ACPI: thinkpad-acpi: use a separate platform device for hwmon and name it (v2)

Use a separate platform device and driver ("thinkpad_hwmon") to attach
hwmon attributes and class, and add a name attribute of "thinkpad" to
it, which defines the hwmon device name for libsensors4.

This makes thinkpad-acpi compatible with libsensors4 from lm-sensors, and
the platform driver and device split will make it much easier to separate
hwmon functionality into its own module later on.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 19 insertions, 6 deletions

diff --git a/Documentation/thinkpad-acpi.txt b/Documentation/thinkpad-acpi.txt
index 60953d6c919d..3b95bbacc775 100644
--- a/Documentation/thinkpad-acpi.txt
+++ b/Documentation/thinkpad-acpi.txt
@@ -105,10 +105,15 @@ The version of thinkpad-acpi's sysfs interface is exported by the driver
 as a driver attribute (see below).
 
 Sysfs driver attributes are on the driver's sysfs attribute space,
-for 2.6.20 this is /sys/bus/platform/drivers/thinkpad_acpi/.
+for 2.6.23 this is /sys/bus/platform/drivers/thinkpad_acpi/ and
+/sys/bus/platform/drivers/thinkpad_hwmon/
 
-Sysfs device attributes are on the driver's sysfs attribute space,
-for 2.6.20 this is /sys/devices/platform/thinkpad_acpi/.
+Sysfs device attributes are on the thinkpad_acpi device sysfs attribute
+space, for 2.6.23 this is /sys/devices/platform/thinkpad_acpi/.
+
+Sysfs device attributes for the sensors and fan are on the
+thinkpad_hwmon device's sysfs attribute space, but you should locate it
+looking for a hwmon device with the name attribute of "thinkpad".
 
 Driver version
 --------------
@@ -766,7 +771,7 @@ Temperature sensors
 -------------------
 
 procfs: /proc/acpi/ibm/thermal
-sysfs device attributes: (hwmon) temp*_input
+sysfs device attributes: (hwmon "thinkpad") temp*_input
 
 Most ThinkPads include six or more separate temperature sensors but only
 expose the CPU temperature through the standard ACPI methods.  This
@@ -989,7 +994,9 @@ Fan control and monitoring: fan speed, fan enable/disable
 ---------------------------------------------------------
 
 procfs: /proc/acpi/ibm/fan
-sysfs device attributes: (hwmon) fan_input, pwm1, pwm1_enable
+sysfs device attributes: (hwmon "thinkpad") fan1_input, pwm1,
+                          pwm1_enable
+sysfs hwmon driver attributes: fan_watchdog
 
 NOTE NOTE NOTE: fan control operations are disabled by default for
 safety reasons.  To enable them, the module parameter "fan_control=1"
@@ -1131,7 +1138,7 @@ hwmon device attribute fan1_input:
         which can take up to two minutes.  May return rubbish on older
         ThinkPads.
 
-driver attribute fan_watchdog:
+hwmon driver attribute fan_watchdog:
         Fan safety watchdog timer interval, in seconds.  Minimum is
         1 second, maximum is 120 seconds.  0 disables the watchdog.
 
@@ -1233,3 +1240,9 @@ Sysfs interface changelog:
                 layer, the radio switch generates input event EV_RADIO,
                 and the driver enables hot key handling by default in
                 the firmware.
+
+0x020000:       ABI fix: added a separate hwmon platform device and
+                driver, which must be located by name (thinkpad)
+                and the hwmon class for libsensors4 (lm-sensors 3)
+                compatibility.  Moved all hwmon attributes to this
+                new platform device.