On Tue, 5 Feb 2019 14:22:17 +1100
Stephen Rothwell <[email protected]> wrote:
> Hi Greg,
>
> After merging the staging tree, today's linux-next build (x86_64
> allmodconfig) produced these warnings:
>
> drivers/iio/chemical/sps30.c: In function 'sps30_read_raw':
> drivers/iio/chemical/sps30.c:289:4: warning: this statement may fall through
> [-Wimplicit-fallthrough=]
> switch (chan->channel2) {
> ^~~~~~
> drivers/iio/chemical/sps30.c:299:3: note: here
> default:
> ^~~~~~~
> drivers/iio/chemical/sps30.c: In function 'sps30_do_cmd':
> drivers/iio/chemical/sps30.c:120:10: warning: this statement may fall through
> [-Wimplicit-fallthrough=]
> buf[1] = (u8)SPS30_AUTO_CLEANING_PERIOD;
> ^
> drivers/iio/chemical/sps30.c:121:2: note: here
> case SPS30_READ_DATA_READY_FLAG:
> ^~~~
>
> Introduced by commits
>
> 232e0f6ddeae ("iio: chemical: add support for Sensirion SPS30 sensor")
> 62129a0849d2 ("iio: chemical: sps30: allow changing self cleaning period")
>
> I get this warning because I am building with -Wimplicit-fallthrough
> in attempt to catch new additions early. The gcc warning can be turned
> off by adding a /* fall through */ comment at the point the fall through
> happens (assuming that the fall through is intentional).
>
These both should both be marked - certainly look to be intentional.
The second one might be better handled with an additional return of the -EINVAL.
Thomasz, could you send me a patch tidying this up.
Thanks Stephen!
Jonathan
