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>

45 files changed, 45 insertions, 0 deletions

diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index c99f363826f0..f7f761b02bed 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 # common clock types
 obj-$(CONFIG_HAVE_CLK)		+= clk-devres.o clk-bulk.o
 obj-$(CONFIG_CLKDEV_LOOKUP)	+= clkdev.o
diff --git a/drivers/clk/at91/Makefile b/drivers/clk/at91/Makefile
index c68947b65a4c..082596f37c1d 100644
--- a/drivers/clk/at91/Makefile
+++ b/drivers/clk/at91/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 #
 # Makefile for at91 specific clk
 #
diff --git a/drivers/clk/bcm/Makefile b/drivers/clk/bcm/Makefile
index a0c14fa4aa1e..e3f0cb0d90f3 100644
--- a/drivers/clk/bcm/Makefile
+++ b/drivers/clk/bcm/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_CLK_BCM_63XX)	+= clk-bcm63xx.o
 obj-$(CONFIG_CLK_BCM_KONA)	+= clk-kona.o
 obj-$(CONFIG_CLK_BCM_KONA)	+= clk-kona-setup.o
diff --git a/drivers/clk/clk-gemini.c b/drivers/clk/clk-gemini.c
index f940e5af845b..5e66e6c0205e 100644
--- a/drivers/clk/clk-gemini.c
+++ b/drivers/clk/clk-gemini.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Cortina Gemini SoC Clock Controller driver
  * Copyright (c) 2017 Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/clk/clk-tango4.c b/drivers/clk/clk-tango4.c
index eef75e305a59..34b22b7930fb 100644
--- a/drivers/clk/clk-tango4.c
+++ b/drivers/clk/clk-tango4.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/kernel.h>
 #include <linux/clk-provider.h>
 #include <linux/of_address.h>
diff --git a/drivers/clk/h8300/clk-div.c b/drivers/clk/h8300/clk-div.c
index 715b882205a8..4ae624425e9d 100644
--- a/drivers/clk/h8300/clk-div.c
+++ b/drivers/clk/h8300/clk-div.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * H8/300 divide clock driver
  *
diff --git a/drivers/clk/h8300/clk-h8s2678.c b/drivers/clk/h8300/clk-h8s2678.c
index a26312460621..fc24b0b55a3d 100644
--- a/drivers/clk/h8300/clk-h8s2678.c
+++ b/drivers/clk/h8300/clk-h8s2678.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * H8S2678 clock driver
  *
diff --git a/drivers/clk/hisilicon/Makefile b/drivers/clk/hisilicon/Makefile
index 1e4c3ddbad84..0e55612112af 100644
--- a/drivers/clk/hisilicon/Makefile
+++ b/drivers/clk/hisilicon/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 #
 # Hisilicon Clock specific Makefile
 #
diff --git a/drivers/clk/imx/Makefile b/drivers/clk/imx/Makefile
index 1ada68abb158..f91f2b2e11cd 100644
--- a/drivers/clk/imx/Makefile
+++ b/drivers/clk/imx/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 
 obj-y += \
 	clk.o \
diff --git a/drivers/clk/imx/clk-imx27.c b/drivers/clk/imx/clk-imx27.c
index cf5cf75a4848..0a0ab95d16fe 100644
--- a/drivers/clk/imx/clk-imx27.c
+++ b/drivers/clk/imx/clk-imx27.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/clk.h>
 #include <linux/clk-provider.h>
 #include <linux/clkdev.h>
diff --git a/drivers/clk/imx/clk-pllv1.c b/drivers/clk/imx/clk-pllv1.c
index 82fe3662b5f6..e47a1c2fe8bd 100644
--- a/drivers/clk/imx/clk-pllv1.c
+++ b/drivers/clk/imx/clk-pllv1.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/clk-provider.h>
 #include <linux/io.h>
 #include <linux/slab.h>
diff --git a/drivers/clk/imx/clk-pllv2.c b/drivers/clk/imx/clk-pllv2.c
index 4aeda56ce372..9842d657e974 100644
--- a/drivers/clk/imx/clk-pllv2.c
+++ b/drivers/clk/imx/clk-pllv2.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/kernel.h>
 #include <linux/clk.h>
 #include <linux/io.h>
diff --git a/drivers/clk/imx/clk.c b/drivers/clk/imx/clk.c
index a634b1185be3..9074e6974b6d 100644
--- a/drivers/clk/imx/clk.c
+++ b/drivers/clk/imx/clk.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/of.h>
diff --git a/drivers/clk/imx/clk.h b/drivers/clk/imx/clk.h
index d54f0720afba..d69c4bbf3597 100644
--- a/drivers/clk/imx/clk.h
+++ b/drivers/clk/imx/clk.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef __MACH_IMX_CLK_H
 #define __MACH_IMX_CLK_H
 
