enum scan_conn_timer and its instances are never used anywhere
in the code so, remove it.
Semantic patch used:

@@
type T;
identifier i;
constant C;
position p != e.p;
@@

- T i@p;
  <+... when != i
- i = C;
  ...+>
Signed-off-by: Shivani Bhardwaj <shivanib134@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Merge tag 'iio-for-4.4b' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Second set of new drivers, functionality and cleanups for IIO in the 4.4 cycle.

Core stuff
* adjust resistance documentation to allow for output devices.

New device support:
* bmc150
 - split the i2c driver up into a core and i2c_regmap part including regmap
   conversion.
 - add spi support.
* mcp4531 digitial potentiometer driver.
* Measurement Specialties set of drivers with a core library module providing
  common functionality.  Note that the htu21 has a driver in hwmon, but the
  view from that side was that, given the range of devices the same silicon
  turns up in are not all typical hwmon material, that driver would be
  deprecated in favour of this new support.
 - ms8607 temperature, pressure and humidty sensor
 - ms5637 temperature and pressure sensor
 - htu21 temperature and humidity sensor
 - tsys02d temperature sensor
 - tsys01 temperature sensor

Cleanups
* tree wide.
 - squish cases where irq 0 is still considered valid.
* apds9960
 - sparse endian warning cleanups by making endianness explicit.
* ad5504
 - leave group naming to the core.
* ad7746
 - cleanup comment style.
 - drop an unnecessary bit of dev_info
 - add some appropriate uses of the BIT macro.
* ad799x
 - leave group naming to the core.
* hdc100x - introduced this cycle,.
 - fix a wrong offset value.
* lidar
 - add missing MODULE_DEVICE_TABLE for dt.
* max1363
 - leave sysfs group naming to the core.
* m62332 got the Harmut treatment and as ever he found a 'few' bits the
  rest of us had missed!
 - Share scale and offset attributes across channels.
 - Shutdown the device on driver remove
 - Use ARRAY_SIZE rather than a hard coded count for channels.
 - Return more directly in the write_raw callback dropping a local variable
   along the way.
 - a few style issues
 - move to reading the regulator voltage for each use allowing for dynamic
   regulators.  This is a common feature across drivers so we might end
   up with more fixes throughout the tree for this.
* mlx96014 - introduced this cycle.
 - fixed up a spot of error handling.
* vz89x - introduced this cycle.
 - work around a hardware quirk.

Problem found using checkpatch.pl
CHECK: Comparison to NULL could be written "key"
Signed-off-by: Aybuke Ozdemir <aybuke.147@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove a cast which is not required.
Signed-off-by: Shivani Bhardwaj <shivanib134@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove a NULL test on variable hif_drv as it is already preceded by one.
Signed-off-by: Shivani Bhardwaj <shivanib134@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Replace kmalloc and memset with a single call to kzalloc.
Signed-off-by: Shraddha Barke <shraddha.6596@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In a recent change, we made a bool into a tristate in:
"drivers/staging: make android tegra_ion.c properly tristate", since it
was self evident that was the original intention.  However on the final
link phase we'll see an allmodconfig fail with:

ERROR: "ion_device_add_heap" [drivers/staging/android/ion/tegra/tegra_ion.ko] undefined!
ERROR: "ion_heap_create" [drivers/staging/android/ion/tegra/tegra_ion.ko] undefined!
ERROR: "ion_device_create" [drivers/staging/android/ion/tegra/tegra_ion.ko] undefined!
ERROR: "ion_heap_destroy" [drivers/staging/android/ion/tegra/tegra_ion.ko] undefined!
ERROR: "ion_device_destroy" [drivers/staging/android/ion/tegra/tegra_ion.ko] undefined!

