Hello, CC'ing Sakari. On Wed, Aug 25, 2021 at 02:11:39PM +0100, Mark Brown wrote: > On Wed, Aug 25, 2021 at 03:26:37PM +0300, Andy Shevchenko wrote: > > On Wed, Aug 25, 2021 at 2:30 PM Mark Brown <broonie@xxxxxxxxxx> wrote: > > > > No, what was proposed for regulator was to duplicate all the the DT > > > binding code in the regulator framework so it parses fwnodes then have > > > an API for encoding fwnodes from C data structures at runtime. The bit > > > where the data gets joined up with the devices isn't the problem, it's > > > the duplication and fragility introduced by encoding everything into > > > an intermediate representation that has no purpose and passing that > > > around which is the problem. > > > The whole exercise with swnode is to minimize the driver intrusion and > > evolving a unified way for (some) of the device properties. V4L2 won't > > The practical implementation for regulators was to duplicate a > substantial amount of code in the core in order to give us a less type > safe and more indirect way of passing data from onen C file in the > kernel to another. This proposal is a lot better in that it uses the > existing init_data and avoids the huge amounts of duplication, it's just > not clear from the changelog why it's doing this in a regulator specific > manner. > > *Please* stop trying to force swnodes in everywhere, take on board the > feedback about why the swnode implementation is completely inappropriate > for regulators. I don't understand why you continue to push this so > hard. swnodes and fwnodes are a solution to a specific problem, they're > not the answer to every problem out there and having to rehash this > continually is getting in the way of actually discussing practical > workarounds for these poorly implemented ACPI platforms. > > > like what you are suggesting exactly because they don't like the idea > > of spreading the board code over the drivers. In some cases it might > > even be not so straightforward and easy. > > > Laurent, do I understand correctly the v4l2 expectations? > > There will be some cases where swnodes make sense, for example where the > data is going to be read through the fwnode API since the binding is > firmware neutral which I think is the v4l case. On the other hand > having a direct C representation is a very common way of implementing > DMI quirk tables, and we have things like the regulator API where > there's off the shelf platform data support and we actively don't want > to support fwnode. >From a camera sensor point of view, we want to avoid code duplication. Having to look for regulators using OF lookups *and* platform data in every single sensor driver is not a good solution. This means that, from a camera sensor driver point of view, we want to call regulator_get() (or the devm_ version) with a name, without caring about who establishes the mapping and how the lookup is performed. I don't care much personally if this would be implemented through swnode or a different mechanism, as long as the implementation can be centralized. -- Regards, Laurent Pinchart
