Am Freitag, 1. Dezember 2017, 13:42:46 CET schrieb Doug Anderson: > Hi, > > On Wed, Nov 29, 2017 at 6:27 PM, Chris Zhong <zyw@xxxxxxxxxxxxxx> wrote: > > Hi Doug > > > > Thank you for mentioning this patch. > > > > I think the focus of the discussion is: can we put the grf control bit to > > dts. > > > > The RK3399 has 2 Type-C phy, but only one DP controller, this "uphy_dp_sel" > > > > can help to switch these 2 phy. So I think this bit can be considered as a > > part of > > > > Type-C phy, these 2 phy have different bits, just similar to other bits > > (such as "pipe-status"). > > > > Put them to DTS file might be a accepted practice. > > I guess the first step would be finding the person to make a decision. > Is that Heiko? Olof? Kishon? Rob?. As I see it there are a few > options: > > 1. Land this series as-is. This makes the new bit work just like all > the other ones next to it. If anyone happens to try to use an old > device tree on a new kernel they'll break. Seems rather unlikely > given that the whole type C PHY is not really fully functional > upstream, but technically this is a no-no from a device tree > perspective. > > 2. Change the series to make this property optional. If it's not > there then the code behaves like it always did. This would address > the "compatibility" problem but likely wouldn't actually help any real > people, and it would be extra work. > > 3. Redo the driver to deprecate all the old offsets / bits and just > put the table in the driver, keyed off the compatible string and base > address if the IO memory. > > > I can't make this decision. It's up to those folks who would be > landing the patch and I'd be happy with any of them. What I'm less > happy with, however, is the indecision preventing forward progress. > We should pick one of the above things and land it. My own personal > bias is #1: just land the series. No real people will be hurt and > it's just adding another property that matches the ones next to it. I'd second that #1 . That whole type-c phy thingy never fully worked in the past (some for the never used dp output), so personally I don't have issues with going that route. > From a long term perspective (AKA how I'd write the next driver like > this) I personally lean towards to "tables in the driver, not in the > device tree" but quite honestly I'm happy to take whatever direction > the maintainers give. It looks like we're in agreement here :-) . GRF stuff should not leak into the devicetree, as it causes endless headaches later. But I guess we'll need to live with the ones that happened so far. Heiko -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
