On Fri, 28 Jul 2017, Richard Fitzgerald wrote: > This patch adds a header file of register definitions for Cirrus > Logic "Madera" class codecs. These codecs are all based off a common > set of hardware IP so have a common register map (with a few minor > device-to-device variations). > > The registers.h file is tool-generated directly from the hardware design > but has been manually stripped down to reduce size (full register > map is >44000 lines). All names are kept the same as datasheet names > so that they can be cross-referenced between source and datasheet without > confusion. > > The register map layout is kept fully-defined rather than factored into > macros and/or block-indexing code. The major reasons for this are: > > - #1 is that it makes the source highly greppable, which is important. > "What does the driver do with register bits XYZ" or "Where does it use > register bits XYZ" are commonly types of questions. These can be quickly > answered by a grep. Squashing definitions into generator macros or block- > indexing code is a way of defeating grep. > > - most of the register definitions are used in tables, so a constant value > is required. Using generator macros make the table definition clunky and > obscure. > > - the code is clearer when it's there in the source exactly what register > and field it is using > > - it is easier to diff the register map of a new (unsupported) codec against > what is already supported and merge in differences > > - it makes the register map available in source for maintenance/debugging > instead of having to refer back to the datasheet for a register map > > Signed-off-by: Richard Fitzgerald <rf@xxxxxxxxxxxxxxxxxxxxxxxxxxx> > --- > Changes since V3: > - Manually stripped out a lot more stuff, defines we're not using right now > - Added the explanation above to the commit message of why we define the > map effectively verbatim > > MAINTAINERS | 10 + > include/linux/mfd/madera/registers.h | 3987 ++++++++++++++++++++++++++++++++++ > 2 files changed, 3997 insertions(+) > create mode 100644 include/linux/mfd/madera/registers.h For my own reference: Acked-for-MFD-by: Lee Jones <lee.jones@xxxxxxxxxx> -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
