linux-dev/drivers/iio/afe, branch linus/master

iio: afe: rescale: Make use of device properties

2022-04-28T18:22:54Z

Convert the module to be property provider agnostic and allow it to be used on non-OF platforms. Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220413190117.29814-1-andriy.shevchenko@linux.intel.com Signed-off-by: Jonathan Cameron

iio: afe: rescale: add temperature transducers

2022-02-28T10:22:24Z

A temperature transducer is a device that converts a thermal quantity into any other physical quantity. This patch adds support for temperature to voltage (like the LTC2997) and temperature to current (like the AD590) linear transducers. In both cases these are assumed to be connected to a voltage ADC. Signed-off-by: Liam Beguin Reviewed-by: Peter Rosin Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220213025739.2561834-9-liambeguin@gmail.com Signed-off-by: Jonathan Cameron

iio: afe: rescale: add RTD temperature sensor support

2022-02-28T10:22:24Z

An RTD (Resistance Temperature Detector) is a kind of temperature sensor used to get a linear voltage to temperature reading within a give range (usually 0 to 100 degrees Celsius). Common types of RTDs include PT100, PT500, and PT1000. Signed-off-by: Liam Beguin Reviewed-by: Peter Rosin Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220213025739.2561834-8-liambeguin@gmail.com Signed-off-by: Jonathan Cameron

iio: afe: rescale: reduce risk of integer overflow

2022-02-27T13:38:22Z

Reduce the risk of integer overflow by doing the scale calculation on a 64-bit integer. Since the rescaling is only performed on *val, reuse the IIO_VAL_FRACTIONAL_LOG2 case. Signed-off-by: Liam Beguin Reviewed-by: Peter Rosin Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220213025739.2561834-6-liambeguin@gmail.com Signed-off-by: Jonathan Cameron

iio: afe: rescale: fix accuracy for small fractional scales

2022-02-27T13:38:16Z

The approximation caused by integer divisions can be costly on smaller scale values since the decimal part is significant compared to the integer part. Switch to an IIO_VAL_INT_PLUS_NANO scale type in such cases to maintain accuracy. Signed-off-by: Liam Beguin Reviewed-by: Peter Rosin Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220213025739.2561834-5-liambeguin@gmail.com Signed-off-by: Jonathan Cameron

iio: afe: rescale: add offset support

2022-02-27T13:38:10Z

This is a preparatory change required for the addition of temperature sensing front ends. Signed-off-by: Liam Beguin Reviewed-by: Peter Rosin Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220213025739.2561834-4-liambeguin@gmail.com Signed-off-by: Jonathan Cameron

iio: afe: rescale: add INT_PLUS_{MICRO,NANO} support

2022-02-27T13:38:05Z

Some ADCs use IIO_VAL_INT_PLUS_{NANO,MICRO} scale types. Add support for these to allow using the iio-rescaler with them. Signed-off-by: Liam Beguin Reviewed-by: Peter Rosin Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220213025739.2561834-3-liambeguin@gmail.com Signed-off-by: Jonathan Cameron

iio: afe: rescale: expose scale processing function

2022-02-27T13:37:49Z

In preparation for the addition of kunit tests, expose the logic responsible for combining channel scales. Signed-off-by: Liam Beguin Reviewed-by: Peter Rosin Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220213025739.2561834-2-liambeguin@gmail.com Signed-off-by: Jonathan Cameron

iio: afe: rescale: reorder includes

2022-01-30T14:38:03Z

Includes should be ordered alphabetically which is already the case, but follow what is done in other drivers by separation IIO specific headers with a blank line. Signed-off-by: Liam Beguin Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220108205319.2046348-6-liambeguin@gmail.com Signed-off-by: Jonathan Cameron

iio: afe: rescale: use s64 for temporary scale calculations

2022-01-30T14:38:03Z

All four scaling coefficients can take signed values. Make tmp a signed 64-bit integer and switch to div_s64() to preserve signs during 64-bit divisions. Fixes: 8b74816b5a9a ("iio: afe: rescale: new driver") Signed-off-by: Liam Beguin Reviewed-by: Peter Rosin Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220108205319.2046348-5-liambeguin@gmail.com Cc: Signed-off-by: Jonathan Cameron