05.10.2020 12:16, Thierry Reding пишет: ... >> I think you meant regmap in regards to protecting IO accesses, but this >> is not what regmap is about if IO accesses are atomic by nature. > > Then why is there regmap-mmio? To protect programming sequences for example, actually that's the only real use-case I saw in kernel drivers once. In our case there are no sequences that require protection, at least I'm not aware about that. >> Secondly, you're missing that tegra30-devfreq driver will also need to >> perform the MC lookup [3] and then driver will no longer work for the >> older DTs if phandle becomes mandatory because these DTs do not have the >> MC phandle in the ACTMON node. >> >> [3] >> https://github.com/grate-driver/linux/commit/441d19281f9b3428a4db1ecb3a02e1ec02a8ad7f >> >> So we will need the fall back for T30/124 as well. > > No, we don't need the fallback because this is new functionality which > can and should be gated on the existence of the new phandle. If there's > no phandle then we have no choice but to use the old code to ensure old > behaviour. You just repeated what I was trying to say:) Perhaps I spent a bit too much time touching that code to the point that lost feeling that there is a need to clarify everything in details.
