Dear Simon Glass,
In message BANLkTimCGQbih16u7772-uKHb0bUyApbe14mNQ91zhqi1SS62w@mail.gmail.com you wrote:
OK I understand, thank you. How about this approach: we could add a new macro to io.h, something like:
#define clrsetfield_le32(bitfield, addr, value) ...
Then caller can define these in a header file:
#define FIELD_MASK 0xf0000 #define FIELD_SHIFT 16
And use this macro to set the bitfield to 6, for example:
clrsetfield_le32(FIELD, &my_device->ctrl, 6)
(this will simply shift the value left 16 bits and apply the supplied mask)
This captures the essence of bitfields, in that we are abstracting the field under a single name. The change would just add this macro to the io.h header file.
Sorry, I fail to understand how you envision to use this, and how it would be different from clrsetbits*() ?
Best regards,
Wolfgang Denk