Most ST MEMS Sensors that support interrupts can also handle sending
an active low interrupt, i.e. going from high to low on data ready
(or other interrupt) and thus triggering on a falling edge to the
interrupt controller.

Set up logic to inspect the interrupt line we get for a sensor: if
it is triggering on rising edge, leave everything alone, but if it
triggers on falling edges, set up active low, and if unsupported
configurations appear: warn with errors and reconfigure the interrupt
to a rising edge, which all interrupt generating sensors support.

Create a local header for st_sensors_core.h to share functions
between the sensor core and the trigger setup code.

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

Fix the checkpatch warning of alignment should match open
parenthesis.
Signed-off-by: Shraddha Barke <shraddha.6596@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Replace bit shifting on 1 with the BIT(x) macro
Signed-off-by: Shraddha Barke <shraddha.6596@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Allow the current for both RED and IR LEDs to be set via an device tree
property setting.

This is an optional setting that is useful for applications that have a
known glass attenuation factor.
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

MCP4726 is a single channel 12-bit DAC.  We can support MCP4726 with
a little changes to mcp4725 driver.  In power-down mode, they have
different selection of VOUT pull-down registers.

MCP4726 also has features:
 - Output gain options: 1x, 2x
 - Voltage reference selection: VDD, VREF (Unbuffered or Buffered)

But these are not supported in this change. (1x gain, VDD is selected)

datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/22272C.pdfSigned-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Peter Meerwald <pmeerw@pmeerw.net>
Cc: linux-iio@vger.kernel.org
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

The MCP3425 is a single channel up to 16-bit A/D converter which has
features:

- On-Board Programmable Gain Amplifier (PGA):
 - Gains of 1, 2, 4 or 8
- Programmable Data Rate Options:
 - 15 SPS (16 bits), 60 SPS (14 bits), 240 SPS (12 bits)

The mcp3422 driver also supports the MCP3421 which is a single channel.
So we can support MCP3425 with a little changes to mcp3422 driver.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Angelo Compagnucci <angelo.compagnucci@gmail.com>
Cc: Peter Meerwald <pmeerw@pmeerw.net>
Cc: linux-iio@vger.kernel.org
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Merge tag 'iio-for-4.5c' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Third set of new stuff for IIO in the 4.5 cycle.

New driver features
- us5182
  * Add interrupt support and rising / falling threshold events.

Cleanups / fixes to new stuff / minor additions
* Expose the IIO value formatting function for drivers to
  make use of internally.
- ina2xx
   * Fix wrong channel order
   * Fix incorrect reporting of endianness
   * Adding documentation of ABI unique to this device
- mma8452
  * Drop an unused register description
  * Use an enum for the channel index to aid readability
- sca3000
  * Use standard NULL comparison style
- us5182
  * fix an inconsistency in status of enable (a bug with no real effect until
    above patches are applied)
  * refactor the read_raw function to improve maintainability / readability.

Merge tag 'iio-for-4.5b' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Second set of IIO new drivers, functionality and cleanups for the 4.5 cycle.

The big one here is the configfs support which has been a long time in the
works but should allow for cleaner ways to do instantiation of those elements
of IIO that aren't directly connected to specific hardware. Lots of cool new
stuff we can use this for in the works!

New core stuff (basically all configfs support related)
* Configfs support
  - Core support (was waiting for a configfs patch that went in around 4.4rc2)
  - A little fixlet to add a configfs.h to contain a reference to the
    configfs_subsystem structure.
* Some infrastructure to simplify handling of software based triggers
  (i.e. ones with no actual hardware associated with them)
* A high resolution timer based trigger.  This has been around for years
    but until the configfs support was ready we didn't have a sensible way
    of instantiating instances of it (the method used for the sysfs_trigger
    has never been really satisfactory)

New Device Support
* AMS iAQ Volatile Organic Compounds sensor support.
* Freescale imx7d ADC driver
* Maxim MAX30100 oximeter driver (note that for these devices most of the
  smart stuff will be in userspace - effectively they are just light sensors
  with some interesting led synchronization as far as the kernel is concerned).
* Microchip mcp3421 support added to the mcp3422 driver.
* TI adc124s021 support added to the adc128s052 driver.
* TI ina219, inda226 power monitors. Note that there is an existing hwmon driver
  for these parts, the usecase is somewhat different so it is unclear at this
  point if the hwmon driver will eventually be replaced by a bridge from
  this driver.  In the meantime the Kconfig dependencies should prevent both
  from being built.

New driver functionality
* us8152d power management support.

