Commit graph

23 commits

Author SHA1 Message Date
David Fries
347ba8a588 W1: w1_therm fix user buffer overflow and cat
Fixed data reading bug by replacing binary attribute with device one.

Switching the sysfs read from bin_attribute to device_attribute.  The data
is far under PAGE_SIZE so the binary interface isn't required.  As the
device_attribute interface will make one call to w1_therm_read per file
open and buffer, the result is, the following problems go away.

buffer overflow:
	Execute a short read on w1_slave and w1_therm_read_bin would still
	return the full string size worth of data clobbering the user space
	buffer when it returned.  Switching to device_attribute avoids the
	buffer overflow problems.  With the snprintf formatted output dealing
	with short reads without doing a conversion per read would have
	been difficult.
bad behavior:
	`cat w1_slave` would cause two temperature conversions to take place.
	Previously the code assumed W1_SLAVE_DATA_SIZE would be returned with
	each read.  It would not return 0 unless the offset was less
	than W1_SLAVE_DATA_SIZE.  The result was the first read did a
	temperature conversion, filled the buffer and returned, the
	offset in the second read would be less than
	W1_SLAVE_DATA_SIZE and also fill the buffer and return, the
	third read would finnally have a big enough offset to return 0
	and cause cat to stop.  Now w1_therm_read will be called at
	most once per open.

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>
2008-10-16 11:21:50 -07:00
David Fries
6a158c0de7 W1: feature, enable hardware strong pullup
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>
2008-10-16 11:21:49 -07:00
David Fries
3c52e4e627 W1: w1_process, block or sleep
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>
2008-10-16 11:21:49 -07:00
David Fries
c30c9b1518 W1: fix deadlocks and remove w1_control_thread
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>
2008-10-16 11:21:49 -07:00
Adrian Bunk
6a873403d3 [PATCH] drivers/w1/w1.c: fix a compile error
From: Adrian Bunk <bunk@stusta.de>

drivers/w1/w1.c:197: error: static declaration of 'w1_bus_type' follows non-static declaration
drivers/w1/w1.h:217: error: previous declaration of 'w1_bus_type' was here

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-22 11:22:51 -07:00
Evgeniy Polyakov
70d484bff4 [PATCH] W1: possible cleanups
This patch contains the following possible cleanups:
- the following file did't #include the header with the prototypes for
  it's global functions:
  - w1_int.c
- #if 0 the following unused global function:
  - w1_family.c: w1_family_get()
- make the following needlessly global functions static:
  - w1_family.c: __w1_family_put()
  - w1_io.c: w1_delay()
  - w1_io.c: w1_touch_bit()
  - w1_io.c: w1_read_8()
- remove the following unused EXPORT_SYMBOL's:
  - w1_family.c: w1_family_put
  - w1_family.c: w1_family_registered

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-22 11:22:50 -07:00
Evgeniy Polyakov
2c5bfdac33 [PATCH] W1: cleanups
Nice cleanup spotted by Adrian Bunk, which was lost due to moving to the
completely new functionality.

Shame-shame-shame on me.

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-22 11:22:50 -07:00
Evgeniy Polyakov
abd52a1320 [PATCH] w1: Use mutexes instead of semaphores.
Use mutexes instead of semaphores.
Patch tested on x86_64 and i386 with test bus master driver.

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-22 11:22:50 -07:00
Evgeniy Polyakov
12003375ac [PATCH] w1: Userspace communication protocol over connector.
There are three types of messages between w1 core and userspace:
1. Events. They are generated each time new master or slave device found
	either due to automatic or requested search.
2. Userspace commands. Includes read/write and search/alarm search comamnds.
3. Replies to userspace commands.

From: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-22 11:22:50 -07:00
Evgeniy Polyakov
f522d23961 [PATCH] w1: Added default generic read/write operations.
Special file in each w1 slave device's directory called "rw" is created
each time new slave and no appropriate w1 family is registered.
"rw" file supports read and write operations, which allows to perform
almost any kind of operations. Each logical operation is a transaction
in nature, which can contain several (two or one) low-level operations.
Let's see how one can read EEPROM context:
1. one must write control buffer, i.e. buffer containing command byte
and two byte address. At this step bus is reset and appropriate device
is selected using either W1_SKIP_ROM or W1_MATCH_ROM command.
Then provided control buffer is being written to the wire.
2. reading. This will issue reading eeprom response.

