Commit f8990d08 authored by H Hartley Sweeten's avatar H Hartley Sweeten Committed by Greg Kroah-Hartman
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staging: comedi: ni_at_ao: use subdevice readback for 'caldac' 



Use the comedi_subdevice 'readback' member and the core provided (*insn_read)
to handle the readback of the write-only caldac subdevice. Remove the then unused
'caldac' member from the private data.

Tidy up atao_calib_insn_write().

Signed-off-by: default avatarH Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: default avatarIan Abbott <abbotti@mev.co.uk>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent e42151f9

drivers/staging/comedi/drivers/ni_at_ao.c

+21 −34
Original line number Diff line number Diff line
@@ -244,47 +244,31 @@ static int atao_calib_insn_write(struct comedi_device *dev, 
				 struct comedi_insn *insn,

				 unsigned int *data)

{

	struct atao_private *devpriv = dev->private;

	unsigned int chan = CR_CHAN(insn->chanspec);

	unsigned int bitstring;

	unsigned int val;

	int bit;



	if (insn->n == 0)

		return 0;



	devpriv->caldac[chan] = data[insn->n - 1] & s->maxdata;

	if (insn->n) {

		unsigned int val = data[insn->n - 1];

		unsigned int bitstring = ((chan & 0x7) << 8) | val;

		unsigned int bits;

		int bit;



		/* write the channel and last data value to the caldac */

	bitstring = ((chan & 0x7) << 8) | devpriv->caldac[chan];



		/* clock the bitstring to the caldac; MSB -> LSB */

		for (bit = 1 << 10; bit; bit >>= 1) {

		val = (bit & bitstring) ? ATAO_CFG2_SDATA : 0;

			bits = (bit & bitstring) ? ATAO_CFG2_SDATA : 0;



		outw(val, dev->iobase + ATAO_CFG2_REG);

		outw(val | ATAO_CFG2_SCLK, dev->iobase + ATAO_CFG2_REG);

			outw(bits, dev->iobase + ATAO_CFG2_REG);

			outw(bits | ATAO_CFG2_SCLK,

			     dev->iobase + ATAO_CFG2_REG);

		}



		/* strobe the caldac to load the value */

		outw(ATAO_CFG2_CALLD(chan), dev->iobase + ATAO_CFG2_REG);

		outw(ATAO_CFG2_CALLD_NOP, dev->iobase + ATAO_CFG2_REG);



	return insn->n;

		s->readback[chan] = val;

	}



static int atao_calib_insn_read(struct comedi_device *dev,

				struct comedi_subdevice *s,

				struct comedi_insn *insn,

				unsigned int *data)

{

	struct atao_private *devpriv = dev->private;

	unsigned int chan = CR_CHAN(insn->chanspec);

	int i;



	for (i = 0; i < insn->n; i++)

		data[i] = devpriv->caldac[chan];



	return insn->n;

}
@@ -365,9 +349,12 @@ static int atao_attach(struct comedi_device *dev, struct comedi_devconfig *it) 
	s->subdev_flags	= SDF_WRITABLE | SDF_INTERNAL;

	s->n_chan	= (board->n_ao_chans * 2) + 1;

	s->maxdata	= 0xff;

	s->insn_read	= atao_calib_insn_read;

	s->insn_write	= atao_calib_insn_write;



	ret = comedi_alloc_subdev_readback(s);

	if (ret)

		return ret;



	/* EEPROM subdevice */

	s = &dev->subdevices[3];

	s->type		= COMEDI_SUBD_UNUSED;