staging: comedi: adv_pci1710: fix ai (*insn_read)

An (*insn_read) can only happen if the subdevice is in a non-busy state,
i.e. an async command is not running. The board reset and subdevice
(*cancel) will ensure that the control bits (devpriv->ctrl) are already
cleared.

The (*insn_read) only needs to enable the software trigger before reading
samples. It should also disable the software trigger when done. Fix the
(*insn_read) to do this.

For aesthetics, rename the function so it has namespace associated with
the driver.

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/adv_pci1710.c b/drivers/staging/comedi/drivers/adv_pci1710.c
index 5f1e86e767c80886795127395f10b744484af8a8..93b3e3fedbb6d65413d17dd7b4a7b807d08667bd 100644 (file)
--- a/drivers/staging/comedi/drivers/adv_pci1710.c
+++ b/drivers/staging/comedi/drivers/adv_pci1710.c
@@ -325,7 +325,7 @@ static int pci171x_ai_read_sample(struct comedi_device *dev,
        return 0;
 }
 
-static int pci171x_ai_insn_read(struct comedi_device *dev,
+static int pci1710_ai_insn_read(struct comedi_device *dev,
                                struct comedi_subdevice *s,
                                struct comedi_insn *insn,
                                unsigned int *data)
@@ -334,9 +334,10 @@ static int pci171x_ai_insn_read(struct comedi_device *dev,
        int ret = 0;
        int i;
 
-       devpriv->ctrl &= PCI171X_CTRL_CNT0;
-       devpriv->ctrl |= PCI171X_CTRL_SW;       /*  set software trigger */
+       /* enable software trigger */
+       devpriv->ctrl |= PCI171X_CTRL_SW;
        outw(devpriv->ctrl, dev->iobase + PCI171X_CTRL_REG);
+
        outb(0, dev->iobase + PCI171X_CLRFIFO_REG);
        outb(0, dev->iobase + PCI171X_CLRINT_REG);
 
@@ -359,6 +360,10 @@ static int pci171x_ai_insn_read(struct comedi_device *dev,
                data[i] = val;
        }
 
+       /* disable software trigger */
+       devpriv->ctrl &= ~PCI171X_CTRL_SW;
+       outw(devpriv->ctrl, dev->iobase + PCI171X_CTRL_REG);
+
        outb(0, dev->iobase + PCI171X_CLRFIFO_REG);
        outb(0, dev->iobase + PCI171X_CLRINT_REG);
 
@@ -802,7 +807,7 @@ static int pci1710_auto_attach(struct comedi_device *dev,
        s->n_chan       = board->is_pci1713 ? 32 : 16;
        s->maxdata      = 0x0fff;
        s->range_table  = board->ai_range;
-       s->insn_read    = pci171x_ai_insn_read;
+       s->insn_read    = pci1710_ai_insn_read;
        if (dev->irq) {
                dev->read_subdev = s;
                s->subdev_flags |= SDF_CMD_READ;