On Sat, May 23, 2009 at 11:05 AM, Markus Rechberger <mrechberger@xxxxxxxxx> wrote: > Hi, > > On Sat, May 23, 2009 at 4:49 PM, Markus Rechberger > <mrechberger@xxxxxxxxx> wrote: >> On Sat, May 23, 2009 at 4:04 PM, Markus Rechberger >> <mrechberger@xxxxxxxxx> wrote: >>> Hi, >>> >>> for em28xx devices the device node detection can be based on the >>> encoded endpoint address, for example EP 0x81 (USB IN, Interrupt), >>> 0x82 (analog video EP), 0x83 (analog audio ep), 0x84 (mpeg-ts input >>> EP). >>> It is not necessary that digital TV devices have a frontend, the >>> em28xx chip only specifies an MPEG-TS input EP. >>> >>> Following patch adds a check based on the Endpoints, although it might >>> be extended that all devices match the possible devicenodes based on >>> the endpoints, currently the driver registers an analog TV node by >>> default for all unknown devices which is not necessarily correct, this >>> patch disables the ATV node if no analog TV endpoint is available. >>> >> > > attached patch fixes the deregistration, as well loads the em28xx-dvb > module automatically as soon as an MPEG-TS endpoint was found. > > Signed-off-by: Markus Rechberger <mrechberger@xxxxxxxxx> > > best regards, > Markus > Hello Markus, I spent some time reviewing this patch, and the patch's content does not seem to match your description of its functionality. Further, this patch appears to be a combination of a number of several different changes, rather than being broken into separate patches. First off, I totally agree that the analog subsystem should not be loaded on devices such as em287[0-4]. I was going to do this work (using the chip id to determine analog support) but just had not had a chance to doing the necessary testing to ensure it did not break anything. The patch appears to be primarily for devices that are not supported in the kernel. In fact, the logic as written *only* gets used for unknown devices. Further, the code that doesn't create the frontend device has no application in the kernel. All devices currently in the kernel make use of the dvb frontend interface, so there is no practical application to loading the driver and setting up the isoc handlers but blocking access to the dvb frontend device. Aside from the code that selectively disables analog support, the patch only seems to advance compatibility with your userland em28xx framework while providing no benefit to the in-kernel driver. Regarding the possibility of custom firmware, we currently do not have any devices in the in-kernel driver that make use of custom firmware. If you could tell me how to check for custom firmware versus the default vendor firmware, I could potentially do a patch that uses the vendor registers unless custom firmware is installed, at which point we could have custom logic (such as using the endpoint definition). However, given there are no such devices in-kernel, this is not a high priority as far as I am concerned. For what it's worth, I did add an additional patch to allow the user to disable the 480Mbps check via a modprobe option (to avoid a regression for any of your existing customers), and I will be checking in the code to properly compute the isoc size for em2874/em2884 based on the vendor registers (even though there are currently no supported devices in the kernel that require it currently). However, I do not believe the patch you have proposed is appropriate for inclusion in the mainline kernel. Regards, Devin -- Devin J. Heitmueller - Kernel Labs http://www.kernellabs.com -- 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
