Fix checkpatch issue: "CHECK: usleep_range is preferred over udelay; see
Documentation/timers/timers-howto.txt".  `udelay()` is only used in the
firmware upload process.  Replace them with `usleep_range()` with a
reasonable upper limit.
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 returns two's complement values for the analog input
samples. These need to be converted to the unsigned binary format
that the comedi core expects. Introduce a helper function to handle
this.
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 irq handler does not need to manually stop conversions and disable
interrupts when "end-of-acquisition", "error", or "overflow" events are
detected. The comedi_handle_events() will call the subdevice (*cancel)
when these are detected and stop the acquisition.
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 white space to the analog output subdevice
initialization.
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>

There is no real reason to reset the board when detaching. The comedi core
will ensure that any commands are canceled before the detach.

But the PLX interrupts should be disabled.
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>

Currently me4000_reset() always enables the PLX interrupt. Move the
enable of the interrupt into me4000_auto_attach() and only do the
enable if we actually have and irq.

Make sure the PLX interrupt is disabled in me4000_reset() before we
try to request the irq.
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 to stop any ai conversions and reset the
ai control register. This consolidates the common code in me4000_reset()
and me4000_ai_cancel().

Use the new helper in the ai (*insn_read) to ensure that the ai control
register is set to a known state after reading the samples.

The ai control register will now always be '0' after the (*cancel) of
a command or doing an (*insn_read). Knowing this the programming of
the register for single acquisition mode in the (*insn_read) can be
simplified.
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>

Reset the analog input control register after ensuring that any active
conversions have been stopped. This mimics what the ai subdevice (*cancel)
does.
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 core ensures that the subdevice is not busy before it allows
starting a new command. The subdevice (*cancel) is called when the
subdevice is set to not busy. In this driver the me4000_ai_cancel()
is the ai (*cancel) so the extra call in the ai (*do_cmd) is not
necessary. Remove it.
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 me4000_ai_cancel() already reset this register.
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 STOP and IMMEDIATE_STOP bits in the ME4000_AI_CTRL_REG should be set,
not cleared, to stop any running conversions.
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 always returns 0 and the return value is never checked.
Just return void.
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 only called by me4000_ai_do_cmd(). Absorb it.
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 never fails and it's only called by me4000_ai_do_cmd().

Absorb it and remove the unnecessary failure check.
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 (*do_cmd_test) validates the trigger sources in Step 2b to ensure
that they are compatible. Save the 'ai_ctrl_mode' that will be used in the
private data so that ai_prepare(), which is called by the ai (*do_cmd),
does not have to recheck the sources in order to figure it out.

Also, tidy up the stop trigger checks so that the ME4000_AI_CTRL_HF_IRQ
bit is set in the common code path.
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 (*do_cmd_test) calls me4000_ai_round_cmd_args() to calculate the
timing values needed to the command. The the command test passes, the
core will then call the ai (*do_cmd) which then has to call
me4000_ai_round_cmd_args() again in order to get the same values to
pass to ai_prepare() in order to program the timing.

Add members to the private data to allow the (*do_cmd_test) to calculate
and save to values needed by ai_prepare().
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 always succeeds. Change the return type to void and
remove the unnecessary error check in me4000_ai_do_cmd().

Move the function call in me4000_ai_do_cmd_test() from before Step 1
to Step 3 where the arguments are validated. There is no reason to
get the values if the previous steps fail.

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>

Use the BIT() marco to define the bits of this register.

For aesthetics, rename all the defines to remove the '_BIT' from the
name.
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 BIT() marco to define the bits of this register.

For aesthetics, rename all the defines to remove the '_BIT' from the
name.
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 BIT() marco to define the bits of this register.

For aesthetics, rename all the defines to remove the '_BIT' from the
name.
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 BIT() marco to define the bits of this register.

For aesthetics, rename all the defines to remove the '_BIT' from the
name.
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 BIT() marco to define the bits of this register.

For aesthetics, rename all the defines to remove the '_BIT' from the
name.
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 BIT() marco to define the bits of this register.

For aesthetics, rename all the defines to remove the '_BIT' from the
name. Also, use ME4000_AI_STATUS_REG instead of ME4000_AI_CTRL_REG
when reading the register (they happen to be the same).
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 check the range type instead of relying on the
value. For aesthetics, rename the local variable used for the range.
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 chanspec channel, range, and aref are unsigned int values. Use the
correct types when extracting 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>

The coemdi (*insn_read) functions are supposed to read insn->n values
from the hardware. Make this function work like the core expects.

Use the comedi_offset_munge() helper to munge the two's complement
values to offset binary.
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 comedi_timeout() helper to busy-wait for the analog input end-of-
conversion instead of the udelay().
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 BIT() macro to define the bits of this register.
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 this function so it has namespace associated with the driver.

The last entry of the chanlist needs the ME4000_AI_LIST_LAST_ENTRY bit
set to end the list. Fix the function and tidy if up a bit.
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_lrange table for the analog inputs is inverted compared
to the values that need to be written to the ME4000_AI_CHANNEL_LIST_REG
to select the range.

Create a macro, ME4000_AI_LIST_RANGE(), to handle the inversion. Remove
the old defines and simplify the code a bit.
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 define evaluates to 0 and is OR'ed with the 'entry' value that is
written to the ME4000_AI_CHANNEL_LIST_REG when the channel aref is a
single-ended type (AREF_GROUND or AREF_COMMON). OR'ing a zero value is
pretty silly, just remove it.

Remove the switch() in me4000_ai_insn_read() to simplify the 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>

In comedi drivers the local variable used for the dev->private pointer is
normally named 'devpriv'. For aesthetics, rename the variables in this
driver. Also, rename the struct to follow the norm.
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>

Some of the boards supported by this driver can do analog input sample &
hold on 8 of the channels. The 'ai_sh_nchan' member of the boardinfo is
used to indicate which boards support this feature. To save a bit of space,
convert this member to a bit-field, 'can_do_sh_ai'. Note, this feature is
not currently supported.
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 always '4' for the boards that have an
analog output FIFO. Covert it to a bit-field, 'has_ao_fifo', to save a
bit of space.
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 the boards that have analog output capability, there are always
4 analog output channels. Convert the 'ao_nchan' member of the boardinfo
into a bit-field, 'has_ao', to save a bit of space and set the analog
output subdevice 'n_chan' to 4 when supported.
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 only used as a flag indicating that the
board supports differential analog inputs. Convert the member to a bit-
field to save a bit of space. For aesthetics, rename the member to
'can_do_diff_ai'.
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 boardinfo 'has_counter' and 'ai_trig_analog' flags into
bit-fields to save a bit of space.
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 maximum differential channel is half the subdevice 'n_chan'. Use
that instead and remove the need for the 'board' variable.

Also, the comedi core does no validate the aref flags. Add a check
to ensure that the subdevice actually supports the AREF_DIFF 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>

The 'board' pointer is only used in this function to verify that the
'chan' is valid for an aref of AREF_DIFF. For differential inputs, the
maximum channel is half the subdevice 'n_chan'. Use that instead and
remove the 'board' variable.

Also, the comedi core does not validate the aref flags. Add a check
to ensure that the subdevice actually supports the AREF_DIFF 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>

The comedi core validates that the 'chan' is valid for the subdevice
before calling the (*insn_read) operation. Remove the unnecessary check.
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>