Commit Graph

87 Commits

Author SHA1 Message Date
Claudiu Beznea
ccef9ef0aa reset: core: Drop unnecessary double quote
Drop unnecessary double quote.

Reported-by: Pavel Machek <pavel@nabladev.com>
Closes: https://lore.kernel.org/all/acJbYxKGAB4lxGQr@duo.ucw.cz
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-27 13:44:49 +01:00
Bartosz Golaszewski
62d11b80ea reset: don't overwrite fwnode_reset_n_cells
Fix a logic bug in reset_controller_register() where we set
fwnode_reset_n_cells to 1 if fwnode is set and fwnode_xlate is not but
we do it after assigning of_fwnode_handle(of_node) to fwnode.

Modify the logic to: assign fwnode from of_node if applicable, if fwnode
is still not set, try to get it from the device and only then check
of_xlate and fwnode_xlate and either assign fwnode_reset_n_cells from OF
or default to fwnode_reset_simple_xlate and fwnode_reset_n_cells = 1.

Fixes: ba8dbbb14b ("reset: convert the core API to using firmware nodes")
Reported-by: Mark Brown <broonie@kernel.org>
Closes: https://lore.kernel.org/all/0b72286b-33dd-4bc9-8c0e-161c2f4baed8@sirena.org.uk/
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Tested-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-11 08:27:21 +01:00
Philipp Zabel
2737dcb3c4 reset: core: Fix indentation
Correct an accidental whitespace change.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202603100730.J3pi4xqi-lkp@intel.com/
Fixes: 9035073d0e ("reset: convert reset core to using firmware nodes")
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-10 10:05:49 +01:00
Bartosz Golaszewski
9035073d0e reset: convert reset core to using firmware nodes
With everything else now in place, we can convert the remaining parts of
the reset subsystem to becoming fwnode-agnostic - meaning it will work
with all kinds of firmware nodes, not only devicetree.

To that end: extend struct reset_controller_dev with fields taking
information relevant for using firmware nodes (which mirrors what we
already do for OF-nodes) and limit using of_ APIs only to where it's
absolutely necessary (mostly around the of_xlate callback).

For backward compatibility of existing drivers we still support OF-nodes
but firmware nodes become the preferred method.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-09 10:20:04 +01:00
Bartosz Golaszewski
ba8dbbb14b reset: convert the core API to using firmware nodes
In order to simplify the commit converting the internals of reset core
to using firmware nodes, first convert the user-facing API. Modify the
signature of the core consumer functions but leave the specialized
wrappers as is to avoid modifying users for now.

No functional change intended.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-09 10:20:04 +01:00
Bartosz Golaszewski
9d52054a4f reset: convert of_reset_control_get_count() to using firmware nodes
Start the conversion of reset core to using firmware nodes by reworking
of_reset_control_get_count(). Unfortunately there is no fwnode-based
alternative to of_count_phandle_with_args() so we have to hand-code it.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-09 10:20:04 +01:00
Bartosz Golaszewski
8c91302a29 reset: protect struct reset_control with its own mutex
Currently we use a single, global mutex - misleadingly names
reset_list_mutex - to protect the global list of reset devices,
per-controller list of reset control handles and also internal fields of
struct reset_control. Locking can be made a lot more fine-grained if we
use a separate mutex for serializing operations on the list AND
accessing the reset control handle.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-09 10:20:04 +01:00
Bartosz Golaszewski
44a0acb2ca reset: protect struct reset_controller_dev with its own mutex
Currently we use a single, global mutex - misleadingly names
reset_list_mutex - to protect the global list of reset devices,
per-controller list of reset control handles and also internal fields of
struct reset_control. Locking can be made a lot more fine-grained if we
use a separate mutex for serializing operations on the list AND
accessing the reset controller device.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-09 10:20:04 +01:00
Bartosz Golaszewski
78ebbff6d1 reset: handle removing supplier before consumers
Except for the reset-gpio, all reset drivers use device tree - and as
such - benefit from the device links set up by driver core. This means,
that no reset supplier will be unbound before all its consumers have
been. For this reason, nobody bothered making the reset core resiliant
to the object life-time issues that are plagueing the kernel. In this
case: reset control handles referencing the reset provider device with
no serialization or NULL-pointer checking.

We now want to make the reset core fwnode-agnostic but before we do, we
must make sure it can survive unbinding of suppliers with consumers
still holding reset control handles.

To that end: use SRCU to protect the rcdev pointer inside struct
reset_control. We protect all sections using the pointer with SRCU
read-only critical sections and synchronize SRCU after every
modification of the pointer.