diff --git a/drivers/clk/mediatek/Makefile b/drivers/clk/mediatek/Makefile
index 2a755b5fb51b..ba2a070765f0 100644
--- a/drivers/clk/mediatek/Makefile
+++ b/drivers/clk/mediatek/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_COMMON_CLK_MEDIATEK) += clk-mtk.o clk-pll.o clk-gate.o clk-apmixed.o clk-cpumux.o
 obj-$(CONFIG_RESET_CONTROLLER) += reset.o
 obj-$(CONFIG_COMMON_CLK_MT6797) += clk-mt6797.o
diff --git a/drivers/clk/mmp/Makefile b/drivers/clk/mmp/Makefile
index 9d4bc41e4239..7bc7ac69391e 100644
--- a/drivers/clk/mmp/Makefile
+++ b/drivers/clk/mmp/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 #
 # Makefile for mmp specific clk
 #
diff --git a/drivers/clk/mmp/clk.c b/drivers/clk/mmp/clk.c
index 089927e4cda2..ad8d483a35cd 100644
--- a/drivers/clk/mmp/clk.c
+++ b/drivers/clk/mmp/clk.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/io.h>
 #include <linux/clk-provider.h>
 #include <linux/slab.h>
diff --git a/drivers/clk/mmp/clk.h b/drivers/clk/mmp/clk.h
index adf9b711b037..70bb73257647 100644
--- a/drivers/clk/mmp/clk.h
+++ b/drivers/clk/mmp/clk.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef __MACH_MMP_CLK_H
 #define __MACH_MMP_CLK_H
 
diff --git a/drivers/clk/mmp/reset.c b/drivers/clk/mmp/reset.c
index b4e4d6aa2631..ded7e391c737 100644
--- a/drivers/clk/mmp/reset.c
+++ b/drivers/clk/mmp/reset.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/slab.h>
 #include <linux/io.h>
 #include <linux/of.h>
diff --git a/drivers/clk/mmp/reset.h b/drivers/clk/mmp/reset.h
index be8b1a7000f7..3d0470ca3fd9 100644
--- a/drivers/clk/mmp/reset.h
+++ b/drivers/clk/mmp/reset.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef __MACH_MMP_CLK_RESET_H
 #define __MACH_MMP_CLK_RESET_H
 
diff --git a/drivers/clk/mvebu/Makefile b/drivers/clk/mvebu/Makefile
index d71c7fd5da16..93ac3685271f 100644
--- a/drivers/clk/mvebu/Makefile
+++ b/drivers/clk/mvebu/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_MVEBU_CLK_COMMON)	+= common.o
 obj-$(CONFIG_MVEBU_CLK_CPU) 	+= clk-cpu.o
 obj-$(CONFIG_MVEBU_CLK_COREDIV)	+= clk-corediv.o
diff --git a/drivers/clk/mvebu/dove-divider.c b/drivers/clk/mvebu/dove-divider.c
index 4091f3cfee19..7e35c891e168 100644
--- a/drivers/clk/mvebu/dove-divider.c
+++ b/drivers/clk/mvebu/dove-divider.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Marvell Dove PMU Core PLL divider driver
  *
diff --git a/drivers/clk/mvebu/dove-divider.h b/drivers/clk/mvebu/dove-divider.h
index 4f2f718deb8e..38ea373088ca 100644
--- a/drivers/clk/mvebu/dove-divider.h
+++ b/drivers/clk/mvebu/dove-divider.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef DOVE_DIVIDER_H
 #define DOVE_DIVIDER_H
 
