Commit e42151f9 authored by H Hartley Sweeten's avatar H Hartley Sweeten Committed by Greg Kroah-Hartman
Browse files

staging: comedi: cb_pcidas: use subdevice readback for 'dac08_value' 



Use the comedi_subdevice 'readback' member and the core provided (*insn_read)
to handle the readback of the write-only dac08 calib subdevice. Remove the
then unused 'dac08_value' member from the private data.

The dac08 calib subdevice only has one channel. For consistency in the driver,
modify the subdevice init so that a loop is used to initialize the channels and
readback values.

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 9c034da1

drivers/staging/comedi/drivers/cb_pcidas.c

+13 −19
Original line number Diff line number Diff line
@@ -356,7 +356,6 @@ struct cb_pcidas_private { 
	/* divisors of master clock for analog output pacing */

	unsigned int ao_divisor1;

	unsigned int ao_divisor2;

	unsigned int dac08_value;

	unsigned int calibration_source;

};
@@ -650,31 +649,20 @@ static int cb_pcidas_dac08_insn_write(struct comedi_device *dev, 
				      struct comedi_insn *insn,

				      unsigned int *data)

{

	struct cb_pcidas_private *devpriv = dev->private;

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



	if (insn->n) {

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



		if (devpriv->dac08_value != val) {

		if (s->readback[chan] != val) {

			dac08_write(dev, val);

			devpriv->dac08_value = val;

			s->readback[chan] = val;

		}

	}



	return insn->n;

}



static int dac08_read_insn(struct comedi_device *dev,

			   struct comedi_subdevice *s, struct comedi_insn *insn,

			   unsigned int *data)

{

	struct cb_pcidas_private *devpriv = dev->private;



	data[0] = devpriv->dac08_value;



	return 1;

}



static int trimpot_7376_write(struct comedi_device *dev, uint8_t value)

{

	struct cb_pcidas_private *devpriv = dev->private;
@@ -1531,11 +1519,17 @@ static int cb_pcidas_auto_attach(struct comedi_device *dev, 
		s->type = COMEDI_SUBD_CALIB;

		s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_INTERNAL;

		s->n_chan = NUM_CHANNELS_DAC08;

		s->insn_read = dac08_read_insn;

		s->insn_write = cb_pcidas_dac08_insn_write;

		s->maxdata = 0xff;

		s->insn_write = cb_pcidas_dac08_insn_write;



		ret = comedi_alloc_subdev_readback(s);

		if (ret)

			return ret;



		for (i = 0; i < s->n_chan; i++) {

			dac08_write(dev, s->maxdata / 2);

		devpriv->dac08_value = s->maxdata / 2;

			s->readback[i] = s->maxdata / 2;

		}

	} else

		s->type = COMEDI_SUBD_UNUSED;