staging: comedi: fl512: tidy up fl512_ao_insn_read()

Tidy up this function.

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/fl512.c b/drivers/staging/comedi/drivers/fl512.c
index 90a8fd9..3bf6d6f 100644 (file)
--- a/drivers/staging/comedi/drivers/fl512.c
+++ b/drivers/staging/comedi/drivers/fl512.c
@@ -52,22 +52,26 @@ static int fl512_ai_insn_read(struct comedi_device *dev,
                              struct comedi_insn *insn,
                              unsigned int *data)
 {
-       int n;
-       unsigned int lo_byte, hi_byte;
-       char chan = CR_CHAN(insn->chanspec);
-
-       for (n = 0; n < insn->n; n++) { /* sample n times on selected channel */
-               /* XXX probably can move next step out of for() loop -- will
-                * make AI a little bit faster. */
-               outb(chan, dev->iobase + FL512_AI_MUX_REG);
+       unsigned int chan = CR_CHAN(insn->chanspec);
+       unsigned int val;
+       int i;
+
+       outb(chan, dev->iobase + FL512_AI_MUX_REG);
+
+       for (i = 0; i < insn->n; i++) {
                outb(0, dev->iobase + FL512_AI_START_CONV_REG);
+
                /* XXX should test "done" flag instead of delay */
-               udelay(30);     /* sleep 30 usec */
-               lo_byte = inb(dev->iobase + FL512_AI_LSB_REG);
-               hi_byte = inb(dev->iobase + FL512_AI_MSB_REG) & 0xf;
-               data[n] = lo_byte + (hi_byte << 8);
+               udelay(30);
+
+               val = inb(dev->iobase + FL512_AI_LSB_REG);
+               val |= (inb(dev->iobase + FL512_AI_MSB_REG) << 8);
+               val &= s->maxdata;
+
+               data[i] = val;
        }
-       return n;
+
+       return insn->n;
 }
 
 static int fl512_ao_insn_write(struct comedi_device *dev,