Cleanups, fixups
* Use list_for_each_entry_safe instead of list_for_each_safe with the entry
  bit coded longhand.
* Select IRQ_WORK for IIO_DUMMY_EVGEN.  This is a fix that somehow got lost
  when the driver was moved so lets do it again.
* st-accel - drop an unused define.
* vz89x, lidar - optimize i2c transactions by using a single i2c tranfers
  instead of multiple calls where supported (fall back to smbus calls as
  before if not).
* Use dev_get_platdata() in staging drivers: tsl2x7x, adcs and frequency
  drivers instead of direct access to the structure element.

This was extracted from a reposting of the driver after it had been applied
to the IIO tree.  I have fast tracked it as the driver will be in 4.5 and
it would be nice to fix this trivial issue before it is.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

A bit of refactoring for better readability.
Moved and slightly reorganized all the activity necessary for reading als
and proximity into a different function. This way the switch in read raw
becomes clearer and more compact.
Signed-off-by: Adriana Reus <adriana.reus@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Add interrupt support for proximity.
Add two threshold events to signal rising and falling directions.
Signed-off-by: Adriana Reus <adriana.reus@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

When setting als only or proximity only modes make sure that we mark the
other component as disabled. This fix is in preparation of adding event
support because that will make it possible to switch between one-shot and
continuous modes and not tracking these correctly may cause faulty
behaviour (e.g wrongfully considering px enabled and not setting an
appropriate mode in the chip).
Signed-off-by: Adriana Reus <adriana.reus@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Make IIO value formating function globally available to allow IIO drivers
to output values as the core does.
Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Simplify the code with list_first_entry_or_null().
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARCH_SHMOBILE is coming to arm64, which creates new warnings in allmodconfig:

drivers/staging/emxx_udc/emxx_udc.c: In function '_nbu2ss_out_dma':
drivers/staging/emxx_udc/emxx_udc.c:843:45: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
  _nbu2ss_writel(&preg->EP_DCR[num].EP_TADR, (u32)pBuffer);

This is clearly a mistake from confusing a dma_addr_t with a pointer,
so the fix is to use the correct types in two places.

The third warning of this kind is a check for an unaligned pointer,
which should be done by casting the pointer to uintptr_t, not int.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch makes plx9080.h use kernel types.
Signed-off-by: Moritz König <moritz.koenig@fau.de>
Signed-off-by: Fabian Lang <fabian.lang@fau.de>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Acked-by: Moritz Fischer <moritz.fischer@ettus.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch adds spaces around binary operators in plx9080.h.
Signed-off-by: Moritz König <moritz.koenig@fau.de>
Signed-off-by: Fabian Lang <fabian.lang@fau.de>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch fixes the format of comments in plx9080.h.
Signed-off-by: Moritz König <moritz.koenig@fau.de>
Signed-off-by: Fabian Lang <fabian.lang@fau.de>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch is to comedilib.h file that fixes up following warnings
reported by checkpatch.pl :
I) Block comments use * on subsequent lines.

Apart from it I have remove header file path by base file name as
suggested by community.
Signed-off-by: Jitendra Kumar Khasdev <jkhasdev@gmail.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The driver writes a couple of literal values to the counter
control/status register, 0x8000 to reset the counter, and 0x4000 to load
the counter from preload register 0.  Add a bunch of macros to define
these values and other values for the register, based on the Sensoray
526 manual.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The driver uses `struct counter_mode_register_t` to describe the 16-bit
counter mode register as a sequence of bitfield members.  The struct
appears as the type of one of the members of `union cmReg`, the other
member of which is of type `unsigned short`, so the driver can
manipulate the register value as a whole, or as individual fields.
Although this is fairly convenient, it's not that conventional.  The
code also needs to define the bitfield members in ascending or
descending order of the physical bits, depending on whether bitfields
are little- or big-endian.

Rip all that out and replace it with a bunch of macros to set and mask
out bits of the register value, as that's the more conventional way to
do it.  A bonus is that we get rid of a load of CamelCase definitions in
the process.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

If the "write" file operation handler, `comedi_write()` is passed 0 for
the amount to write, some error conditions are currently skipped and the
function just returns 0.  Change it to check those error conditions and
return an error value if appropriate.  The trickiest case is the check
for when the previously set up asynchronous command has terminated with
an error.  In that case, `-EPIPE` is returned (as it is for a write of
non-zero length) and the subdevice gets marked as non-busy.

