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| author | Carlos Song <carlos.song@nxp.com> | 2022-12-08 10:19:08 +0300 |
|---|---|---|
| committer | Jonathan Cameron <Jonathan.Cameron@huawei.com> | 2022-12-28 20:20:04 +0300 |
| commit | a53f945879c0cb9de3a4c05a665f5157884b5208 (patch) | |
| tree | 88c57089bbc8f5c4a26f2f57b5dc4f3a394eafab /drivers/iio | |
| parent | 37a94d86d7050665d6d01378b2c916c28e454f10 (diff) | |
| download | linux-a53f945879c0cb9de3a4c05a665f5157884b5208.tar.xz | |
iio: imu: fxos8700: fix IMU data bits returned to user space
ACCEL output data registers contain the X-axis, Y-axis, and Z-axis
14-bit left-justified sample data and MAGN output data registers
contain the X-axis, Y-axis, and Z-axis 16-bit sample data. The ACCEL
raw register output data should be divided by 4 before sent to
userspace.
Apply a 2 bits signed right shift to the raw data from ACCEL output
data register but keep that from MAGN sensor as the origin.
Fixes: 84e5ddd5c46e ("iio: imu: Add support for the FXOS8700 IMU")
Signed-off-by: Carlos Song <carlos.song@nxp.com>
Link: https://lore.kernel.org/r/20221208071911.2405922-5-carlos.song@nxp.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers/iio')
| -rw-r--r-- | drivers/iio/imu/fxos8700_core.c | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/drivers/iio/imu/fxos8700_core.c b/drivers/iio/imu/fxos8700_core.c index b62bc92bbacc..06948a8cc315 100644 --- a/drivers/iio/imu/fxos8700_core.c +++ b/drivers/iio/imu/fxos8700_core.c @@ -394,6 +394,7 @@ static int fxos8700_get_data(struct fxos8700_data *data, int chan_type, int axis, int *val) { u8 base, reg; + s16 tmp; int ret; /* @@ -421,8 +422,33 @@ static int fxos8700_get_data(struct fxos8700_data *data, int chan_type, /* Convert axis to buffer index */ reg = axis - IIO_MOD_X; + /* + * Convert to native endianness. The accel data and magn data + * are signed, so a forced type conversion is needed. + */ + tmp = be16_to_cpu(data->buf[reg]); + + /* + * ACCEL output data registers contain the X-axis, Y-axis, and Z-axis + * 14-bit left-justified sample data and MAGN output data registers + * contain the X-axis, Y-axis, and Z-axis 16-bit sample data. Apply + * a signed 2 bits right shift to the readback raw data from ACCEL + * output data register and keep that from MAGN sensor as the origin. + * Value should be extended to 32 bit. + */ + switch (chan_type) { + case IIO_ACCEL: + tmp = tmp >> 2; + break; + case IIO_MAGN: + /* Nothing to do */ + break; + default: + return -EINVAL; + } + /* Convert to native endianness */ - *val = sign_extend32(be16_to_cpu(data->buf[reg]), 15); + *val = sign_extend32(tmp, 15); return 0; } |