Pull IIO and staging fixes from Greg KH:
 "Here are a number of IIO and staging bugfixes for 4.7-rc4.

  Nothing huge, the normal amount of iio driver fixes, and some small
  staging driver bugfixes for some reported problems (2 are reverts of
  patches that went into 4.7-rc1).  All have been in linux-next with no
  reported issues"

* tag 'staging-4.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (24 commits)
  Revert "Staging: rtl8188eu: rtw_efuse: Use sizeof type *pointer instead of sizeof type."
  Revert "Staging: drivers: rtl8188eu: use sizeof(*ptr) instead of sizeof(struct)"
  staging: lustre: lnet: Don't access NULL NI on failure path
  iio: hudmidity: hdc100x: fix incorrect shifting and scaling
  iio: light apds9960: Add the missing dev.parent
  iio: Fix error handling in iio_trigger_attach_poll_func
  iio: st_sensors: Disable DRDY at init time
  iio: st_sensors: Init trigger before irq request
  iio: st_sensors: switch to a threaded interrupt
  iio: light: bh1780: assign a static name
  iio: bh1780: dereference the client properly
  iio: humidity: hdc100x: fix IIO_TEMP channel reporting
  iio:st_pressure: fix sampling gains (bring inline with ABI)
  iio: proximity: as3935: fix buffer stack trashing
  iio: proximity: as3935: remove triggered buffer processing
  iio: proximity: as3935: correct IIO_CHAN_INFO_RAW output
  max44000: Remove scale from proximity
  iio: humidity: am2315: Remove a stray unlock
  iio: humidity: hdc100x: correct humidity integration time mask
  iio: pressure: bmp280: fix error message for wrong chip id
  ...

With the introduction of the ISA_BUS_API Kconfig option, ISA-style
drivers may be built for X86_64 architectures. This patch changes the
ISA Kconfig option dependency of the Apex Embedded Systems STX104 DAC
driver to ISA_BUS_API, thus allowing it to build for X86_64 as it is
expected to.

Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Jonathan writes:

First round of iio fixes for the 4.7 cycle.

A slightly bumper set due to travel delaying the pull request and a fair few
issues with the recent merge window patches.  Patches all over the place.
The st-sensors one is probably the most involved, but definitly solves the
issues seen.  Note there are some other issues around that handler
(and the fact that a lot of boards tie a level interrupt chip to an
edge interrupt only irq chip).  These are not regressions however, so
will turn up the slow route.

* core
  - iio_trigger_attach_pollfunc had some really badly wrong error handling.
  Another nasty triggered whilst chasing down issues with the st sensors
  rework below.
* ad5592r
  - fix an off by one error when allocating channels.
* am2315
  - a stray mutex unlock before we ever take the lock.
* apds9960
  - missing a parent in the driver model (which should be the i2c device).
  Result is it doesn't turn up under /sys/bus/i2c/devices which some
  userspace code uses for repeatable device identification.
* as3935
  - ABI usage bug which meant a processed value was reported as raw. Now
    reporting scale as well to ensure userspace has the info it needs.
  - Don't return processed value via the buffer - it doesn't conform to
    the ABI and will overflow in some cases.
  - Fix a wrongly sized buffer which would overflow trashing part of the
    stack.  Also move it onto the heap as part of the fix.
* bh1780
  - a missing return after write in debugfs lead to an incorrect read and
    a null pointer dereference.
  - dereferencing the wrong pointer in suspend and resume leading to
    unpredictable results.
  - assign a static name to avoid accidentally ending up with no name if
    loaded via device tree.
* bmi160
  - output data rate for the accelerometer was incorrectly reported. Fix it.
  - writing the output data rate was also wrong due to reverse parameters.
* bmp280
  - error message for wrong chip ID gave the wrong expected value.
* hdc100x
  - mask for writing the integration time was wrong allowin g us to get
  'stuck' in a particular value with no way back.
  - temperature reported in celsius rather than millicelsius as per the
  ABI.
  - Get rid of some incorrect data shifting which lead to readings being
  rather incorrect.
* max44000
  - drop scale attribute for proximity as it is an unscaled value (depends
    on what is in range rather than anything knowable at the detector).
* st-pressure
  - ABI compliance fixes - units were wrong.
* st-sensors
  - We introduced some nasty issues with the recent switch over to a
  a somewhat threaded handler in that we broke using a software trigger
  with these devices.  Now do it properly.  It's a larger patch than ideal
  for a fix, but the logic is straight forward.
  - Make sure the trigger is initialized before requesting the interrupt.
  This matters now the interrupt can be shared. Before it was ugly and wrong
  but short of flakey hardware could not be triggered.
  - Hammer down the dataready pin at boot - otherwise with really
  unlucky timing things could get interestingly wedged requiring a hard power
  down of the chip.

