staging: comedi: comedi_test: use comedi_fc helpers to validate timer args

Use the comedi_fc helper cfc_check_trigger_arg_is() to validate the
trigger arguments when the source is TRIG_TIMER.

All the arguments are unsigned int, change the local variable to an
unsigned int and rename it for aesthetic reasons.
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>

drivers/staging/comedi/drivers/comedi_test.c

@@ -226,7 +226,7 @@ static int waveform_ai_cmdtest(struct comedi_device *dev,
 			       struct comedi_cmd *cmd)
 {
 	int err = 0;
-	int tmp;
+	unsigned int arg;
 
 	/* Step 1 : check if triggers are trivially valid */
 
@@ -278,22 +278,18 @@ static int waveform_ai_cmdtest(struct comedi_device *dev,
 	/* step 4: fix up any arguments */
 
 	if (cmd->scan_begin_src == TRIG_TIMER) {
-		tmp = cmd->scan_begin_arg;
+		arg = cmd->scan_begin_arg;
 		/* round to nearest microsec */
-		cmd->scan_begin_arg =
-		    nano_per_micro * ((tmp +
-				       (nano_per_micro / 2)) / nano_per_micro);
-		if (tmp != cmd->scan_begin_arg)
-			err++;
+		arg = nano_per_micro *
+		      ((arg + (nano_per_micro / 2)) / nano_per_micro);
+		err |= cfc_check_trigger_arg_is(&cmd->scan_begin_arg, arg);
 	}
 	if (cmd->convert_src == TRIG_TIMER) {
-		tmp = cmd->convert_arg;
+		arg = cmd->convert_arg;
 		/* round to nearest microsec */
-		cmd->convert_arg =
-		    nano_per_micro * ((tmp +
-				       (nano_per_micro / 2)) / nano_per_micro);
-		if (tmp != cmd->convert_arg)
-			err++;
+		arg = nano_per_micro *
+		      ((arg + (nano_per_micro / 2)) / nano_per_micro);
+		err |= cfc_check_trigger_arg_is(&cmd->convert_arg, arg);
 	}
 
 	if (err)