Commit Graph

95 Commits

Author SHA1 Message Date
Ben Werbowyj
368451ea74 drivers: w1: style corrections-pointers-blanklines-comparisons
Correct pointer notations to include whitespace between
variable type and "*" character. Inserted blank line
after variable declatations at two locations.
Rearranged comparison within an if statment to have the
constant on the right-hand side.

Signed-off-by: Ben Werbowyj <ben.werbowyj@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 13:56:04 +02:00
Ben Werbowyj
aaf16f7d98 drivers: w1: removed assignment from within if statement
Assignment of variable count removed from within an if statment.
This was done at two locations in the file.

Signed-off-by: Ben Werbowyj <ben.werbowyj@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 13:56:04 +02:00
Ben Werbowyj
d4c3f97a06 drivers: w1: style corrections for parenthesis and braces
Inserted whitespace between command and open parenthesis
at two locations. Removed new line between open brace and
command/declaration at two locations.

Signed-off-by: Ben Werbowyj <ben.werbowyj@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 13:56:04 +02:00
Andrew F. Davis
939fc83229 w1: add helper macro module_w1_family
The helper macro module_w1_family can be used in module drivers that
only register a w1 driver in their module init functions.  Add this
macro and use it in all applicable drivers.

Link: http://lkml.kernel.org/r/20160531204313.20979-2-afd@ti.com
Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: 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>
2016-08-02 19:35:39 -04:00
Andrew F. Davis
098f9fb0c9 w1: remove need for ida and use PLATFORM_DEVID_AUTO
PLATFORM_DEVID_AUTO can be used to have the platform core assign a
unique ID instead of manually creating one with IDA.  Do this in all
applicable drivers.

Link: http://lkml.kernel.org/r/20160531204313.20979-1-afd@ti.com
Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: 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>
2016-08-02 19:35:39 -04:00
Ben Sen
0a19f129d7 w1: add ability to set (SRAM) and store (EEPROM) configuration for temp sensors like DS18B20
Since many temperature sensors come "preconfigured" with a lower
precision, people are stuck at that precision when running on a kernel
based device (unlike the Dallas 1Wire library for e.g. Arduino, which
supports writing the configuration/scratchpad). This patch adds write
support for the scratchpad/precision registers via w1_slave sysfs.

Signed-off-by: Ben Sen <0.x29a.0@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-01 14:37:49 -07:00
Andrew F. Davis
424cfde49a power: bq27xxx_battery: Platform initialization must declare a device
When initialized as a platform device the initializer must now specify
a device. An empty device name is no longer valid.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
2015-09-23 16:23:12 +02:00
Andrew F. Davis
081bab217d power: bq27x00_battery: Renaming for consistency
Rename functions that are used by multiple devices. New devices
have been added and the function names and driver name are no longer
general enough for the functionality they provide.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: GUAN Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
2015-09-23 16:16:22 +02:00
Dan Carpenter
0c6d5c89a1 w1: use correct lock on error in w1_seq_show()
I noticed there was a problem here because Smatch complained:

	drivers/w1/slaves/w1_therm.c:416 w1_seq_show() warn:
	inconsistent returns 'mutex:&sl->master->mutex'.
	  Locked on:   line 416
	  Unlocked on: line 413

The problem is that we lock ->mutex but we unlock ->bus_mutex on error.
David Fries says that ->bus_mutex is correct and ->mutex is incorrect.

Fixes: d9411e57dc ('w1: Add support for DS28EA00 sequence to w1-therm')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-12 16:58:33 -07:00
Dan Carpenter
a14ef24b07 w1: fix for loop exit condition in w1_seq_show()
The W1_42_FINISHED_BYTE is 0xFF so the cast means the condition is
never true.

Fixes: d9411e57dc ('w1: Add support for DS28EA00 sequence to w1-therm')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-12 16:58:33 -07:00
Matt Campbell
d9411e57dc w1: Add support for DS28EA00 sequence to w1-therm
This patch provides support for the DS28EA00 digital thermometer.

