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>> >> - guard(mutex)(&st->lock); > > I would leave this as is. Yes, practically we don't need to cover > iio_backend_has_caps() with mutex to access the data, but it just makes code > slightly more maintainable in my opinion. If anything appears here, it would > probably mean some kind of if (...) do_blablabla(...); pattern that will need > a mutex. I have no strong opinion on this. Current option was chosen as it seemed cleaner in the sense that it a) takes the mutex only when needed and b) check for caps does not require the mutex to be held. Based on this I still suggest keeping as is but will change if you insist. Thanks, Tomas > >> - return ad9467_calibrate(st); >> + if (iio_backend_has_caps(st->back, IIO_BACKEND_CAP_CALIBRATION)) { >> + guard(mutex)(&st->lock); >> + return ad9467_calibrate(st); >> + } >> + return 0; >> } >