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>
NVIDIA Tegra DRM and media drivers will need a resource-managed-optional
variant of reset_control_get_exclusive_released() in order to switch away
from a legacy Tegra-specific PD API to a GENPD API without much hassle.
Add the new reset helper to the reset API.
Tested-by: Peter Geis <pgwipeout@gmail.com> # Ouya T30
Tested-by: Nicolas Chauvet <kwizart@gmail.com> # PAZ00 T20
Tested-by: Matt Merhar <mattmerhar@protonmail.com> # Ouya T30
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
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>
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
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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
...
Add missing parentheses to correctly hyperlink the reference to
reset_control_get_shared().
Fixes: 0b52297f22 ("reset: Add support for shared reset controls")
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
The header file <linux/reset.h> uses errno constant(s) and the
ERR_PTR() macro but does not #include the appropriate header files
that provide those facilities, so add 2 header files to fix
build errors.
CC [M] drivers/gpu/drm/lima/lima_device.o
In file included from ../drivers/gpu/drm/lima/lima_device.c:5:0:
../include/linux/reset.h: In function ‘__device_reset’:
../include/linux/reset.h:77:25: error: ‘ENOTSUPP’ undeclared (first use in this function)
return optional ? 0 : -ENOTSUPP;
../include/linux/reset.h:77:25: note: each undeclared identifier is reported only once for each function it appears in
../include/linux/reset.h: In function ‘__of_reset_control_get’:
../include/linux/reset.h:85:36: error: ‘ENOTSUPP’ undeclared (first use in this function)
return optional ? NULL : ERR_PTR(-ENOTSUPP);
../include/linux/reset.h: In function ‘__reset_control_get’:
../include/linux/reset.h:93:36: error: ‘ENOTSUPP’ undeclared (first use in this function)
return optional ? NULL : ERR_PTR(-ENOTSUPP);
../include/linux/reset.h: In function ‘__devm_reset_control_get’:
../include/linux/reset.h:101:36: error: ‘ENOTSUPP’ undeclared (first use in this function)
return optional ? NULL : ERR_PTR(-ENOTSUPP);
../include/linux/reset.h: In function ‘devm_reset_control_array_get’:
../include/linux/reset.h:107:36: error: ‘ENOTSUPP’ undeclared (first use in this function)
return optional ? NULL : ERR_PTR(-ENOTSUPP);
../include/linux/reset.h: In function ‘of_reset_control_array_get’:
../include/linux/reset.h:114:36: error: ‘ENOTSUPP’ undeclared (first use in this function)
return optional ? NULL : ERR_PTR(-ENOTSUPP);
In file included from ../drivers/gpu/drm/lima/lima_device.c:5:0:
../include/linux/reset.h: In function ‘__devm_reset_control_get’:
../include/linux/reset.h:102:1: warning: control reaches end of non-void function [-Wreturn-type]
}
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
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>
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>
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>
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>
Commit 62e24c5775 ("reset: add exported __reset_control_get, return
NULL if optional") moved the dev->of_node reference to core.c, so
<linux/reset.h> does not need to know the members of struct device.
Declaring device and device_node as structure is enough.
<linux/types.h> is necessary for bool, true, and false.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Commit bb475230b8 ("reset: make optional functions really optional")
gave a new meaning to _get_optional variants.
The differentiation by WARN_ON() is not needed any more. We already
have inconsistency about this; (devm_)reset_control_get_exclusive()
has WARN_ON() check, but of_reset_control_get_exclusive() does not.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Commit bb475230b8 ("reset: make optional functions really optional")
converted *_get_optional* functions, but device_reset_optional() was
left behind. Convert it in the same way.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Many devices may want to request a bunch of resets and control them. So
it's better to manage them as an array. Add APIs to _get() an array of
reset_control, reusing the _assert(), _deassert(), and _reset() APIs for
single reset controls. Since reset controls already may control multiple
reset lines with a single hardware bit, from the user perspective, reset
control arrays are not at all different from single reset controls.
Note that these APIs don't guarantee that the reset lines managed in the
array are handled in any particular order.
