From: Matt Ranostay <mranostay@gmail.com>
Date: Mon, 30 May 2016 02:52:02 +0000 (-0700)
Subject: iio: hudmidity: hdc100x: fix incorrect shifting and scaling
X-Git-Tag: firefly_0821_release~176^2~4^2~37^2~42
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=784108d9df5aea1d58d2a56900efaa8149507964;p=firefly-linux-kernel-4.4.55.git

iio: hudmidity: hdc100x: fix incorrect shifting and scaling

commit 94bef000f1d4aa111f4ddda1482cf3b30ad069ce upstream.

Shifting sensor data to the right 2 bits was incorrect and caused the
scaling values + offsets to be invalid.

Reported-by: Alison Schofield <amsfield22@gmail.com>
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Tested-by: Alison Schofield <amsfield22@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/iio/humidity/hdc100x.c b/drivers/iio/humidity/hdc100x.c
index 1b31841f3039..dc5e7e70f951 100644
--- a/drivers/iio/humidity/hdc100x.c
+++ b/drivers/iio/humidity/hdc100x.c
@@ -164,14 +164,14 @@ static int hdc100x_get_measurement(struct hdc100x_data *data,
 		dev_err(&client->dev, "cannot read high byte measurement");
 		return ret;
 	}
-	val = ret << 6;
+	val = ret << 8;
 
 	ret = i2c_smbus_read_byte(client);
 	if (ret < 0) {
 		dev_err(&client->dev, "cannot read low byte measurement");
 		return ret;
 	}
-	val |= ret >> 2;
+	val |= ret;
 
 	return val;
 }
@@ -212,17 +212,17 @@ static int hdc100x_read_raw(struct iio_dev *indio_dev,
 	case IIO_CHAN_INFO_SCALE:
 		if (chan->type == IIO_TEMP) {
 			*val = 165000;
-			*val2 = 65536 >> 2;
+			*val2 = 65536;
 			return IIO_VAL_FRACTIONAL;
 		} else {
-			*val = 0;
-			*val2 = 10000;
-			return IIO_VAL_INT_PLUS_MICRO;
+			*val = 100;
+			*val2 = 65536;
+			return IIO_VAL_FRACTIONAL;
 		}
 		break;
 	case IIO_CHAN_INFO_OFFSET:
-		*val = -3971;
-		*val2 = 879096;
+		*val = -15887;
+		*val2 = 515151;
 		return IIO_VAL_INT_PLUS_MICRO;
 	default:
 		return -EINVAL;