On 26/02/18 13:46, Andy Shevchenko wrote:
On Mon, Feb 26, 2018 at 3:05 PM, Richard Fitzgerald
<rf@xxxxxxxxxxxxxxxxxxxxx> 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
...
+#define MADERA_OTP_HPDET_GRADIENT_1X_MASK 0x0000FF00
+#define MADERA_OTP_HPDET_GRADIENT_0X_MASK 0x000000FF
GENMASK() for all masks?
I'm an un-fan of GENMASK(). It seems to me to make it less readable.
Unless it's important I'd rather leave the masks as they are because
this is all auto-generated from the hardware design. Also keeping it
in plain form like this makes it easier for people converting
settings from the output of codec tuning tools.
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