linux-toradex.git/drivers/w1/w1.c, branch v6.4-rc2 Linux kernel for Apalis and Colibri modules driver core: make struct bus_type.uevent() take a const * 2023-01-27T12:45:52+00:00 Greg Kroah-Hartman gregkh@linuxfoundation.org 2023-01-11T11:30:17+00:00 2a81ada32f0e584fc0c943e0d3a8c9f4fae411d6 The uevent() callback in struct bus_type should not be modifying the device that is passed into it, so mark it as a const * and propagate the function signature changes out into all relevant subsystems that use this callback. Acked-by: Rafael J. Wysocki <rafael@kernel.org> Acked-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20230111113018.459199-16-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The uevent() callback in struct bus_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-16-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
w1: fix WARNING after calling w1_process() 2023-01-19T16:26:33+00:00 Yang Yingliang yangyingliang@huawei.com 2022-12-05T10:15:58+00:00 36225a7c72e9e3e1ce4001b6ce72849f5c9a2d3b I got the following WARNING message while removing driver(ds2482): ------------[ cut here ]------------ do not call blocking ops when !TASK_RUNNING; state=1 set at [<000000002d50bfb6>] w1_process+0x9e/0x1d0 [wire] WARNING: CPU: 0 PID: 262 at kernel/sched/core.c:9817 __might_sleep+0x98/0xa0 CPU: 0 PID: 262 Comm: w1_bus_master1 Tainted: G N 6.1.0-rc3+ #307 RIP: 0010:__might_sleep+0x98/0xa0 Call Trace: exit_signals+0x6c/0x550 do_exit+0x2b4/0x17e0 kthread_exit+0x52/0x60 kthread+0x16d/0x1e0 ret_from_fork+0x1f/0x30 The state of task is set to TASK_INTERRUPTIBLE in loop in w1_process(), set it to TASK_RUNNING when it breaks out of the loop to avoid the warning. Fixes: 3c52e4e62789 ("W1: w1_process, block or sleep") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20221205101558.3599162-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
I got the following WARNING message while removing driver(ds2482):

------------[ cut here ]------------
do not call blocking ops when !TASK_RUNNING; state=1 set at [<000000002d50bfb6>] w1_process+0x9e/0x1d0 [wire]
WARNING: CPU: 0 PID: 262 at kernel/sched/core.c:9817 __might_sleep+0x98/0xa0
CPU: 0 PID: 262 Comm: w1_bus_master1 Tainted: G                 N 6.1.0-rc3+ #307
RIP: 0010:__might_sleep+0x98/0xa0
Call Trace:
 exit_signals+0x6c/0x550
 do_exit+0x2b4/0x17e0
 kthread_exit+0x52/0x60
 kthread+0x16d/0x1e0
 ret_from_fork+0x1f/0x30

The state of task is set to TASK_INTERRUPTIBLE in loop in w1_process(),
set it to TASK_RUNNING when it breaks out of the loop to avoid the
warning.

Fixes: 3c52e4e62789 ("W1: w1_process, block or sleep")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20221205101558.3599162-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
w1: fix deadloop in __w1_remove_master_device() 2023-01-19T16:26:31+00:00 Yang Yingliang yangyingliang@huawei.com 2022-12-05T08:04:34+00:00 25d5648802f12ae486076ceca5d7ddf1fef792b2 I got a deadloop report while doing device(ds2482) add/remove test: [ 162.241881] w1_master_driver w1_bus_master1: Waiting for w1_bus_master1 to become free: refcnt=1. [ 163.272251] w1_master_driver w1_bus_master1: Waiting for w1_bus_master1 to become free: refcnt=1. [ 164.296157] w1_master_driver w1_bus_master1: Waiting for w1_bus_master1 to become free: refcnt=1. ... __w1_remove_master_device() can't return, because the dev->refcnt is not zero. w1_add_master_device() | w1_alloc_dev() | atomic_set(&dev->refcnt, 2) | kthread_run() | |__w1_remove_master_device() | kthread_stop() // KTHREAD_SHOULD_STOP is set, | // threadfn(w1_process) won't be | // called. | kthread() | | // refcnt will never be 0, it's deadloop. | while (atomic_read(&dev->refcnt)) {...} After calling w1_add_master_device(), w1_process() is not really invoked, before w1_process() starting, if kthread_stop() is called in __w1_remove_master_device(), w1_process() will never be called, the refcnt can not be decreased, then it causes deadloop in remove function because of non-zero refcnt. We need to make sure w1_process() is really started, so move the set refcnt into w1_process() to fix this problem. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20221205080434.3149205-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
I got a deadloop report while doing device(ds2482) add/remove test:

  [  162.241881] w1_master_driver w1_bus_master1: Waiting for w1_bus_master1 to become free: refcnt=1.
  [  163.272251] w1_master_driver w1_bus_master1: Waiting for w1_bus_master1 to become free: refcnt=1.
  [  164.296157] w1_master_driver w1_bus_master1: Waiting for w1_bus_master1 to become free: refcnt=1.
  ...

__w1_remove_master_device() can't return, because the dev->refcnt is not zero.

w1_add_master_device()			|
  w1_alloc_dev()			|
    atomic_set(&dev->refcnt, 2)		|
  kthread_run()				|
					|__w1_remove_master_device()
					|  kthread_stop()
  // KTHREAD_SHOULD_STOP is set,	|
  // threadfn(w1_process) won't be	|
  // called.				|
  kthread()				|
					|  // refcnt will never be 0, it's deadloop.
					|  while (atomic_read(&dev->refcnt)) {...}

After calling w1_add_master_device(), w1_process() is not really
invoked, before w1_process() starting, if kthread_stop() is called
in __w1_remove_master_device(), w1_process() will never be called,
the refcnt can not be decreased, then it causes deadloop in remove
function because of non-zero refcnt.

