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2008-04-30V4L/DVB(7767): Move tuners to common/tunersMauro Carvalho Chehab49-198/+248
There were several issues in the past, caused by the hybrid tuner design, since now, the same tuner can be used by drivers/media/dvb and drivers/media/video. Kconfig items were rearranged, to split V4L/DVB core from their drivers. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7766): saa7134: add another PCI ID for Beholder M6Igor Kuznetsov1-0/+6
Signed-off-by: Igor Kuznetsov <igk@igk.ru> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7765): Add support for Beholder BeholdTV H6Igor Kuznetsov3-0/+38
Signed-off-by: Igor Kuznetsov <igk@igk.ru> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7763): ivtv: add tuner support for the AverMedia M116Hans Verkuil3-12/+18
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7762): ivtv: fix tuner detection for PAL-N/NcHans Verkuil1-16/+18
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7761): ivtv: increase the DMA timeout from 100 to 300 msHans Verkuil1-2/+2
When there is a lot of DMA traffic this timeout might sometimes be too low. Increase it to be on the safe side. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7759): ivtv: increase version number to 1.2.1Hans Verkuil1-1/+1
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7758): ivtv: fix oops when itv->speed == 0 and VIDEO_CMD_PLAY is calledHans Verkuil1-10/+21
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7757): ivtv: add autodetect for the AVermedia M104 cardHans Verkuil3-1/+39
Note that this card is only detected and not yet working. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7756): ivtv: use strlcpy instead of strcpyHans Verkuil4-13/+15
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7755): ivtv: add support for card comments and detected but ↵Hans Verkuil3-0/+10
unsupported cards Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7754): ivtv: change initialization order to fix an oops when device ↵Hans Verkuil1-17/+16
registration failed Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7753): saa7134: fix tuner setupMauro Carvalho Chehab2-143/+117
Tuner setup were happening during i2c attach callback. This means that it would happen on two conditions: 1) if tuner module weren't load, it will happen at request_module("tuner"); 2) if tuner is not compiled as a module, or it is already loaded (for example, on setups with more than one tuner), it will happen when saa7134 registers I2C bus. Due to that, if tuner were loaded, tuner setup will happen _before_ reading the proper values at tuner eeprom. Since set_addr refuses to change for a tuner that were previously defined (except if the tuner_addr is set), this were making eeprom tuner detection useless. This patch removes tuner type setup from saa7134-i2c, moving it to the proper place, after taking eeprom into account. Reviewed-by: Hermann Pitton <hermann-pitton@arcor.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7752): tuner-core: add a missing \n after a debug printkMauro Carvalho Chehab1-1/+3
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-30V4L/DVB (7749): cx88: fix tuner setupMauro Carvalho Chehab2-36/+44
Tuner setup were happening during i2c attach callback. This means that it would happen on two conditions: 1) if tuner module weren't load, it will happen at request_module("tuner"); 2) if tuner is not compiled as a module, or it is already loaded (for example, on setups with more than one tuner), it will happen when cx88 registers I2C bus. Due to that, if tuner were loaded, tuner setup will happen _before_ reading the proper values at tuner eeprom. Since set_addr refuses to change for a tuner that were previously defined (except if the tuner_addr is set), this were making eeprom tuner detection useless. This patch removes tuner type setup from cx88-i2c, moving it to the proper place, after taking eeprom into account. Reviewed-by: Gert Vervoort <gert.vervoort@hccnet.nl> Reviewed-by: Ian Pickworth <ian@pickworth.me.uk> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-29drivers: use non-racy method for proc entries creation (2)Denis V. Lunev1-4/+3
Use proc_create()/proc_create_data() to make sure that ->proc_fops and ->data be setup before gluing PDE to main tree. Signed-off-by: Denis V. Lunev <den@openvz.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Peter Osterlund <petero2@telia.com> Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> Cc: Dmitry Torokhov <dtor@mail.ru> Cc: Neil Brown <neilb@suse.de> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29media: fix integer as NULL pointer warningsHarvey Harrison10-13/+16
