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@xxxxxxxxxxxxxxxxxxx>
Cc: Ian Abbott <abbotti@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/staging/comedi/drivers/cb_pcidas64.c | 33 ++++++++++------------------
1 file changed, 11 insertions(+), 22 deletions(-)
diff --git a/drivers/staging/comedi/drivers/cb_pcidas64.c b/drivers/staging/comedi/drivers/cb_pcidas64.c
index 17c98a5..d80f34d 100644
--- a/drivers/staging/comedi/drivers/cb_pcidas64.c
+++ b/drivers/staging/comedi/drivers/cb_pcidas64.c
@@ -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;
--
2.0.3
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