Shifting sensor data to the right 2 bits was incorrect and caused the
scaling values + offsets to be invalid.

Reported-by: Alison Schofield <amsfield22@gmail.com>
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Tested-by: Alison Schofield <amsfield22@gmail.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Without this, the iio:deviceX is missing in the /sys/bus/i2c/devices/0-0039
Some userspace tools use this path to identify a specific instance of the
device.

Signed-off-by: Yong Li <sdliyong@gmail.com>
Reviewed-By: Matt Ranostay <mranostay@gmail.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

When attaching a pollfunc iio_trigger_attach_poll_func will allocate a
virtual irq and call the driver's set_trigger_state function. Fix error
handling to undo previous steps if any fails.

In particular this fixes handling errors from a driver's
set_trigger_state function. When using triggered buffers a failure to
enable the trigger used to make the buffer unusable.

Signed-off-by: Crestez Dan Leonard <leonard.crestez@intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

This fixes odd behavior after reboot.

The fact that we set the device to powerdown mode is not sufficient to
prevent DRDY being active because we might still have an unread sample.

Even if powerdown was sufficient keeping DRDY disabled while trigger is
not active is a good idea.

Cc: Giuseppe Barba <giuseppe.barba@st.com>
Cc: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Crestez Dan Leonard <leonard.crestez@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

This fixes a possible race where an interrupt arrives before complete
initialization and crashes because iio_trigger_get_drvdata returns NULL.

Cc: Giuseppe Barba <giuseppe.barba@st.com>
Cc: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Crestez Dan Leonard <leonard.crestez@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

commit 98ad8b41f58dff6b30713d7f09ae3834b8df7ded
("iio: st_sensors: verify interrupt event to status") caused
a regression when reading ST sensors from a HRTimer trigger
rather than the intrinsic interrupts: the HRTimer may
trigger faster than the sensor provides new values, and
as the check against new values available as a cause of
the interrupt trigger was done in the poll function,
this would bail out of the HRTimer interrupt with
IRQ_NONE.

So clearly we need to only check the new values available
from the proper interrupt handler and not from the poll
function, which should rather just read the raw values
from the registers, put them into the buffer and be happy.

To achieve this: switch the ST Sensors over to using a true
threaded interrupt handler.

In the interrupt thread, check if new values are available,
else yield to the (potential) next device on the same
interrupt line to check the registers. If the interrupt
was ours, proceed to poll the values.

Instead of relying on iio_trigger_generic_data_rdy_poll() as
a top half to wake up the thread that polls the sensor for
new data, have the thread call iio_trigger_poll_chained()
after determining that is is the proper source of the
interrupt. This is modelled on drivers/iio/accel/mma8452.c
which is already using a properly threaded interrupt handler.

In order to get the same precision in timestamps as
previously, where samples would be timestamped in the
poll function pf->timestamp when calling
iio_trigger_generic_data_rdy_poll() we introduce a
local timestamp in the sensor data, set it in the top half
(fastpath) of the interrupt handler and provide that to the
core when calling iio_push_to_buffers_with_timestamp().

Additionally: if the active scanmask is not set for the
sensor no IRQs should be enabled and we need to bail out
with IRQ_NONE. This can happen if spurious IRQs fire when
installing the threaded interrupt handler.

Tested with hard interrupt triggers on LIS331DL, then also
tested with hrtimers on the same sensor by creating a 75Hz
HRTimer and using it to poll the sensor.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Giuseppe Barba <giuseppe.barba@st.com>
Cc: Denis Ciocca <denis.ciocca@st.com>
Reported-by: Crestez Dan Leonard <cdleonard@gmail.com>
Tested-by: Crestez Dan Leonard <cdleonard@gmail.com>
Tested-by: Jonathan Cameron <jic23@kernel.org>
Fixes: 97865fe41322 ("iio: st_sensors: verify interrupt event to status")
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Using the struct i2c_device->id field for naming the light sensor
is a bad idea: when booting from the pure device tree this is NULL
and that causes the device not to have the "name" property in
sysfs and that in turn confuses the "lsiio" command to stop listing
devices.

So instead of using the device .id, use the hard string "bh1780",
which works just fine.

Fixes: 1f0477f18306 ("iio: light: new driver for the ROHM BH1780")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>