Fix the checkpatch.pl issues:
WARNING: Block comments use a trailing */ on a separate line
WARNING: line over 80 characters
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 comments are just added cruft. Remove them.
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 step of the (*do_cmdtest) fixes the timing arguments when the
cmd->convert_src is TRIG_TIMER. The code is compact but it's a bit
hard to understand the "burst mode" vs. "non burst mode" (i.e. paced)
timing.

Clarify the fixup by splitting it into separate functions to check
the arguments based on if the command is doing 'paced' or 'burst'
timing. Add some comments to clarify the fixups.

This also fixes a minor issue with the 'burst' timing. When the
cmd->scan_begin_src is also TRIG_TIMER the pacer clock is used to
start each scan. The cmd->scan_begin_arg specifies the scan time.
The minimum (not maximum) value for this time must be large enough
for the 'burst' conversion time to sample all the channels.

The current 'max' check limits the scan time to the minimum time
(i.e. the max conversion speed).
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 comments about the members of the private data are not really
necessary and removing them fixes a couple checkpatch.pl issues.
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 information into the comedi comment block.
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>

Fix the checkpatch.pl issue:
CHECK: Prefer kernel type 'u16' over 'uint16_t'

Change the type to 'unsigned short' as that is more typical in comedi
drivers.

Use sizeof(*p) instead of sizeof(type) when allocation the buffer.
Also fix the checkpatch.pl issue:
WARNING: line over 80 characters
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>

Tidy up these multi-line comments to fix the checkpatch.pl issues:
WARNING: Block comments use * on subsequent lines
WARNING: line over 80 characters
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 comedi_device spinlock is used to protect the indirect addressing
selected by the DAS1800_SELECT register. It also prevents races between
the interrupt handler and the analog input (*poll).

Update the comments to make this clear.
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>

Absorb this helper function into the analog input (*do_cmd).
For aesthetics, convert the switch code into if/else.
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>

Use the helper function to handle the busywaiting for the analog
input conversion to complete.
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>

Refactor this function so it can be used to program the chanlist for
the analog input (*do_cmd) and (*insn_read).

Rename the function so it has 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>

Absorb this helper function into the analog input (*do_cmd).
For aesthetics, convert the switch code into if/else.
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>

Introduce a helper function for the common code needed to set the
control c register bits for a channel specification.
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>

Use the core provided readback support to allow reading back the last
value written to the analog output channels.
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 value is compared against the unsigned int cmd->convert_arg to
check the minimum value (max speed) for the analog input conversion
timing.

For aesthetics, change the type to match the cmd->convert_arg type.
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 "hc" type boards have 64 analog input channels with a 64
entry queue. All the others have 16 channels and a 256 entry
queue.

EXP-1800 expansion boards can be used to increase the number
of analog inputs on the 16 channel boards, 16 channels per
EXP-1800, for a total of 256 channels.

Remove the 'qram_len' member of the boardinfo and use the
'id' member to determine the number of channels.

Add a comment about the number of channels and the unclear
mapping of the channels when EXP-1800 boards are used.
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 boards supported by this driver have analog inputs with gains
of 1, 10, 50, and 250 ("01" type) or 1, 2, 4, and 8 ("02" type).
Unfortunately, the "01"/"02" type cannot be determined from the
boards id or by probing.

Replace the 'range_ai' member of the boardinfo with a bit-field flag,
'is_01_series' and only set it for the "01" type boards. Remove the
unnecessary initialization for the "02" type boards.

For aesthetics, rename the comedi_lrange arrays and document the gain.
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 "da" and "hc" type boards have normal analog outputs. The
"ao" type boards have move advanced analog outputs with waveform
generation capability.

Remove the 'ao_ability' member of the boardinfo and use the
'id' member to determine if the subdevice should be initialized.

The "ao" waveform analog outputs are not currently supported.
For aesthetics, add an else if for the initialization of the
subdevice for these boards.
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 "st-da" board types have 4 analog output channels. All other
board types, with analog outputs, only have 2 channels.

