linux/drivers/media/dvb-core
Jasmin J e7080d4471 [media] media/dvb-core: Race condition when writing to CAM
It started with a sporadic message in syslog: "CAM tried to send a
buffer larger than the ecount size" This message is not the fault
itself, but a consecutive fault, after a read error from the CAM. This
happens only on several CAMs, several hardware, and of course sporadic.

It is a consecutive fault, if the last read from the CAM did fail. I
guess this will not happen on all CAMs, but at least it did on mine.
There was a write error to the CAM and during the re-initialization
procedure, the CAM finished the last read, although it got a RS.

The write error to the CAM happened because a race condition between HC
write, checking DA and FR.

This patch added an additional check for DA(RE), just after checking FR.
It is important to read the CAMs status register again, to give the CAM
the necessary time for a proper reaction to HC. Please note the
description within the source code (patch below).

[mchehab@s-opensource.com: make checkpatch happy]

Signed-off-by: Jasmin jessich <jasmin@anw.at>
Tested-by: Ralph Metzler <rjkm@metzlerbros.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-04-17 17:20:23 -03:00
..
demux.h [media] media: Drop FSF's postal address from the source code files 2017-01-27 11:38:09 -02:00
dmxdev.c [media] media: dvb: dmx: fixed coding style issues of spacing 2017-02-03 11:35:10 -02:00
dmxdev.h [media] media: Drop FSF's postal address from the source code files 2017-01-27 11:38:09 -02:00
dvb_ca_en50221.c [media] media/dvb-core: Race condition when writing to CAM 2017-04-17 17:20:23 -03:00
dvb_ca_en50221.h [media] dvb_ca_en50221.h: Make checkpatch.pl happy 2015-10-06 18:40:01 -03:00
dvb_demux.c sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h> 2017-03-02 08:42:32 +01:00
dvb_demux.h [media] media: Drop FSF's postal address from the source code files 2017-01-27 11:38:09 -02:00
dvb_frontend.c sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h> 2017-03-02 08:42:32 +01:00
dvb_frontend.h [media] docs-rst: media: better document refcount in struct dvb_frontend 2017-04-17 16:55:38 -03:00
dvb_math.c [media] media: Drop FSF's postal address from the source code files 2017-01-27 11:38:09 -02:00
dvb_math.h [media] media: Drop FSF's postal address from the source code files 2017-01-27 11:38:09 -02:00
dvb_net.c [media] media: Drop FSF's postal address from the source code files 2017-01-27 11:38:09 -02:00
dvb_net.h [media] media: Drop FSF's postal address from the source code files 2017-01-27 11:38:09 -02:00
dvb_ringbuffer.c [media] media: Drop FSF's postal address from the source code files 2017-01-27 11:38:09 -02:00
dvb_ringbuffer.h scripts/spelling.txt: add "an user" pattern and fix typo instances 2017-02-27 18:43:46 -08:00
dvb-usb-ids.h [media] add Hama Hybrid DVB-T Stick support 2017-02-08 10:54:58 -02:00
dvbdev.c [media] media: Drop FSF's postal address from the source code files 2017-01-27 11:38:09 -02:00
dvbdev.h [media] media: Drop FSF's postal address from the source code files 2017-01-27 11:38:09 -02:00
Kconfig [media] Raise adapter number limit 2016-11-23 13:28:43 -02:00
Makefile [media] dvb-core: move dvb_filter out of the DVB core 2016-10-21 08:44:08 -02:00