staging: comedi: me_daq: use comedi_timeout()

Use comedi_timeout() to wait for the analog input end-of-conversion.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/me_daq.c

@@ -248,6 +248,20 @@ static int me_dio_insn_bits(struct comedi_device *dev,
 	return insn->n;
 }
 
+static int me_ai_eoc(struct comedi_device *dev,
+		     struct comedi_subdevice *s,
+		     struct comedi_insn *insn,
+		     unsigned long context)
+{
+	struct me_private_data *dev_private = dev->private;
+	unsigned int status;
+
+	status = readw(dev_private->me_regbase + ME_STATUS);
+	if ((status & 0x0004) == 0)
+		return 0;
+	return -EBUSY;
+}
+
 static int me_ai_insn_read(struct comedi_device *dev,
 			   struct comedi_subdevice *s,
 			   struct comedi_insn *insn,
@@ -258,7 +272,7 @@ static int me_ai_insn_read(struct comedi_device *dev,
 	unsigned int rang = CR_RANGE(insn->chanspec);
 	unsigned int aref = CR_AREF(insn->chanspec);
 	unsigned short val;
-	int i;
+	int ret;
 
 	/* stop any running conversion */
 	dev_private->control_1 &= 0xFFFC;
@@ -290,20 +304,17 @@ static int me_ai_insn_read(struct comedi_device *dev,
 	readw(dev_private->me_regbase + ME_ADC_START);
 
 	/* wait for ADC fifo not empty flag */
-	for (i = 100000; i > 0; i--)
-		if (!(readw(dev_private->me_regbase + ME_STATUS) & 0x0004))
-			break;
-
-	/* get value from ADC fifo */
-	if (i) {
-		val = readw(dev_private->me_regbase + ME_READ_AD_FIFO);
-		val = (val ^ 0x800) & 0x0fff;
-		data[0] = val;
-	} else {
+	ret = comedi_timeout(dev, s, insn, me_ai_eoc, 0);
+	if (ret) {
 		dev_err(dev->class_dev, "Cannot get single value\n");
-		return -EIO;
+		return ret;
 	}
 
+	/* get value from ADC fifo */
+	val = readw(dev_private->me_regbase + ME_READ_AD_FIFO);
+	val = (val ^ 0x800) & 0x0fff;
+	data[0] = val;
+
 	/* stop any running conversion */
 	dev_private->control_1 &= 0xFFFC;
 	writew(dev_private->control_1, dev_private->me_regbase + ME_CONTROL_1);