bitfield: fix *_encode_bits()
authorJohannes Berg <johannes@sipsolutions.net>
Wed, 20 Jun 2018 06:58:28 +0000 (08:58 +0200)
committerKalle Valo <kvalo@codeaurora.org>
Wed, 27 Jun 2018 15:58:48 +0000 (18:58 +0300)
commite7d4a95da86e0b048702765bbdcdc968aaf312e7
treeaca184c2f1fae9c18e1eb192d9a9bc3de975bc31
parentab8d904654e2bb55b2964588700c31f974382894
bitfield: fix *_encode_bits()

There's a bug in *_encode_bits() in using ~field_multiplier() for
the check whether or not the constant value fits into the field,
this is wrong and clearly ~field_mask() was intended. This was
triggering for me for both constant and non-constant values.

Additionally, make this case actually into an compile error.
Declaring the extern function that will never exist with just a
warning is pointless as then later we'll just get a link error.

While at it, also fix the indentation in those lines I'm touching.

Finally, as suggested by Andy Shevchenko, add some tests and for
that introduce also u8 helpers. The tests don't compile without
the fix, showing that it's necessary.

Fixes: 00b0c9b82663 ("Add primitives for manipulating bitfields both in host- and fixed-endian.")
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
include/linux/bitfield.h