The DS28EA00 provides an additional two pins for implementing a sequence
detection algorithm.  This feature allows you to determine the physical
location of the chip in the 1-wire bus without needing pre-existing
knowledge of the bus ordering.  Support is provided through the sysfs
w1_seq file.  The file will contain a single line with an integer value
representing the device index in the bus starting at 0.

Signed-off-by: Matt Campbell <mattrcampbell@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24 12:08:59 -07:00
David Fries
f7134eea05 w1_therm reference count family data
A temperature conversion can take 750 ms and when possible the
w1_therm slave driver drops the bus_mutex to allow other bus
operations, but that includes operations such as a periodic slave
search, which can remove this slave when it is no longer detected.
If that happens the sl->family_data will be freed and set to NULL
causing w1_slave_show to crash when it wakes up.

Signed-off-by: David Fries <David@Fries.net>
Reported-By: Thorsten Bschorr <thorsten@bschorr.de>
Tested-by: Thorsten Bschorr <thorsten@bschorr.de>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24 12:08:59 -07:00
NeilBrown
4b7e4f8289 w1: support auto-load of w1_bq27000 module.
1/ change request_module call to zero-pad single digit
   family numbers.  This appears to be the intention of
   the code, but not what it actually does.

   This means that the alias created for W1_FAMILY_SMEM_01
   might actually be useful.

2/ Define a family name for the BQ27000 battery charge monitor.
   Unfortunately this is the same number as W1_FAMILY_SMEM_01
   so if both a compiled on a system, one module might need to
   be blacklisted.

3/ Add a MODULE_ALIAS for the bq27000.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-26 19:09:02 -08:00
Arnd Bergmann
6b5fa77608 w1: select crc16 library for ds2406
commit 94859308a2 "w1: new w1_ds2406 driver" added a new driver
that uses the crc16 library, but didn't ensure that the core is
there. This adds the necessary Kconfig statements, just like we
have it for other w1 drivers.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Scott Alfter <scott@alfter.us>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-23 12:38:08 -04:00
Fjodor Schelichow
ea022eac1e w1/slaves: use pr_* instead of printk
This patch replaces all calls to the "printk" function within the "slaves"
subdirectory 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>
2014-06-19 17:46:51 -07:00
Scott Alfter
94859308a2 w1: new w1_ds2406 driver
Some preliminary work at making use of this driver led me to implement
CRC-16 checks on read and write to deal with the occasional glitchiness of
the 1-Wire bus.  The revised driver (attached) returns an I/O error if the
CRC check fails.  When reading the chip's state, either you get a valid
indication or you get an I/O error.  When changing its state, either the
change is successful or an I/O error is returned.

Signed-off-by: Scott Alfter <scott@alfter.us>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-19 17:45:14 -07:00
Alexander Shiyan
adffe4ab96 w1: Remove excess dependencies on W1 for masters and slaves
Configuration for masters and slaves is included only if W1 symbol
enabled, so no reason to check it once more.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-28 15:27:09 -08:00
David Fries
eb2c0da4ac w1: use family_data instead of rom in w1_slave
The first line printed from w1_slave gives the context of the w1
device.  So does the second line, but if the CRC check failed, the
second line contains the last successful result.  It is confusing when
it prints the temperature next to the line that might be a previous
conversion and has nothing to do with that printed temperature value.
Modify the code to store the last good conversion in family_data,
which is designed for custom data structures.

