Merge abde0222 on remote branch

KernelVersion:	4.3

Contact:	linux-iio@vger.kernel.org

Description:

		Raw (unscaled no offset etc.) percentage reading of a substance.

		Raw (unscaled no offset etc.) reading of a substance. Units

		after application of scale and offset are percents.

What:		/sys/bus/iio/devices/iio:deviceX/in_resistance_raw

What:		/sys/bus/iio/devices/iio:deviceX/in_resistanceX_raw

			cut the overhead, others just disable the usage. So

			only cgroup_disable=memory is actually worthy}

	cgroup_no_v1=	[KNL] Disable one, multiple, all cgroup controllers in v1

			Format: { controller[,controller...] | "all" }

	cgroup_no_v1=	[KNL] Disable cgroup controllers and named hierarchies in v1

			Format: { { controller | "all" | "named" }

			          [,{ controller | "all" | "named" }...] }

			Like cgroup_disable, but only applies to cgroup v1;

			the blacklisted controllers remain available in cgroup2.

			"all" blacklists all controllers and "named" disables

			named mounts. Specifying both "all" and "named" disables

			all v1 hierarchies.

	cgroup.memory=	[KNL] Pass options to the cgroup memory controller.

			Format: <string>

::

    void (*qc_prep) (struct ata_queued_cmd *qc);

    enum ata_completion_errors (*qc_prep) (struct ata_queued_cmd *qc);

    int (*qc_issue) (struct ata_queued_cmd *qc);

  - R maps to r for user, group and others. On directories, R implies x.

  - If both W and D are allowed, w will be set.

  - W maps to w.

  - E maps to x.

  - H and P are always retained and ignored under Linux.

  - D is ignored.

  - A is always reset when a file is written to.

  - H, S and P are always retained and ignored under Linux.

  - A is cleared when a file is written to.

User id and group id will be used unless set[gu]id are given as mount

options. Since most of the Amiga file systems are single user systems

The Linux rwxrwxrwx file mode is handled as follows:

  - r permission will set R for user, group and others.

  - r permission will allow R for user, group and others.

  - w permission will allow W for user, group and others.

  - w permission will set W and D for user, group and others.

  - x permission of the user will allow E for plain files.

  - x permission of the user will set E for plain files.

  - D will be allowed for user, group and others.

  - All other flags (suid, sgid, ...) are ignored and will

    not be retained.

==============================

Building Linux with Clang/LLVM

==============================

This document covers how to build the Linux kernel with Clang and LLVM

utilities.

About

-----

The Linux kernel has always traditionally been compiled with GNU toolchains

such as GCC and binutils. Ongoing work has allowed for `Clang

<https://clang.llvm.org/>`_ and `LLVM <https://llvm.org/>`_ utilities to be

used as viable substitutes. Distributions such as `Android

<https://www.android.com/>`_, `ChromeOS

<https://www.chromium.org/chromium-os>`_, and `OpenMandriva

<https://www.openmandriva.org/>`_ use Clang built kernels.  `LLVM is a

collection of toolchain components implemented in terms of C++ objects

<https://www.aosabook.org/en/llvm.html>`_. Clang is a front-end to LLVM that

supports C and the GNU C extensions required by the kernel, and is pronounced

"klang," not "see-lang."

Clang

-----

The compiler used can be swapped out via `CC=` command line argument to `make`.

`CC=` should be set when selecting a config and during a build.

	make CC=clang defconfig

	make CC=clang

Cross Compiling

---------------

A single Clang compiler binary will typically contain all supported backends,

which can help simplify cross compiling.

	ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- make CC=clang

`CROSS_COMPILE` is not used to prefix the Clang compiler binary, instead

`CROSS_COMPILE` is used to set a command line flag: `--target <triple>`. For

example:

	clang --target aarch64-linux-gnu foo.c

LLVM Utilities

--------------

LLVM has substitutes for GNU binutils utilities. Kbuild supports `LLVM=1`

to enable them.

	make LLVM=1

They can be enabled individually. The full list of the parameters:

	make CC=clang LD=ld.lld AR=llvm-ar NM=llvm-nm STRIP=llvm-strip \\

	  OBJCOPY=llvm-objcopy OBJDUMP=llvm-objdump OBJSIZE=llvm-size \\

	  READELF=llvm-readelf HOSTCC=clang HOSTCXX=clang++ HOSTAR=llvm-ar \\

	  HOSTLD=ld.lld

Currently, the integrated assembler is disabled by default. You can pass

`LLVM_IAS=1` to enable it.

Getting Help

------------

- `Website <https://clangbuiltlinux.github.io/>`_

- `Mailing List <https://groups.google.com/forum/#!forum/clang-built-linux>`_: <clang-built-linux@googlegroups.com>

- `Issue Tracker <https://github.com/ClangBuiltLinux/linux/issues>`_

- IRC: #clangbuiltlinux on chat.freenode.net

- `Telegram <https://t.me/ClangBuiltLinux>`_: @ClangBuiltLinux

- `Wiki <https://github.com/ClangBuiltLinux/linux/wiki>`_

- `Beginner Bugs <https://github.com/ClangBuiltLinux/linux/issues?q=is%3Aopen+is%3Aissue+label%3A%22good+first+issue%22>`_

Getting LLVM

-------------

- http://releases.llvm.org/download.html

- https://github.com/llvm/llvm-project

- https://llvm.org/docs/GettingStarted.html

- https://llvm.org/docs/CMake.html

- https://apt.llvm.org/

- https://www.archlinux.org/packages/extra/x86_64/llvm/

- https://github.com/ClangBuiltLinux/tc-build

- https://github.com/ClangBuiltLinux/linux/wiki/Building-Clang-from-source

- https://android.googlesource.com/platform/prebuilts/clang/host/linux-x86/