Remove the 'ao_n_chan' member of the boardinfo and use the
'id' member to determine the subdevice 'n_chan'.
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 (*insn_write) functions are supposed to write insn->n values to the
specified channel. Tidy up this function and make it work like the core
expects.
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 current code used to initialize the analog outputs only sets the
last channel. The other channels will be reloaded with the last value
that was written to them.

Move the code into the subdevice init and properly initialize all the
channels to 0V.
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 "hc" type boards have 8 digtial outputs. All other board
types have 4.

Remove the 'do_n_chan' member of the boardinfo and use the
'id' member to determine the subdevice 'n_chan'.
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 "hr" type boards have 16-bit analog inputs and outputs.
All other board types have 12-bit.

Remove the 'resolution' member of the boardinfo and use the
'id' member to determine the subdevices 'maxdata'.
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 analog outputs expect 2's complement data. For aesthetics, use
the helper function to handle the munging instead of depending on
the boardinfo 'resolution'.
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 "hc" type boards do not support common mode analog inputs
all the other board types do.

Remove the unnecessary member from the boardinfo and use the
'id' member to determine if the SDF_COMMON flag should be set
for 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>

Refactor das1800_probe() to return an errno instead of the boardinfo
pointer.

Add the board 'id' to the boardinfo to tidy up this function to clarify
the sanity check when the user provided a board name when trying to
attach to the driver.

Currently when this function probes for a boardinfo based on the board
id it returns the wrong boardinfo for the "st-da" and "hr-da" types.
This causes the analog input subdevice for those boards to not be
available. Fix the probe so that a proper boardinfo is used.
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 some whitespace to the boardinfo array.
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 some whitespace to the subdevice init and rename
the subdevice support functions.
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 some whitespace to the subdevice init and rename
the (*insn_write) 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>

For aesthetics, add some whitespace to the subdevice init and rename
the (*insn_bits) 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>

For aesthetics, add some whitespace to the subdevice init and rename
the (*insn_bits) 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>

Rename the enum value to fix the checkpatch.pl issue:
CHECK: Avoid CamelCase: <MARB_PCIv21_MODE>
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>

Tidy up the defines to fix the checkpatch.pl issues:
CHECK: Prefer using the BIT macro
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>

Tidy up the comments to fix the checkpatch.pl isses:
WARNING: Block comments use * on subsequent lines
WARNING: line over 80 characters
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>

Tidy up the block comments to fix the checkpatch.pl issues:
WARNING: Block comments use * on subsequent lines
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>

Change the type to fix the checkpatch.pl issues.
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>

Change the types to fix the checkpatch.pl issues.
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 "da" type boards all have 4 analog outputs. Fix the boardinfo
for the das-1801st-da.
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 analog input samples are 2's complement when the inputs are configured
for bipolar ranges and offset binary when they are unipolar ranges. For
bipolar ranges the sample needs to be munged to the offset binary format
that comedi uses.

The (*insn_read) does the munging correctly but the async command support
incorrectly munges the data for both bipolar and unipolar ranges when
reading the remaining samples from the fifo in das1800_handle_fifo_not_empty().

Add a (*munge) function to the analog input subdevice so that the samples
are correctly munged when they are added to the async buffer by
comedi_buf_write_samples(). Add a flag to the private data and set it in
the (*do_cmd) so that the munging is only done for bipolar ranges.

Clarify the code by using the core helper functions to check the range and
do the munging.
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>

DMA is optional with this driver. If it was not enabled the devpriv->dma
pointer will be NULL.

Fix the possible NULL pointer dereference when trying to disable the DMA
channels in das1800_ai_cancel() and tidy up the comments to fix the
checkpatch.pl issues:
WARNING: line over 80 characters

It's probably harmless in das1800_ai_setup_dma() because the 'desc' pointer
will not be used if DMA is disabled but fix it there also.

Fixes: 99dfc335 ("staging: comedi: das1800: remove depends on ISA_DMA_API limitation")
Cc: <stable@vger.kernel.org> # 4.0+
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>