diff --git a/Documentation/hwmon/it87 b/Documentation/hwmon/it87
index 8d08bf0..38425f0 100644
--- a/Documentation/hwmon/it87
+++ b/Documentation/hwmon/it87
@@ -22,6 +22,10 @@
     Prefix: 'it8720'
     Addresses scanned: from Super I/O config space (8 I/O ports)
     Datasheet: Not publicly available
+  * IT8721F/IT8758E
+    Prefix: 'it8721'
+    Addresses scanned: from Super I/O config space (8 I/O ports)
+    Datasheet: Not publicly available
   * SiS950   [clone of IT8705F]
     Prefix: 'it87'
     Addresses scanned: from Super I/O config space (8 I/O ports)
@@ -67,7 +71,7 @@
 -----------
 
 This driver implements support for the IT8705F, IT8712F, IT8716F,
-IT8718F, IT8720F, IT8726F and SiS950 chips.
+IT8718F, IT8720F, IT8721F, IT8726F, IT8758E and SiS950 chips.
 
 These chips are 'Super I/O chips', supporting floppy disks, infrared ports,
 joysticks and other miscellaneous stuff. For hardware monitoring, they
@@ -86,14 +90,15 @@
 upper VID bits share their pins with voltage inputs (in5 and in6) so you
 can't have both on a given board.
 
-The IT8716F, IT8718F, IT8720F and later IT8712F revisions have support for
-2 additional fans. The additional fans are supported by the driver.
+The IT8716F, IT8718F, IT8720F, IT8721F/IT8758E and later IT8712F revisions
+have support for 2 additional fans. The additional fans are supported by the
+driver.
 
-The IT8716F, IT8718F and IT8720F, and late IT8712F and IT8705F also have
-optional 16-bit tachometer counters for fans 1 to 3. This is better (no more
-fan clock divider mess) but not compatible with the older chips and
-revisions. The 16-bit tachometer mode is enabled by the driver when one
-of the above chips is detected.
+The IT8716F, IT8718F, IT8720F and IT8721F/IT8758E, and late IT8712F and
+IT8705F also have optional 16-bit tachometer counters for fans 1 to 3. This
+is better (no more fan clock divider mess) but not compatible with the older
+chips and revisions. The 16-bit tachometer mode is enabled by the driver when
+one of the above chips is detected.
 
 The IT8726F is just bit enhanced IT8716F with additional hardware
 for AMD power sequencing. Therefore the chip will appear as IT8716F
@@ -115,7 +120,12 @@
 maximum limit. Note that minimum in this case always means 'closest to
 zero'; this is important for negative voltage measurements. All voltage
 inputs can measure voltages between 0 and 4.08 volts, with a resolution of
-0.016 volt. The battery voltage in8 does not have limit registers.
+0.016 volt (except IT8721F/IT8758E: 0.012 volt.) The battery voltage in8 does
+not have limit registers.
+
+On the IT8721F/IT8758E, some voltage inputs are internal and scaled inside
+the chip (in7, in8 and optionally in3). The driver handles this transparently
+so user-space doesn't have to care.
 
 The VID lines (IT8712F/IT8716F/IT8718F/IT8720F) encode the core voltage value:
 the voltage level your processor should work with. This is hardcoded by