Export the above using the non GPL specific export, since that is what
the rest of the ion code base does.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Arve Hjønnevåg" <arve@android.com>
Cc: Riley Andrews <riandrews@android.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Markus Elfring <elfring@users.sourceforge.net>
Cc: devel@driverdev.osuosl.org
Cc: linux-tegra@vger.kernel.org
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In fbtft-bus.c:fbtft_write_vmem16_bus9(), ioread8() is used for
accessing the provided screen array. Since screen_buffer actually
points to an ordinary buffer, instead access it directly.
Signed-off-by: Lars Svensson <lars1.svensson@sonymobile.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Member screen_base in struct fb_info is declared with __iomem
qualifier causing sparse warnings when used as a regular ponter.
To avoid the warnings, instead use alternate non-__iomem pointer,
screen_buffer, troughout the driver.
Signed-off-by: Lars Svensson <lars1.svensson@sonymobile.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Some drivers use member screen_base of struct fb_info to store non-
__iomem pointers, creating the need for ugly __force typecasts to
avoid sparse warnings. This adds an alternate pointer without the
__iomem qualifyer for this use.
Signed-off-by: Lars Svensson <lars1.svensson@sonymobile.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch adds support for the C-Berry28, a small 2.8" color display
with a resolution of 320x240 pixels from admatec for the Raspberry Pi.
It uses the Sitronix ST7789V display controller along with a custom
init sequence and custom gamma curves.
Signed-off-by: Dennis Menschel <menschel-d@posteo.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch adds support for the Sitronix ST7789V display controller.
The controller is intended for small color displays with a resolution
of up to 320x240 pixels.
Signed-off-by: Dennis Menschel <menschel-d@posteo.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Use the BIT(x) macro directly instead using multiple
BITX defines.
Signed-off-by: Anish Bhatt <anish@gatech.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Fix the checkpatch.pl issues:

CHECK: spaces preferred around that '*' (ctx:VxV)
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>

Fix the checkpatch.pl issues:

CHECK: spinlock_t definition without comment
CHECK: struct mutes definition withoug comment
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 "read" file operation handler, `comedi_read()` is passed 0 for
the amount to read, 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 read of
non-zero length) and the subdevice gets marked as non-busy.

A zero-length read that returns 0 has no other effects, in particular,
it does not cause the subdevice to be marked as non-busy, and the return
value does not indicate an "end-of-file" condition.
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 "read" file operation, an asynchronous COMEDI
command in the "read" direction needs to have been set up by the current
file object on the COMEDI "read" subdevice associated with the file
object.  If there is a "read" subdevice, but a command has not been set
up by the file object (or is has been set-up in the wrong direction),
`comedi_read()` 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 "read" file operation handler, `comedi_read()` returns an error for
pretty much any condition that prevents a "read" going ahead.  One of
the conditions that prevents a "read" 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_read()` initializes `retval` to 0.  The other `retval = 0`
assignments are superfluous, so remove them.
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_read()` copies data from the acquisition data buffer, which is
cyclic, to the user buffer using a single call to `copy_to_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_to_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_read()`, the variable `n` gets assigned to the
minimum of the parameter `nbytes` and the amount of readable buffer
space `m`.  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_read()`, 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.  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_read()` is the handler for the "read" file operation for COMEDI
devices.  It mostly runs without using the main mutex of the COMEDI
device, but uses the `attach_lock` rwsemaphore to protect against the
COMEDI device becoming "detached".  A file object can read data
resulting from 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 "read" handler detects that the command has terminated
and all available data has been read and so marks the subdevice as
non-busy.

In order to mark the subdevice as non-busy, the "read" handler needs to
release the `attach_lock` rwsemaphore 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, that command is in the correct
direction (in case the subdevice supports both "read" and "write"), that
command has terminated, and has no data available to be read.
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 an asynchronous "read" command is no longer running but the subdevice
is still busy, it becomes non-busy once there is no more data available
in the buffer.  Some or all of the data written to the buffer might not
have been "munged" yet, and it cannot be read until it has been munged
by the writer.  However, since the command is no longer running, we
cannot expect any remaining unmunged data to get munged so we should
ignore it.  Call `comedi_buf_read_n_available()` to check the amount of
munged data available to be read, replacing the call to
`comedi_buf_n_bytes_ready()` which checked the amount of written (but
possibly not yet munged) data available to be read.  This affects both
the "read" file operation (done in `comedi_read()`) and the
`COMEDI_BUFINFO` ioctl handling (done in `do_bufinfo_ioctl()`).  (The
latter is used when data is transferred directly through the mmapped
buffer instead of via the "read" file operation.)
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 a COMEDI subdevice is busy handling an asynchronous command in the
"read" direction, then after the command has terminated itself, the
"read" file operation handler, `comedi_read()` should keep the subdevice
busy until all available data has been read and it has returned 0 to
indicate an "end-of-file" condition.  Currently, it has a bug where it
can mark the subdevice as non-busy even when returning a non-zero count.
The bug is slightly hidden because the next "read" will return 0 because
the subdevice is no longer busy.  Fix it by checking the return count is
0 before deciding to mark the subdevice as non-busy.