It is possible that between 1. and 2. w1 master thread will reset bus for
searching and slave device will be even removed, but in this case 0xff will
be read, since no device was selected.

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-22 11:22:50 -07:00
Evgeniy Polyakov
674a396c6d [PATCH] w1: use kthread api.
This patch removes old-style kernel thread initialization
and changes w1 to use kthread api.
It is based on Christoph Hellwig <hch@lst.de> work.

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-23 17:28:13 -08:00
Adrian Bunk
a9fb1c7b95 [PATCH] w1: misc cleanups
This patch contains the following cleanups:
- make needlessly global code static
- declarations for global code belong into header files
- w1.c: #if 0 the unused struct w1_slave_device

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-23 17:28:12 -08:00
Evgeniy Polyakov
ccd6994000 [PATCH] W1: Change the type 'unsigned long' member of 'struct w1_bus_master' to 'void *'.
Signed-off-by: Ben Gardner <bgardner@wabtec.com>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-23 17:28:11 -08:00
Evgeniy Polyakov
a45f105ad4 [PATCH] w1: added private family data into w1_slave strucutre.
Add family_data to struct w1_slave.

Signed-off-by: Ben Gardner <bgardner@wabtec.com>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-08 14:41:27 -07:00
Evgeniy Polyakov
3aca692d3e [PATCH] w1: Detouching bug fixed.
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-08 14:41:26 -07:00
Evgeniy Polyakov
d2a4ef6a0c [PATCH] w1: Added add/remove slave callbacks.
Patch is based on work from Ben Gardner <bgardner@wabtec.com>

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-08 14:41:26 -07:00
Evgeniy Polyakov
db2d0008de [PATCH] w1: Added inline functions on top of container_of().
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-08 14:41:26 -07:00
Evgeniy Polyakov
6adf87bd7b [PATCH] w1: reconnect feature.
I've created reconnect feature - if on start there are no registered families
all new devices will have defailt family, later when driver for appropriate
family is loaded, slaves, which were faound earlier, will still have defult
family instead of right one. Reconnect feature will force control thread to run
through all master devices and all slaves found and search for slaves with
default family id and try to reconnect them.

It does not store newly registered family and does not check only those slaves
which have reg_num.family the same as being registered one - all slaves with
default family are reconnected.

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-21 21:43:12 -07:00
Evgeniy Polyakov
2a9d0c1781 [PATCH] w1: Adds a sysfs entry (w1_master_search) that allows you to disable/enable periodic searches.
Adds a sysfs entry (w1_master_search) that allows you to disable/enable
periodic searches.

Signed-off-by: Ben Gardner <bgardner@wabtec.com>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-21 21:43:11 -07:00
Evgeniy Polyakov
6b72986183 [PATCH] w1: Added the triplet w1 master method and changes w1_search() to use it.
Adds the triplet w1 master method and changes w1_search() to use it.

Signed-off-by: Ben Gardner <bgardner@wabtec.com>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-21 21:43:11 -07:00
Evgeniy Polyakov
ca775c629a [PATCH] w1: new family structure.
Removed some fields which are not required.
First step for writing operations.
Now only read and read name remain.
Patch depends on w1 cleanups patch.

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-21 21:43:09 -07:00
Evgeniy Polyakov
7785925dd8 [PATCH] w1: cleanups.
- white space changes.
 - list_for_each_entry/list_for_each_entry_safe and reverse changes.
 - small coding style changes.
 - removed redundant NULL checks.
 - use attribute group and macros instead of direct device attributes.
Patch is havily based on work from Adrian Bunk and Dmitry Torokhov,
thanks guys.

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-21 21:43:09 -07:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
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!
2005-04-16 15:20:36 -07:00