Commit Graph

11 Commits

Author SHA1 Message Date
Greg Kroah-Hartman
b24413180f 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>
2017-11-02 11:10:55 +01:00
Chen-Yu Tsai
13e0dde8b2 clk: sunxi-ng: Support multiple variable pre-dividers
On the A83T, the AHB1 clock has a shared pre-divider on the two
PLL-PERIPH clock parents. To support such instances of shared
pre-dividers, this patch extends the mux clock type to support
multiple variable pre-dividers.

As the pre-dividers are only used to calculate the rate, but
do not participate in the factorization process, this is fairly
straightforward.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2017-06-07 15:32:15 +02:00
Maxime Ripard
d754b15951 clk: sunxi-ng: mux: Change pre-divider application function prototype
The current function name is a bit confusing, and doesn't really allow to
create an explicit function to reverse the operation.

We also for now change the parent rate through a pointer, while we don't
return anything.

In order to be less confusing, and easier to use for downstream users,
change the function name to something hopefully clearer, and return the
adjusted rate instead of changing the pointer.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
2017-06-07 15:32:13 +02:00
Maxime Ripard
10a8d9b906 clk: sunxi-ng: Pass the parent and a pointer to the clocks round rate
The clocks might need to modify their parent clocks. In order to make that
possible, give them access to the parent clock being evaluated, and to a
pointer to the parent rate so that they can modify it if needed.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
2017-06-07 15:32:13 +02:00
Maxime Ripard
13e91e4583 clk: sunxi-ng: mux: Add mux table macro
Add a new macro to declare muxes based on a table and a gate.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
2016-09-10 11:41:18 +02:00
Chen-Yu Tsai
8adfb08605 clk: sunxi-ng: mux: Add clk notifier functions
On sunxi we support cpufreq by changing the clock rate of PLL-CPU.
It's possible the clock output of the PLL goes out of the CPU's
operational limits when the PLL's multipliers / dividers are changed
and it hasn't stabilized yet. This would result in the CPU hanging.

To circumvent this, we temporarily switch the CPU mux clock to another
stable clock before the rate change, and switch it back after the PLL
stabilizes. This is done with clk notifiers registered on the PLL.

This patch adds common functions for notifiers to reparent mux clocks.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2016-08-25 22:30:36 +02:00
Chen-Yu Tsai
ff5294db41 clk: sunxi-ng: mux: support fixed pre-dividers on multiple parents
Some clocks on the A31 have fixed pre-dividers on multiple parents.
Add support for them.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2016-08-25 22:27:22 +02:00
Chen-Yu Tsai
2b9c875c56 clk: sunxi-ng: mux: Add support for mux tables
Some clock muxes have holes, i.e. invalid or unconnected inputs,
between parent mux values.

Add support for specifying a mux table to map clock parents to
mux values.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2016-08-25 22:26:44 +02:00
Maxime Ripard
89af85253c clk: sunxi-ng: mux: Rename mux macro to be consistent
Rename the internal mux macro to be consistent with the other internal
structure macros.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2016-08-25 22:25:53 +02:00
Chen-Yu Tsai
178ca5312a clk: sunxi-ng: mux: Increase fixed pre-divider div size
Some clocks have a predivider value that is larger than what u8 can
store. One such example is the OUT clk found on A20/A31, which has
a /750 pre-divider on one of the osc24M parents.

Increase the size of the div field to u16.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2016-08-08 20:03:20 +02:00
Maxime Ripard
2a65ed42dc clk: sunxi-ng: Add mux clock support
Some clocks in the Allwinner SoCs clocks unit are just muxes.

However, those muxes might also be found in some other complicated clocks
that would benefit from the code in there to deal with "advanced" features,
like pre-dividers.

Introduce a set of helpers to reduce the code duplication in such cases.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/20160629190535.11855-6-maxime.ripard@free-electrons.com
2016-07-08 18:04:42 -07:00