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: Fix devm bulk optional exclusive control getter

Most likely due to copy-paste mistake the device managed version of the
denoted reset control getter has been implemented with invalid semantic

reset: Fix devm bulk optional exclusive control getter

Most likely due to copy-paste mistake the device managed version of the
denoted reset control getter has been implemented with invalid semantic,
which can be immediately spotted by having "WARN_ON(shared && acquired)"
warning in the system log as soon as the method is called. Anyway let's
fix it by altering the boolean arguments passed to the
__devm_reset_control_bulk_get() method from
- shared = true, optional = false, acquired = true
to
+ shared = false, optional = true, acquired = true
That's what they were supposed to be in the first place (see the non-devm
version of the same method: reset_control_bulk_get_optional_exclusive()).

Fixes: 48d71395896d ("reset: Add reset_control_bulk API")
Signed-off-by: Serge Semin <[email protected]>
Reviewed-by: Dmitry Osipenko <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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reset: Add of_reset_control_get_optional_exclusive()

Add optional variant of of_reset_control_get_exclusive(). If the
requested reset is not specified in the device tree, this function
returns NULL

reset: Add of_reset_control_get_optional_exclusive()

Add optional variant of of_reset_control_get_exclusive(). If the
requested reset is not specified in the device tree, this function
returns NULL instead of an error.

Suggested-by: Philipp Zabel <[email protected]>
Signed-off-by: Biju Das <[email protected]>
Reviewed-by: Geert Uytterhoeven <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Philipp Zabel <[email protected]>

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reset: add missing empty function reset_control_rearm()

All other functions are defined for when CONFIG_RESET_CONTROLLER
is not set.

Fixes: 557acb3d2cd9 ("reset: make shared pulsed reset controls r

reset: add missing empty function reset_control_rearm()

All other functions are defined for when CONFIG_RESET_CONTROLLER
is not set.

Fixes: 557acb3d2cd9 ("reset: make shared pulsed reset controls re-triggerable")
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jim Quinlan <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Cc: [email protected] # v5.11+

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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: Add devm_reset_control_get_optional_exclusive_released()

NVIDIA Tegra DRM and media drivers will need a resource-managed-optional
variant of reset_control_get_exclusive_released() in order to

reset: Add devm_reset_control_get_optional_exclusive_released()

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 <[email protected]> # Ouya T30
Tested-by: Nicolas Chauvet <[email protected]> # PAZ00 T20
Tested-by: Matt Merhar <[email protected]> # Ouya T30
Signed-off-by: Dmitry Osipenko <[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: document (devm_)reset_control_get_optional variants

Add kerneldoc comments for the optional reset_control_get variants.

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

reset: fix reset_control_get_exclusive kerneldoc comment

Add missing parentheses to correctly hyperlink the reference to
reset_control_get_shared().

Fixes: 0b52297f2288 ("reset: Add support for sha

reset: fix reset_control_get_exclusive kerneldoc comment

Add missing parentheses to correctly hyperlink the reference to
reset_control_get_shared().

Fixes: 0b52297f2288 ("reset: Add support for shared reset controls")
Reviewed-by: Hans de Goede <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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reset: fix linux/reset.h errors

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 ad

reset: fix linux/reset.h errors

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 <[email protected]>
Signed-off-by: Philipp Zabel <[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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reset: Add acquired flag to of_reset_control_array_get()

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

reset: Add acquired flag to of_reset_control_array_get()

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

Signed-off-by: Thierry Reding <[email protected]>
Acked-by: Felipe Balbi <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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reset: add acquired/released state for exclusive reset controls

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

reset: add acquired/released state for exclusive reset controls

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

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

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reset: Add reset_control_get_count()

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

reset: Add reset_control_get_count()

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

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

Signed-off-by: Geert Uytterhoeven <[email protected]>
[[email protected]: fixed a typo in reset_control_get_count comment]
Signed-off-by: Philipp Zabel <[email protected]>

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reset: Improve reset controller kernel docs

Grammar and indentation fixes.

Signed-off-by: Geert Uytterhoeven <[email protected]>
[[email protected]: dropped "shared among" -> "shared bet

reset: Improve reset controller kernel docs

Grammar and indentation fixes.

Signed-off-by: Geert Uytterhoeven <[email protected]>
[[email protected]: dropped "shared among" -> "shared between"]
Signed-off-by: Philipp Zabel <[email protected]>

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reset: Grammar s/more then once/more than once/

Fix grammar in reset_control_get_exclusive() documentation comment.

Signed-off-by: Geert Uytterhoeven <[email protected]>
Signed-off-by: Philip

reset: Grammar s/more then once/more than once/

Fix grammar in reset_control_get_exclusive() documentation comment.

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

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reset: remove reset_control_get(_optional)

No more users of these two.

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

reset: minimize the number of headers included from <linux/reset.h>

Commit 62e24c5775ec ("reset: add exported __reset_control_get, return
NULL if optional") moved the dev->of_node reference to core.

reset: minimize the number of headers included from <linux/reset.h>

Commit 62e24c5775ec ("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 <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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reset: remove remaining WARN_ON() in <linux/reset.h>

Commit bb475230b8e5 ("reset: make optional functions really optional")
gave a new meaning to _get_optional variants.

The differentiation by WARN

reset: remove remaining WARN_ON() in <linux/reset.h>

Commit bb475230b8e5 ("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 <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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reset: make device_reset_optional() really optional

Commit bb475230b8e5 ("reset: make optional functions really optional")
converted *_get_optional* functions, but device_reset_optional() was
left b

reset: make device_reset_optional() really optional

Commit bb475230b8e5 ("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 <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

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 <[email protected]>
Reviewed-by: Philippe Ombredanne <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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reset: Add APIs to manage array of resets

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

reset: Add APIs to manage array of resets

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 <[email protected]>
Cc: Jon Hunter <[email protected]>
Signed-off-by: Vivek Gautam <[email protected]>
[[email protected]: changed API to hide reset control arrays behind
struct reset_control]
Signed-off-by: Philipp Zabel <[email protected]>

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reset: add exported __reset_control_get, return NULL if optional

Rename the internal __reset_control_get/put functions to
__reset_control_get/put_internal and add an exported
__reset_control_get equ

reset: add exported __reset_control_get, return NULL if optional

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: bb475230b8e5 ("reset: make optional functions really optional")
Reported-by: Andy Shevchenko <[email protected]>
Tested-by: Andy Shevchenko <[email protected]>
Cc: Ramiro Oliveira <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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reset: fix optional reset_control_get stubs to return NULL

When RESET_CONTROLLER is not enabled, the optional reset_control_get
stubs should now also return NULL.

Since it is now valid for reset_co

reset: fix optional reset_control_get stubs to return NULL

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: bb475230b8e5 ("reset: make optional functions really optional")
Reported-by: Andrzej Hajda <[email protected]>
Tested-by: Andrzej Hajda <[email protected]>
Reviewed-by: Andrzej Hajda <[email protected]>
Cc: Ramiro Oliveira <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>

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