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path: root/drivers/w1/slaves/w1_ds2423.c
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2020-10-05w1: Constify static w1_family_ops structsRikard Falkeborn1-1/+1
The only usage of these structs is to assign their address to the fops field in the w1_family struct, which is a const pointer. Make them const to allow the compiler to put them in read-only memory. This was done with the following Coccinelle semantic patch (http://coccinelle.lip6.fr/): // <smpl> @r1 disable optional_qualifier @ identifier i; position p; @@ static struct w1_family_ops i@p = {...}; @ok1@ identifier r1.i; position p; identifier s; @@ static struct w1_family s = { .fops=&i@p, }; @bad1@ position p!={r1.p,ok1.p}; identifier r1.i; @@ i@p @depends on !bad1 disable optional_qualifier@ identifier r1.i; @@ static +const struct w1_family_ops i={}; // </smpl> Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Link: https://lore.kernel.org/r/20201004193202.4044-3-rikard.falkeborn@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 147Thomas Gleixner1-14/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the [therms] of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 2 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190524100844.941364072@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09w1: Add subsystem kernel public interfaceAndrew F. Davis1-3/+3
Like other subsystems we should be able to define slave devices outside of the w1 directory. To do this we move public facing interface definitions to include/linux/w1.h and rename the internal definition file to w1_internal.h. As w1_family.h and w1_int.h contained almost entirely public driver interface definitions we simply removed these files and moved the remaining definitions into w1_internal.h. With this we can now start to move slave devices out of w1/slaves and into the subsystem based on the function they implement, again like other drivers. Signed-off-by: Andrew F. Davis <afd@ti.com> Reviewed-by: Sebastian Reichel <sre@kernel.org> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25w1: Organize driver source to natural/common orderAndrew F. Davis1-1/+1
Structures and functions should be ordered such that forward declaration use is minimized. MODULE_* macros should immediately follow the structures and functions upon which they act. Remaining MODULE_* macros should be at the end of the file in alphabetical order. Signed-off-by: Andrew F. Davis <afd@ti.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-02w1: add helper macro module_w1_familyAndrew F. Davis1-13/+1
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>
2013-08-22w1: slaves: w1_ds2423: convert to use w1_family_ops.groupsGreg Kroah-Hartman1-18/+9
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>
2013-06-03w1: add family based automatic module loadingAlexander Stein1-0/+1
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>
2012-06-13W1: split master mutex to avoid deadlocks.NeilBrown1-2/+2
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>
2011-01-13w1: DS2423 counter driver and documentationMika Laitio1-0/+166
This is a 1-wire/w1 DS2423 slave driver for reading the values from all 4 counters available DS2423 devices by using standard w1_slave file. In ds2423 the counters are tied to ram pages 12-15 in and each of those ram-pages. Each of these counter values (and asoociated ram page values) are represented as a own line in w1_slave file. Driver has been tested on mips and x86. usage example: cat /sys/bus/w1/devices/1d-00000009b964/w1_slave 00 02 00 00 00 00 00 00 00 6d 38 00 ff ff 00 00 fe ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=YES c=2 00 02 00 00 00 00 00 00 00 e0 1f 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=YES c=2 00 5a 0e 5f 18 00 00 00 00 0b 28 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff 00 00 ff ff crc=YES c=408882778 00 05 00 00 00 00 00 00 00 8d 39 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff crc=YES c=5 Patch includes also the documentation. [randy.dunlap@oracle.com: fix ds2423 build, needs to select CRC16] Signed-off-by: Mika Laitio <lamikr@pilppa.org> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.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>