Coding style: avoid multiple assignments
Signed-off-by: Loic Pefferkorn <loic@loicp.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Coding style: document mutex usage
Signed-off-by: Loic Pefferkorn <loic@loicp.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Coding style: fix alignment to match open parenthesis
Signed-off-by: Loic Pefferkorn <loic@loicp.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Coding style: document spinlock usage
Signed-off-by: Loic Pefferkorn <loic@loicp.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Coding style: remove useless space after a cast
Signed-off-by: Loic Pefferkorn <loic@loicp.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Coding style: suppress consecutive blank lines
Signed-off-by: Loic Pefferkorn <loic@loicp.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This fixes "void function return statements are not generally useful"
warnings from checkpatch.pl.
Signed-off-by: Michał Bartoszkiewicz <mbartoszkiewicz@gmail.com>
Reviewed-by: Insop Song <insop.song@gainspeed.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Filipe Gonçalves <filipe@codinghighway.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Break lines exceeding 80 characters
Signed-off-by: Piotr Witoslawski <pwitos@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

lmv_internal.h:96: ERROR: space prohibited after that open parenthesis '('
lmv_internal.h:96: ERROR: space required before the open parenthesis '('
lmv_internal.h:147: WARNING: space prohibited between function name and open parenthesis '('
Signed-off-by: Juston Li <juston.h.li@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Chaitra Ramaiah <linux.delve@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
Cc: Greg Kroah-Hartman <gregkh@linux.com>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Grzegorz Swirski <grzegorz@swirski.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

`struct pci230_private` has two members to manage the enabled interrupt
sources.  `int_en` is the interrupt sources we want to be enabled and
`ier` is a shadow of the write-only interrupt enable register.  They
have the same value most of the time.  They differ in the interrupt
handler (`pci230_interrupt()`) itself when it temporarily clears bits in
the interrupt enable register and the `ier` member in order to unlatch
them in hardware, but leaves the `int_en` member alone.  They also
differ in `pci230_ai_stop()` and `pci230_ao_stop()` which clear bits in
the `int_en` member and wait for the interrupt handler to finish before
copying the value to the `ier` member and the interrupt enable register.

Simplify the handling a bit, by making the `ier` member take on the role
of the `int_en` member, and allowing the value to differ from the
interrupt enable register while the interrupt handler is running.
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 return type of `pci230_handle_ao_fifo()` from `int` to
`bool`.  A return value of `true` indicates the AO command is still
running.
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>

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>

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>

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>

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>

Some counter channels may be required for AI commands and AO commands.
Depending on how the commands are set up, it may not be possible to run
both at the same time, so we keep some state and code to find out if the
required resources are busy or not.

The existing code is a bit unwieldy - the code for claiming resources
involves two `for` loops for example.  Rewrite it to make it simpler.

The new code just has a bit-mask value for each shared resource (counter
channels), and an array indexed by resource "owners" (AI and AO
commands), so the code for claiming resources now just has a single loop
that checks that none of the other owners have claimed the wanted
resources.

Rename the functions involved, because the old names involving 'put' and
'get' suggested some sort of usage counting.
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 `state` member of `struct pci230_private` is used with the atomic
bit-op functions and has a couple of bits defined, `AI_CMD_STARTED` and
`AO_CMD_STARTED`.  Spin-locks are used to protect the clearing of these
bits and other stuff.  No special protection is used for setting these
bits.  Replace the `state` member with a couple of new, single-bit
bitfield members, `ai_cmd_started` and `ao_cmd_started` to save some
space.
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 `intr_running` member of `struct pci230_private` into a
single-bit bitfield of type `bool` to save a bit of space.
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>

Use the inline `comedi_range_is_bipolar()` function from "comedidev.h"
to decide whether a range is bipolar or unipolar instead of using the
local static arrays `pci230_ai_bipolar[]` and `pci230_ao_bipolar[]`
which can then be removed.

Change the types of the `ai_bipolar` and `ao_bipolar` members of `struct
pci230_private` to `bool` to match the return value of
`comedi_range_is_bipolar()` and change them into single-bit bitfields to
save a bit of space.  Also change the type and name of some local
variables in `pci230_ai_check_chanlist()` that hold the result of
`comedi_range_is_bipolar()`.
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>

Most functions in "amplc_pci230" are named with the prefix `pci230_`,
apart from one or two that have the prefix `amplc_pci230_` and a few
odd-balls with no particular prefix.  Rename the ones without a prefix
for consistency.
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 AI subdevice "insn_read" handler function `pci230_ai_rinsn()`
to `pci230_ai_insn_read()` for consistency.
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>

Some functions in "amplc_pci230.c" are declared `inline`.  Remove the
`inline` specifiers and let the compiler do what it wants with 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>

`pci230_ai_read()` reads a sample from the ADC data register and
converts it to a comedi sample value.  The AI sample may have 12 or 16
bits of resolution, depending on the board type, but 12-bit sample
values are in bits 15 to 4 of the register.  The hardware value is
signed, 2's complement if set to a bipolar mode, or unsigned, straight
binary if set to a unipolar mode.  To convert to a Comedi sample value
it may need shifting right by 4 bits, and the top bit of the sample
value may need to be toggled.

