reset: Fix crash when freeing non-existent optional resets

[ Upstream commit 4a6756f56bcf8e64c87144a626ce53aea4899c0e ]

When obtaining one or more optional resets, non-existent resets are
stored as

reset: Fix crash when freeing non-existent optional resets

[ Upstream commit 4a6756f56bcf8e64c87144a626ce53aea4899c0e ]

When obtaining one or more optional resets, non-existent resets are
stored as NULL pointers, and all related error and cleanup paths need to
take this into account.

Currently only reset_control_put() and reset_control_bulk_put()
get this right. All of __reset_control_bulk_get(),
of_reset_control_array_get(), and reset_control_array_put() lack the
proper checking, causing NULL pointer dereferences on failure or
release.

Fix this by moving the existing check from reset_control_bulk_put() to
__reset_control_put_internal(), so it applies to all callers.
The double check in reset_control_put() doesn't hurt.

Fixes: 17c82e206d2a3cd8 ("reset: Add APIs to manage array of resets")
Fixes: 48d71395896d54ee ("reset: Add reset_control_bulk API")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/2440edae7ca8534628cdbaf559ded288f2998178.1701276806.git.geert+renesas@glider.be
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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reset: ACPI reset support

Some of the IO devices like I2C or SPI require reset at runtime to
recover from an error condition without changing the power state of
the system. Added check for ACPI hand

reset: ACPI reset support

Some of the IO devices like I2C or SPI require reset at runtime to
recover from an error condition without changing the power state of
the system. Added check for ACPI handle and a call to method '__RST'
if supported. Devices using device tree method are unaffected by this.

Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
[p.zabel@pengutronix.de: wrap in #ifdef CONFIG_ACPI due to missing stubs]
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Link: https://lore.kernel.org/r/20220307135626.16673-1-kyarlagadda@nvidia.com

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reset: bail if try_module_get() fails

Abort instead of returning a new reset control for a reset controller
device that is going to have its module unloaded.

Reported-by: Uwe Kleine-König <u.kleine

reset: bail if try_module_get() fails

Abort instead of returning a new reset control for a reset controller
device that is going to have its module unloaded.

Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Fixes: 61fc41317666 ("reset: Add reset controller API")
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210607082615.15160-1-p.zabel@pengutronix.de
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: whitespace fixes

Fixes checkpatch issues:

CHECK: Alignment should match open parenthesis
#87: FILE: drivers/reset/core.c:87:
+static int of_reset_simple_xlate(struct reset_controller_d

reset: whitespace fixes

Fixes checkpatch issues:

CHECK: Alignment should match open parenthesis
#87: FILE: drivers/reset/core.c:87:
+static int of_reset_simple_xlate(struct reset_controller_dev *rcdev,
+ const struct of_phandle_args *reset_spec)

CHECK: Lines should not end with a '('
#540: FILE: drivers/reset/core.c:540:
+static struct reset_control *__reset_control_get_internal(

CHECK: Alignment should match open parenthesis
#603: FILE: drivers/reset/core.c:603:
+struct reset_control *__of_reset_control_get(struct device_node *node,
+ const char *id, int index, bool shared,

CHECK: Alignment should match open parenthesis
#781: FILE: drivers/reset/core.c:781:
+struct reset_control *__devm_reset_control_get(struct device *dev,
+ const char *id, int index, bool shared,

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: Add reset_control_bulk API

Follow the clock and regulator subsystems' lead and add a bulk API
for reset controls.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Tested-by: Dmitry Osip

reset: Add reset_control_bulk API

Follow the clock and regulator subsystems' lead and add a bulk API
for reset controls.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20210314154459.15375-5-digetx@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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reset: core: fix a kernel-doc markup

A function has a different name between their prototype
and its kernel-doc markup:

../drivers/reset/core.c:888: warning: expecting prototype for device_reset()

reset: core: fix a kernel-doc markup

A function has a different name between their prototype
and its kernel-doc markup:

../drivers/reset/core.c:888: warning: expecting prototype for device_reset(). Prototype was for __device_reset() instead

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: make shared pulsed reset controls re-triggerable

The current reset framework API does not allow to release what is done by
reset_control_reset(), IOW decrement triggered_count. Add the new
re

reset: make shared pulsed reset controls re-triggerable

The current reset framework API does not allow to release what is done by
reset_control_reset(), IOW decrement triggered_count. Add the new
reset_control_rearm() call to do so.

When reset_control_reset() has been called once, the counter
triggered_count, in the reset framework, is incremented i.e the resource
under the reset is in-use and the reset should not be done again.
reset_control_rearm() would be the way to state that the resource is
no longer used and, that from the caller's perspective, the reset can be
fired again if necessary.