drivers/media/video/v4l2-common.c:719:16: warning: Using plain integer as NULL pointer drivers/media/video/au0828/au0828-dvb.c:122:19: warning: Using plain integer as NULL pointer drivers/media/video/ivtv/ivtv-yuv.c:1101:22: warning: Using plain integer as NULL pointer drivers/media/video/ivtv/ivtv-yuv.c:1102:23: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-audio.c:78:39: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-video-v4l.c:84:39: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-v4l2.c:1264:9: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-context.c:197:28: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-cx2584x-v4l.c:126:39: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-dvb.c:133:32: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-dvb.c:145:31: warning: Using plain integer as NULL pointer drivers/media/video/pvrusb2/pvrusb2-dvb.c:177:55: warning: Using plain integer as NULL pointer drivers/media/video/videobuf-core.c:100:9: warning: Using plain integer as NULL pointer Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28mm: remove nopageNick Piggin1-1/+1
Nothing in the tree uses nopage any more. Remove support for it in the core mm code and documentation (and a few stray references to it in comments). Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-26V4L/DVB (7751): ir-kbd-i2c: Save a temporary memory allocation in ir_probeJean Delvare1-12/+9
Using i2c_transfer instead of i2c_master_recv in ir_probe saves a temporary memory allocation. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26V4L/DVB (7750): au0828/ cleanups and fixesAdrian Bunk5-33/+10
This patch contains the following cleanups and fixes: - "debug" is definitely not a good name for a global variable, renamed it to "au0828_debug" this fixes a compile error with some kernel configurations - since the module parameter is int the variable shouldn't be unsigned - remove the {usb,bridge,i2c}_debug module parameters since they are already covered by the "debug" module parameter - remove the unused au0828_bcount - make the needlessly global i2c_scan static - make the needlessly global dvb_register() static Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26V4L/DVB (7748): tuner-core: some adjustments at tuner logs, if debug enabledMauro Carvalho Chehab1-46/+46
set_addr log were almost useless: discarded SET_TYPE_ADDR commands weren't reported. This patch changed set_addr printk to print a message only if set_addr is wrong. It also fix printk at set_type, since, if an attach were failing, nothing were reported. With the current code, working or not, a call to set_addr will produce a debug printk. also, set_type() were producing a false error message on tuner_xc2028, since it were requesting for setting a frequency on a place where firmware name weren't set yet. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26V4L/DVB (7746): pvrusb2: make signed one-bit bitfields unsignedHarvey Harrison1-11/+11
Single-bit signed bitfields can only take 0/-1 rather than 0/1 as the drivers seems to assume...add unsigned. Noticed by sparse: drivers/media/video/pvrusb2/pvrusb2-devattr.h:107:34: error: dubious one-bit signed bitfield drivers/media/video/pvrusb2/pvrusb2-devattr.h:114:37: error: dubious one-bit signed bitfield drivers/media/video/pvrusb2/pvrusb2-devattr.h:117:30: error: dubious one-bit signed bitfield drivers/media/video/pvrusb2/pvrusb2-devattr.h:120:23: error: dubious one-bit signed bitfield drivers/media/video/pvrusb2/pvrusb2-devattr.h:124:24: error: dubious one-bit signed bitfield drivers/media/video/pvrusb2/pvrusb2-devattr.h:128:23: error: dubious one-bit signed bitfield drivers/media/video/pvrusb2/pvrusb2-devattr.h:138:36: error: dubious one-bit signed bitfield drivers/media/video/pvrusb2/pvrusb2-devattr.h:143:24: error: dubious one-bit signed bitfield drivers/media/video/pvrusb2/pvrusb2-devattr.h:144:28: error: dubious one-bit signed bitfield drivers/media/video/pvrusb2/pvrusb2-devattr.h:145:26: error: dubious one-bit signed bitfield drivers/media/video/pvrusb2/pvrusb2-devattr.h:146:23: error: dubious one-bit signed bitfield Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26V4L/DVB (7744): pvrusb2-dvb: add atsc/qam support for Hauppauge pvrusb2 ↵Michael Krufky2-0/+29
model 751xx Signed-off-by: Michael Krufky <mkrufky@linuxtv.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26V4L/DVB (7742): cx88: Add support for the DViCO FusionHDTV_7_GOLD digital modesSteven Toth3-0/+34