Simplify the existing code by doing the 2's complement to straight
binary conversion before the shift.  That way, it is always bit 15 that
is inverted regardless of the resolution.
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>

`pci230_ao_mangle_datum()` converts comedi sample values for the AO
subdevice to hardware register values.  The comedi sample value will be
an unsigned value in the range 0 to 4095 (assuming 12-bit resolution).
The hardware wants the value shifted so the m.s. bit of the sample in in
bit 15.  If set to a bipolar range, it also expects a 2's complement
value, so the top bit of the sample value needs to be inverted in that
case.

Simplify the existing code by doing the 2's complement conversion after
the shift.  That way, it is always bit 15 that is inverted regardless of
the resolution.
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 `ai_bits`, `ao_bits`, and `min_hwver` members of `struct
pci230_board` are only set to small, non-negative values, so make them
`unsigned char`.  The `have_dio` member is used as a boolean so change
it to a bitfield of type `bool`.
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 PCI230(+) has an AO subdevice with 2 channels, but the PCI260(+) has
none.

The `ao_chans` member of `struct pci230_board` indicates whether the
board has an AO subdevice and the number of AO channels.  The
`ao_bits` member indicates the AO sample width in bits and will only be
non-zero for boards with an AO subdevice.

Use `ao_bits` to indicate whether the board has an AO subdevice.  If it
has, assume the the number of AO channels is 2.  Then the `ao_chans`
member becomes redundant and can be removed.
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>

All boards supported by the "amplc_pci230" driver have 16 AI channels,
so the `ai_chans` member of `struct pci230_board` is superfluous and can
be removed.
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>

`pci230_alloc_private()` is now only called from `pci230_auto_attach()`
to allocate private device storage and initialize various spin-lock
members therein.  Absorb the body of `pci230_alloc_private()` into
`pci230_auto_attach()` itself.
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 comedi core module calls `comedi_set_hw_dev()` to associate the
hardware `struct device` with the `struct comedi_device` before it calls
the comedi driver's "auto_attach" hook `pci230_auto_attach()`.  There is
no need for `pci230_auto_attach()` to call `comedi_set_hw_dev()` itself,
so remove the call.
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>

`pci230_attach_common()` is now only called from `pci230_auto_attach()`,
so absorb it into that 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>

Since the comedi driver's "detach`" handler `pci230_detach()` now merely
calls `comedi_pci_detach()` with the same parameter, use
`comedi_pci_detach()` itself as the "detach" handler.
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>

This driver no longer supports a "legacy" attach mechanism that searches
for a suitable PCI device and increments it's reference count, but since
the common "detach" handler `pci230_detach()` still has a left-over
`pci_dev_put()`, a matching `pci_dev_get()` is needed in the
"auto_attach" handler `pci230_auto_attach()`.  There is no longer any
reason to "get" and "put" the PCI device, so those calls can be removed.
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 "amplc_pci230" driver currently retains the legacy attach mechanism
to allow devices to be attached manually via the `COMEDI_DEVCONFIG`
ioctl.  The only real use for this is to pretend that a PCI230+ or
PCI260+ is a PCI230 or PCI260 for backwards compatibility, as they have
different number of bits of resolution on the AI subdevice.  Since the
card would be automatically configured as a PCI230+ or PCI260+ at PCI
probe time anyway, hopefully any users who want it to appear as a PCI230
or PCI260 would have got tired of removing the automatically configured
device and configuring it manually by now and will have updated their
software to cope with the PCI230+ or PCI260+.

Get rid of the legacy attach mechanism by removing the Comedi driver
"attach" handler `pci230_attach()` and associated code.  Also remove the
"wildcard" entry from the board table `pci230_boards[]` as it is no
longer needed.  Don't bother initializing the `board_name`, `offset`,
and `num_names` members of `struct comedi_driver amplc_pci230_driver`
any longer as they are only needed when configuring the device manually.
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>

Where the only thing in an `else { ... }` block is another `if`
statement, collapse it to an `else if {` block where it makes sense to
do so.
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>

Remove some pairs of parentheses that don't really improve readability.
Also, reduce the amount of leading whitespace in a few places.
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>