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2014-06-20w1: use pr_* instead of printkFjodor Schelichow1-6/+4
This patch replaces all calls to the "printk" function within the main "w1" directory by calls to the appropriate "pr_*" function thus addressing the following warning generated by the checkpatch script: WARNING: Prefer [subsystem eg: netdev]_err([subsystem]dev, ... then dev_err(dev, ... then pr_err(... to printk(KERN_ERR ... Signed-off-by: Fjodor Schelichow <fjodor.schelichow@hotmail.com> Signed-off-by: Roman Sommer <romsom2@yahoo.de> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-28w1: do not unlock unheld list_mutex in __w1_remove_master_device()Alexey Khoroshilov1-0/+2
w1_process_callbacks() expects to be called with dev->list_mutex held, but it is the fact only in w1_process(). __w1_remove_master_device() calls w1_process_callbacks() after it releases list_mutex. The patch fixes __w1_remove_master_device() to acquire list_mutex for w1_process_callbacks(). Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Acked-by: David Fries <david@fries.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Cc: stable <stable@vger.kernel.org> # 3.15 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-17w1: avoid recursive device_addDavid Fries1-26/+6
__w1_attach_slave_device calls device_add which calls w1_bus_notify which calls the w1_bq27000 slave driver, which calls platform_device_add and device_add and deadlocks on getting &(&priv->bus_notifier)->rwsem as it is still held in the previous device_add. This avoids the problem by processing the family add/remove outside of the slave device_add call. Commit 47eba33a0997fc7362a introduced this deadlock and added a KOBJ_ADD, as the add was already reported in device_register two add events were being sent. This change suppresses the device_register add so that any slave device sysfs entries are setup before the add goes out. Belisko Marek reported this change fixed the deadlock he was seeing on ARM device tree, while testing on my x86-64 system never saw the deadlock. Reported-by: Belisko Marek <marek.belisko@gmail.com> Signed-off-by: David Fries <David@Fries.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-15w1: small type cleanup in sysfsDan Carpenter1-2/+2
On 64 bit systems, a large value for "long tmp" is truncated when assigning to "int md->max_slave_count" so we still end up with a value less than one despite the "tmp < 1" check. This is more of a problem for static checkers than a real life issue, but it's simple enough to fix. Acked-by: David Fries <david@fries.net> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-08w1: format for DocBook and fixesDavid Fries1-4/+26
Switch the code documentation format style to DocBook format, enable DocBook documentation generation, and fix some comments. Signed-off-by: David Fries <David@Fries.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-08w1: process w1 netlink commands in w1_process threadDavid Fries1-52/+128
Netlink is a socket interface and is expected to be asynchronous. Clients can now make w1 requests without blocking by making use of the w1_master thread to process netlink commands which was previously only used for doing an automatic bus search. Signed-off-by: David Fries <David@Fries.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-08w1: new netlink commands, add/remove/list slavesDavid Fries1-4/+2
Introduce new commands to add, remove, and list slave devices through the netlink interface. This can be useful to skip the search on a static network. They could previously only be added or removed through automatic search or sysfs, and this allows a program to only use netlink. Only allocate memory when needed, so move kzalloc into w1_get_slaves where it was used. Signed-off-by: David Fries <David@Fries.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-08w1: continue slave search where previous left offDavid Fries1-3/+15
Search will detect at most max_slave_count devices per run, if there are more pick up the next search where the previous left off. Signed-off-by: David Fries <David@Fries.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-08w1: increase w1_max_slave_count, allow write accessDavid Fries1-2/+28
w1_max_slave_count is only used to abort the search early or take a fast search (when 1), so there isn't any reason to not allow it to be updated through sysfs. Memory is not allocated based on the current value and 10 is a rather low base number, increasing to 64, and printing a message the first time the count is reached and there were more devices to discover to let the user know why not all the devices were found. Signed-off-by: David Fries <David@Fries.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-08w1: Only wake up the search process if it is going to be searchingDavid Fries1-1/+3
It's valid to set the search count to 0 to stop searching, so don't wake up the search thread to not search. Signed-off-by: David Fries <David@Fries.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-08w1: fixup search to support abort from netlinkDavid Fries1-2/+1
