staging: comedi: usbduxfast: only chanlist of 1, 2, 3, or 16 are supported

The analog input (*do_cmd) only supports channel lists of 1, 2, 3, or 16
channels. Add a check for this to usbduxfast_ai_check_chanlist() and remove
the check from usbduxfast_ai_cmd().

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/usbduxfast.c b/drivers/staging/comedi/drivers/usbduxfast.c
index 16b28faa2ec2d29c499ca632ab1c0e06f330e84f..a8635b1659a4b09497eb5bb81b06d0421176c525 100644 (file)
--- a/drivers/staging/comedi/drivers/usbduxfast.c
+++ b/drivers/staging/comedi/drivers/usbduxfast.c
@@ -339,6 +339,11 @@ static int usbduxfast_ai_check_chanlist(struct comedi_device *dev,
        unsigned int gain0 = CR_RANGE(cmd->chanlist[0]);
        int i;
 
+       if (cmd->chanlist_len > 3 && cmd->chanlist_len != 16) {
+               dev_err(dev->class_dev, "unsupported combination of channels\n");
+               return -EINVAL;
+       }
+
        for (i = 0; i < cmd->chanlist_len; ++i) {
                unsigned int chan = CR_CHAN(cmd->chanlist[i]);
                unsigned int gain = CR_RANGE(cmd->chanlist[i]);
@@ -779,11 +784,6 @@ static int usbduxfast_ai_cmd(struct comedi_device *dev,
                usbduxfast_cmd_data(dev, 4, 0x09, 0x01, rngmask, 0xff);
 
                break;
-
-       default:
-               dev_err(dev->class_dev, "unsupported combination of channels\n");
-               up(&devpriv->sem);
-               return -EFAULT;
        }
 
        /* 0 means that the AD commands are sent */