This patch adds compensation formula to raw readings, borrowed
from Memsic's input driver.
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Datasheet says (Page 2) that typical value for sensitivity
for 16 bits mode on Z-axis is 770. Anyhow, looking at the
input driver provided by Memsic the value for MMC35240 is
1024.
Also, testing shows that using 1024 for Z-axis senzitivity
offers better results.
Fixes: abeb6b1e7b ("iio: magnetometer: Add support for MEMSIC MMC35240")
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
According to datasheet, Page 8, minimum wait time to complete
measurement is 10ms. Adjusting this value will increase the
userspace polling rate.
Fixes: abeb6b1e7b ("iio: magnetometer: Add support for MEMSIC MMC35240")
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
The current computation for fractional part of the magnetic
field is broken. This patch fixes it by taking a different
approach. We expose the raw reading in milli Gauss (to avoid
rounding errors) with a scale of 0.001.
Thus the final computation is done in userspace where floating
point operation are more relaxed.
Fixes: abeb6b1e7b ("iio: magnetometer: Add support for MEMSIC MMC35240")
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This avoid nasty crashes when registering the IIO device.
Fixes: abeb6b1e7b ("iio: magnetometer: Add support for MEMSIC MMC35240")
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This is the standard convention for i2c device name and
also this is the name used in some Intel platforms DT
files.
Fixes: abeb6b1e7b ("iio: magnetometer: Add support for MEMSIC MMC35240")
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
The line before limits i to 0-3 so the existing code works fine but the
check is still off by one and >= is intended instead of >.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
We assume that ACPI device tables use MMC35240 to
identify MEMSIC's 3 axis magnetic sensor.
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
We rely on regmap to save the state of the registers at suspend,
and then we do an explicit sync at resume.
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Minimal implementation for MMC35240 3-axis magnetometer
sensor. It provides processed readings and possiblity to change
the sampling frequency.
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Daniel Baluta