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  1. 23 8月, 2013 1 次提交
  3. 04 6月, 2013 1 次提交
  5. 19 2月, 2013 1 次提交
  7. 16 1月, 2013 1 次提交
  9. 17 8月, 2012 1 次提交
  11. 14 6月, 2012 1 次提交
    • N
      W1: split master mutex to avoid deadlocks. · b02f8bed
      由 NeilBrown 提交于 
      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: NNeilBrown <neilb@suse.de>
Acked-by: NEvgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b02f8bed
  13. 18 11月, 2011 1 次提交
    • M
      W1: w1_therm: release the bus during conversion on externally powered devices · 377195c4
      由 Maciej Szmigiero 提交于 
      w1_therm devices can either be bus powered or externally powered.

When device is bus powered during temperature conversion the bus
have to be left high to provide necessary power. Some masters also allow
strong power-up to be enabled in this case.
Naturally, no communication over bus can occur during that time.

However, if device has external power then there is no such restriction,
and host can talk to other devices during temperature conversion.

There is command which allows us to check how device is powered,
this patch uses it to release the bus on externally w1_therm powered devices
during temperature conversion.

Also, this changes uninterruptible sleeps there into interruptible ones to
avoid long uninterruptible sleep if w1 subsystem happens to grab bus for
scan during w1_therm_read().
Signed-off-by: NMaciej Szmigiero <mhej@o2.pl>
Acked-by: NEvgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      377195c4
  15. 26 8月, 2011 1 次提交
  17. 27 7月, 2011 1 次提交
  19. 25 4月, 2010 1 次提交
  21. 12 2月, 2009 1 次提交
  23. 17 10月, 2008 3 次提交
  25. 07 2月, 2008 1 次提交
    • D
      W1: w1_therm.c standardize units to millidegrees C · 7129b126
      由 David Fries 提交于 
      Standardize the temperature units to millidegrees C for the two sensor
conversion routines.  Previously the routines were,

w1_DS18B20_convert_temp degrees C
w1_DS18S20_convert_temp millidegrees C

Unfortunately this will break any program using the ds18b20 value as it
will now be 1000 times bigger.  Fortunately there can't be that many users
out there, or some of these bugs will have been fixed by now, such as the
negative C error (see previous patch) that makes me think the ds18b20 is
the better choice to change because of the current bugs.
Signed-off-by: NDavid Fries <david@fries.net>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      7129b126
  27. 23 1月, 2008 2 次提交
    • D
      W1: w1_therm.c is flagging 0C etc as invalid · 80c002dd
      由 David Fries 提交于 
      The extra rom[0] check is flagging valid temperatures as invalid when
there is already a CRC data transmission check.

w1_therm_read_bin()
	if (rom[8] == crc && rom[0])
		verdict = 1;

Requiring rom[0] to be non-zero will flag as invalid temperature
conversions when the low byte is zero, specifically the temperatures 0C,
16C, 32C, 48C, -16C, -32C, and -48C.

The CRC check is produced on the device for the previous 8 bytes and is
required to ensure the data integrity in transmission.  I don't see why the
extra check for rom[0] being non-zero is in there.  Evgeniy Polyakov didn't
know either.  Just for a check I unplugged the sensor, executed a
temperature conversion, and read the results.  The read was all ff's, which
also failed the CRC, so it doesn't need to protect against a disconnected
sensor.

I have more extensive patches in the work, but these two trivial ones will
do for today.  I would like to hear from people who use the ds2490 USB to
one wire dongle.  1 if you would be willing to test the patches as I
currently only have the one sensor on a short parisite powered wire, 2 if
there is any cheap sources for the ds2490.
Signed-off-by: NDavid Fries <david@fries.net>
Acked-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      80c002dd
    • D
      W1: w1_therm.c ds18b20 decode freezing temperatures correctly · 941ed3b5
      由 David Fries 提交于 
      Correct the decoding of negative C temperatures.  The code did a binary OR
of two bytes to make a 16 bit value, but assignd it to an integer.  This
caused the value to not be sign extended and to loose that it was a
negative number in the assignment.

Before the patch (in my freezer),
	w1_slave
	ed fe 4b 46 7f ff 03 10 e4 : crc=e4 YES
	ed fe 4b 46 7f ff 03 10 e4 t=4078
With the patch,
	e3 fe 4b 46 7f ff 0d 10 81 : crc=81 YES
	e3 fe 4b 46 7f ff 0d 10 81 t=-17
Signed-off-by: NDavid Fries <david@fries.net>
Acked-by: NEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      941ed3b5
  29. 12 7月, 2007 2 次提交
    • Z
      sysfs: add parameter "struct bin_attribute *" in .read/.write methods for sysfs binary attributes · 91a69029
      由 Zhang Rui 提交于 
      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: NZhang Rui <rui.zhang@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      91a69029
    • T
      sysfs: kill unnecessary attribute->owner · 7b595756
      由 Tejun Heo 提交于 
      sysfs is now completely out of driver/module lifetime game.  After
deletion, a sysfs node doesn't access anything outside sysfs proper,
so there's no reason to hold onto the attribute owners.  Note that
often the wrong modules were accounted for as owners leading to
accessing removed modules.

This patch kills now unnecessary attribute->owner.  Note that with
this change, userland holding a sysfs node does not prevent the
backing module from being unloaded.

For more info regarding lifetime rule cleanup, please read the
following message.

  http://article.gmane.org/gmane.linux.kernel/510293

(tweaked by Greg to not delete the field just yet, to make it easier to
merge things properly.)
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      7b595756
  31. 29 6月, 2007 1 次提交
  33. 13 2月, 2007 1 次提交
  35. 04 12月, 2006 1 次提交
  37. 23 6月, 2006 2 次提交
  39. 24 3月, 2006 1 次提交
  41. 09 9月, 2005 3 次提交
  43. 22 6月, 2005 4 次提交
  45. 21 6月, 2005 1 次提交
  47. 17 4月, 2005 1 次提交
    • L
      Linux-2.6.12-rc2 · 1da177e4
      由 Linus Torvalds 提交于 
      Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
      1da177e4