The S5H1411 demodulator is now enabled. Signed-off-by: Steven Toth <stoth@hauppauge.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26V4L/DVB (7741): s5h1411: Adding support for this ATSC/QAM demodulatorSteven Toth4-0/+987
This adds full support for this demodulator. Signed-off-by: Steven Toth <stoth@hauppauge.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26V4L/DVB (7740): tuner-xc2028.c dubious !x & yHarvey Harrison1-1/+1
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26V4L/DVB (7739): mt312.h: dubious one-bit signed bitfieldHarvey Harrison1-1/+1
Make it unsigned (0/1) rather than signed (0/-1). Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26V4L/DVB (7735): Fix compilation for au0828Brandon Philips1-1/+1
Encountered this error when testing. Kernel: arch/x86/boot/bzImage is ready (#76) MODPOST 813 modules ERROR: "dvb_dmx_init" [drivers/media/video/au0828/au0828.ko] undefined! ERROR: "dvb_unregister_adapter" [drivers/media/video/au0828/au0828.ko] undefined! ERROR: "dvb_register_frontend" [drivers/media/video/au0828/au0828.ko] undefined! ERROR: "dvb_unregister_frontend" [drivers/media/video/au0828/au0828.ko] undefined! ERROR: "dvb_net_release" [drivers/media/video/au0828/au0828.ko] undefined! ERROR: "dvb_frontend_detach" [drivers/media/video/au0828/au0828.ko] undefined! ERROR: "dvb_dmxdev_release" [drivers/media/video/au0828/au0828.ko] undefined! ERROR: "dvb_net_init" [drivers/media/video/au0828/au0828.ko] undefined! ERROR: "dvb_dmx_release" [drivers/media/video/au0828/au0828.ko] undefined! ERROR: "dvb_dmx_swfilter_packets" [drivers/media/video/au0828/au0828.ko] undefined! ERROR: "dvb_register_adapter" [drivers/media/video/au0828/au0828.ko] undefined! ERROR: "dvb_dmxdev_init" [drivers/media/video/au0828/au0828.ko] undefined! WARNING: modpost: Found 9 section mismatch(es). To see full details build your kernel with: 'make CONFIG_DEBUG_SECTION_MISMATCH=y' make[1]: *** [__modpost] Error 1 make: *** [modules] Error 2 Signed-off-by: Brandon Philips <bphilips@suse.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26V4L/DVB (7734): em28xx: copy and paste error in em28xx_init_isocJanne Grunau1-1/+1
Fixes a copy and paste error in check of kzalloc return value. The check block was copied from the previous allocation but the variable wasn't exchanged. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26V4L/DVB (7733): blackbird_find_mailbox negative return ignored in ↵Roel Kluin1-2/+4
blackbird_initialize_codec() dev->mailbox is unsigned. so a negative return goes unnoticed Signed-off-by: Roel Kluin <12o3l@tiscali.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26V4L/DVB (7732): vivi: fix a warningMauro Carvalho Chehab1-1/+1
some gcc versions complain that fh is used without being defined. The error report is bogus. However, fixing it is trivial. Better to make gcc happy. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-26v4l/dvb: add statics to avoid multiple definitionsHarvey Harrison2-4/+4
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/v4l-dvbLinus Torvalds408-7330/+24793
* git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/v4l-dvb: (452 commits) V4L/DVB (7731): tuner-xc2028: fix signal strength calculus V4L/DVB (7730): tuner-xc2028: Fix SCODE load for MTS firmwares V4L/DVB (7729): Fix VIDIOCGAP corruption in ivtv V4L/DVB (7728): tea5761: bugzilla #10462: tea5761 autodetection code were broken V4L/DVB (7726): cx23885: Enable cx23417 support on the HVR1800 V4L/DVB (7725): cx23885: Add generic cx23417 hardware encoder support V4L/DVB (7723): pvrusb2: Clean up input selection list generation in V4L interface V4L/DVB (7722): pvrusb2: Implement FM radio support for Gotview USB2.0 DVD 2 V4L/DVB (7721): pvrusb2: Restructure cx23416 firmware loading to have a common exit point V4L/DVB (7720): pvrusb2: Fix bad error code on cx23416 firmware load failure V4L/DVB (7719): pvrusb2: Implement input selection enforcement V4L/DVB (7718): pvrusb2-dvb: update Kbuild selections V4L/DVB (7717): pvrusb2-dvb: add DVB-T support for Hauppauge pvrusb2 model 73xxx V4L/DVB (7716): pvrusb2: clean up global functions V4L/DVB (7715): pvrusb2: Clean out all use of __FUNCTION__ V4L/DVB (7714): pvrusb2: Fix hang on module removal V4L/DVB (7713): pvrusb2: Implement cleaner DVB kernel thread shutdown V4L/DVB (7712): pvrusb2: Close connect/disconnect race V4L/DVB (7711): pvrusb2: Fix race on module unload V4L/DVB (7710): pvrusb2: Implement critical digital streaming quirk for onair devices ...
