reset: Add devres helpers to request pre-deasserted reset controls

Add devres helpers

- devm_reset_control_bulk_get_exclusive_deasserted
- devm_reset_control_bulk_get_optional_exclusive_deasserte

reset: Add devres helpers to request pre-deasserted reset controls

Add devres helpers

- devm_reset_control_bulk_get_exclusive_deasserted
- devm_reset_control_bulk_get_optional_exclusive_deasserted
- devm_reset_control_bulk_get_optional_shared_deasserted
- devm_reset_control_bulk_get_shared_deasserted
- devm_reset_control_get_exclusive_deasserted
- devm_reset_control_get_optional_exclusive_deasserted
- devm_reset_control_get_optional_shared_deasserted
- devm_reset_control_get_shared_deasserted

to request and immediately deassert reset controls. During cleanup,
reset_control_assert() will be called automatically on the returned
reset controls.

Acked-by: Uwe Kleine-König <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Philipp Zabel <[email protected]>

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reset: replace boolean parameters with flags parameter

Introduce enum reset_control_flags and replace the list of boolean
parameters to the internal reset_control_get functions with a single
flags p

reset: replace boolean parameters with flags parameter

Introduce enum reset_control_flags and replace the list of boolean
parameters to the internal reset_control_get functions with a single
flags parameter, before adding more boolean options.

The separate boolean parameters have been shown to be error prone in
the past. See for example commit a57f68ddc886 ("reset: Fix devm bulk
optional exclusive control getter").

Acked-by: Uwe Kleine-König <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Philipp Zabel <[email protected]>

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reset: core: add get_device()/put_device on rcdev

Since the rcdev structure is allocated by the reset controller drivers
themselves, they need to exists as long as there is a consumer. A call to
mod

reset: core: add get_device()/put_device on rcdev

Since the rcdev structure is allocated by the reset controller drivers
themselves, they need to exists as long as there is a consumer. A call to
module_get() is already existing but that does not work when using
device-tree overlays. In order to guarantee that the underlying reset
controller device does not vanish while using it, add a get_device() call
when retrieving a reset control from a reset controller device and a
put_device() when releasing that control.

Signed-off-by: Clément Léger <[email protected]>
Signed-off-by: Herve Codina <[email protected]>
Reviewed-by: Philipp Zabel <[email protected]>
Reviewed-by: Rob Herring (Arm) <[email protected]>
Reviewed-by: Andrew Lunn <[email protected]>
Reviewed-by: Steen Hegelund <[email protected]>
Acked-by: Krzysztof Kozlowski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Philipp Zabel <[email protected]>

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reset: simplify locking with guard()

Simplify error handling (less gotos) over locks with guard().

Signed-off-by: Krzysztof Kozlowski <[email protected]>
Reviewed-by: Philipp Zabel <p.

reset: simplify locking with guard()

Simplify error handling (less gotos) over locks with guard().

Signed-off-by: Krzysztof Kozlowski <[email protected]>
Reviewed-by: Philipp Zabel <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Philipp Zabel <[email protected]>

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reset: Instantiate reset GPIO controller for shared reset-gpios

Devices sharing a reset GPIO could use the reset framework for
coordinated handling of that shared GPIO line. We have several cases o

reset: Instantiate reset GPIO controller for shared reset-gpios

Devices sharing a reset GPIO could use the reset framework for
coordinated handling of that shared GPIO line. We have several cases of
such needs, at least for Devicetree-based platforms.

If Devicetree-based device requests a reset line, while "resets"
Devicetree property is missing but there is a "reset-gpios" one,
instantiate a new "reset-gpio" platform device which will handle such
reset line. This allows seamless handling of such shared reset-gpios
without need of changing Devicetree binding [1].

To avoid creating multiple "reset-gpio" platform devices, store the
Devicetree "reset-gpios" GPIO specifiers used for new devices on a
linked list. Later such Devicetree GPIO specifier (phandle to GPIO
controller, GPIO number and GPIO flags) is used to check if reset
controller for given GPIO was already registered.

If two devices have conflicting "reset-gpios" property, e.g. with
different ACTIVE_xxx flags, this would allow to spawn two separate
"reset-gpio" devices, where the second would fail probing on busy GPIO
request.

Link: https://lore.kernel.org/all/[email protected]/ [1]
Cc: Bartosz Golaszewski <[email protected]>
Cc: Chris Packham <[email protected]>
Cc: Sean Anderson <[email protected]>
Reviewed-by: Philipp Zabel <[email protected]>
Signed-off-by: Krzysztof Kozlowski <[email protected]>
Acked-by: Bartosz Golaszewski <[email protected]>
Acked-by: Linus Walleij <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Philipp Zabel <[email protected]>

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reset: Fix crash when freeing non-existent optional resets

When obtaining one or more optional resets, non-existent resets are
stored as NULL pointers, and all related error and cleanup paths need t

reset: Fix crash when freeing non-existent optional resets

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 <[email protected]>
Link: https://lore.kernel.org/r/2440edae7ca8534628cdbaf559ded288f2998178.1701276806.git.geert+renesas@glider.be
Signed-off-by: Philipp Zabel <[email protected]>

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reset: Annotate struct reset_control_array with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by

reset: Annotate struct reset_control_array with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct reset_control_array.
Additionally, since the element count member must be set before accessing
the annotated flexible array member, move its initialization earlier.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Philipp Zabel <[email protected]>
Reviewed-by: "Gustavo A. R. Silva" <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Kees Cook <[email protected]>

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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 <[email protected]>
[[email protected]: wrap in #ifdef CONFIG_ACPI due to missing stubs]
Signed-off-by: Philipp Zabel <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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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 <[email protected]>
Fixes: 61fc41317666 ("reset: Add reset controller API")
Acked-by: Uwe Kleine-König <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Philipp Zabel <[email protected]>

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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 <[email protected]>

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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 <[email protected]>
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 <[email protected]>
Tested-by: Dmitry Osipenko <[email protected]>
Signed-off-by: Dmitry Osipenko <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Mark Brown <[email protected]>

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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 <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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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 <[email protected]>
Reported-by: Jerome Brunet <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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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 <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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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 <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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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 <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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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 <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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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 <[email protected]>

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 <[email protected]>

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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 <[email protected]>

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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 <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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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 <[email protected]>
Signed-off-by: Andy Shevchenko <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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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 <[email protected]>
Reviewed-by: Bartosz Golaszewski <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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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 <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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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 <[email protected]>
Reviewed-by: Philipp Zabel <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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