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>
[p.zabel@pengutronix.de: changed API to hide reset control arrays behind
struct reset_control]
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Rename the internal __reset_control_get/put functions to
__reset_control_get/put_internal and add an exported
__reset_control_get equivalent to __of_reset_control_get
that takes a struct device parameter.
This avoids the confusing call to __of_reset_control_get in
the non-DT case and fixes the devm_reset_control_get_optional
function to return NULL if RESET_CONTROLLER is enabled but
dev->of_node == NULL.
Fixes: bb475230b8 ("reset: make optional functions really optional")
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Ramiro Oliveira <Ramiro.Oliveira@synopsys.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
When RESET_CONTROLLER is not enabled, the optional reset_control_get
stubs should now also return NULL.
Since it is now valid for reset_control_assert/deassert/reset/status/put
to be called unconditionally, with NULL as an argument for optional
resets, the stubs are not allowed to warn anymore.
Fixes: bb475230b8 ("reset: make optional functions really optional")
Reported-by: Andrzej Hajda <a.hajda@samsung.com>
Tested-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Cc: Ramiro Oliveira <Ramiro.Oliveira@synopsys.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
The *_get_optional_* functions weren't really optional so this patch
makes them really optional.
These *_get_optional_* functions will now return NULL instead of an error
if no matching reset phandle is found in the DT, and all the
reset_control_* functions now accept NULL rstc pointers.
Signed-off-by: Ramiro Oliveira <Ramiro.Oliveira@synopsys.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Since the new parameter being added is going to be a bool this patch
changes the shared flag from int to bool to match the new parameter.
Signed-off-by: Ramiro Oliveira <Ramiro.Oliveira@synopsys.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Standardise the way inline functions:
devm_reset_control_get_shared_by_index
devm_reset_control_get_exclusive_by_index
... are formatted.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Consumers need to be able to specify whether they are requesting an
'exclusive' or 'shared' reset line no matter which API (of_*, devm_*,
etc) they are using. This change allows users of the optional_* API
in particular to specify that their request is for a 'shared' line.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Consumers need to be able to specify whether they are requesting an
'exclusive' or 'shared' reset line no matter which API (of_*, devm_*,
etc) they are using. This change allows users of the of_* API in
particular to specify that their request is for a 'shared' line.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Phasing out generic reset line requests enables us to make some better
decisions on when and how to (de)assert said lines. If an 'exclusive'
line is requested, we know a device *requires* a reset and that it's
preferable to act upon a request right away. However, if a 'shared'
reset line is requested, we can reasonably assume sure that placing a
device into reset isn't a hard requirement, but probably a measure to
save power and is thus able to cope with not being asserted if another
device is still in use.
In order allow gentle adoption and not to forcing all consumers to
move to the API immediately, causing administration headache between
subsystems, this patch adds some temporary stand-in shim-calls. This
will ease the burden at merge time and allow subsystems to migrate over
to the new API in a more realistic time-frame.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
We're about to split the current API into two, where consumers will
be forced to be explicit when requesting reset lines. The choice
will be to either the call the *_exclusive or *_shared variant
depending on whether they can actually tolorate not being asserted
when that request is made.
The new API will look like this once reorded and complete:
reset_control_get_exclusive()
reset_control_get_shared()
reset_control_get_optional_exclusive()
reset_control_get_optional_shared()
of_reset_control_get_exclusive()
of_reset_control_get_shared()
of_reset_control_get_exclusive_by_index()
of_reset_control_get_shared_by_index()
devm_reset_control_get_exclusive()
devm_reset_control_get_shared()
devm_reset_control_get_optional_exclusive()
devm_reset_control_get_optional_shared()
devm_reset_control_get_exclusive_by_index()
devm_reset_control_get_shared_by_index()
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Prior to commit 6c96f05c8b ("reset: Make [of_]reset_control_get[_foo]
functions wrappers"), the "optional" functions returned -ENOTSUPP when
CONFIG_RESET_CONTROLLER was not set.
Revert back to the old behavior by changing the new
__devm_reset_control_get() and __of_reset_control_get() functions to
return ERR_PTR(-ENOTSUPP) when compiled without CONFIG_RESET_CONTROLLER.