The call to `comedi_is_subdevice_idle()` is superfluous as the
`become_nonbusy` variable will have been set to `true` when considering
becoming non-busy.  Strictly speaking, checking the return count is
superfluous too, as `become_nonbusy` doesn't get set to `true` unless
the count is 0, but check the return count anyway to make the intention
clearer.
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 main mutex in a comedi device can get held for quite a while when
processing comedi instructions, so for performance reasons, the "read"
and "write" file operations do not use it; they use use the
`attach_lock` rwsemaphore to protect against the comedi device becoming
detached at an inopportune moment.  Do the same for the "poll" file
operation.
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>

Currently, the "poll" file operation checks if an asynchronous "read"
(or "write" command is active on the "read" (or "write" subdevice, but
does not consider whether the command was started from the file object
being polled.  Since that is the only file object able to read (or
write) data, take it into consideration.

With this change, if no read (or write) command is running on the
subdevice, or it is started by a different file object, the file object
is marked as readable (or writeable) regardless, but the read (or write)
file operation will return an error.
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>

When handling the "poll" file operation and checking for `POLLOUT`,
don't allocate space from the buffer for writing, just check that space
is available for writing.  That check is done after checking that an
asynchronous "write" command is running on the subdevice.  Allocating
the buffer space before checking a "write" command is running can cause
problems if the subdevice supports commands in either direction and
currently has an active "read" command.
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>

Add a new function `comedi_buf_write_n_available()` to return the amount
of buffer space available for writing, including space already allocated
by `comedi_buf_write_alloc()` plus any unallocated space available.
This is currently just for internal use by the comedi core, so is not
exported.
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>

Rename the local function `comedi_buf_write_n_available()` to
`comedi_buf_write_n_unalloc()`.  It is the amount of unallocated space
available in the buffer that is available to be allocated for writing
and does not include the space that has already been allocated for
writing.  This is unlike the exported function
`comedi_buf_read_n_available()` which includes the space available to be
allocated for reading plus the space already allocated for reading.  The
new name breaks the unintentional naming symmetry (and also clears the
way for the old name to be reused for a new function).
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 subdevices that support asynchronous acquisition commands have a
wait queue head used for blocking reads or writes and for the poll file
operation.  The comedi device may have several subdevices that support
"read" and/or "write" commands, but each open file object has at most
one "read" subdevice and one "write" subdevice.  It's possible (though
rare) for those to be the same subdevice if the subdevice supports
commands in either direction.  In that case, the "poll" file operation
doesn't really need to do a `poll_wait()` on the same subdevice twice.
Although harmless, it wastes a poll table entry.  Check for that, and
avoid 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>

For aesthetics, rename these private data members to match the registers
they are associated with.
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 comment to follow the format of the other
subdevices.
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 PC-CARD DAS16/16-AO board only has 4 digital I/O channels. The other
boards supported by this driver have 8. Add the boardinfo to correctly
initialize the subdevice.
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 hardware has an 8254 counter/timer to provide a pacer clock using
counters 1 and 2. Counter 0 is available to the user.

Hook up the subdevice support to allow the user to use counter 0.
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 driver currently code not support async commands. Remove the
SDF_CMD_READ subdev_flag and len_chanlist initialization from the
subdevice init.

For aesthetics, rename the (*insn_read) function.
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>

Only one of the boards supported by this driver has analog outputs.
For aesthetics, change the 'n_ao_chans' member of the boardinfo into
a bit-field flag 'has_ao'.
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>

Define the bits in these registers and use them to remove the "magic"
values 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>

The ai mux register is used program the hi/lo channels in a scan.
According to the user manual, the hi and lo channels should be
the same  to sample one channel.

Introduce some macros to set the appropriate bits in the ai mux
register and fix the ai (*insn_read).
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, add _REG to all the register map offsets and convert
the values to hex.
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>