staging: comedi: s626: use comedi_timeout() on remaining loops

There were just a handful of more while loops in this file that needed
timeouts, and this patch takes care of them.  One new callback is
introduced, and all of the proper comedi_timeout() calls are then used.
The return type of s626_i2c_handshake() has been changed from uint32_t to
int so that a negative error code from comedi_timeout() can be propagated
if necessary.
Signed-off-by: Chase Southwood <chase.southwood@yahoo.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/s626.c

@@ -295,10 +295,24 @@ static void s626_debi_replace(struct comedi_device *dev, unsigned int addr,
 
 /* **************  EEPROM ACCESS FUNCTIONS  ************** */
 
-static uint32_t s626_i2c_handshake(struct comedi_device *dev, uint32_t val)
+static int s626_i2c_handshake_eoc(struct comedi_device *dev,
+				 struct comedi_subdevice *s,
+				 struct comedi_insn *insn,
+				 unsigned long context)
+{
+	bool status;
+
+	status = s626_mc_test(dev, S626_MC2_UPLD_IIC, S626_P_MC2);
+	if (status)
+		return 0;
+	return -EBUSY;
+}
+
+static int s626_i2c_handshake(struct comedi_device *dev, uint32_t val)
 {
 	struct s626_private *devpriv = dev->private;
 	unsigned int ctrl;
+	int ret;
 
 	/* Write I2C command to I2C Transfer Control shadow register */
 	writel(val, devpriv->mmio + S626_P_I2CCTRL);
@@ -308,8 +322,9 @@ static uint32_t s626_i2c_handshake(struct comedi_device *dev, uint32_t val)
 	 * wait for upload confirmation.
 	 */
 	s626_mc_enable(dev, S626_MC2_UPLD_IIC, S626_P_MC2);
-	while (!s626_mc_test(dev, S626_MC2_UPLD_IIC, S626_P_MC2))
-		;
+	ret = comedi_timeout(dev, NULL, NULL, s626_i2c_handshake_eoc, 0);
+	if (ret)
+		return ret;
 
 	/* Wait until I2C bus transfer is finished or an error occurs */
 	do {
@@ -2029,8 +2044,9 @@ static int s626_ai_insn_read(struct comedi_device *dev,
 	/* Wait for the data to arrive in FB BUFFER 1 register. */
 
 	/* Wait for ADC done */
-	while (!(readl(devpriv->mmio + S626_P_PSR) & S626_PSR_GPIO2))
-		;
+	ret = comedi_timeout(dev, s, insn, s626_ai_eoc, 0);
+	if (ret)
+		return ret;
 
 	/* Fetch ADC data from audio interface's input shift register. */
 
@@ -2681,8 +2697,9 @@ static int s626_initialize(struct comedi_device *dev)
 	writel(S626_I2C_CLKSEL | S626_I2C_ABORT,
 	       devpriv->mmio + S626_P_I2CSTAT);
 	s626_mc_enable(dev, S626_MC2_UPLD_IIC, S626_P_MC2);
-	while (!(readl(devpriv->mmio + S626_P_MC2) & S626_MC2_UPLD_IIC))
-		;
+	ret = comedi_timeout(dev, NULL, NULL, s626_i2c_handshake_eoc, 0);
+	if (ret)
+		return ret;
 
 	/*
 	 * Per SAA7146 data sheet, write to STATUS
@@ -2691,8 +2708,9 @@ static int s626_initialize(struct comedi_device *dev)
 	for (i = 0; i < 2; i++) {
 		writel(S626_I2C_CLKSEL, devpriv->mmio + S626_P_I2CSTAT);
 		s626_mc_enable(dev, S626_MC2_UPLD_IIC, S626_P_MC2);
-		while (!s626_mc_test(dev, S626_MC2_UPLD_IIC, S626_P_MC2))
-			;
+		ret = comedi_timeout(dev, NULL, NULL, s626_i2c_handshake_eoc, 0);
+		if (ret)
+			return ret;
 	}
 
 	/*