From: Stefan Richter Date: Tue, 20 Jan 2009 18:09:58 +0000 (+0100) Subject: ieee1394: ohci1394: increase AT req. retries, fix ack_busy_X from Panasonic camcorder... X-Git-Tag: v2.6.29-rc4~105^2~10 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=64c634ef83991b390ec0503e61f16efb0ba3c60b;p=pandora-kernel.git ieee1394: ohci1394: increase AT req. retries, fix ack_busy_X from Panasonic camcorders and others Camcorders have a tendency to fail read requests to their config ROM and write request to their FCP command register with ack_busy_X. This has become a problem with newer kernels and especially Panasonic camcorders, causing AV/C in dvgrab and kino to fail. Dvgrab for example frequently logs "send oops"; kino reports loss of AV/C control. I suspect that lower CPU scheduling latencies in newer kernels made this issue more prominent now. According to https://sourceforge.net/tracker/?func=detail&atid=114103&aid=2492640&group_id=14103 this can be fixed by configuring the FireWire controller for more hardware retries for request transmission; these retries are evidently more successful than libavc1394's own retry loop (typically 3 tries on top of hardware retries). Presumably the same issue has been reported at https://bugzilla.redhat.com/show_bug.cgi?id=449252 and https://bugzilla.redhat.com/show_bug.cgi?id=477279 . Tested-by: Mathias Beilstein Signed-off-by: Stefan Richter --- Reading git-diff-tree failed