Before 63706172f33 "rework kthread_stop()" kthread_should_stop() always returned false when called from a non-kthread task, after it would oops as a non-kthread didn't have that structure and netlink was calling search from a thread which wasn't a kthread. 9d1817cab2f030 "w1: fix oops when w1_search is called from netlink connector", modified the code to avoid calling kthread_stop from a netlink thread. Introduce a w1_master flag and bit W1_ABORT_SEARCH to identify abort to cleanly support both kthread and netlink search abort. A search can take seconds to run, so it is important to abort early if the hardware is removed in the middle of a search. Signed-off-by: David Fries <David@Fries.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Cc: Marcin Jurkowski <marcin1j@gmail.com> Cc: Josh Boyer <jwboyer@gmail.com> Cc: Sven Geggus <lists@fuchsschwanzdomain.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-13drivers: w1: make w1_slave::flags long to avoid memory corruptionMichal Nazarewicz1-5/+5
On architectures where long is more then 32 bits, modifying a 32-bit field with set_bit (and other atomic bit operations) may cause bytes following the field to by modified. Because the endianness of the bits within a field is the native endianness of the CPU[1], on big-endian machines, bit number zero is in the last byte of the field. Therefore, `set_bit(0, ptr)' on a 64-bit big-endian machine is roughly equivalent to `((char *)ptr)[7] |= 1', and since w1 driver uses a 32-bit field for holding the flags, this causes bytes beyond the field to be modified. [1] From Documentation/atomic_ops.txt: Native atomic bit operations are defined to operate on objects aligned to the size of an "unsigned long" C data type, and are least of that size. The endianness of the bits within each "unsigned long" are the native endianness of the cpu. Signed-off-by: Michal Nazarewicz <mina86@mina86.com> Cc: Evgeniy Polyakov <zbr@ioremap.net> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-07w1 - call request_module with w1 master mutex unlockedHans-Frieder Vogt1-0/+3
request_module for w1 slave modules needs to be called with the w1 master mutex unlocked. Because w1_attach_slave_device gets always(?) called with mutex locked, we need to temporarily unlock the w1 master mutex for the loading of the w1 slave module. Signed-off by: Hans-Frieder Vogt <hfvogt@gmx.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Cc: stable <stable@vger.kernel.org> # 3.11+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-07w1 - fix fops in w1_bus_notifyHans-Frieder Vogt1-0/+3
Introduce a check to make sure that fops are only called if they have been defined by the slave module. Without this check modules like w1_smem cause a NULL pointer dereference bug. Signed-off by: Hans-Frieder Vogt <hfvogt@gmx.net> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Cc: stable <stable@vger.kernel.org> # 3.11+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-12drivers/w1/w1.c: replace strict_strtol() with kstrtol()Jingoo Han1-4/+8
The usage of strict_strtol() is not preferred, because strict_strtol() is obsolete. Thus, kstrtol() should be used. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-22w1: add attribute groups to struct w1_family_opsGreg Kroah-Hartman1-32/+41
This lets w1 slave drivers declare an attribute group, and not have to create/destroy sysfs files directly. All w1 slave drivers will be fixed to use this field up in follow-on patches to this one. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-22w1: use default attribute groups for w1 slave devicesGreg Kroah-Hartman1-27/+11
As we have 2 sysfs files for the w1 slave devices, let the driver core create / destroy them automatically by setting the default attribute group for them, saving code and housekeeping logic. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-22w1: remove race with sysfs file creationGreg Kroah-Hartman1-38/+73
W1 slave sysfs files are created _after_ userspace is notified that the device has been added to the system. Fix that race by moving the creation/remove of the files to the bus notifier that is there for doing this type of thing. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-04w1: add family based automatic module loadingAlexander Stein1-0/+2
This patch allows the 1-wire bus to autoload the corresponding module for each slave being attached. This works similar to bluetooth protocols. Signed-off-by: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-13w1: fix oops when w1_search is called from netlink connectorMarcin Jurkowski1-1/+2
On Sat, Mar 02, 2013 at 10:45:10AM +0100, Sven Geggus wrote: > This is the bad commit I found doing git bisect: > 04f482faf50535229a5a5c8d629cf963899f857c is the first bad commit > commit 04f482faf50535229a5a5c8d629cf963899f857c > Author: Patrick McHardy <kaber@trash.net> > Date: Mon Mar 28 08:39:36 2011 +0000 Good job. I was too lazy to bisect for bad commit;) Reading the code I found problematic kthread_should_stop call from netlink connector which causes the oops. After applying a patch, I've been testing owfs+w1 setup for nearly two days and it seems to work very reliable (no hangs, no memleaks etc). More detailed description and possible fix is given below: Function w1_search can be called from either kthread or netlink callback. While the former works fine, the latter causes oops due to kthread_should_stop invocation. This patch adds a check if w1_search is serving netlink command, skipping kthread_should_stop invocation if so. Signed-off-by: Marcin Jurkowski <marcin1j@gmail.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Cc: Josh Boyer <jwboyer@gmail.com> Tested-by: Sven Geggus <lists@fuchsschwanzdomain.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable <stable@vger.kernel.org> # 3.0+
