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>>   int ret; >>   >> + if (!st->back) >> + return -EOPNOTSUPP; >> + > > Let's not add the buffering interface if we can't control it. > Having it just to return error does not make sense to me. This means yet another info: > > https://elixir.bootlin.com/linux/v6.18.1/source/drivers/iio/adc/ad9467.c#L916 > I agree, not having the scan_mode at all would be more clean. But adding those different iio_info structs comes across as a bit messy. Would it make sense to create that iio_info dynamically in the probe and fill out the callbacks that are supported for the configuration we encounter? I could try out something like that and see how it would look like in practice. Thanks, Tomas > Also the channel definition should not have the scan index. But, given that the IIO device > won't have any buffer I think there's no way to reach ad9467_update_scan_mode() (unless I'm > missing something). > > Still, while I understand that updating the channels to not include the scan_index is very > cumbersome, having a new iio_info with no .update_scan_mode() is trivial and make things > more clear and explicit. > > - Nuno Sá >