[PATCH AUTOSEL 5.4 268/350] iio: adis16480: Fix scales factors

Sasha Levin
2019-12-10T21:20:04Z

From: Nuno Sá <nuno.sa@analog.com>

[ Upstream commit 49549cb23a2926eba70bb634e361daea0f319794 ]

This patch fixes the scales for the gyroscope, accelerometer and
barometer. The pressure scale was just wrong. For the others, the scale
factors were not taking into account that a 32bit word is being read
from the device.

Fixes: 7abad1063deb ("iio: adis16480: Fix scale factors")
Fixes: 82e7a1b25017 ("iio: imu: adis16480: Add support for ADIS1649x family of devices")
Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iio/imu/adis16480.c | 77 ++++++++++++++++++++-----------------
1 file changed, 41 insertions(+), 36 deletions(-)

diff --git a/drivers/iio/imu/adis16480.c b/drivers/iio/imu/adis16480.c
index 8743b2f376e27..050652b8fee7b 100644
--- a/drivers/iio/imu/adis16480.c
+++ b/drivers/iio/imu/adis16480.c
@@ -623,9 +623,13 @@ static int adis16480_read_raw(struct iio_dev *indio_dev,
*val2 = (st->chip_info->temp_scale % 1000) * 1000;
return IIO_VAL_INT_PLUS_MICRO;
case IIO_PRESSURE:
- *val = 0;
- *val2 = 4000; /* 40ubar = 0.004 kPa */
- return IIO_VAL_INT_PLUS_MICRO;
+ /*
+ * max scale is 1310 mbar
+ * max raw value is 32767 shifted for 32bits
+ */
+ *val = 131; /* 1310mbar = 131 kPa */
+ *val2 = 32767 << 16;
+ return IIO_VAL_FRACTIONAL;
default:
return -EINVAL;
}
@@ -786,13 +790,14 @@ static const struct adis16480_chip_info adis16480_chip_info[] = {
.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.
+ * Typically we do IIO_RAD_TO_DEGREE in the denominator, which
+ * is exactly the same as IIO_DEGREE_TO_RAD in numerator, since
+ * it gives better approximation. However, in this case we
+ * cannot do it since it would not fit in a 32bit variable.
*/
- .gyro_max_val = IIO_RAD_TO_DEGREE(22887),
- .gyro_max_scale = 300,
- .accel_max_val = IIO_M_S_2_TO_G(21973),
+ .gyro_max_val = 22887 << 16,
+ .gyro_max_scale = IIO_DEGREE_TO_RAD(300),
+ .accel_max_val = IIO_M_S_2_TO_G(21973 << 16),
.accel_max_scale = 18,
.temp_scale = 5650, /* 5.65 milli degree Celsius */
.int_clk = 2460000,
@@ -802,9 +807,9 @@ static const struct adis16480_chip_info adis16480_chip_info[] = {
[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),
+ .gyro_max_val = 22500 << 16,
+ .gyro_max_scale = IIO_DEGREE_TO_RAD(450),
+ .accel_max_val = IIO_M_S_2_TO_G(12500 << 16),
.accel_max_scale = 10,
.temp_scale = 5650, /* 5.65 milli degree Celsius */
.int_clk = 2460000,
@@ -814,9 +819,9 @@ static const struct adis16480_chip_info adis16480_chip_info[] = {
[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),
+ .gyro_max_val = 22500 << 16,
+ .gyro_max_scale = IIO_DEGREE_TO_RAD(450),
+ .accel_max_val = IIO_M_S_2_TO_G(20000 << 16),
.accel_max_scale = 5,
.temp_scale = 5650, /* 5.65 milli degree Celsius */
.int_clk = 2460000,
@@ -826,9 +831,9 @@ static const struct adis16480_chip_info adis16480_chip_info[] = {
[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),
+ .gyro_max_val = 22500 << 16,
+ .gyro_max_scale = IIO_DEGREE_TO_RAD(450),
+ .accel_max_val = IIO_M_S_2_TO_G(22500 << 16),
.accel_max_scale = 18,