diff --git a/drivers/clk/qcom/Makefile b/drivers/clk/qcom/Makefile
index 3f3aff229fb7..26410d31446b 100644
--- a/drivers/clk/qcom/Makefile
+++ b/drivers/clk/qcom/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_COMMON_CLK_QCOM) += clk-qcom.o
 
 clk-qcom-y += common.o
diff --git a/drivers/clk/renesas/Makefile b/drivers/clk/renesas/Makefile
index 9bda3ec5b199..cbbb081e2145 100644
--- a/drivers/clk/renesas/Makefile
+++ b/drivers/clk/renesas/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 # SoC
 obj-$(CONFIG_CLK_EMEV2)			+= clk-emev2.o
 obj-$(CONFIG_CLK_RZA1)			+= clk-rz.o
diff --git a/drivers/clk/renesas/clk-div6.h b/drivers/clk/renesas/clk-div6.h
index 567b31d2bfa5..065dfb49adf6 100644
--- a/drivers/clk/renesas/clk-div6.h
+++ b/drivers/clk/renesas/clk-div6.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef __RENESAS_CLK_DIV6_H__
 #define __RENESAS_CLK_DIV6_H__
 
diff --git a/drivers/clk/rockchip/Makefile b/drivers/clk/rockchip/Makefile
index 6f19826cc447..59b8d320960a 100644
--- a/drivers/clk/rockchip/Makefile
+++ b/drivers/clk/rockchip/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 #
 # Rockchip Clock specific Makefile
 #
diff --git a/drivers/clk/samsung/Makefile b/drivers/clk/samsung/Makefile
index 7afc21dc374e..23835001e8bd 100644
--- a/drivers/clk/samsung/Makefile
+++ b/drivers/clk/samsung/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 #
 # Samsung Clock specific Makefile
 #
diff --git a/drivers/clk/sirf/atlas6.h b/drivers/clk/sirf/atlas6.h
index 376217f3bf8f..cb871e30a175 100644
--- a/drivers/clk/sirf/atlas6.h
+++ b/drivers/clk/sirf/atlas6.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #define SIRFSOC_CLKC_CLK_EN0    0x0000
 #define SIRFSOC_CLKC_CLK_EN1    0x0004
 #define SIRFSOC_CLKC_REF_CFG    0x0020
diff --git a/drivers/clk/sirf/prima2.h b/drivers/clk/sirf/prima2.h
index 01bc3854a058..2fb56941795d 100644
--- a/drivers/clk/sirf/prima2.h
+++ b/drivers/clk/sirf/prima2.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #define SIRFSOC_CLKC_CLK_EN0    0x0000
 #define SIRFSOC_CLKC_CLK_EN1    0x0004
 #define SIRFSOC_CLKC_REF_CFG    0x0014
diff --git a/drivers/clk/socfpga/Makefile b/drivers/clk/socfpga/Makefile
index d8bb239753a4..9146c20fe21f 100644
--- a/drivers/clk/socfpga/Makefile
+++ b/drivers/clk/socfpga/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 obj-y += clk.o
 obj-y += clk-gate.o
 obj-y += clk-pll.o
diff --git a/drivers/clk/spear/Makefile b/drivers/clk/spear/Makefile
index cdb425d3b8ee..d7e75d2d42df 100644
--- a/drivers/clk/spear/Makefile
+++ b/drivers/clk/spear/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 #
 # SPEAr Clock specific Makefile
 #
diff --git a/drivers/clk/st/clkgen.h b/drivers/clk/st/clkgen.h
index f7ec2d9139d6..44302fc7ca96 100644
--- a/drivers/clk/st/clkgen.h
+++ b/drivers/clk/st/clkgen.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /************************************************************************
 File  : Clock H/w specific Information
 
