kbuild: replace $(if A,A,B) with $(or A,B)

$(or ...) is available since GNU Make 3.81, and useful to shorten the
code in some places.

Covert as follows:

$(if A,A,B) --> $(or A,B)

This patch also converts:

$(if A, A, B) --> $(or A, B)

Strictly speaking, the latter is not an equivalent conversion because
GNU Make keeps spaces after commas; if A is not empty, $(if A, A, B)
expands to " A", while $(or A, B) expands to "A".

Anyway, preceding spaces are not significant in the code hunks I touched.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

tools: iio: convert iio_generic_buffer to use new IIO buffer API

This change makes use of the new IIO buffer API to read data from an IIO
buffer.
It doesn't read the /sys/bus/iio/devices/iio:deviceX/scan_elements dir
anymore, it reads /sys/bus/iio/devices/iio:deviceX/bufferY, where all the
scan_elements have been merged together with the old/classical buffer
attributes.

And it makes use of the new IIO_BUFFER_GET_FD_IOCTL ioctl to get an FD for
the IIO buffer for which to read data from.
It also does a quick sanity check to see that -EBUSY is returned if reading
the chardev after the ioctl() has succeeded.

This was tested with the following cases:
1. Tested buffer0 works with ioctl()
2. Tested that buffer0 can't be opened via /dev/iio:deviceX after ioctl()
This check should be omitted under normal operation; it's being done
here to check that the driver change is sane
3. Moved valid buffer0 to be buffer1, and tested that data comes from it

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20210215104043.91251-25-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

tools: iio: Correctly add make dependency for iio_utils

iio tools fail to build correctly with make parallelization:

$ make -s -j24
fixdep: error opening depfile: ./.iio_utils.o.d: No such file or directory
make[1]: *** [/home/labbott/linux_upstream/tools/build/Makefile.build:96: iio_utils.o] Error 2
make: *** [Makefile:43: iio_event_monitor-in.o] Error 2
make: *** Waiting for unfinished jobs....

This is because iio_utils.o is used across multiple targets.
Fix this by making iio_utils.o a proper dependency.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

tools iio: Override CFLAGS assignments

So user could specify outside CFLAGS values.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190103161350.11446-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools iio: Override CFLAGS assignments

So user could specify outside CFLAGS values.

Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

tools: fix cross-compile var clobbering

Currently a number of Makefiles break when used with toolchains that
pass extra flags in CC and other cross-compile related variables (such
as --sysroot).

Thus we get this error when we use a toolchain that puts --sysroot in
the CC var:

~/src/linux/tools$ make iio
[snip]
iio_event_monitor.c:18:10: fatal error: unistd.h: No such file or directory
#include <unistd.h>
^~~~~~~~~~

This occurs because we clobber several env vars related to
cross-compiling with lines like this:

CC = $(CROSS_COMPILE)gcc

Although this will point to a valid cross-compiler, we lose any extra
flags that might exist in the CC variable, which can break toolchains
that rely on them (for example, those that use --sysroot).

This easily shows up using a Yocto SDK:

$ . [snip]/sdk/environment-setup-cortexa8hf-neon-poky-linux-gnueabi

$ echo $CC
arm-poky-linux-gnueabi-gcc -march=armv7-a -mfpu=neon -mfloat-abi=hard
-mcpu=cortex-a8
--sysroot=[snip]/sdk/sysroots/cortexa8hf-neon-poky-linux-gnueabi

$ echo $CROSS_COMPILE
arm-poky-linux-gnueabi-

$ echo ${CROSS_COMPILE}gcc
krm-poky-linux-gnueabi-gcc

Although arm-poky-linux-gnueabi-gcc is a cross-compiler, we've lost the
--sysroot and other flags that enable us to find the right libraries to
link against, so we can't find unistd.h and other libraries and headers.
Normally with the --sysroot flag we would find unistd.h in the sdk
directory in the sysroot:

$ find [snip]/sdk/sysroots -path '*/usr/include/unistd.h'
[snip]/sdk/sysroots/cortexa8hf-neon-poky-linux-gnueabi/usr/include/unistd.h

The perf Makefile adds CC = $(CROSS_COMPILE)gcc if and only if CC is not
already set, and it compiles correctly with the above toolchain.

So, generalize the logic that perf uses in the common Makefile and
remove the manual CC = $(CROSS_COMPILE)gcc lines from each Makefile.

Note that this patch does not fix cross-compile for all the tools (some
have other bugs), but it does fix it for all except usb and acpi, which
still have other unrelated issues.

I tested both with and without the patch on native and cross-build and
there appear to be no regressions.

Link: http://lkml.kernel.org/r/20180107214028.23771-1-martin@martingkelly.com
Signed-off-by: Martin Kelly <martin@martingkelly.com>
Acked-by: Mark Brown <broonie@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Pali Rohar <pali.rohar@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Robert Moore <robert.moore@intel.com>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Valentina Manea <valentina.manea.m@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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 <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>

iio: tools: add install section

Allow user to call install target.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: tools: move to tools buildsystem

There is a nice buildsystem dedicated for userspace tools in Linux kernel tree.
Switch iio target to be built by it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

tools/iio: Use include/uapi with __EXPORTED_HEADERS__

Use the local uapi headers to keep in sync with "recently" added enum
values like IIO_UVINDEX.

Build tested using:
$ make -C <kernelsrcdir> tools/iio
$ make -C <kernelsrcdir>/tools iio
$ make -C <kernelsrcdir>/tools/iio

This follows a strategy similar to that used by tools/hv, tools/net and
tools/leds among others.

Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

tools: iio: Rename generic_buffer to iio_generic_buffer

This makes it clear that generic_buffer is an IIO tool
and also complies with filename conventions in tools/iio.

Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

tools: iio: Add ability to install/uninstall

Add options to the Makefile for install/uninstall similar to other tools.

Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: make tools more cross-compilation friendly

When cross-compiling the IIO tools we need to opportunity to
specify a cross compiler prefix and some extra CFLAGS. This
patch enables this in the same way as for other stuff in
tools.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

tools: iio: Define _GNU_SOURCE in Makefile

Definition of _GNU_SOURCE is needed to get rid of some warnings, such
as:
warning: implicit declaration of function `asprintf'.

generic_buffer.c and iio_event_monitor.c define _GNU_SOURCE,
but it is also needed in lsiio.c and iio_utils.c. For this reason,
this patch adds the definition in Makefile and removes it from where
it already exists.

Signed-off-by: Roberta Dobrescu <roberta.dobrescu@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: Move iio userspace applications out of staging

This patch moves iio userspace applications out of staging, to tools/iio/
and adds a Makefile in order to compile them easily. It also adds tools/iio/
to MAINTAINERS file.

Signed-off-by: Roberta Dobrescu <roberta.dobrescu@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>