V4L/DVB: Fix unlock logic at medusa_video_init

As reported by Dan Carpenter:
> This was my patch:  "cx25821: fix double unlock in medusa_video_init()"
>
> It accidentally got merged two times.  The version from the staging tree
> is not correct.  Please can you revert it:
> 7a02f549fcc30fe6be0c0024beae9a3db22e1af6 "Staging: cx25821: fix double
> unlock in medusa_video_init()"

After reviewing the logic at the function, instead of just adding a patch to
revert the wrong one, the better is to apply a different logic: add a goto
that will always unlock and return the error.

This simplifies the code a little bit, and, instead of just return -EINVAL,
it will return the error condition reported by the called functions.

This patch is folded with another patch from Dan that added one missing
goto.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/staging/cx25821/cx25821-medusa-video.c

@@ -778,9 +778,9 @@ int medusa_set_saturation(struct cx25821_dev *dev, int saturation, int decoder)
 
 int medusa_video_init(struct cx25821_dev *dev)
 {
-	u32 value = 0, tmp = 0;
-	int ret_val = 0;
-	int i = 0;
+	u32 value, tmp = 0;
+	int ret_val;
+	int i;
 
 	mutex_lock(&dev->lock);
 
@@ -790,18 +790,15 @@ int medusa_video_init(struct cx25821_dev *dev)
 	value = cx25821_i2c_read(&dev->i2c_bus[0], MON_A_CTRL, &tmp);
 	value &= 0xFFFFF0FF;
 	ret_val = cx25821_i2c_write(&dev->i2c_bus[0], MON_A_CTRL, value);
+	if (ret_val < 0)
+		goto error;
 
-	if (ret_val < 0) {
-		mutex_unlock(&dev->lock);
-		return -EINVAL;
-	}
 	/* Turn off Master source switch enable */
 	value = cx25821_i2c_read(&dev->i2c_bus[0], MON_A_CTRL, &tmp);
 	value &= 0xFFFFFFDF;
 	ret_val = cx25821_i2c_write(&dev->i2c_bus[0], MON_A_CTRL, value);
-
 	if (ret_val < 0)
-		return -EINVAL;
+		goto error;
 
 	mutex_unlock(&dev->lock);
 
@@ -815,31 +812,25 @@ int medusa_video_init(struct cx25821_dev *dev)
 	value &= 0xFF70FF70;
 	value |= 0x00090008;	/* set en_active */
 	ret_val = cx25821_i2c_write(&dev->i2c_bus[0], DENC_AB_CTRL, value);
+	if (ret_val < 0)
+		goto error;
 
-	if (ret_val < 0) {
-		mutex_unlock(&dev->lock);
-		return -EINVAL;
-	}
 	/* enable input is VIP/656 */
 	value = cx25821_i2c_read(&dev->i2c_bus[0], BYP_AB_CTRL, &tmp);
 	value |= 0x00040100;	/* enable VIP */
 	ret_val = cx25821_i2c_write(&dev->i2c_bus[0], BYP_AB_CTRL, value);
 
-	if (ret_val < 0) {
-		mutex_unlock(&dev->lock);
-		return -EINVAL;
-	}
+	if (ret_val < 0)
+		goto error;
+
 	/* select AFE clock to output mode */
 	value = cx25821_i2c_read(&dev->i2c_bus[0], AFE_AB_DIAG_CTRL, &tmp);
 	value &= 0x83FFFFFF;
-	ret_val =
-	    cx25821_i2c_write(&dev->i2c_bus[0], AFE_AB_DIAG_CTRL,
-			      value | 0x10000000);
+	ret_val = cx25821_i2c_write(&dev->i2c_bus[0], AFE_AB_DIAG_CTRL,
+				    value | 0x10000000);
+	if (ret_val < 0)
+		goto error;
 
-	if (ret_val < 0) {
-		mutex_unlock(&dev->lock);
-		return -EINVAL;
-	}
 	/* Turn on all of the data out and control output pins. */
 	value = cx25821_i2c_read(&dev->i2c_bus[0], PIN_OE_CTRL, &tmp);
 	value &= 0xFEF0FE00;
@@ -858,17 +849,15 @@ int medusa_video_init(struct cx25821_dev *dev)
 
 	value |= 7;
 	ret_val = cx25821_i2c_write(&dev->i2c_bus[0], PIN_OE_CTRL, value);
-	if (ret_val < 0) {
-		mutex_unlock(&dev->lock);
-		return -EINVAL;
-	}
+	if (ret_val < 0)
+		goto error;
 
 	mutex_unlock(&dev->lock);
 
 	ret_val = medusa_set_videostandard(dev);
+	return ret_val;
 
-	if (ret_val < 0)
-		return -EINVAL;
-
-	return 1;
+error:
+	mutex_unlock(&dev->lock);
+	return ret_val;
 }