diff --git a/drivers/clk/sunxi-ng/Makefile b/drivers/clk/sunxi-ng/Makefile
index 85a0633c1eac..d1c2fa93ddd9 100644
--- a/drivers/clk/sunxi-ng/Makefile
+++ b/drivers/clk/sunxi-ng/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 # Common objects
 lib-$(CONFIG_SUNXI_CCU)		+= ccu_common.o
 lib-$(CONFIG_SUNXI_CCU)		+= ccu_mmc_timing.o
diff --git a/drivers/clk/sunxi-ng/ccu_mult.h b/drivers/clk/sunxi-ng/ccu_mult.h
index f9c37b987d72..6b30b0c10807 100644
--- a/drivers/clk/sunxi-ng/ccu_mult.h
+++ b/drivers/clk/sunxi-ng/ccu_mult.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _CCU_MULT_H_
 #define _CCU_MULT_H_
 
diff --git a/drivers/clk/sunxi-ng/ccu_mux.h b/drivers/clk/sunxi-ng/ccu_mux.h
index f20c0bd62a47..f165395effb5 100644
--- a/drivers/clk/sunxi-ng/ccu_mux.h
+++ b/drivers/clk/sunxi-ng/ccu_mux.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _CCU_MUX_H_
 #define _CCU_MUX_H_
 
diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile
index 39d2044a1f49..be88368b48a1 100644
--- a/drivers/clk/sunxi/Makefile
+++ b/drivers/clk/sunxi/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 #
 # Makefile for sunxi specific clk
 #
diff --git a/drivers/clk/sunxi/clk-factors.h b/drivers/clk/sunxi/clk-factors.h
index 1e63c5b2d5f4..824f746b2567 100644
--- a/drivers/clk/sunxi/clk-factors.h
+++ b/drivers/clk/sunxi/clk-factors.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef __MACH_SUNXI_CLK_FACTORS_H
 #define __MACH_SUNXI_CLK_FACTORS_H
 
diff --git a/drivers/clk/sunxi/clk-sun9i-cpus.c b/drivers/clk/sunxi/clk-sun9i-cpus.c
index 7626d2194b96..4d5e14142e15 100644
--- a/drivers/clk/sunxi/clk-sun9i-cpus.c
+++ b/drivers/clk/sunxi/clk-sun9i-cpus.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) 2015 Chen-Yu Tsai
  *
diff --git a/drivers/clk/tegra/Makefile b/drivers/clk/tegra/Makefile
index 4be8af28ee61..b71692391bd6 100644
--- a/drivers/clk/tegra/Makefile
+++ b/drivers/clk/tegra/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 obj-y					+= clk.o
 obj-y					+= clk-audio-sync.o
 obj-y					+= clk-dfll.o
diff --git a/drivers/clk/tegra/clk-id.h b/drivers/clk/tegra/clk-id.h
index 689f344377a7..11ee5f9ce99e 100644
--- a/drivers/clk/tegra/clk-id.h
+++ b/drivers/clk/tegra/clk-id.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * This header provides IDs for clocks common between several Tegra SoCs
  */
diff --git a/drivers/clk/ti/Makefile b/drivers/clk/ti/Makefile
index edb9f471e525..a2293ee09440 100644
--- a/drivers/clk/ti/Makefile
+++ b/drivers/clk/ti/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 ifeq ($(CONFIG_ARCH_OMAP2PLUS), y)
 
 obj-y					+= clk.o autoidle.o clockdomain.o
diff --git a/drivers/clk/uniphier/Makefile b/drivers/clk/uniphier/Makefile
index 665d1d65a90e..e5715abef180 100644
--- a/drivers/clk/uniphier/Makefile
+++ b/drivers/clk/uniphier/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 obj-y	+= clk-uniphier-core.o
 
 obj-y	+= clk-uniphier-cpugear.o
diff --git a/drivers/clk/ux500/Makefile b/drivers/clk/ux500/Makefile
index f3baef29859c..fedc083dc8be 100644
--- a/drivers/clk/ux500/Makefile
+++ b/drivers/clk/ux500/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 #
 # Makefile for ux500 clocks
 #
diff --git a/drivers/clk/versatile/clk-icst.h b/drivers/clk/versatile/clk-icst.h
index 5add02ebec5d..e36ca1a20e90 100644
--- a/drivers/clk/versatile/clk-icst.h
+++ b/drivers/clk/versatile/clk-icst.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /**
  * struct clk_icst_desc - descriptor for the ICST VCO
  * @params: ICST parameters