staging: comedi: adq12b: tidy up adq12b_ai_rinsn()

For aesthetics, rename this function.

Clean up the local variables by reusing 'val' instead of using
separate variables for the:
  'status' - use once to trigger the first A/D conversion
  'hi' and 'lo' - used to read the A/D conversion result

For aesthetics, change the final return to insn->n and remove the
comment.

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>

diff --git a/drivers/staging/comedi/drivers/adq12b.c b/drivers/staging/comedi/drivers/adq12b.c
index e5b236d..4a0bbd7 100644 (file)
--- a/drivers/staging/comedi/drivers/adq12b.c
+++ b/drivers/staging/comedi/drivers/adq12b.c
@@ -132,18 +132,17 @@ static int adq12b_ai_eoc(struct comedi_device *dev,
        return -EBUSY;
 }
 
-static int adq12b_ai_rinsn(struct comedi_device *dev,
-                          struct comedi_subdevice *s,
-                          struct comedi_insn *insn,
-                          unsigned int *data)
+static int adq12b_ai_insn_read(struct comedi_device *dev,
+                              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;
-       unsigned char hi, lo, status;
        int ret;
+       int i;
 
        /* change channel and range only if it is different from the previous */
        val = (range << 4) | chan;
@@ -153,27 +152,20 @@ static int adq12b_ai_rinsn(struct comedi_device *dev,
                udelay(50);     /* wait for the mux to settle */
        }
 
-       /* trigger conversion */
-       status = inb(dev->iobase + ADQ12B_ADLOW);
+       val = inb(dev->iobase + ADQ12B_ADLOW);  /* trigger A/D */
 
-       /* convert n samples */
-       for (n = 0; n < insn->n; n++) {
-
-               /* wait for end of conversion */
+       for (i = 0; i < insn->n; i++) {
                ret = comedi_timeout(dev, s, insn, adq12b_ai_eoc, 0);
                if (ret)
                        return ret;
 
-               /* read data */
-               hi = inb(dev->iobase + ADQ12B_ADHIG);
-               lo = inb(dev->iobase + ADQ12B_ADLOW);
-
-               data[n] = (hi << 8) | lo;
+               val = inb(dev->iobase + ADQ12B_ADHIG) << 8;
+               val |= inb(dev->iobase + ADQ12B_ADLOW); /* retriggers A/D */
 
+               data[i] = val;
        }
 
-       /* return the number of samples read/written */
-       return n;
+       return insn->n;
 }
 
 static int adq12b_di_insn_bits(struct comedi_device *dev,
@@ -254,7 +246,7 @@ static int adq12b_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 
        s->len_chanlist = 4;    /* This is the maximum chanlist length that
                                   the board can handle */
-       s->insn_read = adq12b_ai_rinsn;
+       s->insn_read = adq12b_ai_insn_read;
 
        s = &dev->subdevices[1];
        /* digital input subdevice */