On Wed, Mar 18, 2020 at 01:42:26PM +0000, Vaittinen, Matti wrote: > Hello Greg, > > On Wed, 2020-03-18 at 14:08 +0100, Greg Kroah-Hartman wrote: > > On Tue, Feb 25, 2020 at 10:53:01AM +0200, Matti Vaittinen wrote: > > > 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. > > > > > > Signed-off-by: Matti Vaittinen <matti.vaittinen@xxxxxxxxxxxxxxxxx> > > > --- > > > > > > Changes since rfc-v3: > > > - Kerneldoc fixes > > > - Corrected commit message typo meaningfull => meaningful > > > > > > drivers/base/Kconfig | 3 + > > > drivers/base/Makefile | 1 + > > > drivers/base/linear_ranges.c | 246 > > > +++++++++++++++++++++++++++++++++++ > > > > Why in drivers/base/ ? > > > > Why not in lib/ ? > > I was pondering which of these would be better. I decided to do with > drivers/base because - in it's current form - this is really a driver > related stuff. I see it somehow in same position as regmap code - > although this is just a tiny helper compared to regmap. But this also > has pretty driver specific audience :) > > And... I must admit I like things which I know. And I have been doing > driver development and "know" a few of the driver related colleagues - > hence working with them is easier for me ;) Getting to know the > colleagues maintaining lib is a bit scary :] Yep, I'm Finnish if you > happen to wonder why getting to know people is scary xD > > > > > > include/linux/linear_range.h | 48 +++++++ > > > 4 files changed, 298 insertions(+) > > > create mode 100644 drivers/base/linear_ranges.c > > > create mode 100644 include/linux/linear_range.h > > > > > > diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig > > > index 5f0bc74d2409..636b6fa8e499 100644 > > > --- a/drivers/base/Kconfig > > > +++ b/drivers/base/Kconfig > > > @@ -209,4 +209,7 @@ config GENERIC_ARCH_TOPOLOGY > > > appropriate scaling, sysfs interface for reading capacity > > > values at > > > runtime. > > > > > > +config LINEAR_RANGES > > > + tristate > > > > No help text at all??? > > Yes. The linear ranges has no meaning to be enabled alone. It only > plays a role if it is used by some driver/subsystem. And > drivers/subsystems should do > select LINEAR_RANGES. So showing help in any config tool is not needed. > This should actually not be visible in menuconfig or others. I think I > have seen a few examples like this. > > Ayways, I have no obejctions to adding some text if absolutely needed. > Any suggestions for a text politely saying - "please, pretend I am not > here" - are welcome :) (Although, I think this really does not need > help text). This kind of implies it needs to be in lib/ that way the needed code links it and all should be fine. thanks, greg k-h