2012-11-22w1: remove CONFIG_HOTPLUG ifdefsBill Pemberton1-7/+0
Remove conditional code based on CONFIG_HOTPLUG being false. It's always on now in preparation of it going away as an option. Signed-off-by: Bill Pemberton <wfp5p@virginia.edu> Cc: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-14W1: split master mutex to avoid deadlocks.NeilBrown1-1/+8
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>
2012-06-14Revert "w1: introduce a slave mutex for serializing IO"Greg Kroah-Hartman1-1/+0
This reverts commit 59d4467be405316916a4087d5b02d99196eeef04. Turns out it was the wrong version, will apply the correct version after this. Reported-by: NeilBrown <neilb@suse.de> Cc: Evgeniy Polyakov <zbr@ioremap.net> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13w1: cleanup w1_ueventDevendra Naga1-8/+6
There were some return statements around in the w1_uevent, used goto to cleanup those return statements with the help of err variable, and also removed a semi colon at the end of the w1_uevent's closing brace. Signed-off-by: Devendra Naga <devendra.aaru@gmail.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13w1: introduce a slave mutex for serializing IONeilBrown1-0/+1
w1 devices need a mutex to serial IO. Most use master->mutex. However that is used for other purposes and they can conflict. In particular master->mutex is held while w1_attach_slave_device is called. For bq27000, this registers a 'powersupply' device which tries to read the current status. The attempt to read will cause a deadlock on master->mutex. So create a new per-slave mutex and use that for serializing IO for bq27000. Signed-off-by: NeilBrown <neilb@suse.de> Cc: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-10w1: fix slave driver registration error messageDmitry Artamonow1-1/+1
W1 core prints "Failed to register master driver" if error happens on registering SLAVE driver. Fix it. Signed-off-by: Dmitry Artamonow <mad_soft@inbox.ru> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2011-12-10w1: add fast search for single slave busEvgeniy Polyakov1-0/+10
This enables a much more efficient way of device searching. It uses the 1-wire read-rom operation which allows the direct reading of the slave address. BUT this works only with exactly one slave on the bus. Signed-off-by: Hubert Feurstein <h.feurstein@gmail.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> index c374978..9761950 100644 Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-26MAINTAINERS: Evgeniy has movedEvgeniy Polyakov1-2/+2
Signed-off-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-27atomic: use <linux/atomic.h>Arun Sharma1-1/+1
This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-27w1: have netlink search update kernel listDavid Fries1-3/+9
Reorganize so the netlink connector one wire search command will update the kernel list of detected slave devices. Otherwise, a newly detected device is unusable because unless it's in the kernel list of known devices any commands will result in ENODEV status. Signed-off-by: David Fries <David@Fries.net> Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-28w1: don't allow arbitrary users to remove w1 devicesBrian Swetland1-4/+4
The search/pullup/add/remove device attributes were 0666 which would allow arbitrary users to affect the 1 wire bus. Change to 0664 to prevent that. I found this patch in the Android tree, apparently this has never been sent upstream so doing it now. Signed-off-by: Brian Swetland <swetland@google.com> Signed-off-by: Linus Walleij <linus.walleij@stericsson.com> Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru> 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 Wright1-2/+2
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>
2010-02-05w1: add __init/__exit macros to w1.cPeter Huewe1-2/+2
Trivial patch which adds the __init/__exit macros to the module_init/ module_exit functions of drivers/w1/w1.c Signed-off-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-01-06w1: struct device - replace bus_id with dev_name(), dev_set_name()Kay Sievers1-10/+9
CC: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-16W1: w1.c s/printk/dev_dbg/David Fries1-3/+3
s/printk/dev_dbg/ Signed-off-by: David Fries <david@fries.net> Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16W1: w1_slave_read_id read bug, use device_attributeDavid Fries1-25/+10
Fix bug reading the id sysfs file. If less than the full 8 bytes were read, the next read would start at the first byte instead of continuing. It needed the offset added to memcpy, or the better solution was to replace it with the device attribute instead of bin attribute. Signed-off-by: David Fries <david@fries.net> Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16W1: recode w1_slave_found logicDavid Fries1-20/+6