We need to make sure w1_process() is really started, so move the
set refcnt into w1_process() to fix this problem.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20221205080434.3149205-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
w1/w1.c: w1 address crc quick for DS28E04 eeproms 2021-01-20T17:50:21+00:00 Christian Vogel vogelchr@vogel.cx 2021-01-13T19:50:17+00:00 48b7de6687f6ed597ef7162151f1c35469775545 Onewire addresses are 64bit family(8bit), unique_id(48bit), crc(8bit) (LSBt to MSB) and self-consistent: crc = crc8(family, unique). DS28E04-100 4096-Bit Addressable 1-Wire EEPROM with PIO have strap pins to set 7 LSB of the address, unfortunately without updating the crc part of the address. It is only consistent if all strap pins float high. [see datasheet 19-6134; Rev 12/11 page 6: 64-bit device id number] We therefore introduce a special handling of family 0x1c (DS28E04) to check address consistency with 7 LSBs of the unique_id set to 1. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Christian Vogel <vogelchr@vogel.cx> Link: https://lore.kernel.org/r/20210113195018.7498-2-vogelchr@vogel.cx Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Onewire addresses are 64bit family(8bit), unique_id(48bit), crc(8bit)
(LSBt to MSB) and self-consistent: crc = crc8(family, unique).

DS28E04-100 4096-Bit Addressable 1-Wire EEPROM with PIO have strap pins
to set 7 LSB of the address, unfortunately without updating the crc
part of the address. It is only consistent if all strap pins float high.
[see datasheet 19-6134; Rev 12/11 page 6: 64-bit device id number]

We therefore introduce a special handling of family 0x1c (DS28E04) to
check address consistency with 7 LSBs of the unique_id set to 1.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Christian Vogel <vogelchr@vogel.cx>
Link: https://lore.kernel.org/r/20210113195018.7498-2-vogelchr@vogel.cx
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
w1: Constify static w1_family_ops structs 2020-10-05T11:21:49+00:00 Rikard Falkeborn rikard.falkeborn@gmail.com 2020-10-04T19:32:01+00:00 57de2dfcabba91daedd66ac006b71734983975d6 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> 
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>
w1: Constify struct w1_family_ops 2020-10-05T11:21:49+00:00 Rikard Falkeborn rikard.falkeborn@gmail.com 2020-10-04T19:32:00+00:00 07f8569fbe44f35e53c7a5946fbb348432c68377 The fops field in the w1_family struct is never modified. Make it const to indicate that. Constifying the pointer makes it possible for drivers to declare static w1_family_ops structs const, which in turn will allow the compiler to put it in read-only memory. Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com> Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Link: https://lore.kernel.org/r/20201004193202.4044-2-rikard.falkeborn@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
The fops field in the w1_family struct is never modified. Make it const
to indicate that. Constifying the pointer makes it possible for drivers
to declare static w1_family_ops structs const, which in turn will allow
the compiler to put it in read-only memory.

Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Link: https://lore.kernel.org/r/20201004193202.4044-2-rikard.falkeborn@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30T18:26:37+00:00 Thomas Gleixner tglx@linutronix.de 2019-05-27T06:55:06+00:00 c942fddf8793b2013be8c901b47d0a8dc02bf99f Based on 3 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms 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 this program is free software you can redistribute it and or modify it under the terms 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 [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] 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 this program is free software you can redistribute it and or modify it under the terms 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 [author] [graeme] [gregory] [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema] [hk] [hemahk]@[ti] [com] 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1105 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Based on 3 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms 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

  this program is free software you can redistribute it and or modify
  it under the terms 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 [author] [kishon] [vijay] [abraham]
  [i] [kishon]@[ti] [com] 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

  this program is free software you can redistribute it and or modify
  it under the terms 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 [author] [graeme] [gregory]
  [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
  [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
  [hk] [hemahk]@[ti] [com] 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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
w1: core: match sub-nodes of bus masters in devicetree 2018-07-11T16:09:08+00:00 Daniel Mack daniel@zonque.org 2018-07-06T05:35:50+00:00 fae68031f7fbc8b6db58d87830ba7ed1d696fbb1 Once a new slave device is detected, match it against all sub-nodes of the master bus controller. If a match is found, set the slave device's of_node pointer. Signed-off-by: Daniel Mack <daniel@zonque.org> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk> 
Once a new slave device is detected, match it against all sub-nodes of the
master bus controller. If a match is found, set the slave device's of_node
pointer.

Signed-off-by: Daniel Mack <daniel@zonque.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
1wire: family module autoload fails because of upper/lower case mismatch. 2018-05-14T14:33:18+00:00 Ingo Flaschberger ingo.flaschberger@gmail.com 2018-05-01T14:10:33+00:00 065c09563c872e52813a17218c52cd642be1dca6 1wire family module autoload fails because of upper/lower  case mismatch. Signed-off-by: Ingo Flaschberger <ingo.flaschberger@gmail.com> Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
1wire family module autoload fails because of upper/lower
  case mismatch.

Signed-off-by: Ingo Flaschberger <ingo.flaschberger@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
w1: use put_device() if device_register() fail 2018-03-14T13:58:50+00:00 Arvind Yadav arvind.yadav.cs@gmail.com 2018-03-06T10:24:06+00:00 0ec4eb71b4956548a9c652f6c26232995916008c If device_register() returned an error! Always use put_device() to give up the reference initialized in device_register(). Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
If device_register() returned an error! Always use put_device()
to give up the reference initialized in device_register().

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>