Steven Toth wrote: > Markus Rechberger wrote: > >> On 8/9/07, Steven Toth <stoth@xxxxxxxxxxxxx> wrote: >> >> >>> Markus Rechberger wrote: >>> >>> >>>> On 8/9/07, Steven Toth <stoth@xxxxxxxxxxxxx> wrote: >>>> >>>> >>>> >>>>> Markus Rechberger wrote: >>>>> >>>>> >>>>> >>>>>> Following patch adds a rather primitive way to temporary lock dvb >>>>>> devicenodes, this can be useful for hybrid devices which use the >>>>>> video4linux framework for the analogue TV part and the dvb framework for >>>>>> digital TV if only one mode can be accessed at a time. >>>>>> >>>>>> Signed-off-by: Markus Rechberger <markus.rechberger@xxxxxxx> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>> Call me dumb but I don't understand how this patch helps v4l devices. :) >>>>> >>>>> Allocation/management of a single card resource doesn't belong inside >>>>> the dvb framework, these answers need to come from the bridge-frameworks >>>>> (via callbacks from dvb-core or the analog equivalent) who are better >>>>> placed to make the decision about hybrid tuners, bus capacity or >>>>> allocation, in use devices. >>>>> >>>>> As a working example, I added similar support in my older HVR3000 tree >>>>> where two frontends share a single transport bus. The code is old but it >>>>> demonstrates a solution, much the my earlier patches for shared >>>>> DVB/Blackbird boards also. >>>>> >>>>> I understand how this patch helps the current dvb tree, it stops >>>>> multiple people opening a device but that's it. ... Or, maybe I've just >>>>> missed to point. >>>>> >>>>> >>>>> >>>>> >>>> Hi Steve, >>>> >>>> the bridge framework triggers locking these filehandles. >>>> >>>> >>>> >>> http://mcentral.de/hg/~mrec/v4l-dvb-experimental/file/c0817d73a2a9/linux/drivers/media/video/em28xx/em28xx-video.c >>> >>> >>>> line 434 >>>> this locks the dvb nodes if someone tries to open the v4l devicenode, >>>> it first checks if there's still something active at the DVB side. >>>> >>>> >>>> >>>> >>> http://mcentral.de/hg/~mrec/v4l-dvb-experimental/file/f9f3e6bdd6fc/linux/drivers/media/video/em28xx/em2880-dvb.c >>> >>> >>>> Line 471 - 484 if this would go into the dvb core we'd have a callback >>>> for locking the device nodes. >>>> >>>> >>>> >>>> >>> Your comment about lines 471-484 make sense, but that code is not >>> referenced via a callback (that I can see in the DVB patch) ... which is >>> what I expected to see. >>> >>> To do this cleanly in the dvb-core (or any v4l-core) I suggest requires >>> callbacks into the bridge-frameworks and I didn't see those callbacks >>> clearly defined in either your original patch, or your follow up >>> patches. I was pretty sure I did something similar for the >>> DVB/MpegEncoder shared bus support. >>> >>> Have you seen this? http://linuxtv.org/hg/~stoth/hvr3000/rev/4b846f1d939b >>> >>> Or more importantly this: >>> http://linuxtv.org/hg/~stoth/hvr3000/rev/a619436699cc >>> >>> Can we just re-use that? >>> >>> >>> >> Since I don't see any move forward from anyone again, can you extract >> that locking callback and submit it independently? I can work around >> the issue that the dvb core still tries to access DVB components after >> a device has been closed, although you might have to verify that issue >> within your drivers too. >> >> >> > Sure, I'll prepare a patch later this evening. > > The ts_bus_ctrl function pointer / callback is already in the mainline, check dvb_frontend.c for more details. You shouldn't need a patch from me. Regards, Steve _______________________________________________ linux-dvb mailing list linux-dvb@xxxxxxxxxxx http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
