For aesthetics, redefine the bits in the mode register that enable interrupts
and scanning.
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 is not used in the driver. 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>

For aesthetics, remove this define and just use ~APCI3120_ENABLE_EOS_INT.
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, remove this define and just use ~APCI3120_ENABLE_EOC_INT.
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, remove this define and just use ~APCI3120_ENABLE_TIMER_INT.
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, remove this define and just use ~APCI3120_ENABLE_WATCHDOG.
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, remove this define and just use ~APCI3120_ENABLE_TIMER_COUNTER.
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 mask value is the same as APCI3120_DISABLE_TIMER_COUNTER. Use that
instead and remove the "magic" value.
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 devpriv->mode is set to '0' at the start of apci3120_ai_insn_read() and
apci3120_cyclic_ai(). There is no need to clear any of the bits or do any
of the additional writes of those cleared bits.
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 CamelCase member of the private data and tidy up the mask/set
of its bits.
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 APCI3120_DISABLE_ALL_INTERRUPT define is a mask value used to clear bits
in devpriv->b_ModeSelectRegister to disable the interrupt sources. Writing this
value directly sets unintended bits.

Just set the devpriv->b_ModeSelectRegister to '0' and write that to the 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>

At the start of apci3120_ai_insn_read() the devpriv->b_ModeSelectRegister is set
to '0'. Remove the unnecessary masking to clear the interrupt enable bits.
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>

Move the analog input comedi_lrange table from the included hwdrv_apci3120.c
source file to the main driver source file.
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>

A dummy read of APCI3120_TIMER_MODE_REG resets the analog input FIFO. Introduce
a helper function to clarify this.

It's not necessary to do a dummy read of the FIFO (base + 0) before reseting it.
Remove the unnecessary dummy reads.

The APCI3120_TIMER_MODE_REG is a 16-bit register. This fixes a couple 8-bit reads.
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 parameter is always passed as '0'. Remove it and refactor 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>

Define the chanlist register and its bits and tidy up the programming
of the scan chanlist.
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 scan sequence does not need to be reset when the driver is attached. Remove
the code in apci3120_reset() that does 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>

A dummy read of APCI3120_CTR0_REG clears the timer 2 interrupt. Introduce a
helper function to clarify 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>

Move this helper function from the included source file into the main driver
source file.
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>

Move this helper function from the included source file into the main driver
source file.
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, rename this define.
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 wrong define is being used to disable the gate to stop timer 2 in this
function.

Use the apci3120_timer_enable() helper to properly disable the timer.
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 enable/disable a timer.

The disable of timers 0 and 1 in apci3120_interrupt() is probably not needed.
For now use the helper function to make sure the devpriv->ctrl bits are cleared
correctly to disable the timers.
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>

Merge these two functions and use an 'enable' parameter to determine if the
external trigger needs to be enabled or disabled.

This function always succeeds and the callers don't check the return. Change
the return type to 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>

For aesthetics, rename this define.
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, replace these defines with a macro that returns the
correct bit needed to set the gate bit to enable a timer.
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, remove these defines and just use ~APCI3120_ENABLE_TIMER[012].
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 apci3120_setup_chan_list() function sets devpriv->ctrl to the scan length
(PR) and scan start (PA) values and writes the value to the register. There is
no need to mask the value first.

The apci3120_ai_insn_read() function calles apci3120_setup_chan_list(). There
is no need to clear devpriv->ctrl first or clear any additional bits and write
the register again. This also fixes an incorrect use of APCI3120_DISABLE_TIMER0
to disable the timer.

apci3120_cyclic_ai() also calls apci3120_setup_chan_list() so it does not need
to clear devpriv->ctrl or clear any addidional bits and write the register.

Update the comments in apci3120_reset() and apci3120_cancel().
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 CamelCase member of the private data and tidy up the mask/set
of its bits.
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>

Move the timer read/write and set mode helpers from the included source
file into the main driver source file.
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 set the operation mode of a timer.
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 a macro that returns the mask of the timer_mode bits for a given
timer. Use the macro to remove the "magic" values used to clear the bits.
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 CamelCase member of the private data and tidy up the mask/set
of its bits.
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, rename this register offset.
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 APCI3120_DISABLE_ALL_TIMER define define is not needed, and it's used
incorrectly in apci3120_cancel(). The define is a mask of the bits needed
to disable the counters. Writing the value directly sets unintended bits.

Prior to writing the value, the 'devpriv->us_OutputRegister' is set to 0
and written to the register. This disables all the timers and the external
trigger.

Remove the unnecessary apci3120_exttrig_disable() call as well as the write
of APCI3120_DISABLE_ALL_TIMER.

In apci3120_interrupt(), remove the unnecessary mask and write to disable
all the timers. The COMEDI_CB_EOA event will cause the core to call the
(*cancel) operation which will disable the timers.

Remove the unused define.
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 CTR0 register in the main driver source file and remove all
the old defines in hwrdv_apci3120.c.

For aesthetics, save the raw digital output state (devpriv->do_bits) in
the digital output (*insn_bits) function and use a macro to set them when
reading/writing a timer.

Use the CTR0 register define in the digital output (*insn_bits) function
and remove the current register define.
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 select a timer and read a value from 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>

Introduce a helper function to select a timer and write a value to 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>

Rename this CamelCase member of 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>

The timer divisor calculations in this driver are over complicated.

There are three timers on the board. They all use the same base clock
with a fixed prescaler for each timer. The base clock used depends on
the board version and type:

  APCI-3120 Rev A boards OSC = 14.29MHz base clock (~70ns)
  APCI-3120 Rev B boards OSC = 20MHz base clock (50ns)
  APCI-3001 boards OSC = 20MHz base clock (50ns)

The prescalers for each timer are:

  Timer 0 CLK = OSC/10
  Timer 1 CLK = OSC/1000
  Timer 2 CLK = OSC/1000

Add a new member to the private data, 'osc_base', to hold the base clock
time. Set this member during the board attach.

Introduce a helper function to calculate the divisor needed to generate
a nanosecond time with a given timer.

Use the new helper function in the driver to clarify 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>