A zero-length write that returns 0 has no other effects, in particular,
it does not cause the subdevice to be marked as non-busy.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In order to perform a "write" file operation, an asynchronous COMEDI
command in the "write" direction needs to have been set up by the
current file object on the COMEDI "write" subdevice associated with the
file object.  If there is a "write" subdevice, but a command has not
been set up by the file object (or is has been set-up in the wrong
direction), `comedi_write()` currently returns one of two error values
`-EINVAL` or `-EACCES`.  `-EACCES` is returned if the command was set up
by a different subdevice, or somewhat randomly, if a COMEDI
"instruction" is currently being processed.  `-EINVAL` is returned in
other cases.  Simplify it by returning `-EINVAL` for all these cases.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The "write" file operation handler, `comedi_write()` returns an error
for pretty much any condition that prevents a "write" going ahead.  One
of the conditions that prevents a "write" going ahead is that no
asynchronous command has been set up, but that currently results in a
return value of 0 (unless COMEDI instructions are being processed or an
asynchronous command has been set up by a different file object).
Change it to return `-EINVAL` in this case.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

`comedi_write()` copies data from the user buffer to the acquisition
data buffer, which is cyclic, using a single call to `copy_from_user()`.
It currently avoids having to deal with wraparound of the cyclic buffer
by limiting the amount it copies (and the amount returned to the user).
Change it to deal with the wraparound using two calls to
`copy_from_user()` if necessary.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

At one point in `comedi_write()`, the variable `n` gets assigned to the
minimum of the parameter `nbytes` and the amount of writeable buffer
space.  The way that is done currently is unsafe in the unlikely case
that `nbytes` exceeds `UINT_MAX`, so fix it.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In `comedi_write()`, the `n` and `m` variables are of type `int`.
Change them to `unsigned int` as they are used to measure a positive
number of bytes.  The `count` variable is also of type `int` and holds
the returned number of bytes written.  Change it to type `ssize_t` to
match the function's return type.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

`comedi_write()` is the handler for the "write" file operation for
COMEDI devices.  It mostly runs without using the main mutex of the
COMEDI device, but uses the `attach_lock` rw_semaphore to protect
against the COMEDI device becoming "detached".  A file object can write
data for a COMEDI asynchonous command if it initiated the command.  The
COMEDI subdevice is marked as busy when the command is started.  At some
point, the "write" handler detects that the command has terminated and
so marks the subdevice as non-busy.

In order to mark the subdevice as non-busy, the "write" handler needs to
release the `attach_lock` rw_semaphore and `acquire the main `mutex`.
There is a vulnerable point between the two, so it checks that the
device is still attached after acquiring the mutex.  However, it does
not currently check that the conditions for becoming non-busy still
hold.  Add some more checks that the subdevice is still busy with a
command initiated by the same file object, and that the command is in
the correct direction (in case the subdevice supports both "read" and
"write").
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Rearrange the code in `comedi_write()` to reduce the amount of
indentation.  The code never reiterates the `while` loop once `count`
has become non-zero, so we can check that in the `while` condition to
save an indentation level.  (Note that `nbytes` has been checked to be
non-zero before entering the loop, so we can remove that check.)  Move
the code that makes the subdevice "become non-busy" outside the `while`
loop, using a new flag variable `become_nonbusy` to decide whether it
needs to be done.  This simplifies the wait queue handling so there is a
single place where the task is removed from the wait queue, and we can
remove the `on_wait_queue` flag variable.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Change the MODULE_DESCRIPTION to something more useful than the
generic "Comedi low-level driver".
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The Description is a bit long winded and the same information is in
the Devices. Shorten the Description and tidy up the Devices.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This function is called as part of the pci_driver (*probe) before
doing the (*auto_attach) of the comedi driver. For aesthetics, move
the function to a more logical place in the driver.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

For aesthetics, move these defines after the register defines and rename
them to have namespace associated with the driver.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

For aesthetics, move this enum after the register defines and rename
it to have namespace associated with the driver.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This member of the boardinfo is identical to the offset of the boardinfo
in the boardtypes array. It's also passed as the 'context' to the driver
(*auto_attach).

The 'cardtype' is only needed by the (*auto_attach) to determine which
PCI BAR to use and in pci_dio_reset() to handle the board specific code.

Remove the 'cardtype' member and use the 'context' value instead.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

For aesthetics, use a common define for the interrupt control and status
registers.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

For aesthetics, rename this define and fix the alignment.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

For aesthetics, replace these defines with a macro.

Refactor the switch in pci_dio_reset() to use common code.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

For aesthetics, replace these defines with some macros.

Refactor the switch in pci_dio_reset() to not require the fallthrough
comment.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

These boards use the same offsets for the interrupt control registers.
For aesthetics, remove the current defines and use common ones.

Fix the switch() in pci_dio_reset() to use common code.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>