On Tue, May 20, 2014 at 04:47:12PM +0200, Andreas Herrmann wrote: > + > +union pci_config_address { > + struct { > +#ifdef __LITTLE_ENDIAN > + unsigned register_number : 8; /* 7 .. 0 */ > + unsigned devfn_number : 8; /* 15 .. 8 */ > + unsigned bus_number : 8; /* 23 .. 16 */ > + unsigned reserved : 7; /* 30 .. 24 */ > + unsigned enable_bit : 1; /* 31 */ > +#else > + unsigned enable_bit : 1; /* 31 */ > + unsigned reserved : 7; /* 30 .. 24 */ > + unsigned bus_number : 8; /* 23 .. 16 */ > + unsigned devfn_number : 8; /* 15 .. 8 */ > + unsigned register_number : 8; /* 7 .. 0 */ > +#endif For this kind of endianess dependency there is a more elegant way of defining things in linux-next's <uapi/asm/bitfield.h> like: #include <uapi/asm/bitfield.h> ... struct { __BITFIELD_FIELD(unsigned enable_bit : 1, /* 31 */ __BITFIELD_FIELD(unsigned reserved : 7, /* 30 .. 24 */ __BITFIELD_FIELD(unsigned bus_number : 8, /* 23 .. 16 */ __BITFIELD_FIELD(unsigned devfn_number : 8, /* 15 .. 8 */ __BITFIELD_FIELD(unsigned register_number : 8, /* 7 .. 0 */ ))))); }; No ifdef, no duplication! Ralf