Signed-off-by: Amjad Ouled-Ameur <aouledameur@baylibre.com>
Reported-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: bail if try_module_get() fails

[ Upstream commit 4fb26fb83f0def3d39c14e268bcd4003aae8fade ]

Abort instead of returning a new reset control for a reset controller
device that is going to have

reset: bail if try_module_get() fails

[ Upstream commit 4fb26fb83f0def3d39c14e268bcd4003aae8fade ]

Abort instead of returning a new reset control for a reset controller
device that is going to have its module unloaded.

Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Fixes: 61fc41317666 ("reset: Add reset controller API")
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210607082615.15160-1-p.zabel@pengutronix.de
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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reset: Fix and extend kerneldoc

Fix W=1 compile warnings (invalid kerneldoc):

drivers/reset/core.c:50: warning: Function parameter or member 'array' not described in 'reset_control'
drivers

reset: Fix and extend kerneldoc

Fix W=1 compile warnings (invalid kerneldoc):

drivers/reset/core.c:50: warning: Function parameter or member 'array' not described in 'reset_control'
drivers/reset/core.c:50: warning: Function parameter or member 'deassert_count' not described in 'reset_control'

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: Align logic and flow in managed helpers

__devm_reset_control_get() and devm_reset_control_array_get() are very
similar, but they do not look similar, due to inverted logic.
Make them more sim

reset: Align logic and flow in managed helpers

__devm_reset_control_get() and devm_reset_control_array_get() are very
similar, but they do not look similar, due to inverted logic.
Make them more similar, following the "bail out early" paradigm.

Adjust the logic and flow in devm_reset_controller_register() to match
the two other functions.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: Do not register resource data for missing resets

When an optional reset is not present, __devm_reset_control_get() and
devm_reset_control_array_get() still register resource data to release
t

reset: Do not register resource data for missing resets

When an optional reset is not present, __devm_reset_control_get() and
devm_reset_control_array_get() still register resource data to release
the non-existing reset on cleanup, which is futile.

Fix this by skipping NULL reset control pointers.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: Fix {of,devm}_reset_control_array_get kerneldoc return types

of_reset_control_array_get() and devm_reset_control_array_get() return
struct reset_control pointers, not internal struct reset_co

reset: Fix {of,devm}_reset_control_array_get kerneldoc return types

of_reset_control_array_get() and devm_reset_control_array_get() return
struct reset_control pointers, not internal struct reset_control_array
pointers, just like all other reset control API calls.

Correct the kerneldoc to match the code.

Fixes: 17c82e206d2a3cd8 ("reset: Add APIs to manage array of resets")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: improve of_xlate documentation

Mention of_reset_simple_xlate as the default if of_xlate is not set.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

reset: fix of_reset_control_get_count kerneldoc comment

Add a newline and remove a superfluous kerneldoc marker before the
of_reset_control_get_count kerneldoc comment, to fix documentation
build wa

reset: fix of_reset_control_get_count kerneldoc comment

Add a newline and remove a superfluous kerneldoc marker before the
of_reset_control_get_count kerneldoc comment, to fix documentation
build warnings:

./drivers/reset/core.c:832: warning: Incorrect use of kernel-doc format: * of_reset_control_get_count - Count number of resets available with a device
./drivers/reset/core.c:840: warning: Function parameter or member 'node' not described in 'of_reset_control_get_count'

Fixes: 17c82e206d2a ("reset: Add APIs to manage array of resets")
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: fix of_reset_simple_xlate kerneldoc comment

The flags parameter never made it into the API, but was erroneously
included in the kerneldoc comment. Remove it to fix a documentation
build warni

reset: fix of_reset_simple_xlate kerneldoc comment

The flags parameter never made it into the API, but was erroneously
included in the kerneldoc comment. Remove it to fix a documentation
build warning:

./drivers/reset/core.c:86: warning: Excess function parameter 'flags' description in 'of_reset_simple_xlate'

Fixes: 61fc41317666 ("reset: Add reset controller API")
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: Fix memory leak in reset_control_array_put()

Memory allocated for 'struct reset_control_array' in
of_reset_control_array_get() is never freed in
reset_control_array_put() resulting in kmemlea

reset: Fix memory leak in reset_control_array_put()

Memory allocated for 'struct reset_control_array' in
of_reset_control_array_get() is never freed in
reset_control_array_put() resulting in kmemleak showing
the following backtrace.

