diff options
| -rw-r--r-- | drivers/staging/comedi/drivers/cb_pcidas64.c | 30 |
1 files changed, 18 insertions, 12 deletions
diff --git a/drivers/staging/comedi/drivers/cb_pcidas64.c b/drivers/staging/comedi/drivers/cb_pcidas64.c index c641778f3464..17c98a59b44f 100644 --- a/drivers/staging/comedi/drivers/cb_pcidas64.c +++ b/drivers/staging/comedi/drivers/cb_pcidas64.c @@ -3563,21 +3563,27 @@ static void caldac_write(struct comedi_device *dev, unsigned int channel, } } -static int calib_write_insn(struct comedi_device *dev, - struct comedi_subdevice *s, - struct comedi_insn *insn, unsigned int *data) +static int cb_pcidas64_calib_insn_write(struct comedi_device *dev, + struct comedi_subdevice *s, + struct comedi_insn *insn, + unsigned int *data) { - int channel = CR_CHAN(insn->chanspec); + unsigned int chan = CR_CHAN(insn->chanspec); - /* return immediately if setting hasn't changed, since - * programming these things is slow */ - if (s->readback[channel] == data[0]) - return 1; + /* + * Programming the calib device is slow. Only write the + * last data value if the value has changed. + */ + if (insn->n) { + unsigned int val = data[insn->n - 1]; - caldac_write(dev, channel, data[0]); - s->readback[channel] = data[0]; + if (s->readback[chan] != val) { + caldac_write(dev, chan, val); + s->readback[chan] = val; + } + } - return 1; + return insn->n; } static void ad8402_write(struct comedi_device *dev, unsigned int channel, @@ -3848,7 +3854,7 @@ static int setup_subdevices(struct comedi_device *dev) s->maxdata = 0xfff; else s->maxdata = 0xff; - s->insn_write = calib_write_insn; + s->insn_write = cb_pcidas64_calib_insn_write; ret = comedi_alloc_subdev_readback(s); if (ret) |