On 12/13/2012 11:09 PM, Terje Bergström wrote: > On 13.12.2012 19:58, Stephen Warren wrote: >> On 12/13/2012 01:57 AM, Thierry Reding wrote: >>> After some more discussion with Stephen on IRC we came to the >>> conclusion that the easiest might be to have tegra-drm call into >>> host1x with something like: >>> >>> void host1x_set_drm_device(struct host1x *host1x, struct device >>> *dev); >> >> If host1x is registering the dummy device that causes tegradrm to be >> instantiated, then presumably there's no need for the API above, since >> host1x will already have the struct device * for tegradrm, since it >> created it? > > I didn't add the dummy device in my latest patch set. I first set out to > add it, and moved the drm global data to be drvdata of that device. Then > I noticed that it doesn't actually help at all. > > The critical accesses to the global data are from probes of DC, HDMI, > etc. OK > They want to get the global data by getting drvdata of their parent. There's no reason that /has/ to be so; they can get any information from wherever it is, rather than trying to require it to be somewhere it isn't. > The dummy device is not their parent - host1x is. There's no > connection between the dummy and the real client devices. It's quite possible for the client devices to ask their actual parent (host1x) for the tegradrm struct device *, by calling a host1x API, and have host1x implement that API by returning the dummy/virtual device that it created. That should be just 1-2 lines of code to implement in host1x, plus maybe a couple more to correctly return -EPROBE_DEFERRED when appropriate. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
