On Mon, Apr 1, 2019 at 7:13 PM Jonathan Cameron <jonathan.cameron@xxxxxxxxxx> wrote: > > On Mon, 1 Apr 2019 11:25:29 -0300 > Marcelo Schmitt <marcelo.schmitt1@xxxxxxxxx> wrote: > > > Hello, > > > > I was looking for some work on staging: iio: ad9832 and made some > > observations while reading the driver. > > > > Apparently it had no devicetree documentation so I tried to elaborate > > one. > > It uses a platform_data variable to load external clock > > frequency (I tried to make it use linux's clock framework). > Good. > > > Some device attributes don't seem to be standardized on > > Documentation/ABI/testing/sysfs-bus-iio and there's no specific ABI > > for ad9832 nearby nor at staging/iio/Documentation. So maybe those > > missing ABI could be documented. > Beware. It's an old driver, so it may be that we actually want to change > it's ABI rather than documenting what is there (I have haven't looked!) > This one can actually be coupled a bit with the AD9834 driver. There's been some work on trying to move that one out of staging as well. You can take a look at the patches sent for that driver. They should be find-able on patchwork https://patchwork.kernel.org/project/linux-iio/list/?series=&submitter=&state=*&q=ad9834&archive=both&delegate= There are ideas worth borrowing from there. The issue with the AD9834 [if i recall correctly] is that it doesn't quite fit the classical IIO channel model. Meaning, you can only activate the output of one channel at one moment in time, and not both. > > The device has to set some internal registers to operate correctly, > > AD9832_FREQXHM and AD9832_PHASEXH, would it be feasible to set iio > > chanels for this? > > What are they? If they correspond to output channels in some sensible > way then maybe... > > > I couldn't understand why checkpatch.pl gave errors on IIO_DEV_ATTR_* > > macros. To me they seem to have no problem. > > Also it has that platform_data to be moved to include/linux/iio. Is > > there any special reason for it not being there already? Which are > > the criterions a platform_data need to satisfy to be put there? > A driver moving out of staging shouldn't have platform data. It needs > to be converted over to more modern mechanisms. We don't have a problem > supporting platform data for devices that have old school device files > already in tree, but that shouldn't be the case for a driver in staging. > > Hence we can clean it up and move forward with just DT bindings. > > > > I'm sending a patchset with some things I've already done. > Cool. I'll look at those later in the week if no one beats me to them. > > > > > Is there something else that could be done in this device driver? > > Please, tell if I've forgotten something. > > I'll take a look, but it may be a little while before I do. > Hopefully someone else gets there first! > > Jonathan > > > > > Any advice is welcome. > > Thanks, > > > > Marcelo > > _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
