[PATCH 3.19.y-ckt 029/156] iio: adis16480: Fix scale factors

[Kamal Mostafa]

3.19.8-ckt8 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Lars-Peter Clausen <lars at metafoo.de>

commit 7abad1063deb0f77d275c61f58863ec319c58c5c upstream.

The different devices support by the adis16480 driver have slightly
different scales for the gyroscope and accelerometer channels.

Signed-off-by: Lars-Peter Clausen <lars at metafoo.de>
Signed-off-by: Jonathan Cameron <jic23 at kernel.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/iio/imu/adis16480.c | 39 +++++++++++++++++++++++++++++++++------
 1 file changed, 33 insertions(+), 6 deletions(-)

diff --git a/drivers/iio/imu/adis16480.c b/drivers/iio/imu/adis16480.c
index 989605d..b94bfd3 100644
--- a/drivers/iio/imu/adis16480.c
+++ b/drivers/iio/imu/adis16480.c
@@ -110,6 +110,10 @@
 struct adis16480_chip_info {
 	unsigned int num_channels;
 	const struct iio_chan_spec *channels;
+	unsigned int gyro_max_val;
+	unsigned int gyro_max_scale;
+	unsigned int accel_max_val;
+	unsigned int accel_max_scale;
 };
 
 struct adis16480 {
@@ -497,19 +501,21 @@ static int adis16480_set_filter_freq(struct iio_dev *indio_dev,
 static int adis16480_read_raw(struct iio_dev *indio_dev,
 	const struct iio_chan_spec *chan, int *val, int *val2, long info)
 {
+	struct adis16480 *st = iio_priv(indio_dev);
+
 	switch (info) {
 	case IIO_CHAN_INFO_RAW:
 		return adis_single_conversion(indio_dev, chan, 0, val);
 	case IIO_CHAN_INFO_SCALE:
 		switch (chan->type) {
 		case IIO_ANGL_VEL:
-			*val = 0;
-			*val2 = IIO_DEGREE_TO_RAD(20000); /* 0.02 degree/sec */
-			return IIO_VAL_INT_PLUS_MICRO;
+			*val = st->chip_info->gyro_max_scale;
+			*val2 = st->chip_info->gyro_max_val;
+			return IIO_VAL_FRACTIONAL;
 		case IIO_ACCEL:
-			*val = 0;
-			*val2 = IIO_G_TO_M_S_2(800); /* 0.8 mg */
-			return IIO_VAL_INT_PLUS_MICRO;
+			*val = st->chip_info->accel_max_scale;
+			*val2 = st->chip_info->accel_max_val;
+			return IIO_VAL_FRACTIONAL;
 		case IIO_MAGN:
 			*val = 0;
 			*val2 = 100; /* 0.0001 gauss */
@@ -674,18 +680,39 @@ static const struct adis16480_chip_info adis16480_chip_info[] = {
 	[ADIS16375] = {
 		.channels = adis16485_channels,
 		.num_channels = ARRAY_SIZE(adis16485_channels),
+		/*
+		 * storing the value in rad/degree and the scale in degree
+		 * gives us the result in rad and better precession than
+		 * storing the scale directly in rad.
+		 */
+		.gyro_max_val = IIO_RAD_TO_DEGREE(22887),
+		.gyro_max_scale = 300,
+		.accel_max_val = IIO_M_S_2_TO_G(21973),
+		.accel_max_scale = 18,
 	},
 	[ADIS16480] = {
 		.channels = adis16480_channels,
 		.num_channels = ARRAY_SIZE(adis16480_channels),
+		.gyro_max_val = IIO_RAD_TO_DEGREE(22500),
+		.gyro_max_scale = 450,
+		.accel_max_val = IIO_M_S_2_TO_G(12500),
+		.accel_max_scale = 5,
 	},
 	[ADIS16485] = {
 		.channels = adis16485_channels,
 		.num_channels = ARRAY_SIZE(adis16485_channels),
+		.gyro_max_val = IIO_RAD_TO_DEGREE(22500),
+		.gyro_max_scale = 450,
+		.accel_max_val = IIO_M_S_2_TO_G(20000),
+		.accel_max_scale = 5,
 	},
 	[ADIS16488] = {
 		.channels = adis16480_channels,
 		.num_channels = ARRAY_SIZE(adis16480_channels),
+		.gyro_max_val = IIO_RAD_TO_DEGREE(22500),
+		.gyro_max_scale = 450,
+		.accel_max_val = IIO_M_S_2_TO_G(22500),
+		.accel_max_scale = 18,
 	},
 };
 
-- 
1.9.1