *dev, struct device_attribute *attr,
 		     char *buf)
 {
 	struct thermal_zone_device *tz = to_thermal_zone(dev);
-	int trip;
+	enum thermal_trip_type type;
+	int trip, result;
 
 	if (!tz->ops->get_trip_type)
 		return -EPERM;
@@ -152,7 +173,22 @@ trip_point_type_show(struct device *dev, struct device_attribute *attr,
 	if (!sscanf(attr->attr.name, "trip_point_%d_type", &trip))
 		return -EINVAL;
 
-	return tz->ops->get_trip_type(tz, trip, buf);
+	result = tz->ops->get_trip_type(tz, trip, &type);
+	if (result)
+		return result;
+
+	switch (type) {
+	case THERMAL_TRIP_CRITICAL:
+		return sprintf(buf, "critical");
+	case THERMAL_TRIP_HOT:
+		return sprintf(buf, "hot");
+	case THERMAL_TRIP_PASSIVE:
+		return sprintf(buf, "passive");
+	case THERMAL_TRIP_ACTIVE:
+		return sprintf(buf, "active");
+	default:
+		return sprintf(buf, "unknown");
+	}
 }
 
 static ssize_t
@@ -160,7 +196,8 @@ trip_point_temp_show(struct device *dev, struct device_attribute *attr,
 		     char *buf)
 {
 	struct thermal_zone_device *tz = to_thermal_zone(dev);
-	int trip;
+	int trip, ret;
+	long temperature;
 
 	if (!tz->ops->get_trip_temp)
 		return -EPERM;
@@ -168,7 +205,12 @@ trip_point_temp_show(struct device *dev, struct device_attribute *attr,
 	if (!sscanf(attr->attr.name, "trip_point_%d_temp", &trip))
 		return -EINVAL;
 
-	return tz->ops->get_trip_temp(tz, trip, buf);
+	ret = tz->ops->get_trip_temp(tz, trip, &temperature);
+
+	if (ret)
+		return ret;
+
+	return sprintf(buf, "%ld\n", temperature);
 }
 
 static DEVICE_ATTR(type, 0444, type_show, NULL);
@@ -236,8 +278,13 @@ thermal_cooling_device_max_state_show(struct device *dev,
 				      struct device_attribute *attr, char *buf)
 {
 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
+	unsigned long state;
+	int ret;
 
-	return cdev->ops->get_max_state(cdev, buf);
+	ret = cdev->ops->get_max_state(cdev, &state);
+	if (ret)
+		return ret;
+	return sprintf(buf, "%ld\n", state);
 }
 
 static ssize_t
@@ -245,8 +292,13 @@ thermal_cooling_device_cur_state_show(struct device *dev,
 				      struct device_attribute *attr, char *buf)
 {
 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
+	unsigned long state;
+	int ret;
 
-	return cdev->ops->get_cur_state(cdev, buf);
+	ret = cdev->ops->get_cur_state(cdev, &state);
+	if (ret)
+		return ret;
+	return sprintf(buf, "%ld\n", state);
 }
 
 static ssize_t
@@ -255,10 +307,10 @@ thermal_cooling_device_cur_state_store(struct device *dev,
 				       const char *buf, size_t count)
 {
 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
-	int state;
+	unsigned long state;
 	int result;
 
-	if (!sscanf(buf, "%d\n", &state))
+	if (!sscanf(buf, "%ld\n", &state))
 		return -EINVAL;
 
 	if (state < 0)
@@ -312,13 +364,20 @@ static DEVICE_ATTR(name, 0444, name_show, NULL);
 static ssize_t
 temp_input_show(struct device *dev, struct device_attribute *attr, char *buf)
 {
+	long temperature;
+	int ret;
 	struct thermal_hwmon_attr *hwmon_attr
 			= container_of(attr, struct thermal_hwmon_attr, attr);
 	struct thermal_zone_device *tz
 			= container_of(hwmon_attr, struct thermal_zone_device,
 				       temp_input);
 
-	return tz->ops->get_temp(tz, buf);
+	ret = tz->ops->get_temp(tz, &temperature);
+
+	if (ret)
+		return ret;
+
+	return sprintf(buf, "%ld\n", temperature);
 }
 
 static ssize_t
@@ -330,8 +389,14 @@ temp_crit_show(struct device *dev, struct device_attribute *attr,
 	struct thermal_zone_device *tz
 			= container_of(hwmon_attr, struct thermal_zone_device,
 				       temp_crit);
+	long temperature;
+	int ret;
+
+	ret = tz->ops->get_trip_temp(tz, 0, &temperature);
+	if (ret)
+		return ret;
 
-	return tz->ops->get_trip_temp(tz, 0, buf);
+	return sprintf(buf, "%ld\n", temperature);
 }
 
 

include/linux/thermal.h

@@ -31,23 +31,39 @@
 struct thermal_zone_device;
 struct thermal_cooling_device;
 
+enum thermal_device_mode {
+	THERMAL_DEVICE_DISABLED = 0,
+	THERMAL_DEVICE_ENABLED,
+};
+
+enum thermal_trip_type {
+	THERMAL_TRIP_ACTIVE = 0,
+	THERMAL_TRIP_PASSIVE,
+	THERMAL_TRIP_HOT,
+	THERMAL_TRIP_CRITICAL,
+};
+
 struct thermal_zone_device_ops {
 	int (*bind) (struct thermal_zone_device *,
 		     struct thermal_cooling_device *);
 	int (*unbind) (struct thermal_zone_device *,
 		       struct thermal_cooling_device *);
-	int (*get_temp) (struct thermal_zone_device *, char *);
-	int (*get_mode) (struct thermal_zone_device *, char *);
-	int (*set_mode) (struct thermal_zone_device *, const char *);
-	int (*get_trip_type) (struct thermal_zone_device *, int, char *);
-	int (*get_trip_temp) (struct thermal_zone_device *, int, char *);
+	int (*get_temp) (struct thermal_zone_device *, unsigned long *);
+	int (*get_mode) (struct thermal_zone_device *,
+			 enum thermal_device_mode *);
+	int (*set_mode) (struct thermal_zone_device *,
+		enum thermal_device_mode);
+	int (*get_trip_type) (struct thermal_zone_device *, int,
+		enum thermal_trip_type *);
+	int (*get_trip_temp) (struct thermal_zone_device *, int,
+			      unsigned long *);
 	int (*get_crit_temp) (struct thermal_zone_device *, unsigned long *);
 };
 
 struct thermal_cooling_device_ops {
-	int (*get_max_state) (struct thermal_cooling_device *, char *);
-	int (*get_cur_state) (struct thermal_cooling_device *, char *);
-	int (*set_cur_state) (struct thermal_cooling_device *, unsigned int);
+	int (*get_max_state) (struct thermal_cooling_device *, unsigned long *);
+	int (*get_cur_state) (struct thermal_cooling_device *, unsigned long *);
+	int (*set_cur_state) (struct thermal_cooling_device *, unsigned long);
 };
 
 #define THERMAL_TRIPS_NONE -1