Signed-off-by: David Fries <David@Fries.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-07 15:40:18 -08:00
Greg Kroah-Hartman
eefafb79a4 w1: slaves: w1_ds2781: convert to use w1_family_ops.groups
This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-22 11:05:44 -07:00
Greg Kroah-Hartman
0597129cdc w1: slaves: w1_ds2760: convert to use w1_family_ops.groups
This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-22 11:05:44 -07:00
Greg Kroah-Hartman
9365261db4 w1: slaves: w1_ds2780: convert to use w1_family_ops.groups
This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-22 11:05:43 -07:00
Greg Kroah-Hartman
fa33a65a9c w1: slaves: w1_ds28e04: convert to use w1_family_ops.groups
This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-22 11:05:43 -07:00
Greg Kroah-Hartman
38f40982e1 w1: slaves: w1_ds2433: convert to use w1_family_ops.groups
This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-22 11:05:43 -07:00
Greg Kroah-Hartman
b3c6061dac w1: slaves: w1_ds2431: convert to use w1_family_ops.groups
This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-22 11:05:43 -07:00
Greg Kroah-Hartman
94c9e6d665 w1: slaves: w1_ds2423: convert to use w1_family_ops.groups
This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-22 11:05:43 -07:00
Greg Kroah-Hartman
729fb9d33f w1: slaves: w1_ds2413.c: convert to use w1_family_ops.groups
This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Cc: Mariusz Bialonczyk <manio@skyboo.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-22 11:05:43 -07:00
Greg Kroah-Hartman
32ea4175ae w1: slaves: w1_ds2408: convert to use w1_family_ops.groups
This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-22 11:05:42 -07:00
Greg Kroah-Hartman
b8a9f44fea w1: slaves: w1_therm: convert to use w1_family_ops.groups
This moves the sysfs file creation/removal to the w1 core by using the
.groups field, saving code in the slave driver.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: David Stevenson <david@avoncliff.com>
Cc: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Cc: Michael Arndt <michael@scriptkiller.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-22 11:05:42 -07:00
Jean-Francois Dagenais
d5528773e6 drivers/w1/slaves/w1_ds2408.c: add magic sequence to disable P0 test mode
Power-up timing

The DS2408 is sensitive to the power-on slew rate and can inadvertently
power up with a test mode feature enabled.  When this occurs, the P0 port
does not respond to the Channel Access Write command.  For most reliable
operation, it is recommended to disable the test mode after every power-on
reset using the Disable Test Mode sequence shown below.  The 64-bit ROM
code must be transmitted in the same bit sequence as with the Match ROM
command, i.e., least significant bit first.  This precaution is
recommended in parasite power mode (VCC pin connected to GND) as well as
with VCC power.

Disable Test Mode:
RST,PD,96h,<64-bit DS2408 ROM Code>,3Ch,RST,PD

[akpm@linux-foundation.org: don't use kerenldoc token to introduce a non-kerneldoc comment, tweak whitespace]
Signed-off-by: Jean-Francois Dagenais <jeff.dagenais@gmail.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>
2013-07-03 16:08:06 -07:00
Alexander Stein
8d7bda5188 w1: add family based automatic module loading
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>
2013-06-03 14:09:14 -07:00
Wei Yongjun
4d10e0f2dd drivers/w1/slaves/w1_ds2760.c: fix the error handling in w1_ds2760_add_slave()
Use platform_device_put() instead of platform_device_unregister() if
platform_device_add() fail, and platform_device_del() should be used in
the error handling case after platform_device_add() success.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Greg KH <greg@kroah.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:08 -07:00
Wei Yongjun
c28d6f2ddb drivers/w1/slaves/w1_ds2781.c: fix the error handling in w1_ds2781_add_slave()
Use platform_device_put() instead of platform_device_unregister() if
platform_device_add() fail, and platform_device_del() should be used in
the error handling case after platform_device_add() success.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Greg KH <greg@kroah.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:08 -07:00
Wei Yongjun
c5cfedf234 drivers/w1/slaves/w1_ds2780.c: fix the error handling in w1_ds2780_add_slave()
Use platform_device_put() instead of platform_device_unregister() if
platform_device_add() fail, and platform_device_del() should be used in
the error handling case after platform_device_add() success.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Greg KH <greg@kroah.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:08 -07:00
Wei Yongjun
0ece1bbf4c drivers/w1/slaves/w1_bq27000.c: fix the error handling in w1_bq27000_add_slave()
Use platform_device_put() instead of platform_device_unregister() if
platform_device_add() fails, and also add the return value check of
platform_device_add_data().

