For aesthetics, move this function out of the async command support
code.
For safety, the INT request (end-of-conversion flag) should be cleared
before doing each conversion and after the final data sample is read.
This driver already clears the flag before starting a conversion but it
does not clear the flag after the final sample.
Refactor the function a bit so that the flag is cleared for a conversion
timeout and after the last sample.
Do a bit of other tidying up during the move.
Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Ian Abbott <abbotti@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/staging/comedi/drivers/pcl818.c | 73 ++++++++++++++++-----------------
1 file changed, 36 insertions(+), 37 deletions(-)
diff --git a/drivers/staging/comedi/drivers/pcl818.c b/drivers/staging/comedi/drivers/pcl818.c
index 4918da3..5eea4eb 100644
--- a/drivers/staging/comedi/drivers/pcl818.c
+++ b/drivers/staging/comedi/drivers/pcl818.c
@@ -443,43 +443,6 @@ static int pcl818_ai_eoc(struct comedi_device *dev,
return -EBUSY;
}
-static int pcl818_ai_insn_read(struct comedi_device *dev,
- struct comedi_subdevice *s,
- struct comedi_insn *insn, unsigned int *data)
-{
- int ret;
- int n;
-
- /* software trigger, DMA and INT off */
- outb(0, dev->iobase + PCL818_CONTROL);
-
- /* select channel */
- outb(muxonechan[CR_CHAN(insn->chanspec)], dev->iobase + PCL818_MUX);
-
- /* select gain */
- outb(CR_RANGE(insn->chanspec), dev->iobase + PCL818_RANGE);
-
- for (n = 0; n < insn->n; n++) {
-
- /* clear INT (conversion end) flag */
- outb(0, dev->iobase + PCL818_CLRINT);
-
- /* start conversion */
- outb(0, dev->iobase + PCL818_AD_LO);
-
- ret = comedi_timeout(dev, s, insn, pcl818_ai_eoc, 0);
- if (ret) {
- /* clear INT (conversion end) flag */
- outb(0, dev->iobase + PCL818_CLRINT);
- return ret;
- }
-
- data[n] = pcl818_ai_get_sample(dev, s, NULL);
- }
-
- return n;
-}
-
static bool pcl818_ai_dropout(struct comedi_device *dev,
struct comedi_subdevice *s,
unsigned int chan)
@@ -963,6 +926,42 @@ static int pcl818_ai_cancel(struct comedi_device *dev,
return 0;
}
+static int pcl818_ai_insn_read(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ struct comedi_insn *insn,
+ unsigned int *data)
+{
+ unsigned int chan = CR_CHAN(insn->chanspec);
+ unsigned int range = CR_RANGE(insn->chanspec);
+ int ret = 0;
+ int i;
+
+ /* software trigger, DMA and INT off */
+ outb(0, dev->iobase + PCL818_CONTROL);
+
+ /* select channel */
+ outb(muxonechan[chan], dev->iobase + PCL818_MUX);
+ /* select gain */
+ outb(range, dev->iobase + PCL818_RANGE);
+
+ for (i = 0; i < insn->n; i++) {
+ /* clear INT (conversion end) flag */
+ outb(0, dev->iobase + PCL818_CLRINT);
+ /* start conversion */
+ outb(0, dev->iobase + PCL818_AD_LO);
+
+ ret = comedi_timeout(dev, s, insn, pcl818_ai_eoc, 0);
+ if (ret)
+ break;
+
+ data[i] = pcl818_ai_get_sample(dev, s, NULL);
+ }
+ /* clear INT (conversion end) flag */
+ outb(0, dev->iobase + PCL818_CLRINT);
+
+ return ret ? ret : insn->n;
+}
+
static int pcl818_ao_insn_write(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn,
--
1.8.5.2
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