Change the MODULE_DESCRIPTION to something useful instead of 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>

Use the dev->read_subdev to get the comedi_subdevice instead of accessing
the dev->subdevices array directly.
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 aesthetic reasons, rename this 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 aesthetic reasons, reorder the #include list.
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 multi-line comments to follow the CodingStyle.
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>

Add some whitespace to tidy up the subdevice init.
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>

Interrupt support in this driver is optional. Don't fail the attach of the
board if the request_irq() fails.

Only allocate and setup the subdevice for the interrupt if the request_irq()
was successful.
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 enabled state of the interrupt can be checked by reading the control
register.

Remove 'enabled_irq' from the private data.

Since the private data is now empty, remove it completely and remove the
allocation of it in parport_attach().
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 control register for the parallel port is readable so there is no need
to cache the current value in the private data.
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 to better describe it's use.

Use comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state.
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 to better describe it's use.

Tidy it up to follow the normal comedi (*insn_bits) for DI 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>

This is the (*insn_config) function for a DIO subdevice. It should be
using the data[0] value as the "instruction" to perform on the subdevice.

Use the comedi_dio_insn_config() helper to properly handle instructions.

Also, rename the function to better describe it's use.
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 to better describe it's use.

Use comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state.
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 subdevice s->state to hold the current state of the data register
outputs instead of carrying it in the private data.
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 register map defines to better describe the hardware.

Add defines for the control register bits that enable the irq and
change the direction of the data register. This gets rid of the
"magic" numbers.

Remove PARPORT_SIZE, it's only used when requesting the i/o region
with comedi_request_region().
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 extra mask used to only update the channels configured as outputs is
not necessary in this driver. Remove it and use comedi_dio_update_state()
to handle the boilerplate code to update the subdevice s->state.
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 extra mask used to only update the channels configured as outputs is
not necessary in this driver. Remove it and use comedi_dio_update_state()
to handle the boilerplate code to update the subdevice s->state.
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 extra mask used to only update the channels configured as outputs is
not necessary in this driver. Remove it and use comedi_dio_update_state()
to handle the boilerplate code to update the subdevice s->state.
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 extra mask used to only update the channels configured as outputs is
not necessary in this driver. Remove it and use comedi_dio_update_state()
to handle the boilerplate code to update the subdevice s->state.
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 extra mask used to only update the channels configured as outputs is
not necessary in this driver. Remove it and use comedi_dio_update_state()
to handle the boilerplate code to update the subdevice s->state.
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 extra mask used to only update the channels configured as outputs is
not necessary in this driver. Remove it and use comedi_dio_update_state()
to handle the boilerplate code to update the subdevice s->state.
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 comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state.
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 comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state.

Also, fix a bug where the state of the channels is returned in data[0].
The comedi core expects it to be returned in data[1].
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 subdevice 'state' variable instead of carrying the state of
the output channels in the private data.

Use comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state.
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 subdevice 'state' variable instead of carrying the state of
the output channels in the private data.

Use comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state.
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 subdevice 'state' variable instead of carrying the state of
the output channels in the private data.

Use comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state.
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 subdevice 'state' variable instead of having to calculate the
current state based on the do_mux_bits in the private data.

Use comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state.
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 subdevice 'state' variable instead of carrying the state of
the output channels in the private data.

Use comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state.
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 comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state.

Tidy up the vmk80xx_do_insn_bits() function 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>

Use comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state.

Remove the DEBUG_DIO, its just added noise.
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 comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state for more complex cases where the hardware is only
updated based on the 'mask' of the channels that are modified.
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 comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state for simple cases where the hardware is updated
when any channel is modified.

Also, fix a bug in the amplc_pc263 and amplc_pci263 drivers where the
current state is not returned in data[1].
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 comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state.

These drivers always need to update the hardware in order to update
the i/o configuration regardless of if the state has changed.
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>

Convert this driver to use the comedi_dio_update_state() helper
function.

Tidy up the comments to reflect the new 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>

The (*insn_bits) functions for DIO and DO subdevices typically use
the subdevice 's->state' to hold the current state of the output
channels. The 'insn' passed to these functions, INSN_BITS, specifies
two parameters passed in the 'data'.

  data[0] = 'mask', the channels to update
  data[1] = 'bits', the new state for the channels

Introduce a helper function to handle the boilerplate used to
update the internal state.

Note that the 'mask' is filtered by the 'chanmask' of the channels
actually supported by the subdevice. This is used to protect any
non-channel related bits that are stored in the subdevice state.
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 subdevice 'io_bits' is a bit mask of the i/o configuration for
digital subdevices. '0' values indicate that a channel is configured
as an input and '1' values that the channel is an output. Since the
subdevice data is kzalloc()'d, all channels default as inputs.

Modify __comedi_device_postconfig() so that 'io_bits' is correctly
initialized for Digital Output subdevices.

Remove all the unnecessary initializations of 's->io_bits' from the
drivers. Also, remove the unnecessary initialization of the 's->state'.
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>

Please don't flame me :) I'm getting my feet wet with kernel contribution.
One example I saw in a video by GKH suggested cleaning up coding style as a good first commit.
Signed-off-by: Sean Williams <unixed@gmail.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Use the core provided helper function instead of duplicating it as
a private 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>

Use the core provided helper function instead of duplicating it as
a private 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>

Sorry. I thought that this would be a nice easy class to document fully.
Turns out I was very wrong - I will have to research the Linux alarm and
timer subsystem one day next week and try again.

Here is what I started out with, anyway. It's not much, but it's better
than nothing!
Signed-off-by: Cruz Julian Bishop <cruzjbishop@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>