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Greg KH <greg@kroah.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:08 -07:00
Jean-Francois Dagenais
1116575d91 w1: ds2408: use ARRAY_SIZE instead of hard-coded number
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-15 12:15:02 -07:00
Jean-Francois Dagenais
aceca28544 w1: ds2408: make value read-back check a Kconfig option
De-activating this reading back will effectively half the time required
for a write to the output register.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-15 12:15:02 -07:00
Mariusz Bialonczyk
31b4ca3ef9 w1: add support for DS2413 Dual Channel Addressable Switch
Also fixes some whitespace inconsistency in Kconfig and w1_family.h when
DS2408 chip support was added.

Signed-off-by: Mariusz Bialonczyk <manio@skyboo.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:23 -08:00
Michael Arndt
29e5507ae4 w1: w1_therm: Add force-pullup option for "broken" sensors
Signed-off-by: Michael Arndt <michael@scriptkiller.de>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-18 13:55:24 -08:00
David Stevenson
867ff9880d w1_therm: Retries: remove old code add CRC
w1_therm includes some obsolete code to detect bad_roms, this is no
longer relevant.
The retry code is only used for this bad_rom test, however there is a
CRC check that detects a bad read, but does not trigger a retry. This
patch removes all the bad_rom code and uses the CRC check to trigger
retries.

Signed-off-by: David Stevenson <david@avoncliff.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15 23:43:05 -08:00
Raphael Assenat
f3261dfb55 1-Wire: Add support for the maxim ds1825 temperature sensor
This patch adds support for maxim ds1825 based 1-wire temperature sensors.

Signed-off-by: Raphael Assenat <raph@8d.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16 12:33:59 -07:00
Markus Franke
fbf7f7b4e2 w1: Add 1-wire slave device driver for DS28E04-100
Signed-off-by: Markus Franke <franm@hrz.tu-chemnitz.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13 16:47:10 -07:00
NeilBrown
b02f8bede2 W1: split master mutex to avoid deadlocks.
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>
2012-06-13 16:38:40 -07:00
Greg Kroah-Hartman
dd0aa67cd7 Revert "w1: introduce a slave mutex for serializing IO"
This reverts commit 59d4467be4.

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>
2012-06-13 16:33:54 -07:00
NeilBrown
59d4467be4 w1: introduce a slave mutex for serializing IO
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>
2012-06-12 15:27:32 -07:00
H Hartley Sweeten
4ae68e7345 w1: w1_ds2408.c: quite sparse noise about using plaing integer as NULL pointer
NULL not 0 should be used with pointers. Just remove the offending
lines since they will default to NULL anyway.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-04 16:25:30 -07:00
Greg Kroah-Hartman
c0a6720977 Revert "w1: Add 1-wire slave device driver for DS28E04-100"
This reverts commit f19420c1ac.

It contained lots of errors and warnings and shouldn't have ever been
applied, that was my fault, sorry.

Cc: Markus Franke <markus.franke@s2002.tu-chemnitz.de>
Cc: Evgeniy Polyakov <zbr@ioremap.net>,
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-29 22:12:08 -04:00
Dan Carpenter
eda70f1dfc w1: w1_ds28e04: unlock on error path in w1_f1C_write_pio()
We should unlock here before returning.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-18 15:37:35 -07:00
Markus Franke
f19420c1ac w1: Add 1-wire slave device driver for DS28E04-100
This patch adds a 1-wire slave device driver for the DS28E04-100.

Signed-off-by: Markus Franke <franm@hrz.tu-chemnitz.de>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-11 16:44:10 -07:00
Renata Sayakhova
fef37e9a47 DS2781 Maxim Stand-Alone Fuel Gauge battery and w1 slave drivers
Signed-off-by: Renata Sayakhova <rsayakhova@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-08 11:15:33 -08:00
NeilBrown
f6e8a1d7b4 w1_bq27000: Only one thread can access the bq27000 at a time.
If multiple threads try, they trip over each other badly.

Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-24 14:25:50 -08:00