staging: comedi: pcl711: put acquired data in buffer for AI command

The asynchronous command support for the AI subdevice is still missing
one crucial element, it doesn't actually put the acquired data in the
buffer so it can be read()!  Call `comedi_buf_put()` from the interrupt
handler to perform this function.  A return value of 0 from
`comedi_buf_put()` means there was no room in the buffer so set the
`COMEDI_CB_OVERFLOW` and `COMEDI_CB_ERROR` event flags in that case.
Otherwise, set the `COMEDI_CB_BLOCK` and `COMEDI_CB_EOS` event flags to
mark the end of a "scan" (the scan length is currently fixed at one
sample in this driver).

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers/pcl711.c b/drivers/staging/comedi/drivers/pcl711.c
index daa78fa63be1a53bacf921fbc8585bf9d28d126c..e170f8aeef5faa377a6c731f03e01e8788a00659 100644 (file)
--- a/drivers/staging/comedi/drivers/pcl711.c
+++ b/drivers/staging/comedi/drivers/pcl711.c
@@ -213,9 +213,15 @@ static irqreturn_t pcl711_interrupt(int irq, void *d)
 
        outb(PCL711_INT_STAT_CLR, dev->iobase + PCL711_INT_STAT_REG);
 
-       if (s->async->cmd.stop_src == TRIG_COUNT && !(--devpriv->ntrig)) {
-               pcl711_ai_set_mode(dev, PCL711_MODE_SOFTTRIG);
-               s->async->events |= COMEDI_CB_EOA;
+       if (comedi_buf_put(s->async, (short)data) == 0) {
+               s->async->events |= COMEDI_CB_OVERFLOW | COMEDI_CB_ERROR;
+       } else {
+               s->async->events |= COMEDI_CB_BLOCK | COMEDI_CB_EOS;
+               if (s->async->cmd.stop_src == TRIG_COUNT &&
+                   !(--devpriv->ntrig)) {
+                       pcl711_ai_set_mode(dev, PCL711_MODE_SOFTTRIG);
+                       s->async->events |= COMEDI_CB_EOA;
+               }
        }
        comedi_event(dev, s);
        return IRQ_HANDLED;