atmel_serial: keep clock off when it's not needed

[linux-2.6-omap-h63xx.git] / Documentation / hwmon / f71805f

diff --git a/Documentation/hwmon/f71805f b/Documentation/hwmon/f71805f
index bfd0f154959cce0e3398e899e7b5a0619f2abcce..f0d55976740adfeabfb7258d4109a7d4c930c6ac 100644 (file)
--- a/Documentation/hwmon/f71805f
+++ b/Documentation/hwmon/f71805f
@@ -5,11 +5,15 @@ Supported chips:
   * Fintek F71805F/FG
     Prefix: 'f71805f'
     Addresses scanned: none, address read from Super I/O config space
   * Fintek F71805F/FG
     Prefix: 'f71805f'
     Addresses scanned: none, address read from Super I/O config space

-    Datasheet: Provided by Fintek on request
+    Datasheet: Available from the Fintek website
+  * Fintek F71806F/FG
+    Prefix: 'f71872f'
+    Addresses scanned: none, address read from Super I/O config space
+    Datasheet: Available from the Fintek website

   * Fintek F71872F/FG
     Prefix: 'f71872f'
     Addresses scanned: none, address read from Super I/O config space
   * Fintek F71872F/FG
     Prefix: 'f71872f'
     Addresses scanned: none, address read from Super I/O config space

-    Datasheet: Provided by Fintek on request
+    Datasheet: Available from the Fintek website

 
 Author: Jean Delvare <khali@linux-fr.org>
 
 
 Author: Jean Delvare <khali@linux-fr.org>
 


@@ -38,6 +42,9 @@ The Fintek F71872F/FG Super I/O chip is almost the same, with two
 additional internal voltages monitored (VSB and battery). It also features
 6 VID inputs. The VID inputs are not yet supported by this driver.
 
 additional internal voltages monitored (VSB and battery). It also features
 6 VID inputs. The VID inputs are not yet supported by this driver.
 

+The Fintek F71806F/FG Super-I/O chip is essentially the same as the
+F71872F/FG, and is undistinguishable therefrom.
+

 The driver assumes that no more than one chip is present, which seems
 reasonable.
 
 The driver assumes that no more than one chip is present, which seems
 reasonable.
 


@@ -128,7 +135,9 @@ it.
 When the PWM method is used, you can select the operating frequency,
 from 187.5 kHz (default) to 31 Hz. The best frequency depends on the
 fan model. As a rule of thumb, lower frequencies seem to give better
 When the PWM method is used, you can select the operating frequency,
 from 187.5 kHz (default) to 31 Hz. The best frequency depends on the
 fan model. As a rule of thumb, lower frequencies seem to give better

-control, but may generate annoying high-pitch noise. Fintek recommends
+control, but may generate annoying high-pitch noise. So a frequency just
+above the audible range, such as 25 kHz, may be a good choice; if this
+doesn't give you good linear control, try reducing it. Fintek recommends

 not going below 1 kHz, as the fan tachometers get confused by lower
 frequencies as well.
 
 not going below 1 kHz, as the fan tachometers get confused by lower
 frequencies as well.
 


@@ -136,16 +145,23 @@ When the DC method is used, Fintek recommends not going below 5 V, which
 corresponds to a pwm value of 106 for the driver. The driver doesn't
 enforce this limit though.
 
 corresponds to a pwm value of 106 for the driver. The driver doesn't
 enforce this limit though.
 

-Three different fan control modes are supported:
+Three different fan control modes are supported; the mode number is written
+to the pwm<n>_enable file.
+
+* 1: Manual mode
+  You ask for a specific PWM duty cycle or DC voltage by writing to the
+  pwm<n> file.

 
 

-* Manual mode
-  You ask for a specific PWM duty cycle or DC voltage.
+* 2: Temperature mode
+  You define 3 temperature/fan speed trip points using the
+  pwm<n>_auto_point<m>_temp and _fan files. These define a staircase
+  relationship between temperature and fan speed with two additional points
+  interpolated between the values that you define. When the temperature
+  is below auto_point1_temp the fan is switched off.

 
 

-* Fan speed mode
-  You ask for a specific fan speed. This mode assumes that pwm1
-  corresponds to fan1, pwm2 to fan2 and pwm3 to fan3.
+* 3: Fan speed mode
+  You ask for a specific fan speed by writing to the fan<n>_target file.

 
 

-* Temperature mode
-  You define 3 temperature/fan speed trip points, and the fan speed is
-  adjusted depending on the measured temperature, using interpolation.
-  This mode is not yet supported by the driver.
+Both of the automatic modes require that pwm1 corresponds to fan1, pwm2 to
+fan2 and pwm3 to fan3. Temperature mode also requires that temp1 corresponds
+to pwm1 and fan1, etc.