diff options
| -rw-r--r-- | drivers/staging/comedi/drivers/adq12b.c | 25 |
1 files changed, 11 insertions, 14 deletions
diff --git a/drivers/staging/comedi/drivers/adq12b.c b/drivers/staging/comedi/drivers/adq12b.c index b4ea377..e5b236d 100644 --- a/drivers/staging/comedi/drivers/adq12b.c +++ b/drivers/staging/comedi/drivers/adq12b.c @@ -116,8 +116,7 @@ static const struct comedi_lrange range_adq12b_ai_unipolar = { struct adq12b_private { int unipolar; /* option 2 of comedi_config (1 is iobase) */ int differential; /* option 3 of comedi_config */ - int last_channel; - int last_range; + unsigned int last_ctreg; }; static int adq12b_ai_eoc(struct comedi_device *dev, @@ -134,20 +133,23 @@ static int adq12b_ai_eoc(struct comedi_device *dev, } static int adq12b_ai_rinsn(struct comedi_device *dev, - struct comedi_subdevice *s, struct comedi_insn *insn, + struct comedi_subdevice *s, + struct comedi_insn *insn, unsigned int *data) { struct adq12b_private *devpriv = dev->private; + unsigned int chan = CR_CHAN(insn->chanspec); + unsigned int range = CR_RANGE(insn->chanspec); + unsigned int val; int n; - int range, channel; unsigned char hi, lo, status; int ret; /* change channel and range only if it is different from the previous */ - range = CR_RANGE(insn->chanspec); - channel = CR_CHAN(insn->chanspec); - if (channel != devpriv->last_channel || range != devpriv->last_range) { - outb((range << 4) | channel, dev->iobase + ADQ12B_CTREG); + val = (range << 4) | chan; + if (val != devpriv->last_ctreg) { + outb(val, dev->iobase + ADQ12B_CTREG); + devpriv->last_ctreg = val; udelay(50); /* wait for the mux to settle */ } @@ -226,12 +228,7 @@ static int adq12b_attach(struct comedi_device *dev, struct comedi_devconfig *it) devpriv->unipolar = it->options[1]; devpriv->differential = it->options[2]; - /* - * initialize channel and range to -1 so we make sure we - * always write at least once to the CTREG in the instruction - */ - devpriv->last_channel = -1; - devpriv->last_range = -1; + devpriv->last_ctreg = -1; /* force ctreg update */ ret = comedi_alloc_subdevices(dev, 3); if (ret) |