lkml.org 
[lkml]   [2009]   [Feb]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[patch 17/56] ieee1394: ohci1394: increase AT req. retries, fix ack_busy_X from Panasonic camcorders and others
2.6.27-stable review patch.  If anyone has any objections, please let us know.
------------------

From: Stefan Richter <stefanr@s5r6.in-berlin.de>

Commit 64c634ef83991b390ec0503e61f16efb0ba3c60b upstream.

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 <stefanr@s5r6.in-berlin.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/ieee1394/ohci1394.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/ieee1394/ohci1394.h
+++ b/drivers/ieee1394/ohci1394.h
@@ -26,7 +26,7 @@

#define OHCI1394_DRIVER_NAME "ohci1394"

-#define OHCI1394_MAX_AT_REQ_RETRIES 0x2
+#define OHCI1394_MAX_AT_REQ_RETRIES 0xf
#define OHCI1394_MAX_AT_RESP_RETRIES 0x2
#define OHCI1394_MAX_PHYS_RESP_RETRIES 0x8
#define OHCI1394_MAX_SELF_ID_ERRORS 16


\
 
 \ /
  Last update: 2009-02-11 01:35    [W:0.174 / U:0.280 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site