On Wed, Jun 09, 2010 at 09:25:44PM -0400, Jarod Wilson wrote: > On Wed, Jun 9, 2010 at 2:15 PM, Jarod Wilson <jarod@xxxxxxxxxx> wrote: > > On Wed, Jun 09, 2010 at 07:56:21PM +0200, David Härdeman wrote: > >> On Wed, Jun 09, 2010 at 09:29:08AM -0400, Jarod Wilson wrote: > ... > >> > So this definitely negatively impacts my ir-core-to-lirc_dev > >> > (ir-lirc-codec.c) bridge driver, as it was doing the lirc_dev device > >> > registration work in its register function. However, if (after your > >> > patchset) we add a new pair of callbacks replacing raw_register and > >> > raw_unregister, which are optional, that work could be done there instead, > >> > so I don't think this is an insurmountable obstacle for the lirc bits. > >> > >> While I'm not sure exactly what callbacks you're suggesting, > > > > Essentially: > > > > .setup_other_crap > > .tear_down_other_crap > > > > ...which in the ir-lirc-codec case, register ir-lirc-codec for a specific > > hardware receiver as an lirc_dev client, and conversely, tear it down. > > > >> it still > >> sounds like the callbacks would have the exact same problems that the > >> current code has (i.e. the decoder will be blissfully unaware of > >> hardware which exists before the decoder is loaded). Right? > > > > In my head, this was going to work out, but you're correct, I still have > > the exact same problem -- its not in ir_raw_handler_list yet when > > ir_raw_event_register runs, and thus the callback never fires, so lirc_dev > > never actually gets wired up to ir-lirc-codec. It now knows about the lirc > > decoder, but its completely useless. Narf. > > And now I have it working atop your patches. Its a bit of a nasty-ish > hack, at least for the lirc case, but its working, even in the case > where the decoder drivers aren't actually loaded until after the > device driver. I've added one extra param to each protocol-specific > struct in ir-core-priv.h (bool initialized) and hooked into the > protocol-specific decode functions to both determine whether a > protocol should be enabled or disabled by default, and to run any > additionally required initialization (such as in the ir-lirc-codec > case). > > So initially, mceusb comes up with all decoders enabled. Then when ir > comes in, every protocol-specific decoder fires. Each of them check > for whether or not they've been fully initialized, and if not, we > check the loaded keymap, and if it doesn't match, we disable that > decoder (bringing back the "disable protocol handlers we don't need" > functionality that disappeared w/this patchset). In the lirc case, we > actually do all the work needed to wire up the connection over to > lirc_dev. > > This works perfectly fine for all the in-kernel decoders, but has one > minor shortcoming for ir-lirc-codec, in that /dev/lirc0 won't actually > exist until the first incoming ir signal is seen. lircd can handle > this case just fine, it'll wait for /dev/lirc0 to show up, but it > doesn't come up fast enough to catch and decode the very first > incoming ir signal. Subsequent ones work perfectly fine though. This > need to initialize the link via incoming ir is a bit problematic if > you're using a device for transmit-only (e.g., and mceusb device > hooked to a mythtv backend in the closet or something), as there would > be a strong possibility of /dev/lirc0 never getting hooked up. I can > think of a few workarounds, but none are particularly clean and/or > automagic. > > Not sure how palatable it is, but here it is: I think it sounds pretty awful :) I have another suggestion, let's keep the client register/unregister callbacks for decoders (but add a comment that they're only used for lirc). Then teach drivers/media/IR/ir-raw-event.c to keep track of the raw clients so that it can pass all pre-existing clients to newly added decoders. I'll post two patches (compile tested only) in a few seconds to show what I mean. -- David Härdeman -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
