staging: comedi: ni_labpc_common: use comedi_timeout() when writing to eeprom

Use the comedi_timeout() helper to wait for the eeprom to be ready to accept
writes and remove the timeout loop in labpc_eeprom_write().

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>

1 files changed, 18 insertions, 19 deletions

diff --git a/drivers/staging/comedi/drivers/ni_labpc_common.c b/drivers/staging/comedi/drivers/ni_labpc_common.c
index 9d26aced..d89d585 100644
--- a/drivers/staging/comedi/drivers/ni_labpc_common.c
+++ b/drivers/staging/comedi/drivers/ni_labpc_common.c
@@ -1078,27 +1078,13 @@ static unsigned int labpc_eeprom_read_status(struct comedi_device *dev)
 	return value;
 }
 
-static int labpc_eeprom_write(struct comedi_device *dev,
-			      unsigned int address, unsigned int value)
+static void labpc_eeprom_write(struct comedi_device *dev,
+			       unsigned int address, unsigned int value)
 {
 	struct labpc_private *devpriv = dev->private;
 	const int write_enable_instruction = 0x6;
 	const int write_instruction = 0x2;
 	const int write_length = 8;	/*  8 bit write lengths to eeprom */
-	const int write_in_progress_bit = 0x1;
-	const int timeout = 10000;
-	int i;
-
-	/*  make sure there isn't already a write in progress */
-	for (i = 0; i < timeout; i++) {
-		if ((labpc_eeprom_read_status(dev) & write_in_progress_bit) ==
-		    0)
-			break;
-	}
-	if (i == timeout) {
-		dev_err(dev->class_dev, "eeprom write timed out\n");
-		return -ETIME;
-	}
 
 	/*  enable read/write to eeprom */
 	devpriv->cmd5 &= ~CMD5_EEPROMCS;
@@ -1131,8 +1117,6 @@ static int labpc_eeprom_write(struct comedi_device *dev,
 	devpriv->cmd5 &= ~(CMD5_EEPROMCS | CMD5_WRTPRT);
 	udelay(1);
 	devpriv->write_byte(dev, devpriv->cmd5, CMD5_REG);
-
-	return 0;
 }
 
 /* writes to 8 bit calibration dacs */
@@ -1183,6 +1167,20 @@ static int labpc_calib_insn_write(struct comedi_device *dev,
 	return insn->n;
 }
 
+static int labpc_eeprom_ready(struct comedi_device *dev,
+			      struct comedi_subdevice *s,
+			      struct comedi_insn *insn,
+			      unsigned long context)
+{
+	unsigned int status;
+
+	/* make sure there isn't already a write in progress */
+	status = labpc_eeprom_read_status(dev);
+	if ((status & 0x1) == 0)
+		return 0;
+	return -EBUSY;
+}
+
 static int labpc_eeprom_insn_write(struct comedi_device *dev,
 				   struct comedi_subdevice *s,
 				   struct comedi_insn *insn,
@@ -1202,10 +1200,11 @@ static int labpc_eeprom_insn_write(struct comedi_device *dev,
 	if (insn->n > 0) {
 		unsigned int val = data[insn->n - 1];
 
-		ret = labpc_eeprom_write(dev, chan, val);
+		ret = comedi_timeout(dev, s, insn, labpc_eeprom_ready, 0);
 		if (ret)
 			return ret;
 
+		labpc_eeprom_write(dev, chan, val);
 		s->readback[chan] = val;
 	}