linux-dev/drivers/staging/iio/cdc, branch master

iio: cdc: ad7746: Move driver out of staging.

2022-08-15T21:30:01Z

All known major issues with this driver resolved so time to move it out of staging. This also allows us to remove the now empty staging/iio/cdc directory and build files. Note this cleanup work was done using the roadtest framework. https://lore.kernel.org/all/20220311162445.346685-1-vincent.whitchurch@axis.com/ Signed-off-by: Jonathan Cameron Reviewed-by: Andy Shevchenko

staging: iio: ad7746: White space cleanup

2022-08-15T21:30:01Z

Tidy up some trivial whitespace issues. Signed-off-by: Jonathan Cameron Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220626122938.582107-15-jic23@kernel.org

staging: iio: cdc: ad7746: Use read_avail() rather than opencoding.

2022-08-15T21:30:01Z

Switch over to the IIO core handling for _available attributes making them available for in kernel users and enforcing correct naming etc automatically. Signed-off-by: Jonathan Cameron Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220626122938.582107-14-jic23@kernel.org

staging: iio: cdc: ad7746: Switch from _offset to _zeropoint for differential channels.

2022-08-15T21:30:01Z

As this offset is applied equally to both lines of the differential pair, _ofset should not be used. Use the new ABI _zeropoint instead to avoid userspace software applying this value when calculating real value = (_raw + _offset) * _scale Also add a comment to explain why an offset of 0x800000 is applied within the driver rather than exposed to userspace. Signed-off-by: Jonathan Cameron Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220626122938.582107-13-jic23@kernel.org

staging: iio: cdc: ad7746: Use _raw and _scale for temperature channels.

2022-08-15T21:30:00Z

Performing the maths to rescale a 24 bit raw reading within the driver was resulting in precision losses. So make that userspace's problem by exporting the scale and letting the maths be done in userspace with appropriate precision. Issue identified using roadtester testing framework. Signed-off-by: Jonathan Cameron Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220626122938.582107-11-jic23@kernel.org

staging: iio: cdc: ad7746: Drop unused i2c_set_clientdata()

2022-08-15T21:30:00Z

As the comment states, this was only used in remove() and now there is no explicit remove() function to make use of it. Signed-off-by: Jonathan Cameron Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220626122938.582107-10-jic23@kernel.org

staging: iio: cdc: ad7746: Break up use of chan->address and use FIELD_PREP etc

2022-08-15T21:30:00Z

Instead of encoding several different fields into chan->address use an indirection to a separate per channel structure where the various fields can be expressed in a more readable form. This also allows the register values to be constructed at runtime using FIELD_PREP(). Drop the now redundant _SHIFT macros. Signed-off-by: Jonathan Cameron Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220626122938.582107-9-jic23@kernel.org

staging: iio: cdc: ad7764: Push locking down into case statements in read/write_raw

2022-08-15T21:30:00Z

Not all paths require any locking at all. So to simplify the removal of such locking push the locks down into the individual case statements. Signed-off-by: Jonathan Cameron Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220626122938.582107-8-jic23@kernel.org

staging: iio: cdc: ad7746: Factor out ad7746_read_channel()

2022-08-15T21:30:00Z

Reduce deep indenting and simplify the locking cleanup that follows. Signed-off-by: Jonathan Cameron Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220626122938.582107-7-jic23@kernel.org

staging: iio: cdc: ad7746: Use local buffer for multi byte reads.

2022-08-15T21:30:00Z

I2C does not require DMA safe buffers so there is no need to ensure the buffers are in their own cacheline. Hence simplify things by using a local variable instead of embedding the buffer in the chip info structure. Includes a trivial whitespace cleanup to drop a line between function and error handling. Signed-off-by: Jonathan Cameron Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220626122938.582107-6-jic23@kernel.org