[PATCH 6/8] staging: comedi: fl512: tidy up fl512_ao_insn_write()
H Hartley Sweeten
hsweeten at visionengravers.com
Thu Mar 13 17:09:59 UTC 2014
From: H Hartley Sweeten <hartleys at visionengravers.com>
Tidy up this function. Only save the last value written for readback.
Signed-off-by: H Hartley Sweeten <hsweeten at visionengravers.com>
Cc: Ian Abbott <abbotti at mev.co.uk>
Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
drivers/staging/comedi/drivers/fl512.c | 25 +++++++++++++------------
1 file changed, 13 insertions(+), 12 deletions(-)
diff --git a/drivers/staging/comedi/drivers/fl512.c b/drivers/staging/comedi/drivers/fl512.c
index 8cb1f1e..90a8fd9 100644
--- a/drivers/staging/comedi/drivers/fl512.c
+++ b/drivers/staging/comedi/drivers/fl512.c
@@ -76,20 +76,21 @@ static int fl512_ao_insn_write(struct comedi_device *dev,
unsigned int *data)
{
struct fl512_private *devpriv = dev->private;
- int n;
- int chan = CR_CHAN(insn->chanspec); /* get chan to write */
-
- for (n = 0; n < insn->n; n++) { /* write n data set */
- /* write low byte */
- outb(data[n] & 0x0ff, dev->iobase + FL512_AO_DATA_REG(chan));
- /* write high byte */
- outb((data[n] & 0xf00) >> 8,
- dev->iobase + FL512_AO_DATA_REG(chan));
- inb(dev->iobase + FL512_AO_TRIG_REG(chan));
+ unsigned int chan = CR_CHAN(insn->chanspec);
+ unsigned int val = devpriv->ao_readback[chan];
+ int i;
+
+ for (i = 0; i < insn->n; i++) {
+ val = data[i];
- devpriv->ao_readback[chan] = data[n];
+ /* write LSB, MSB then trigger conversion */
+ outb(val & 0x0ff, dev->iobase + FL512_AO_DATA_REG(chan));
+ outb((val >> 8) & 0xf, dev->iobase + FL512_AO_DATA_REG(chan));
+ inb(dev->iobase + FL512_AO_TRIG_REG(chan));
}
- return n;
+ devpriv->ao_readback[chan] = val;
+
+ return insn->n;
}
static int fl512_ao_insn_read(struct comedi_device *dev,
--
1.8.5.2
More information about the devel
mailing list