于 2019年7月9日 GMT+08:00 下午4:55:32, Maxime Ripard <maxime.ripard@xxxxxxxxxxx> 写到: >On Mon, Jul 08, 2019 at 05:49:21PM -0700, Vasily Khoruzhick wrote: >> > > Maybe instead of edp-connector one would introduce integrator's >specific >> > > connector, for example with compatible >"olimex,teres-edp-connector" >> > > which should follow edp abstract connector rules? This will be at >least >> > > consistent with below presentation[1] - eDP requirements depends >on >> > > integrator. Then if olimex has standard way of dealing with >panels >> > > present in olimex/teres platforms the driver would then create >> > > drm_panel/drm_connector/drm_bridge(?) according to these rules, I >guess. >> > > Anyway it still looks fishy for me :), maybe because I am not >> > > familiarized with details of these platforms. >> > >> > That makes sense yes >> >> Actually, it makes no sense at all. Current implementation for >anx6345 >> driver works fine as is with any panel specified assuming panel >delays >> are long enough for connected panel. It just doesn't use panel >timings >> from the driver. Creating a platform driver for connector itself >looks >> redundant since it can't be reused, it doesn't describe actual >> hardware and it's just defeats purpose of DT by introducing >> board-specific code. > >I'm not sure where you got the idea that the purpose of DT is to not >have any board-specific code. > >It's perfectly fine to have some, that's even why there's a compatible >assigned to each and every board. > >What the DT is about is allowing us to have a generic behaviour that >we can detect: we can have a given behaviour for a given board, and a >separate one for another one, and this will be evaluated at runtime. > >This is *exactly* what this is about: we can have a compatible that >sets a given, more specific, behaviour (olimex,teres-edp-connector) >while saying that this is compatible with the generic behaviour >(edp-connector). That way, any OS will know what quirk to apply if >needed, and if not that it can use the generic behaviour. > >And we could create a generic driver, for the generic behaviour if >needed. > >> There's another issue: if we introduce edp-connector we'll have to >> specify power up delays somewhere (in dts? or in platform driver?), >so >> edp-connector doesn't really solve the issue of multiple panels with >> same motherboard. > >And that's what that compatible is about :) Maybe we can introduce a connector w/o any driver just like hdmi-connector? > >> I'd say DT overlays should be preferred solution here, not another >> connector binding. > >Overlays are a way to apply a device tree dynamically. It's orthogonal >to the binding. > >Maxime > >-- >Maxime Ripard, Bootlin >Embedded Linux and Kernel engineering >https://bootlin.com -- 使用 K-9 Mail 发送自我的Android设备。