Simplified the logic in w1_slave_found by using the new w1_attach_slave_device function to find a slave and mark it as active or add the device if the crc checks. Signed-off-by: David Fries <david@fries.net> Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16W1: be able to manually add and remove slavesDavid Fries1-1/+137
sysfs entries were added to manually add and remove slave devices. This is useful if the automatic bus searching is disabled, and the device ids are already known. [akpm@linux-foundation.org: fix printk types] Signed-off-by: David Fries <david@fries.net> Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16W1: feature, enable hardware strong pullupDavid Fries1-1/+39
Add a strong pullup option to the w1 system. This supplies extra power for parasite powered devices. There is a w1_master_pullup sysfs entry and enable_pullup module parameter to enable or disable the strong pullup. The one wire bus requires at a minimum one wire and ground. The common wire is used for sending and receiving data as well as supplying power to devices that are parasite powered of which temperature sensors can be one example. The bus must be idle and left high while a temperature conversion is in progress, in addition the normal pullup resister on larger networks or even higher temperatures might not supply enough power. The pullup resister can't provide too much pullup current, because devices need to pull the bus down to write a value. This enables the strong pullup for supported hardware, which can supply more current when requested. Unsupported hardware will just delay with the bus high. The hardware USB 2490 one wire bus master has a bit on some commands which will enable the strong pullup as soon as the command finishes executing. To use strong pullup, call the new w1_next_pullup function to register the duration. The next write command will call set_pullup before sending the data, and reset the duration to zero once it returns. Switched from simple_strtol to strict_strtol. Signed-off-by: David Fries <david@fries.net> Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16W1: w1_process, block or sleepDavid Fries1-3/+17
The w1_process thread's sleeping and termination has been modified. msleep_interruptible was replaced by schedule_timeout and schedule to allow for kthread_stop and wake_up_process to interrupt the sleep and the unbounded sleeping when a bus search is disabled. The W1_MASTER_NEED_EXIT and flags variable were removed as they were redundant with kthread_should_stop and kthread_stop. If w1_process is sleeping, requesting a search will immediately wake it up rather than waiting for the end of msleep_interruptible previously. Signed-off-by: David Fries <david@fries.net> Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16W1: don't delay search startDavid Fries1-13/+6
Move the creation of the w1_process thread to after the device has been initialized. This way w1_process doesn't have to check to see if it has been initialized and the bus search can proceed without sleeping. That also eliminates two checks in the w1_process loop. The sleep now happens at the end of the loop not the beginning. Also added a comment for why the atomic_set was 2. Signed-off-by: David Fries <david@fries.net> Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16W1: abort search early on on exitDavid Fries1-0/+5
Early abort if the master driver or the hardware goes away in the middle of a bus search operation. The alternative is to spam the print buffer up to 64*64 times with read errors in the case of USB. Signed-off-by: David Fries <david@fries.net> Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16W1: fix deadlocks and remove w1_control_threadDavid Fries1-112/+34
w1_control_thread was removed which would wake up every second and process newly registered family codes and complete some final cleanup for a removed master. Those routines were moved to the threads that were previously requesting those operations. A new function w1_reconnect_slaves takes care of reconnecting existing slave devices when a new family code is registered or removed. The removal case was missing and would cause a deadlock waiting for the family code reference count to decrease, which will now happen. A problem with registering a family code was fixed. A slave device would be unattached if it wasn't yet claimed, then attached at the end of the list, two unclaimed slaves would cause an infinite loop. The struct w1_bus_master.search now takes a pointer to the struct w1_master device to avoid searching for it, which would have caused a lock ordering deadlock with the removal of w1_control_thread. Signed-off-by: David Fries <david@fries.net> Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06w1: remove unused and confusing variable.Evgeniy Polyakov1-4/+0
Remvoe variable which actually is not used (except assigning it a value) and confusing break out of the family checking loop. Found by Harry Mason. Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Cc: Harry J Mason <hjm03r@ecs.soton.ac.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-14w1: decrement slave counter only in ->release() callbackEvgeniy Polyakov1-4/+2
