staging: comedi: me4000: Check for unsupported INSN_CONFIG.

The INSN_CONFIG handler for the DIO subdevice should error out for
unsupported configuration instruction codes.

Also fix incorrect use of constant COMEDI_OUTPUT where
INSN_CONFIG_DIO_OUTPUT was meant.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers/me4000.c b/drivers/staging/comedi/drivers/me4000.c
index b692fea..b0bc6bb 100644 (file)
--- a/drivers/staging/comedi/drivers/me4000.c
+++ b/drivers/staging/comedi/drivers/me4000.c
@@ -2098,23 +2098,29 @@ static int me4000_dio_insn_config(struct comedi_device *dev,
 
        CALL_PDEBUG("In me4000_dio_insn_config()\n");
 
-       if (data[0] == INSN_CONFIG_DIO_QUERY) {
+       switch (data[0]) {
+       default:
+               return -EINVAL;
+       case INSN_CONFIG_DIO_QUERY:
                data[1] =
                    (s->io_bits & (1 << chan)) ? COMEDI_OUTPUT : COMEDI_INPUT;
                return insn->n;
+       case INSN_CONFIG_DIO_INPUT:
+       case INSN_CONFIG_DIO_OUTPUT:
+               break;
        }
 
        /*
         * The input or output configuration of each digital line is
         * configured by a special insn_config instruction.  chanspec
         * contains the channel to be changed, and data[0] contains the
-        * value COMEDI_INPUT or COMEDI_OUTPUT.
+        * value INSN_CONFIG_DIO_INPUT or INSN_CONFIG_DIO_OUTPUT.
         * On the ME-4000 it is only possible to switch port wise (8 bit)
         */
 
        tmp = me4000_inl(dev, info->dio_context.ctrl_reg);
 
-       if (data[0] == COMEDI_OUTPUT) {
+       if (data[0] == INSN_CONFIG_DIO_OUTPUT) {
                if (chan < 8) {
                        s->io_bits |= 0xFF;
                        tmp &= ~(ME4000_DIO_CTRL_BIT_MODE_0 |