backtrace:
[<00000000c5f17595>] __kmalloc+0x1b0/0x2b0
[<00000000bd499e13>] of_reset_control_array_get+0xa4/0x180
[<000000004cc02754>] 0xffff800008c669e4
[<0000000050a83b24>] platform_drv_probe+0x50/0xa0
[<00000000d3a0b0bc>] really_probe+0x108/0x348
[<000000005aa458ac>] driver_probe_device+0x58/0x100
[<000000008853626c>] device_driver_attach+0x6c/0x90
[<0000000085308d19>] __driver_attach+0x84/0xc8
[<00000000080d35f2>] bus_for_each_dev+0x74/0xc8
[<00000000dd7f015b>] driver_attach+0x20/0x28
[<00000000923ba6e6>] bus_add_driver+0x148/0x1f0
[<0000000061473b66>] driver_register+0x60/0x110
[<00000000c5bec167>] __platform_driver_register+0x40/0x48
[<000000007c764b4f>] 0xffff800008c6c020
[<0000000047ec2e8c>] do_one_initcall+0x5c/0x1b0
[<0000000093d4b50d>] do_init_module+0x54/0x1d0

Fixes: 17c82e206d2a ("reset: Add APIs to manage array of resets")
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: Remove copy'n'paste redundancy in the comments

It seems the commit bb475230b8e5
("reset: make optional functions really optional")
brought couple of redundant lines in the comments.

Drop the

reset: Remove copy'n'paste redundancy in the comments

It seems the commit bb475230b8e5
("reset: make optional functions really optional")
brought couple of redundant lines in the comments.

Drop them here.

Cc: Ramiro Oliveira <Ramiro.Oliveira@synopsys.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: remove redundant null check on pointer dev

Pointer dev is being dereferenced when passed to the inlined
functon dev_name, however, dev is later being null checked
so at first this seems like

reset: remove redundant null check on pointer dev

Pointer dev is being dereferenced when passed to the inlined
functon dev_name, however, dev is later being null checked
so at first this seems like a potential null pointer dereference.

In fact, _reset_control_get_from_lookup is only ever called from
__reset_control_get, right after checking dev->of_node hence
dev can never be null. Clean this up by removing the redundant
null check.

Thanks to Philipp Zabel for spotting that dev can never be null.

Addresses-Coverity: ("Dereference before null check")
Fixes: 6691dffab0ab ("reset: add support for non-DT systems")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

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

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 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

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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reset: Add acquire/release support for arrays

Add implementations that apply acquire and release operations to all
reset controls part of a reset control array.

Signed-off-by: Thierry Reding <tredi

reset: Add acquire/release support for arrays

Add implementations that apply acquire and release operations to all
reset controls part of a reset control array.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: Add acquired flag to of_reset_control_array_get()

In order to be able to request an array of reset controls in acquired or
released mode, add the acquired flag to of_reset_control_array_get()

reset: Add acquired flag to of_reset_control_array_get()

In order to be able to request an array of reset controls in acquired or
released mode, add the acquired flag to of_reset_control_array_get() and
pass the flag to subsequent calls of __of_reset_control_get().

Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: add acquired/released state for exclusive reset controls

There are cases where a driver needs explicit control over a reset line
that is exclusively conneted to its device, but this control h

reset: add acquired/released state for exclusive reset controls

There are cases where a driver needs explicit control over a reset line
that is exclusively conneted to its device, but this control has to be
temporarily handed over to the power domain controller to handle reset
requirements during power transitions.
Allow multiple exclusive reset controls to be requested in 'released'
state for the same physical reset line, only one of which can be
acquired at the same time.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>

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reset: fix null pointer dereference on dev by dev_name

The call to dev_name will dereference dev, however, dev is later
being null checked, so there is a possibility of a null pointer
dereference on

reset: fix null pointer dereference on dev by dev_name

The call to dev_name will dereference dev, however, dev is later
being null checked, so there is a possibility of a null pointer
dereference on dev by the call to dev_name. Fix this by null
checking dev first before the call to dev_name

Detected by CoverityScan, CID#1475475 ("Dereference before null check")

Fixes: 2a6cb2b1d83b ("reset: Add reset_control_get_count()")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: Add reset_control_get_count()

Currently the reset core has internal support for counting the number of
resets for a device described in DT. Generalize this to devices using
lookup resets, an

reset: Add reset_control_get_count()

Currently the reset core has internal support for counting the number of
resets for a device described in DT. Generalize this to devices using
lookup resets, and export it for public use.

This will be used by generic drivers that need to be sure a device is
controlled by a single, dedicated reset line (e.g. vfio-platform).

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
[p.zabel@pengutronix.de: fixed a typo in reset_control_get_count comment]
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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reset: Fix potential use-after-free in __of_reset_control_get()

Calling of_node_put() decreases the reference count of a device tree
object, and may free some data.

However, the of_phandle_args str

reset: Fix potential use-after-free in __of_reset_control_get()

Calling of_node_put() decreases the reference count of a device tree
object, and may free some data.

However, the of_phandle_args structure embedding it is passed to
reset_controller_dev.of_xlate() after that, so it may still be accessed.

Move the call to of_node_put() down to fix this.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
[p.zabel@pengutronix.de: moved of_node_put after mutex_unlock]
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

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