Merge tag 'char-misc-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big set of new char/misc driver drivers and features for
  4.12-rc1.

  There's lots of new drivers added this time around, new firmware
  drivers from Google, more auxdisplay drivers, extcon drivers, fpga
  drivers, and a bunch of other driver updates. Nothing major, except if
  you happen to have the hardware for these drivers, and then you will
  be happy :)

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (136 commits)
  firmware: google memconsole: Fix return value check in platform_memconsole_init()
  firmware: Google VPD: Fix return value check in vpd_platform_init()
  goldfish_pipe: fix build warning about using too much stack.
  goldfish_pipe: An implementation of more parallel pipe
  fpga fr br: update supported version numbers
  fpga: region: release FPGA region reference in error path
  fpga altera-hps2fpga: disable/unprepare clock on error in alt_fpga_bridge_probe()
  mei: drop the TODO from samples
  firmware: Google VPD sysfs driver
  firmware: Google VPD: import lib_vpd source files
  misc: lkdtm: Add volatile to intentional NULL pointer reference
  eeprom: idt_89hpesx: Add OF device ID table
  misc: ds1682: Add OF device ID table
  misc: tsl2550: Add OF device ID table
  w1: Remove unneeded use of assert() and remove w1_log.h
  w1: Use kernel common min() implementation
  uio_mf624: Align memory regions to page size and set correct offsets
  uio_mf624: Refactor memory info initialization
  uio: Allow handling of non page-aligned memory regions
  hangcheck-timer: Fix typo in comment
  ...

1 files changed, 63 insertions, 0 deletions

diff --git a/Documentation/w1/slaves/w1_ds2438 b/Documentation/w1/slaves/w1_ds2438
new file mode 100644
index 000000000000..b99f3674c5b4
--- /dev/null
+++ b/Documentation/w1/slaves/w1_ds2438
@@ -0,0 +1,63 @@
+Kernel driver w1_ds2438
+=======================
+
+Supported chips:
+  * Maxim DS2438 Smart Battery Monitor
+
+supported family codes:
+        W1_FAMILY_DS2438        0x26
+
+Author: Mariusz Bialonczyk <manio@skyboo.net>
+
+Description
+-----------
+
+The DS2438 chip provides several functions that are desirable to carry in
+a battery pack. It also has a 40 bytes of nonvolatile EEPROM.
+Because the ability of temperature, current and voltage measurement, the chip
+is also often used in weather stations and applications such as: rain gauge,
+wind speed/direction measuring, humidity sensing, etc.
+
+Current support is provided through the following sysfs files (all files
+except "iad" are readonly):
+
+"iad"
+-----
+This file controls the 'Current A/D Control Bit' (IAD) in the
+Status/Configuration Register.
+Writing a zero value will clear the IAD bit and disables the current
+measurements.
+Writing value "1" is setting the IAD bit (enables the measurements).
+The IAD bit is enabled by default in the DS2438.
+
+When writing to sysfs file bits 2-7 are ignored, so it's safe to write ASCII.
+An I/O error is returned when there is a problem setting the new value.
+
+"page0"
+-------
+This file provides full 8 bytes of the chip Page 0 (00h).
+This page contains the most frequently accessed information of the DS2438.
+Internally when this file is read, the additional CRC byte is also obtained
+from the slave device. If it is correct, the 8 bytes page data are passed
+to userspace, otherwise an I/O error is returned.
+
+"temperature"
+-------------
+Opening and reading this file initiates the CONVERT_T (temperature conversion)
+command of the chip, afterwards the temperature is read from the device
+registers and provided as an ASCII decimal value.
+
+Important: The returned value has to be divided by 256 to get a real
+temperature in degrees Celsius.
+
+"vad", "vdd"
+------------
+Opening and reading this file initiates the CONVERT_V (voltage conversion)
+command of the chip.
+
+Depending on a sysfs filename a different input for the A/D will be selected:
+vad: general purpose A/D input (VAD)
+vdd: battery input (VDD)
+
+After the voltage conversion the value is returned as decimal ASCII.
+Note: The value is in mV, so to get a volts the value has to be divided by 10.