> > > +}; > > > + > > > +static int ad8460_get_powerdown_mode(struct iio_dev *indio_dev, > > > + const struct iio_chan_spec *chan) { > > > + return 0; > > > > Why have the stubs in here? > > Should I move the stubs to a different place in the code or remove them > altogether since there is only a single powerdown mode available Ah. I'd not really understood what was going on here. This is fine as is. > > AD8460_HVDAC_DATA_WORD_HIGH(index), > > > + ((val >> 8) & 0xFF)); > > > > bulk write? or do these need to be ordered? > > For this I used bulk read/write this way. > > static int ad8460_set_hvdac_word(struct ad8460_state *state, > int index, > int val) > { > u8 regvals[AD8460_DATA_BYTE_WORD_LENGTH]; regmap bulk accesses (when spi anyway) should be provided with DMA safe buffers. Easiest way to do that is add one with __aligned(IIO_DMA_MINALIGN) to the end of the ad8460_state structure. Possibly you'll need a lock to protect it - I haven't checked. > > regvals[0] = val & 0xFF; > regvals[1] = (val >> 8) & 0xFF; That is an endian conversion so use appropriate endian function to fill it efficiently and document clearly what is going on. put_unaligned_le16() > > return regmap_bulk_write(state->regmap, AD8460_HVDAC_DATA_WORD_LOW(index), > regvals, AD8460_DATA_BYTE_WORD_LENGTH); > } > > > > > +} > > > + state->regmap = devm_regmap_init_spi(spi, &ad8460_regmap_config); > > > + if (IS_ERR(state->regmap)) > > > + return dev_err_probe(&spi->dev, PTR_ERR(state->regmap), > > > + "Failed to initialize regmap"); > > > + > > > + ret = devm_iio_dmaengine_buffer_setup_ext(&spi->dev, indio_dev, "tx", > > > + > > IIO_BUFFER_DIRECTION_OUT); > > > > Ah. I take back my binding comment. I assume this is mapping some non > > standard interface for the parallel data flow? > > Yes, the HDL side doesn't follow yet the standard IIO backend from which this > driver was tested Hmm. I'd like to see this brought inline with the other iio backend drivers if possible. Jonathan