In order to avoid unnecessary pollution of the global symbol namespace
move the common/library functions into a specific namespace and import
that into the bus specific device drivers that use them.
For more information see https://lwn.net/Articles/760045/
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Himanshu Jha <himanshujha199640@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220130205701.334592-17-jic23@kernel.org
BME0680 is not an official ACPI ID, so let's remove it before someone
starts using it.
Note that ACPI can still be used with this driver via the PRP0001 method
which will use the of_device_id table to match.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The SPI interface implementation was completely broken.
When using the SPI interface, there are only 7 address bits, the upper bit
is controlled by a page select register. The core needs access to both
ranges, so implement register read/write for both regions. The regmap
paging functionality didn't agree with a register that needs to be read
and modified, so I implemented a custom paging algorithm.
This fixes that the device wouldn't even probe in SPI mode.
The SPI interface then isn't different from I2C, merged them into the core,
and the I2C/SPI named registers are no longer needed.
Implemented register value caching for the registers to reduce the I2C/SPI
data transfers considerably.
The calibration set reads as all zeroes until some undefined point in time,
and I couldn't determine what makes it valid. The datasheet mentions these
registers but does not provide any hints on when they become valid, and they
aren't even enumerated in the memory map. So check the calibration and
retry reading it from the device after each measurement until it provides
something valid.
Despite the size this is suitable for a stable backport given that
it seems the SPI support never worked.
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Fixes: 1b3bd85927 ("iio: chemical: Add support for Bosch BME680 sensor");
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit allow the driver to work with device-tree.
Signed-off-by: Sebastien Bourdelin <sebastien.bourdelin@gmail.com>
Acked-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Bosch BME680 is a 4-in-1 sensor with temperature, pressure, humidity
and gas sensing capability. It supports both I2C and SPI communication
protocol for effective data communication.
The device supports two modes:
1. Sleep mode
2. Forced mode
The measurements only takes place when forced mode is triggered and a
single TPHG cycle is performed by the sensor. The sensor automatically
goes to sleep after afterwards.
The device has various calibration constants/parameters programmed into
devices' non-volatile memory(NVM) during production and can't be altered
by the user. These constants are used in the compensation functions to
get the required compensated readings along with the raw data. The
compensation functions/algorithms are provided by Bosch Sensortec GmbH
via their API[1]. As these don't change during the measurement cycle,
therefore we read and store them at the probe. The default configs
supplied by Bosch are also set at probe.
0-day tested with build success.
GSoC-2018: https://summerofcode.withgoogle.com/projects/#6691473790074880
Mentor: Daniel Baluta
[1] https://github.com/BoschSensortec/BME680_driver
Datasheet:
https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BME680-DS001-00.pdf
Note from Jonathan: The compensation functions are 'interesting' and
could do with a tidy up in future. However, they work so we can leave that
for another day.
Cc: Daniel Baluta <daniel.baluta@nxp.com>
Signed-off-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
