summaryrefslogtreecommitdiff
path: root/include/linux/linear_range.h
AgeCommit message (Collapse)Author
2020-05-08lib: add linear ranges helpersMatti Vaittinen
Many devices have control registers which control some measurable property. Often a register contains control field so that change in this field causes linear change in the controlled property. It is not a rare case that user wants to give 'meaningful' control values and driver needs to convert them to register field values. Even more often user wants to 'see' the currently set value - again in meaningful units - and driver needs to convert the values it reads from register to these meaningful units. Examples of this include: - regulators, voltage/current configurations - power, voltage/current configurations - clk(?) NCOs and maybe others I can't think of right now. Provide a linear_range helper which can do conversion from user value to register value 'selector'. The idea here is stolen from regulator framework and patches refactoring the regulator helpers to use this are following. Current implementation does not support inversely proportional ranges but it might be useful if we could support also inversely proportional ranges? Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/59259bc475e0c800eb4bb163f02528c7c01f7b3a.1588944082.git.matti.vaittinen@fi.rohmeurope.com Signed-off-by: Mark Brown <broonie@kernel.org>