Otherwise they will return -EINVAL causing users to think that an error
occurred when CONFIG_RESET_CONTROLLER is not set.
Fixes: 6c96f05c8b ("reset: Make [of_]reset_control_get[_foo] functions wrappers")
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
The Mediatek's thermal driver fails to compile when the RESET_CONTROLLER
option is not set. Logically, as the driver depends on this option to compile,
the Kconfig should select it but actually that is not correct because the
Kconfig provides also the COMPILE_TEST to increase the compile test coverage.
By providing the missing 'device_reset' stub for the driver in reset.h, that
let the kernel to compile on different platforms with the Mediatek thermal
driver enabled with the COMPILE_TEST option.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
In some SoCs some hw-blocks share a reset control. Add support for this
setup by adding new:
reset_control_get_shared()
devm_reset_control_get_shared()
devm_reset_control_get_shared_by_index()
methods to get a reset_control. Note that this patch omits adding of_
variants, if these are needed later they can be easily added.
This patch also changes the behavior of the existing exclusive
reset_control_get() variants, if these are now called more then once
for the same reset_control they will return -EBUSY. To catch existing
drivers triggering this error (there should not be any) a WARN_ON(1)
is added in this path.
When a reset_control is shared, the behavior of reset_control_assert /
deassert is changed, for shared reset_controls these will work like the
clock-enable/disable and regulator-on/off functions. They will keep a
deassert_count, and only (re-)assert the reset after reset_control_assert
has been called as many times as reset_control_deassert was called.
Calling reset_control_assert without first calling reset_control_deassert
is not allowed on a shared reset control. Calling reset_control_reset is
also not allowed on a shared reset control.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
With both the regular, _by_index and _optional variants we already have
quite a few variants of [of_]reset_control_get[_foo], the upcoming
addition of shared reset lines support makes this worse.
This commit changes all the variants into wrappers around common core
functions. For completeness sake this commit also adds a new
devm_get_reset_control_by_index wrapper.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
ENOSYS is reserved to report invalid syscalls to userspace.
Consistently return ENOTSUPP to indicate that the driver doesn't support
the functionality or the reset framework is not enabled at all.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Add of_reset_control_get_by_index() to allow the drivers to get reset
device without knowing its name.
Signed-off-by: Vince Hsu <vinceh@nvidia.com>
[jonathanh@nvidia.com: Updated stub function to return -ENOTSUPP instead
of -ENOSYS which should only be used for system calls.]
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
So the drivers can be compiled with CONFIG_RESET_CONTROLLER disabled.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
There are cases where a system will want to read a reset status bit before
doing any other toggling. Add a reset_control_status helper function to the
reset controller API.
Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
of_reset_control_get is not declared static in drivers/reset/core.c, which
is correct as we want to use it elsewhere too. But it does not have a
protype declared anywhere under include/linux. Add a prototype / stub for it
to linux/reset.h to fix this.
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
This patch adds device_reset_optional and (devm_)reset_control_get_optional
variants that drivers can use to indicate they can function without control
over the reset line. For those functions, stubs are added so the drivers can
be compiled with CONFIG_RESET_CONTROLLER disabled.
Also, device_reset is annotated with __must_check. Drivers ignoring the return
value should use device_reset_optional instead.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
In some cases, you might need to deassert from reset an hardware block that
doesn't associated to a struct device (CPUs, timers, etc.).
Add a small helper to retrieve the reset controller from the device tree
without the need to pass a struct device.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
This adds a simple API for devices to request being reset
by separate reset controller hardware and implements the
reset signal device tree binding.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Pavel Machek <pavel@ucw.cz>
Linus Torvalds
Jim Quinlan
Philipp Zabel
Dmitry Osipenko
Amjad Ouled-Ameur
Randy Dunlap
Thierry Reding
Geert Uytterhoeven
Masahiro Yamada
Greg Kroah-Hartman
Vivek Gautam
Ramiro Oliveira
Lee Jones
John Youn
Daniel Lezcano
Hans de Goede
Vince Hsu
Axel Lin
Dinh Nguyen
Maxime Ripard