This is in line with what the GPIO subsystem does and what the proposed
revocable API tries to generalize. When and if the latter makes its way
into the kernel, reset core could potentially also be generalized to use
it.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-09 10:20:04 +01:00
Bartosz Golaszewski
1f10008aff reset: use lock guards in reset core
Simplify the locking code in reset core by using lock guard from
linux/cleanup.h.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-09 10:20:03 +01:00
Bartosz Golaszewski
6703784ab9 reset: fold ida_alloc() into reset_create_gpio_aux_device()
We don't need to know the IDA value outside of the function that creates
the auxiliary reset-gpio device. Simplify error handling by folding it
into reset_create_gpio_aux_device().

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-09 10:20:03 +01:00
Bartosz Golaszewski
20adbf3b8f reset: warn on reset-gpio release
While we implement an empty .release() callback for reset-gpio (driver
core requires it), this function will never actually be called as nobody
ever removes the device and the last reference is not dropped anywhere.

This is by design - once created, the reset-gpio device stays in memory.
Make the .release() callback emit a warning, should it ever be called
due to a programming bug.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-09 10:20:03 +01:00
Bartosz Golaszewski
ad9d28e68f reset: gpio: simplify fallback device matching
The of_args field of struct reset_controller_dev was introduced to allow
the reset-gpio driver to pass the phandle arguments back to reset core.
The thing is: it doesn't even have to do it. The core sets the platform
data of the auxiliary device *AND* has access to it later on during the
lookup. This means the field is unneeded and all can happen entirely in
reset core.

Remove the field from the public header and don't set it in
reset-gpio.c. Retrieve the platform data in reset core when needed
instead.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-09 10:17:50 +01:00
Bartosz Golaszewski
a9b95ce36d reset: gpio: add a devlink between reset-gpio and its consumer
The device that requests the reset control managed by the reset-gpio
device is effectively its consumer but the devlink is only established
between it and the GPIO controller exposing the reset pin. Add a devlink
between the consumer of the reset control and its supplier. This will
allow us to simplify the GPIOLIB code managing shared GPIOs when
handling the corner case of reset-gpio and gpiolib-shared interacting.
While at it and since we need to store the address of the auxiliary
device: don't allocate memory for the device separately but fold it into
struct reset_gpio_lookup instead.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-03-09 10:17:50 +01:00
Linus Torvalds
323bbfcf1e Convert 'alloc_flex' family to use the new default GFP_KERNEL argument
This is the exact same thing as the 'alloc_obj()' version, only much
smaller because there are a lot fewer users of the *alloc_flex()
interface.

As with alloc_obj() version, this was done entirely with mindless brute
force, using the same script, except using 'flex' in the pattern rather
than 'objs*'.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Linus Torvalds
bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook
69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Bartosz Golaszewski
b3d8508351 reset: gpio: add the "compatible" property
In order to correctly handle the interaction between the reset-gpio
devices and shared GPIOs managed by GPIOLIB, we need to be able to
identify the former. Add the "compatible" property to allow us to use
the device_is_compatible() helper.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2026-01-08 12:25:20 +01:00
Linus Torvalds
208eed95fc Merge tag 'soc-drivers-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull SoC driver updates from Arnd Bergmann:
 "This is the first half of the driver changes:

   - A treewide interface change to the "syscore" operations for power
     management, as a preparation for future Tegra specific changes

   - Reset controller updates with added drivers for LAN969x, eic770 and
     RZ/G3S SoCs

   - Protection of system controller registers on Renesas and Google
     SoCs, to prevent trivially triggering a system crash from e.g.
     debugfs access

   - soc_device identification updates on Nvidia, Exynos and Mediatek

   - debugfs support in the ST STM32 firewall driver

   - Minor updates for SoC drivers on AMD/Xilinx, Renesas, Allwinner, TI

   - Cleanups for memory controller support on Nvidia and Renesas"

