Hi Jonathan, On Sun, Jul 2, 2023 at 11:21 AM Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> wrote: [...] > > @@ -235,6 +249,27 @@ enum meson_sar_adc_channel_index { > > NUM_CHAN_7, > > NUM_CHAN_TEMP, > > NUM_CHAN_SOFT_TIMESTAMP, > > Silly question... Why does this device have timestamp channels? > It has no buffer support so they don't 'do anything'. > If it had then putting other channels after that might have broken > things if not done very carefully (hence I went looking) This question is probably for me (not George). The answer is simple: when I wrote the Meson SAR ADC driver I looked at various other drivers (but can't recall which ones exactly). One of them probably used a soft timestamp channel so I also added that to meson_saradc. Since "it didn't break anything" I thought it would be fine. Newer SAR ADC IP blocks have buffer support, but that's not implemented in the driver (yet). So if I understand you correctly we can drop the soft timestamp channel (with a dedicated patch in this series)? Best regards, Martin