staging: comedi: cb_pcidas64: use subdevice readback for 'ad8402_state'

Use the comedi_subdevice 'readback' member and the core provided (*insn_read)
to handle the readback of the write-only calibration subdevice. Remove the
then unused 'ad8402_state' 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 15:07:21 -07:00 committed by Greg Kroah-Hartman
parent 5e2de5e7f9
commit fe1184e49a

View file

@ -1105,8 +1105,6 @@ struct pcidas64_private {
uint8_t i2c_cal_range_bits;
/* configure digital triggers to trigger on falling edge */
unsigned int ext_trig_falling;
/* states of various devices stored to enable read-back */
unsigned int ad8402_state[2];
short ai_cmd_running;
unsigned int ai_fifo_segment_length;
struct ext_clock_info ext_clock;
@ -3595,8 +3593,6 @@ static void ad8402_write(struct comedi_device *dev, unsigned int channel,
unsigned int bitstream = ((channel & 0x3) << 8) | (value & 0xff);
static const int ad8402_udelay = 1;
devpriv->ad8402_state[channel] = value;
register_bits = SELECT_8402_64XX_BIT;
udelay(ad8402_udelay);
writew(register_bits, devpriv->main_iobase + CALIBRATION_REG);
@ -3622,33 +3618,20 @@ static int ad8402_write_insn(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn, unsigned int *data)
{
struct pcidas64_private *devpriv = dev->private;
int channel = CR_CHAN(insn->chanspec);
/* return immediately if setting hasn't changed, since
* programming these things is slow */
if (devpriv->ad8402_state[channel] == data[0])
if (s->readback[channel] == data[0])
return 1;
devpriv->ad8402_state[channel] = data[0];
s->readback[channel] = data[0];
ad8402_write(dev, channel, data[0]);
return 1;
}
static int ad8402_read_insn(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn, unsigned int *data)
{
struct pcidas64_private *devpriv = dev->private;
unsigned int channel = CR_CHAN(insn->chanspec);
data[0] = devpriv->ad8402_state[channel];
return 1;
}
static uint16_t read_eeprom(struct comedi_device *dev, uint8_t address)
{
struct pcidas64_private *devpriv = dev->private;
@ -3871,11 +3854,17 @@ static int setup_subdevices(struct comedi_device *dev)
s->type = COMEDI_SUBD_CALIB;
s->subdev_flags = SDF_READABLE | SDF_WRITABLE | SDF_INTERNAL;
s->n_chan = 2;
s->insn_read = ad8402_read_insn;
s->insn_write = ad8402_write_insn;
s->maxdata = 0xff;
for (i = 0; i < s->n_chan; i++)
s->insn_write = ad8402_write_insn;
ret = comedi_alloc_subdev_readback(s);
if (ret)
return ret;
for (i = 0; i < s->n_chan; i++) {
ad8402_write(dev, i, s->maxdata / 2);
s->readback[i] = s->maxdata / 2;
}
} else
s->type = COMEDI_SUBD_UNUSED;