* tag 'soc-drivers-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (114 commits)
  memory: tegra186-emc: Fix missing put_bpmp
  Documentation: reset: Remove reset_controller_add_lookup()
  reset: fix BIT macro reference
  reset: rzg2l-usbphy-ctrl: Fix a NULL vs IS_ERR() bug in probe
  reset: th1520: Support reset controllers in more subsystems
  reset: th1520: Prepare for supporting multiple controllers
  dt-bindings: reset: thead,th1520-reset: Add controllers for more subsys
  dt-bindings: reset: thead,th1520-reset: Remove non-VO-subsystem resets
  reset: remove legacy reset lookup code
  clk: davinci: psc: drop unused reset lookup
  reset: rzg2l-usbphy-ctrl: Add support for RZ/G3S SoC
  reset: rzg2l-usbphy-ctrl: Add support for USB PWRRDY
  dt-bindings: reset: renesas,rzg2l-usbphy-ctrl: Document RZ/G3S support
  reset: eswin: Add eic7700 reset driver
  dt-bindings: reset: eswin: Documentation for eic7700 SoC
  reset: sparx5: add LAN969x support
  dt-bindings: reset: microchip: Add LAN969x support
  soc: rockchip: grf: Add select correct PWM implementation on RK3368
  soc/tegra: pmc: Add USB wake events for Tegra234
  amba: tegra-ahb: Fix device leak on SMMU enable
  ...
2025-12-05 17:29:04 -08:00
Bartosz Golaszewski
5fc4e4cf7a reset: gpio: use software nodes to setup the GPIO lookup
GPIO machine lookup is a nice mechanism for associating GPIOs with
consumers if we don't know what kind of device the GPIO provider is or
when it will become available. However in the case of the reset-gpio, we
are already holding a reference to the device and so can reference its
firmware node. Let's setup a software node that references the relevant
GPIO and attach it to the auxiliary device we're creating.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2025-11-20 16:51:49 +01:00
Bartosz Golaszewski
109ce747ac reset: gpio: convert the driver to using the auxiliary bus
As the reset-gpio devices are purely virtual and never instantiated from
real firmware nodes, let's convert the driver to using the - more
fitting - auxiliary bus.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2025-11-20 16:51:48 +01:00
Bartosz Golaszewski
46dae84a90 reset: make the provider of reset-gpios the parent of the reset device
Auxiliary devices really do need a parent so ahead of converting the
reset-gpios driver to registering on the auxiliary bus, make the GPIO
device that provides the reset GPIO the parent of the reset-gpio device.
To that end move the lookup of the GPIO device by fwnode to the
beginning of __reset_add_reset_gpio_device() which has the added benefit
of bailing out earlier, before allocating resources for the virtual
device, if the chip is not up yet.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2025-11-20 16:51:48 +01:00
Bartosz Golaszewski
97d85328e3 reset: order includes alphabetically in reset/core.c
For better readability and easier maintenance order the includes
alphabetically.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2025-11-20 16:51:48 +01:00
Bartosz Golaszewski
8bffbfdc01 reset: remove legacy reset lookup code
There are no more users of this code. Let's remove the exported symbols
and the implementation from reset core.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
[p.zabel@pengutronix.de: folded in 8e6ec20e-8965-4b42-99fc-0462269ff2f1@paulmck-laptop]
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2025-11-18 17:52:54 +01:00
Philipp Zabel
d872bed850 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 <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/20240925-reset-get-deasserted-v2-2-b3601bbd0458@pengutronix.de
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2024-10-01 17:39:53 +02:00
Philipp Zabel
dad35f7d2f 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 a57f68ddc8 ("reset: Fix devm bulk
optional exclusive control getter").

Acked-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/20240925-reset-get-deasserted-v2-1-b3601bbd0458@pengutronix.de
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2024-10-01 17:39:53 +02:00
Clément Léger
a05f87270e 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 <clement.leger@bootlin.com>
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Steen Hegelund <Steen.Hegelund@microchip.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20240808154658.247873-8-herve.codina@bootlin.com
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2024-09-02 12:02:41 +02:00
Krzysztof Kozlowski
3ec21e7fa8 reset: simplify locking with guard()
Simplify error handling (less gotos) over locks with guard().

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Link: https://lore.kernel.org/r/20240825-reset-cleanup-scoped-v1-3-03f6d834f8c0@linaro.org
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2024-09-02 11:51:44 +02:00
Krzysztof Kozlowski
c721f189e8 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/YXi5CUCEi7YmNxXM@robh.at.kernel.org/ [1]
Cc: Bartosz Golaszewski <brgl@bgdev.pl>
Cc: Chris Packham <chris.packham@alliedtelesis.co.nz>
Cc: Sean Anderson <sean.anderson@seco.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20240129115216.96479-5-krzysztof.kozlowski@linaro.org
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2024-02-21 11:53:25 +01:00
Geert Uytterhoeven
4a6756f56b 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: 17c82e206d ("reset: Add APIs to manage array of resets")
Fixes: 48d7139589 ("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>
2023-11-30 15:02:21 +01:00
Kees Cook
fed2ef7aba 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 <p.zabel@pengutronix.de>
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230922175229.work.838-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
2023-10-24 14:10:04 -07:00
Krishna Yarlagadda
82816b4ffc 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
2022-05-03 17:41:25 +02:00
Philipp Zabel
4fb26fb83f 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: 61fc413176 ("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>
2021-06-07 11:26:31 +02:00
Philipp Zabel
1c5e05c23f 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>
2021-05-10 09:41:40 +02:00
Philipp Zabel
48d7139589 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>
2021-03-18 13:49:33 +00:00
Mauro Carvalho Chehab
ac9b7554af 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>
2021-01-14 09:22:13 +01:00
Amjad Ouled-Ameur
557acb3d2c 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>
2020-11-16 17:05:28 +01:00
Krzysztof Kozlowski
3315be5774 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>
2020-09-23 14:25:31 +02:00
Geert Uytterhoeven
a9457ed2eb 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>
2020-01-02 12:25:05 +01:00
Geert Uytterhoeven
db23808615 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>
2019-12-10 11:43:37 +01:00
Geert Uytterhoeven
723c0011c7 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: 17c82e206d ("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>
2019-12-10 11:43:37 +01:00
Linus Torvalds
ec939e4c94 Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC driver updates from Olof Johansson:
 "Various driver updates for platforms:

