thermal: update the documentation

Update the documentation for the thermal driver hwmon sys I/F.

Change the ACPI thermal zone type to be consistent with hwmon.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Len Brown <len.brown@intel.com>

2 files changed, 28 insertions, 7 deletions

diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt
index d9f28be75403..70d68ce8640a 100644
--- a/Documentation/thermal/sysfs-api.txt
+++ b/Documentation/thermal/sysfs-api.txt
@@ -108,10 +108,12 @@ and throttle appropriate devices.
 RO      read only value
 RW      read/write value
 
-All thermal sysfs attributes will be represented under /sys/class/thermal
+Thermal sysfs attributes will be represented under /sys/class/thermal.
+Hwmon sysfs I/F extension is also available under /sys/class/hwmon
+if hwmon is compiled in or built as a module.
 
 Thermal zone device sys I/F, created once it's registered:
-|thermal_zone[0-*]:
+/sys/class/thermal/thermal_zone[0-*]:
         |-----type:                     Type of the thermal zone
         |-----temp:                     Current temperature
         |-----mode:                     Working mode of the thermal zone
@@ -119,7 +121,7 @@ Thermal zone device sys I/F, created once it's registered:
         |-----trip_point_[0-*]_type:    Trip point type
 
 Thermal cooling device sys I/F, created once it's registered:
-|cooling_device[0-*]:
+/sys/class/thermal/cooling_device[0-*]:
         |-----type :                    Type of the cooling device(processor/fan/...)
         |-----max_state:                Maximum cooling state of the cooling device
         |-----cur_state:                Current cooling state of the cooling device
@@ -130,10 +132,19 @@ They represent the relationship between a thermal zone and its associated coolin
 They are created/removed for each
 thermal_zone_bind_cooling_device/thermal_zone_unbind_cooling_device successful execution.
 
-|thermal_zone[0-*]
+/sys/class/thermal/thermal_zone[0-*]
         |-----cdev[0-*]:                The [0-*]th cooling device in the current thermal zone
         |-----cdev[0-*]_trip_point:     Trip point that cdev[0-*] is associated with
 
+Besides the thermal zone device sysfs I/F and cooling device sysfs I/F,
+the generic thermal driver also creates a hwmon sysfs I/F for each _type_ of
+thermal zone device. E.g. the generic thermal driver registers one hwmon class device
+and build the associated hwmon sysfs I/F for all the registered ACPI thermal zones.
+/sys/class/hwmon/hwmon[0-*]:
+        |-----name:                     The type of the thermal zone devices.
+        |-----temp[1-*]_input:          The current temperature of thermal zone [1-*].
+        |-----temp[1-*]_critical:       The critical trip point of thermal zone [1-*].
+Please read Documentation/hwmon/sysfs-interface for additional information.
 
 ***************************
 * Thermal zone attributes *
@@ -141,7 +152,10 @@ thermal_zone_bind_cooling_device/thermal_zone_unbind_cooling_device successful e
 
 type                            Strings which represent the thermal zone type.
                                 This is given by thermal zone driver as part of registration.
-                                Eg: "ACPI thermal zone" indicates it's a ACPI thermal device
+                                Eg: "acpitz" indicates it's an ACPI thermal device.
+                                In order to keep it consistent with hwmon sys attribute,
+                                this should be a short, lowercase string,
+                                not containing spaces nor dashes.
                                 RO
                                 Required
 
@@ -218,7 +232,7 @@ the sys I/F structure will be built like this:
 /sys/class/thermal:
 
 |thermal_zone1:
-        |-----type:                     ACPI thermal zone
+        |-----type:                     acpitz
         |-----temp:                     37000
         |-----mode:                     kernel
         |-----trip_point_0_temp:        100000
@@ -243,3 +257,10 @@ the sys I/F structure will be built like this:
         |-----type:                     Fan
         |-----max_state:                2
         |-----cur_state:                0
+
+/sys/class/hwmon:
+
+|hwmon0:
+        |-----name:                     acpitz
+        |-----temp1_input:              37000
+        |-----temp1_crit:               100000
diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index ec707ed1a70f..5e9641c93fcd 100644
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -1136,7 +1136,7 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
 
         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
                         tz->trips.active[i].flags.valid; i++, trips++);
-        tz->thermal_zone = thermal_zone_device_register("ACPI thermal zone",
+        tz->thermal_zone = thermal_zone_device_register("acpitz",
                                         trips, tz, &acpi_thermal_zone_ops);
         if (IS_ERR(tz->thermal_zone))
                 return -ENODEV;