On Thu, Aug 04, 2022 at 08:28:28PM +0200, Andy Shevchenko wrote:
> > > > +static const struct {
> > > > + int val;
> > > > + int val2;
> > > > +} msa311_fs_table[] = {
> > > > + {0, 9580}, {0, 19160}, {0, 38320}, {0, 76641}
> > > > +};
> > >
> > > Besides that this struct is defined not only once in the file, this is
> > > very well NIH struct s32_fract. Why not use the latter?
>
> > Good point, but looks like this struct is not so popular in the other
> > kernel drivers:
>
> It's simply new, it is not about popularity. I would put it as it's
> not _yet_ so popular.
Okay, no problem. I've already reworked it to s32_fract locally.
>
> ...
>
> > grep "s32_fract" -r -l . | wc -l
> > 3
>
> Hint: `git grep` much much faster on Git repositories (it goes via
> index and not working copy) and see
> `git grep -lw s32_fract`
>
Thank you for the hint. Actually I'm using ripgrep for the kernel
fuzzysearching, it's faster than git grep. Here I gave an example based
on grep command, because it's general shell command for the searching
substrings I suppose.
> ...
>
> > > > + .cache_type = REGCACHE_RBTREE,
> > >
> > > Tree hash is good for sparse data, do you really have it sparse (a lot
> > > of big gaps in between)?
> >
> > I suppose so. MSA311 regmap has ~6 gaps.
>
> Yes and how long is each gap in comparison to the overall space?
The longest gap is 0xb bytes.
>
> ...
>
> > > > + for (fs = 0; fs < ARRAY_SIZE(msa311_fs_table); ++fs)
> > >
> > > fs++ will work as well.
> >
> > I would prefer ++fs if you don't mind :)
>
> Why? It's a non-standard pattern, and needs an explanation.
>
>From statistics point of view, you are right :)
$ rg "for" | rg "\+\+[a-z]" | wc -l
7271
$ rg "for" | rg "[a-z]\+\+" | wc -l
81247
[...]
> > > > + dev_err(dev, "cannot update freq (%d)\n", err);
> > >
> > > frequency
> >
> > It will be more ugly due 80 symbols restriction.
>
> Nope, it will be understandable by the user. You do code for the user
> and then for the developer, right?
Sure, that's good point.
[...]
>
> ...
>
> > > > + dev_dbg(dev, "found MSA311 compatible chip[%#x]\n", partid);
> > >
> > > Useless message.
> >
> > Why? It's under dynamic debug, so I will see it if I really want to.
>
> So what the point of the _successful_ detection? You already know from
> the code, that partid, you know by other means that probe was
> successful, why this message is needed? Especially for debugging when
> we have initcall_debug option.
>
Agreed
[...]
--
Thank you,
Dmitry
