On 03/24/11 15:12, Hennerich, Michael wrote: > Jonathan Cameron wrote on 2011-03-24: >> On 03/24/11 14:10, michael.hennerich@xxxxxxxxxx wrote: >>> From: Michael Hennerich <michael.hennerich@xxxxxxxxxx> >> >> Hi Michael, >> >> Some slightly inconsistent handling of the absence of pdata. >> Is it possible to use this device without pdrst being connected? > > Yes and no. > You could but then the AD7780 asserts SDO/RDY whenever a new sample is available. > No way to stop it, without utilizing PDRST. > I therefore use spi bus locking and keep the part in reset/power down whenever is should be quiet. > The part also lacks a dedicated spi chip select. So we definitely want to use PDRST. Fair enough. That's an 'interesting' bit of hardware! > >> If not, then check for pdata early in probe and fail if not present. > > Yes - I typically do this, however it slipped this time. > >> The datardy on the data out line is a delightful big of hardware >> design and I guess what you have here is the only way to handle it. > > Unfortunately that's the case. > >> Having said that, perhaps some explanatory comments, maybe in the >> header, would be useful. Do you have that irq pin dual wired to the >> spi data out? > > Yes > > Thanks for the review. > You are most welcome. -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