   - A larger set of work on Tegra 2/3 around memory controller and
     regulator features, some fuse cleanups, etc..

   - MMP platform drivers, in particular for USB PHY, and other smaller
     additions.

   - Samsung Exynos 5422 driver for DMC (dynamic memory configuration),
     and ASV (adaptive voltage), allowing the platform to run at more
     optimal operating points.

   - Misc refactorings and support for RZ/G2N and R8A774B1 from Renesas

   - Clock/reset control driver for TI/OMAP

   - Meson-A1 reset controller support

   - Qualcomm sdm845 and sda845 SoC IDs for socinfo"

* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (150 commits)
  firmware: arm_scmi: Fix doorbell ring logic for !CONFIG_64BIT
  soc: fsl: add RCPM driver
  dt-bindings: fsl: rcpm: Add 'little-endian' and update Chassis definition
  memory: tegra: Consolidate registers definition into common header
  memory: tegra: Ensure timing control debug features are disabled
  memory: tegra: Introduce Tegra30 EMC driver
  memory: tegra: Do not handle error from wait_for_completion_timeout()
  memory: tegra: Increase handshake timeout on Tegra20
  memory: tegra: Print a brief info message about EMC timings
  memory: tegra: Pre-configure debug register on Tegra20
  memory: tegra: Include io.h instead of iopoll.h
  memory: tegra: Adapt for Tegra20 clock driver changes
  memory: tegra: Don't set EMC rate to maximum on probe for Tegra20
  memory: tegra: Add gr2d and gr3d to DRM IOMMU group
  memory: tegra: Set DMA mask based on supported address bits
  soc: at91: Add Atmel SFR SN (Serial Number) support
  memory: atmel-ebi: switch to SPDX license identifiers
  memory: atmel-ebi: move NUM_CS definition inside EBI driver
  soc: mediatek: Refactor bus protection control
  soc: mediatek: Refactor sram control
  ...
2019-12-05 11:43:31 -08:00
Philipp Zabel
a48108c0c2 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>
2019-10-24 10:50:25 +02:00
Philipp Zabel
77d551b9ad 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: 17c82e206d ("reset: Add APIs to manage array of resets")
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2019-10-24 10:26:33 +02:00
Philipp Zabel
47db565251 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: 61fc413176 ("reset: Add reset controller API")
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2019-10-24 10:26:33 +02:00
Kishon Vijay Abraham I
532f9cd6ee 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: 17c82e206d ("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>
2019-10-22 10:56:41 +02:00
Andy Shevchenko
b89a8da92d reset: Remove copy'n'paste redundancy in the comments
It seems the commit bb475230b8
("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>
2019-10-03 19:56:51 +02:00
Olof Johansson
d9deea28a8 Merge tag 'reset-fixes-for-v5.2' of git://git.pengutronix.de/git/pza/linux into arm/drivers
Reset controller fix for v5.2

This tag removes a redundant device pointer NULL check from
__reset_control_get_from_lookup to fix a static code checker
warning.

* tag 'reset-fixes-for-v5.2' of git://git.pengutronix.de/git/pza/linux:
  reset: remove redundant null check on pointer dev

Link: https://lore.kernel.org/r/1562236626.6641.13.camel@pengutronix.de
Signed-off-by: Olof Johansson <olof@lixom.net>
2019-07-04 07:04:15 -07:00
Colin Ian King
a71dcd3757 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: 6691dffab0 ("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>
2019-07-04 12:10:55 +02:00
Thomas Gleixner
2874c5fd28 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>
2019-05-30 11:26:32 -07:00