Re: IO, ANSI vs GCC structs

In message [ref] you wrote:

How important is it to the kernel coding style that hardware be

I cannot speak for the powers that be, but...

accessed through a structure?  Is it acceptable to do:

  #define MYHW  (MY_MBAR+42)

  ...

  out_be32(MYHW, 0xco1df00d);

...I would not accept such code.

There is one fundamental difference: a field in a struct has a  type,
i.  e.  the  compiler "knows" how big it is (8, 16, 32, ... bits), if
special attributes apply (volatile), etc.

There is no such information with a #define like yours above.

OK, you can write

	#define FOO	((volatile uint32_t *)(FOO_BASE+FOO_OFFSET))

but this isn't really readable, is it?

Just my $0.02


Best regards,

Wolfgang Denk

--
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd@denx.de
They say a little knowledge is a dangerous thing,  but it is not  one
half so bad as a lot of ignorance.   - Terry Pratchett, _Equal Rites_

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