Jonathan writes: Second set of new device support, features and cleanup for the 4.3 cycle. Take 2 also includes a fix set that was too late for the 4.2 cycle. As we had a lot of tools and docs work in this set, I have broken those out into their own categories in this description. Fixes from the pull request '4th set of IIO fixes for the 4.2 cycle'. * Poll functions for both event chardev and the buffer one were returning negative error codes (via a positive value). * A recent change to lsiio adding some error handling that was wrong and stopped the tool working. * bmg160 was missing some dependencies in Kconfig * berlin2-adc had a misshandled register (wrote a value rather than a bitmap) New device support * TI opt3001 light sensor * TXC PA12 ALS and proximity sensor. * mcp3301 ADC support (in mcp320x driver) * ST lsm303agr accelerometer and magnetometer drivers (plus some st-sensors common support to allow different WHOAMI register addresses, devices with fixed scale and allow interrupt equiped magnetometers). * ADIS16305, ADIS16367, ADIS16445IMUs (in the adis16400 driver) * ADIS16266 gyro (in the adis16260 driver) * ADIS16137 gyro (in the adis16136 driver) New functionality * mmc35240 DT bindings. * Inverse unit conversion macros to aid handing of values written to sysfs attributes. Core cleanup * Forward declaration of struct iio_trigger to avoid a compile warning. Driver cleanup / fixes * mxs-lradc - Clarify which parts are supported. - Fix spelling erorrs. - Missing/extra includes - reorder includes - add datasheet name listings for all usable channels (to allow them to be bound by name from consumer drivers) * acpi-als - add some function prefixes as per general iio style. * bmc150_magn - replace a magic value with the existing define. * vf610 - determine possible sample frequencies taking into account the electrical characteristics (defining a minimum sample time) * dht11 - whitespace - additional docs - avoid mulitple assignments in one line - Use the new funciton ktime_get_resolution_ns to cleanup a nasty trick previously used for timing. * Fix all drivers that consider 0 a valid IRQ for historical reasons. * Export I2C module alias info where previously missing (to allow autoprobing) * Export OF module alias info where previously missing. * mmc35240 - switch some variables into arrays to improve readability. * mlx90614 - define some magic numbers for readability. * bmc150_magn - expand area locked by a mutex to cover all the use of the data->buffer. - use descriptive naming for a mask instead of a magic value. * berin2-adc - pass up an error code rather that a generic error - constify the iio_chan_spec - some other little tidy ups. * stk8312 - fix a dependency on triggered buffers in kconfig - add a check for invalid attribute values - improve error handling by returning error codes where possible and return immediately where relevant - rework macro defs to use GENMASK etc - change some variable types to reduce unnecessary casting - clean up code style - drop a local buffer copy for bulk reads and use the one in data->buffer instead. * adis16400 - the adis16448 gyroscope scale was wrong. * adis16480 - some more wrong scales for various parts. * adis16300 - has an undocumented product id and serial number registers so use them. * iio_simple_dummy - fix some wrong code indentation. * bmc150-accel - use the chip ID to detect the chip present rather than verifying the expected part was there. This was in response to a wrong ACPI entry on the WinBook TW100. * mma8452 - fix _get_hp_filter_index - drop a double include - pass up an error code rather than rewriting it - range check input values to attribute writes - register defs tidy up using GENMASK and reordering them to be easier to follow. - various coding style cleanups - put the Kconfig entry in the write place (alphabetically). Tools related * Tools cleanup - drop an explicity NULL comparison, some unnecessary braces, use the ARRAY_SIZE macro, send error messages to stderr instead of dropping them in the middle of normal output. * Fix tools to allow that scale and offset attributes are optional. * More tools fixes including allowing true 32bit data (previously an overflow prevented more than 31bits) * Drop a stray header guard that ended up in a c file. * Make calc_digits static as it isn't exported or in the header. * Set ci_array pointer to NULL after free as a protection against non safe usage of the tools core code. Also convert a double pointer to a single one as the extra level of indirection was unnecessary. Docs * DocBook introduction by Daniel Baluta. Glad we are beginning to draw together some more introductory docs to suplement the various tools / examples. * Drop bytes_per_datum sysfs attribute docs as it no longer exists. * A whole load of missing / fixing of kernel-doc for the core of IIO. * Document the trigger name sysfs attribute in the ABI docs. * Minor typos in the ABI docs related to power down modes.