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path: root/drivers/w1/slaves/w1_ds2760.c
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2012-06-13W1: split master mutex to avoid deadlocks.NeilBrown
The 'mutex' in struct w1_master is use for two very different purposes. Firstly it protects various data structures such as the list of all slaves. Secondly it protects the w1 buss against concurrent accesses. This can lead to deadlocks when the ->probe code called while adding a slave needs to talk on the bus, as is the case for power_supply devices. ds2780 and ds2781 drivers contain a work around to track which process hold the lock simply to avoid this deadlock. bq27000 doesn't have that work around and so deadlocks. There are other possible deadlocks involving sysfs. When removing a device the sysfs s_active lock is held, so the lock that protects the slave list must take precedence over s_active. However when access power_supply attributes via sysfs, the s_active lock must take precedence over the lock that protects accesses to the bus. So to avoid deadlocks between w1 slaves and sysfs, these must be two separate locks. Making them separate means that the work around in ds2780 and ds2781 can be removed. So this patch: - adds a new mutex: "bus_mutex" which serialises access to the bus. - takes in mutex in w1_search and ds1wm_search while they access the bus for searching. The mutex is dropped before calling the callback which adds the slave. - changes all slaves to use bus_mutex instead of mutex to protect access to the bus - removes w1_ds2790_io_nolock and w1_ds2781_io_nolock, and the related code from drivers/power/ds278[01]_battery.c which calls them. Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2011-11-02w1: ds2760 and ds2780, use ida for id and ida_simple_get() to get itJonathan Cameron
Straightforward. As an aside, the ida_init calls are not needed as far as I can see needed. (DEFINE_IDA does the same already). Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk> Cc: Evgeniy Polyakov <zbr@ioremap.net> Acked-by: Clifton Barnes <cabarnes@indesign-llc.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-21sysfs: add struct file* to bin_attr callbacksChris Wright
This allows bin_attr->read,write,mmap callbacks to check file specific data (such as inode owner) as part of any privilege validation. Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-06-08w1: ds2760: add support for EEPROM read and writeDaniel Mack
In order to modify the DS2762's status registers and to add support for sleep mode, there is need for functions to write the internal EEPROM. Signed-off-by: Daniel Mack <daniel@caiaq.de> Acked-by: Matt Reimer <mreimer@vpop.net> Acked-by: Szabolcs Gyurko <szabolcs.gyurko@tlt.hu> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
2008-10-20x86: sysfs: kill owner field from attributeParag Warudkar
Tejun's commit 7b595756ec1f49e0049a9e01a1298d53a7faaa15 made sysfs attribute->owner unnecessary. But the field was left in the structure to ease the merge. It's been over a year since that change and it is now time to start killing attribute->owner along with its users - one arch at a time! This patch is attempt #1 to get rid of attribute->owner only for CONFIG_X86_64 or CONFIG_X86_32 . We will deal with other arches later on as and when possible - avr32 will be the next since that is something I can test. Compile (make allyesconfig / make allmodconfig / custom config) and boot tested. akpm: the idea is that we put the declaration of sttribute.owner inside `#ifndef CONFIG_X86'. But that proved to be too ambitious for now because new usages kept on turning up in subsystem trees. [akpm: remove the ifdef for now] Signed-off-by: Parag Warudkar <parag.lkml@gmail.com> Cc: Greg KH <greg@kroah.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Tejun Heo <htejun@gmail.com> Cc: Len Brown <lenb@kernel.org> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jean Delvare <khali@linux-fr.org> Cc: Roland Dreier <rolandd@cisco.com> Cc: David Brownell <david-b@pacbell.net> 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>
2007-07-15git-battery vs git-acpiAndrew Morton
drivers/w1/slaves/w1_ds2760.c:85: warning: initialization from incompatible pointer type The ACPI guys changed the bin_attr APIs (commit 91a6902958f052358899f58683d44e36228d85c2) Cc: Anton Vorontsov <cbou@mail.ru> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2007-07-15Power supply class and drivers: remove non obligatory return statementsAnton Vorontsov
Per Jeff Garzik request. Signed-off-by: Jeff Garzik <jeff@garzik.org> Signed-off-by: Anton Vorontsov <cbou@mail.ru>
2007-07-10[BATTERY] ds2760 W1 slaveAnton Vorontsov
This is W1 slave for ds2760 chip, found inside almost every HP iPaq and HTC PDAs/phones. Signed-off-by: Anton Vorontsov <cbou@mail.ru> Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: David Woodhouse <dwmw2@infradead.org>