[PATCH v2] pinmux: add a driver for the CSR SiRFprimaII pinmux
Arnd Bergmann
arnd at arndb.de
Sat Oct 8 09:08:27 EDT 2011
On Saturday 08 October 2011 19:58:23 Barry Song wrote:
> > You can probably simplify this and other things with
> > preprocessor macros if you want to, like:
> >
> > #define SIRF_FUNC_ENTRY(a) \
> > { .name = "##a##", .pins = ##a##_pins, .num_pins =
> > ARRAY_SIZE(##a##_pins), .padmux = &##a##_padmux }
> >
> > Then just:
> >
> > static const struct sirfsoc_pinmux_func sirfsoc_pinmux_funcs[] = {
> > SIRF_FUNC_ENTRY(lcd_16bits),
> >
> >
> > The macro syntax is probably wrong, the preprocessor always
> > craze me out, but you get the idea.
>
> :-) .name = "##a##" should be changed to .name = #a
>
> #name will convert name into a string "name"
>
Better don't use string concatenation at all if you can avoid it.
A generic macro like
#define SIRF_PINMUX(_name, _pins, _padmux) \
{ .name = (_name), .pins = (_pins), \
.num_pins = ARRAY_SIZE(_pins), padmux = (_padmux), }
is both very easy to understand for someone reading it casually and
lets you actually grep for where the identifiers are being used.
> static const struct sirfsoc_pinmux_func sirfsoc_pinmux_funcs[] = {
> SIRF_FUNC_ENTRY(lcd_16bits),
for the first time, you have no clue what that does, but
static const struct sirfsoc_pinmux_func sirfsoc_pinmux_funcs[] = {
SIRF_PINMUX("lcd_16bits", lcd_16bits_pins, &lcd_16bits_padmux),
...
};
Makes it very clear what you are referencing here and needs no extra lines.
Arnd
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