On Mon, Aug 16, 2021 at 12:35 AM Liam Beguin <liambeguin@xxxxxxxxx> wrote: > > While working on another series[1] I ran into issues where my SPI > controller would fail to handle 14-bit and 16-bit SPI messages. This > addresses that issue and adds support for selecting a different voltage > reference source from the devicetree. > > v1 was base on a series[2] that seems to not have made it all the way, > and was tested on an ad7689. > > v6 drops support for per channel vref selection. > After switching the voltage reference, readings take a little while to > stabilize, invalidating consecutive readings. > > This could've been addressed by adding more dummy cycles at the expense > of speed, but discussing the issue with colleagues more involved in > hardware design, it turns out these circuits are usually designed with a > single vref in mind. > > [1] https://patchwork.kernel.org/project/linux-iio/list/?series=511545 > [2] https://patchwork.kernel.org/project/linux-iio/list/?series=116971&state=%2A&archive=both > > Changes since v5: > - rename defines: s/AD7949_CFG_BIT_/AD7949_CFG_MASK_/g > - rename AD7949_MASK_TOTAL to match other defines > - make vref selection global instead of per channel, and update > dt-bindings Same as per v5: is it a hardware limitation? It's unclear to me what happened here. > - reword commits 2/5, 3/5, and 4/5 > - move bits_per_word configuration to struct spi_device, and switch to > spi_{read,write}. -- With Best Regards, Andy Shevchenko
