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be8dcab942
Add quirk for VT6306 wake bit behavior. VT6306 seems to reread the wrong descriptor when the wake bit is written. work around by putting a copy of the branch address in the first descriptor of the block. [Stefan R: This fixes the known broken video reception via gstreamer on VIA VT6306. 100% repeatable testcase: $ gst-launch-0.10 dv1394src \! dvdemux \! dvdec \! xvimagesink with a camcorder or other DV source connected. Likewise for MPEG2-TS reception via gstreamer, e.g. from TV settop boxes. Perhaps this also fixes dv4l on VT6306, but this is as yet untested. Kino, dvgrab or FFADO had not been affected by this chip quirk. Additional comments from Andy:] I've looked into some problems with the wake bit on a vt6306 family chip (1106:3044, rev 46). I used this firewire card in a mythtv setup (ISO receive MPEG2 stream) with Debian 2.6.32 kernels for ~2 years without problems. Since upgrading to 3.2, I've been having problems with the input stream freezing -- input data stops until I restart mythtv (I expect closing and reopening the device would be sufficient). This happens infrequently, maybe one out of 20 recordings. I eventually determined that the problem is more likely to occur if the system is loaded. I isolated the kernel version as the triggering SW factor and then specifically the change from dualbuffer back to packet-per-buffer DMA mode. The possibility that the controller does not properly respond to the wake bit was suggested in https://bugzilla.redhat.com/show_bug.cgi?id=415841, but not proven. Based on the fact that dualbuffer mode worked while packet-per-buffer has trouble, I guessed that upon seeing the wake bit written, the vt6306 controller only checks the branch address in the first descriptor of the block, even if that is not the correct place to look (because the block has multiple descriptors). This theory seems to be correct. When the ISO reception is hung, I am able to resume it by manually writing the branch address to the first descriptor in the block, and then writing the wake bit. I've had luck so far with the attached patch, so I'm including it. It's probably not a complete solution -- I haven't tested transmit modes to see whether they have a similar issue. I doubt that the quirk test is any cheaper than just writing the extra branch address in all cases, but it does reduce the risk of breaking other hardware. [Stefan R: omitted QUIRK_NO_MSI from VT6306 quirks table entry, changed whitespace] Signed-off-by: Andy Leiserson <andy@leiserson.org> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> |
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| .. | ||
| core-card.c | ||
| core-cdev.c | ||
| core-device.c | ||
| core-iso.c | ||
| core-topology.c | ||
| core-transaction.c | ||
| core.h | ||
| init_ohci1394_dma.c | ||
| Kconfig | ||
| Makefile | ||
| net.c | ||
| nosy-user.h | ||
| nosy.c | ||
| nosy.h | ||
| ohci.c | ||
| ohci.h | ||
| sbp2.c | ||