Decrement the slave counter only in ->release() callback instead of both in ->release() and w1 control. Patch is based on debug work and preliminary patch made by Henri Laakso. Henri noticed in debug that this counter becomes negative after w1 slave device is physically removed. Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Cc: Henri Laakso <henri.laakso@wapice.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-13Driver core: change add_uevent_var to use a structKay Sievers1-12/+7
This changes the uevent buffer functions to use a struct instead of a long list of parameters. It does no longer require the caller to do the proper buffer termination and size accounting, which is currently wrong in some places. It fixes a known bug where parts of the uevent environment are overwritten because of wrong index calculations. Many thanks to Mathieu Desnoyers for finding bugs and improving the error handling. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-09-25missing null termination in one wire ueventStephen Hemminger1-0/+1
Need to null terminate environment. Found by inspection while looking for similar problems to platform uevent bug Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19some kmalloc/memset ->kzalloc (tree wide)Yoann Padioleau1-2/+1
Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc). Here is a short excerpt of the semantic patch performing this transformation: @@ type T2; expression x; identifier f,fld; expression E; expression E1,E2; expression e1,e2,e3,y; statement S; @@ x = - kmalloc + kzalloc (E1,E2) ... when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\) - memset((T2)x,0,E1); @@ expression E1,E2,E3; @@ - kzalloc(E1 * E2,E3) + kcalloc(E1,E2,E3) [akpm@linux-foundation.org: get kcalloc args the right way around] Signed-off-by: Yoann Padioleau <padator@wanadoo.fr> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Acked-by: Russell King <rmk@arm.linux.org.uk> Cc: Bryan Wu <bryan.wu@analog.com> Acked-by: Jiri Slaby <jirislaby@gmail.com> Cc: Dave Airlie <airlied@linux.ie> Acked-by: Roland Dreier <rolandd@cisco.com> Cc: Jiri Kosina <jkosina@suse.cz> Acked-by: Dmitry Torokhov <dtor@mail.ru> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org> Acked-by: Pierre Ossman <drzeus-list@drzeus.cx> Cc: Jeff Garzik <jeff@garzik.org> Cc: "David S. Miller" <davem@davemloft.net> Acked-by: Greg KH <greg@kroah.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17Freezer: make kernel threads nonfreezable by defaultRafael J. Wysocki1-0/+1
Currently, the freezer treats all tasks as freezable, except for the kernel threads that explicitly set the PF_NOFREEZE flag for themselves. This approach is problematic, since it requires every kernel thread to either set PF_NOFREEZE explicitly, or call try_to_freeze(), even if it doesn't care for the freezing of tasks at all. It seems better to only require the kernel threads that want to or need to be frozen to use some freezer-related code and to remove any freezer-related code from the other (nonfreezable) kernel threads, which is done in this patch. The patch causes all kernel threads to be nonfreezable by default (ie. to have PF_NOFREEZE set by default) and introduces the set_freezable() function that should be called by the freezable kernel threads in order to unset PF_NOFREEZE. It also makes all of the currently freezable kernel threads call set_freezable(), so it shouldn't cause any (intentional) change of behaviour to appear. Additionally, it updates documentation to describe the freezing of tasks more accurately. [akpm@linux-foundation.org: build fixes] Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Nigel Cunningham <nigel@nigel.suspend2.net> Cc: Pavel Machek <pavel@ucw.cz> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Gautham R Shenoy <ego@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-12sysfs: add parameter "struct bin_attribute *" in .read/.write methods for ↵Zhang Rui1-3/+9
sysfs binary attributes Well, first of all, I don't want to change so many files either. What I do: Adding a new parameter "struct bin_attribute *" in the .read/.write methods for the sysfs binary attributes. In fact, only the four lines change in fs/sysfs/bin.c and include/linux/sysfs.h do the real work. But I have to update all the files that use binary attributes to make them compatible with the new .read and .write methods. I'm not sure if I missed any. :( Why I do this: For a sysfs attribute, we can get a pointer pointing to the struct attribute in the .show/.store method, while we can't do this for the binary attributes. I don't know why this is different, but this does make it not so handy to use the binary attributes as the regular ones. So I think this patch is reasonable. :) Who benefits from it: The patch that exposes ACPI tables in sysfs requires such an improvement. All the table binary attributes share the same .read method. Parameter "struct bin_attribute *" is used to get the table signature and instance number which are used to distinguish different ACPI table binary attributes. Without this parameter, we need to offer different .read methods for different ACPI table binary attributes. This is impossible as there are various ACPI tables on different platforms, and we don't know what they are until they are loaded. Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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