.temp_scale = 5650, /* 5.65 milli degree Celsius */
.int_clk = 2460000,
@@ -838,9 +843,9 @@ static const struct adis16480_chip_info adis16480_chip_info[] = {
[ADIS16495_1] = {
.channels = adis16485_channels,
.num_channels = ARRAY_SIZE(adis16485_channels),
- .gyro_max_val = IIO_RAD_TO_DEGREE(20000),
- .gyro_max_scale = 125,
- .accel_max_val = IIO_M_S_2_TO_G(32000),
+ .gyro_max_val = 20000 << 16,
+ .gyro_max_scale = IIO_DEGREE_TO_RAD(125),
+ .accel_max_val = IIO_M_S_2_TO_G(32000 << 16),
.accel_max_scale = 8,
.temp_scale = 12500, /* 12.5 milli degree Celsius */
.int_clk = 4250000,
@@ -851,9 +856,9 @@ static const struct adis16480_chip_info adis16480_chip_info[] = {
[ADIS16495_2] = {
.channels = adis16485_channels,
.num_channels = ARRAY_SIZE(adis16485_channels),
- .gyro_max_val = IIO_RAD_TO_DEGREE(18000),
- .gyro_max_scale = 450,
- .accel_max_val = IIO_M_S_2_TO_G(32000),
+ .gyro_max_val = 18000 << 16,
+ .gyro_max_scale = IIO_DEGREE_TO_RAD(450),
+ .accel_max_val = IIO_M_S_2_TO_G(32000 << 16),
.accel_max_scale = 8,
.temp_scale = 12500, /* 12.5 milli degree Celsius */
.int_clk = 4250000,
@@ -864,9 +869,9 @@ static const struct adis16480_chip_info adis16480_chip_info[] = {
[ADIS16495_3] = {
.channels = adis16485_channels,
.num_channels = ARRAY_SIZE(adis16485_channels),
- .gyro_max_val = IIO_RAD_TO_DEGREE(20000),
- .gyro_max_scale = 2000,
- .accel_max_val = IIO_M_S_2_TO_G(32000),
+ .gyro_max_val = 20000 << 16,
+ .gyro_max_scale = IIO_DEGREE_TO_RAD(2000),
+ .accel_max_val = IIO_M_S_2_TO_G(32000 << 16),
.accel_max_scale = 8,
.temp_scale = 12500, /* 12.5 milli degree Celsius */
.int_clk = 4250000,
@@ -877,9 +882,9 @@ static const struct adis16480_chip_info adis16480_chip_info[] = {
[ADIS16497_1] = {
.channels = adis16485_channels,
.num_channels = ARRAY_SIZE(adis16485_channels),
- .gyro_max_val = IIO_RAD_TO_DEGREE(20000),
- .gyro_max_scale = 125,
- .accel_max_val = IIO_M_S_2_TO_G(32000),
+ .gyro_max_val = 20000 << 16,
+ .gyro_max_scale = IIO_DEGREE_TO_RAD(125),
+ .accel_max_val = IIO_M_S_2_TO_G(32000 << 16),
.accel_max_scale = 40,
.temp_scale = 12500, /* 12.5 milli degree Celsius */
.int_clk = 4250000,
@@ -890,9 +895,9 @@ static const struct adis16480_chip_info adis16480_chip_info[] = {
[ADIS16497_2] = {
.channels = adis16485_channels,
.num_channels = ARRAY_SIZE(adis16485_channels),
- .gyro_max_val = IIO_RAD_TO_DEGREE(18000),
- .gyro_max_scale = 450,
- .accel_max_val = IIO_M_S_2_TO_G(32000),
+ .gyro_max_val = 18000 << 16,
+ .gyro_max_scale = IIO_DEGREE_TO_RAD(450),
+ .accel_max_val = IIO_M_S_2_TO_G(32000 << 16),
.accel_max_scale = 40,
.temp_scale = 12500, /* 12.5 milli degree Celsius */
.int_clk = 4250000,
@@ -903,9 +908,9 @@ static const struct adis16480_chip_info adis16480_chip_info[] = {
[ADIS16497_3] = {
.channels = adis16485_channels,
.num_channels = ARRAY_SIZE(adis16485_channels),
- .gyro_max_val = IIO_RAD_TO_DEGREE(20000),
- .gyro_max_scale = 2000,
- .accel_max_val = IIO_M_S_2_TO_G(32000),
+ .gyro_max_val = 20000 << 16,
+ .gyro_max_scale = IIO_DEGREE_TO_RAD(2000),
+ .accel_max_val = IIO_M_S_2_TO_G(32000 << 16),
.accel_max_scale = 40,
.temp_scale = 12500, /* 12.5 milli degree Celsius */
.int_clk = 4250000,
--
2.20.1