On Mon, Aug 25, 2025 at 10:28:20AM +0200, Nicolas Frattaroli wrote: > This series was spawned by [1], where I was asked to move every instance > of HIWORD_UPDATE et al that I could find to a common macro in the same > series that I am introducing said common macro. > > The first patch of the series introduces a new header file, > hw_bitfield.h, which contains two new macros: FIELD_PREP_WM16 and > FIELD_PREP_WM16_CONST. The latter can be used in initializers. > > I've cheekily added the hw_bitfield.h header to the BITMAP API section > of the MAINTAINERS file. > > This macro definition checks that the mask fits, and that the value fits > in the mask. Like FIELD_PREP, it also shifts the value up to the mask, > so turning off a bit does not require using the mask as a value. Masks > are also required to be contiguous, like with FIELD_PREP. > > For each definition of such a macro, the driver(s) that used it were > evaluated for three different treatments: > - full conversion to the new macro, for cases where replacing the > implementation of the old macro wouldn't have worked, or where the > conversion was trivial. These are the most complex patches in this > series, as they sometimes have to pull apart definitions of masks > and values due to the new semantics, which require a contiguous > mask and shift the value for us. > - replacing the implementation of the old macro with an instance of the > new macro, done where I felt it made the patch much easier to review > because I didn't want to drop a big diff on people. > - skipping conversion entirely, usually because the mask is > non-constant and it's not trivial to make it constant. Sometimes an > added complication is that said non-constant mask is either used in a > path where runtime overhead may not be desirable, or in an > initializer.
Applied in bitmap-for-next for testing. Thanks, Yury
