Commit Graph

55 Commits

Author SHA1 Message Date
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
Thierry Reding
22815f1825 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>
2019-03-20 11:18:53 +01:00
Thierry Reding
f31d5c24fb 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>
2019-03-20 11:18:36 +01:00
Philipp Zabel
c84b0326d5 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>
2019-03-20 11:16:55 +01:00
Colin Ian King
151f72f493 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>
2019-01-07 16:38:26 +01:00
Geert Uytterhoeven
eaf91db0ab 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>
2019-01-07 16:38:26 +01:00
Geert Uytterhoeven
b790c8ea55 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>
2018-10-08 15:25:21 +02:00
Kees Cook
acafe7e302 treewide: Use struct_size() for kmalloc()-family
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
    int stuff;
    void *entry[];
};

instance = kmalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL);

This patch makes the changes for kmalloc()-family (and kvmalloc()-family)
uses. It was done via automatic conversion with manual review for the
"CHECKME" non-standard cases noted below, using the following Coccinelle
script:

// pkey_cache = kmalloc(sizeof *pkey_cache + tprops->pkey_tbl_len *
//                      sizeof *pkey_cache->table, GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(sizeof(*VAR) + COUNT * sizeof(*VAR->ELEMENT), GFP)
+ alloc(struct_size(VAR, ELEMENT, COUNT), GFP)

// mr = kzalloc(sizeof(*mr) + m * sizeof(mr->map[0]), GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(sizeof(*VAR) + COUNT * sizeof(VAR->ELEMENT[0]), GFP)
+ alloc(struct_size(VAR, ELEMENT, COUNT), GFP)

// Same pattern, but can't trivially locate the trailing element name,
// or variable name.
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
expression SOMETHING, COUNT, ELEMENT;
@@

- alloc(sizeof(SOMETHING) + COUNT * sizeof(ELEMENT), GFP)
+ alloc(CHECKME_struct_size(&SOMETHING, ELEMENT, COUNT), GFP)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-06 11:15:43 -07:00