On Mon, Jul 11, 2011 at 1:16 AM, Wolfgang Denk wd@denx.de wrote:
Dear Simon Glass,
In message <CAPnjgZ1Oymaa2_gQGxw88jJG2Kr_fN6tJ5HDgUiOHPjw7jX2= g@mail.gmail.com> you wrote:
Not sure I follow you: the added lines below do indeed add bitfield
access
macros, don't they?
No these are just for defining the shifts and masks. There is no access
But you write yourself in the comment: "...easily getting mask and shift values for bit fields".
The only benefit is to avoid having to calculate all of these masks and shifts in your head. It is basically just a shortcut and assists with checking code against datasheets. Of course I would prefer to have access through macros also but that was shot down so the code is now full of
manual
shifts and ANDs. I hope that at least this small convenience will be acceptable.
Sorry, but because such code is unportable we do not accept it, as it would lead to driver code that becomes unportable, too.
I know that this is throwing more fuel on the fire (for which I am sorry),
but I don't follow the argument that this is unportable. As far as I can tell, the # : # syntax is not using any special compiler extensions, it is simply substituted into a (boo) ? # : # expression, thus extracting either the first of second number from the definition of the bit field.
If I am wrong I would be interested to know what about this is not standard pre-processor usage?
Thanks, Anton
Best regards,
Wolfgang Denk
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