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

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_value' member from 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>
This commit is contained in:
H Hartley Sweeten 2014-11-20 15:07:25 -07:00 committed by Greg Kroah-Hartman
parent f52e5e44a9
commit 3f5ced0d02

View file

@ -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 caldac_value[NUM_CHANNELS_8800];
unsigned int trimpot_value[NUM_CHANNELS_8402];
unsigned int dac08_value;
unsigned int calibration_source;
@ -615,32 +614,20 @@ static int cb_pcidas_caldac_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->caldac_value[chan] != val) {
if (s->readback[chan] != val) {
caldac_8800_write(dev, chan, val);
devpriv->caldac_value[chan] = val;
s->readback[chan] = val;
}
}
return insn->n;
}
static int caldac_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->caldac_value[CR_CHAN(insn->chanspec)];
return 1;
}
/* 1602/16 pregain offset */
static void dac08_write(struct comedi_device *dev, unsigned int value)
{
@ -1514,11 +1501,15 @@ static int cb_pcidas_auto_attach(struct comedi_device *dev,
s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_INTERNAL;
s->n_chan = NUM_CHANNELS_8800;
s->maxdata = 0xff;
s->insn_read = caldac_read_insn;
s->insn_write = cb_pcidas_caldac_insn_write;
ret = comedi_alloc_subdev_readback(s);
if (ret)
return ret;
for (i = 0; i < s->n_chan; i++) {
caldac_8800_write(dev, i, s->maxdata / 2);
devpriv->caldac_value[i] = s->maxdata / 2;
s->readback[i] = s->maxdata / 2;
}
/* trim potentiometer */