staging: comedi: pcl816: introduce pcl816_ai_soft_trig()

Introduce a helper function to start a software triggered analog input
conversion.

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/pcl816.c b/drivers/staging/comedi/drivers/pcl816.c
index 40fd27789886c2105dd2f9eba7da5f93cbdb5af6..f77bc68ba12fceb236779ab8c9bb2204a522e0df 100644 (file)
--- a/drivers/staging/comedi/drivers/pcl816.c
+++ b/drivers/staging/comedi/drivers/pcl816.c
@@ -214,6 +214,12 @@ static void pcl816_ai_clear_eoc(struct comedi_device *dev)
        outb(0, dev->iobase + PCL816_CLRINT);
 }
 
+static void pcl816_ai_soft_trig(struct comedi_device *dev)
+{
+       /* writing any value triggers a software conversion */
+       outb(0, dev->iobase + PCL816_AD_LO);
+}
+
 static unsigned int pcl816_ai_get_sample(struct comedi_device *dev,
                                         struct comedi_subdevice *s)
 {
@@ -508,7 +514,7 @@ static int pcl816_ai_cancel(struct comedi_device *dev,
        i8254_set_mode(dev->iobase + PCL816_TIMER_BASE, 0,
                        1, I8254_MODE0 | I8254_BINARY);
 
-       outb(0, dev->iobase + PCL816_AD_LO);
+       pcl816_ai_soft_trig(dev);
        pcl816_ai_get_sample(dev, s);
 
        pcl816_ai_clear_eoc(dev);
@@ -619,8 +625,7 @@ static int pcl816_ai_insn_read(struct comedi_device *dev,
 
        for (i = 0; i < insn->n; i++) {
                pcl816_ai_clear_eoc(dev);
-               /* start conversion */
-               outb(0, dev->iobase + PCL816_AD_LO);
+               pcl816_ai_soft_trig(dev);
 
                ret = comedi_timeout(dev, s, insn, pcl816_ai_eoc, 0);
                if (ret)