2008-04-24V4L/DVB (7731): tuner-xc2028: fix signal strength calculusMauro Carvalho Chehab1-3/+10
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7730): tuner-xc2028: Fix SCODE load for MTS firmwaresMauro Carvalho Chehab1-1/+6
There are different tables for MTS firmwares. This should be taken into account while selecting the proper firmware. While at tuner-xc2028.h, improve some comments. Thanks to Edward J. Sheldrake <ejs1920@yahoo.co.uk> for helping to diagnose such troubles with PAL/I standard. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7729): Fix VIDIOCGAP corruption in ivtvAlan Cox1-1/+2
Frank Bennett reported that ivtv was causing skype to crash. With help from one of their developers he showed it was a kernel problem. VIDIOCGCAP copies a name into a fixed length buffer - ivtv uses names that are too long and does not truncate them so corrupts a few bytes of the app data area. Possibly the names also want trimming but for now this should fix the corruption case. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7728): tea5761: bugzilla #10462: tea5761 autodetection code were brokenMauro Carvalho Chehab2-8/+13
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7726): cx23885: Enable cx23417 support on the HVR1800Steven Toth4-2/+89
cx23885: Enable cx23417 support on the HVR1800 Signed-off-by: Steven Toth <stoth@hauppauge.com> Signed-off-by: Michael Krufky <mkrufky@linuxtv.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7725): cx23885: Add generic cx23417 hardware encoder supportSteven Toth4-31/+1921
cx23885: Add generic cx23417 hardware encoder support. Signed-off-by: Steven Toth <stoth@hauppauge.com> Signed-off-by: Michael Krufky <mkrufky@linuxtv.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7723): pvrusb2: Clean up input selection list generation in V4L ↵Mike Isely1-32/+37
interface Change how list of possible pvrusb2 inputs is generated to include only those interfaces that make sense for the interface instance. Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7722): pvrusb2: Implement FM radio support for Gotview USB2.0 DVD 2Mike Isely3-1/+31
Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7721): pvrusb2: Restructure cx23416 firmware loading to have a ↵Mike Isely1-4/+8
common exit point Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7720): pvrusb2: Fix bad error code on cx23416 firmware load failureMike Isely1-1/+1
Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7719): pvrusb2: Implement input selection enforcementMike Isely7-74/+246
In the pvrusb2 driver, different interfaces (e.g. V4L, DVB) have Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7718): pvrusb2-dvb: update Kbuild selectionsMichael Krufky1-0/+6
These changes are required with the addition of digital television support for the Hauppauge HVR1900 & HVR1950, the OnAir Creator and Sasem USB HDTV Signed-off-by: Michael Krufky <mkrufky@linuxtv.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7717): pvrusb2-dvb: add DVB-T support for Hauppauge pvrusb2 model 73xxxMichael Krufky1-4/+48
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7716): pvrusb2: clean up global functionsAdrian Bunk2-50/+1
This patch contains the following cleanups: - make the following needlessly global function static: - pvr2_hdw_set_cur_freq() - #if 0 the following unused global functions: - pvr2_hdw_get_state_name() - pvr2_hdw_get_debug_info_unlocked() - pvr2_hdw_get_debug_info_locked() Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7715): pvrusb2: Clean out all use of __FUNCTION__Mike Isely1-20/+29
Apparently the kernel developers no longer consider it proper etiquette to use __FUNCTION__; everyone must instead use __func__ (even though it breaks with older compilers). And worse still, actual effort is being expended to sweep this change throughout the kernel source tree. Don't these people have better things to do? So... Completely clean out all use of __FUNCTION__ from the pvrusb2 driver (it was just in the sysfs interface). I'm not going to use __func__ either. So there. Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7714): pvrusb2: Fix hang on module removalMike Isely1-1/+18
The pvrusb2 driver was getting had by this scenario: 1. Task A calls kthread_stop() for task B. 2. Before exiting, then Task B calls kthread_stop() for task C. The problem is, kthread_stop() wants to allocate an internal resource to itself (i.e. acquire a lock), which won't be released until kthread_stop() returns. But kthread_stop() won't return until task B is dead. But task B won't die until it finishes its call to kthread_stop() for task C, and that will block waiting on the resource already allocated inside task A. Deadlock. With the pvrusb2 driver, task A is the caller to pvr_exit(), task B is the control thread run inside of pvrusb2-context.c, and task C is any worker thread run inside of pvrusb2-hdw.c. This problem got introduced by the previous threading setup change, which was itself an attempt to fix a module tear-down race (which it actually did fix). The lesson here is that a task being waited on as part of a kthread_stop() simply cannot be allow to also issue a kthread_stop() - or we make sure not to issue the enclosing kthread_stop() until we know that the inner kthread_stop() has completed first. The solution for the pvrusb2 driver is some hackish code which changes the main control thread tear down into a two step process. This then makes it possible to delay issuing the kthread_stop() on the control thread until after we know that everything has been torn down first. (And yes, we really need that kthread_stop() because it's the only way to safely guarantee that a module-referencing kernel thread has safely returned back out of the module before we finally remove the module.) Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2008-04-24V4L/DVB (7713): pvrusb2: Implement cleaner DVB kernel thread shutdownMike Isely2-6/+1
Earlier fix to handle DVB feed thread aborts was overly-aggressive. We can take better advantage of what kthread_stop() can do. This change simplifies things. Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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