ar71xx: Add kernel 4.9 support

This add support for kernel 4.9 to the ar71xx target.
It was compile tested with the generic, NAND and mikrotik subtarget.
Multiple members of the community tested it on their boards and did not
report any major problem so far.

Especially the NAND part received some changes to adapt to the new
kernel APIs. The serial driver hack used for the Arduino Yun was not
ported because the kernel changed there a lot.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

1 files changed, 124 insertions, 0 deletions

diff --git a/target/linux/ar71xx/patches-4.9/310-lib-add-rle-decompression.patch b/target/linux/ar71xx/patches-4.9/310-lib-add-rle-decompression.patch
new file mode 100644
index 0000000000..d8480125a9
--- /dev/null
+++ b/target/linux/ar71xx/patches-4.9/310-lib-add-rle-decompression.patch
@@ -0,0 +1,124 @@
+--- a/lib/Kconfig
++++ b/lib/Kconfig
+@@ -247,6 +247,9 @@ config LZMA_COMPRESS
+ config LZMA_DECOMPRESS
+     tristate
+ 
++config RLE_DECOMPRESS
++	tristate
++
+ #
+ # These all provide a common interface (hence the apparent duplication with
+ # ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
+--- a/lib/Makefile
++++ b/lib/Makefile
+@@ -120,6 +120,7 @@ obj-$(CONFIG_XZ_DEC) += xz/
+ obj-$(CONFIG_RAID6_PQ) += raid6/
+ obj-$(CONFIG_LZMA_COMPRESS) += lzma/
+ obj-$(CONFIG_LZMA_DECOMPRESS) += lzma/
++obj-$(CONFIG_RLE_DECOMPRESS) += rle.o
+ 
+ lib-$(CONFIG_DECOMPRESS_GZIP) += decompress_inflate.o
+ lib-$(CONFIG_DECOMPRESS_BZIP2) += decompress_bunzip2.o
+--- /dev/null
++++ b/include/linux/rle.h
+@@ -0,0 +1,18 @@
++#ifndef _RLE_H_
++#define _RLE_H_
++
++#ifdef CONFIG_RLE_DECOMPRESS
++int rle_decode(const unsigned char *src, size_t srclen,
++	       unsigned char *dst, size_t dstlen,
++	       size_t *src_done, size_t *dst_done);
++#else
++static inline int
++rle_decode(const unsigned char *src, size_t srclen,
++	   unsigned char *dst, size_t dstlen,
++	   size_t *src_done, size_t *dst_done)
++{
++	return -ENOTSUPP;
++}
++#endif /* CONFIG_RLE_DECOMPRESS */
++
++#endif /* _RLE_H_ */
+--- /dev/null
++++ b/lib/rle.c
+@@ -0,0 +1,78 @@
++/*
++ *  RLE decoding routine
++ *
++ *  Copyright (C) 2012 Gabor Juhos <juhosg@openwrt.org>
++ *
++ *  This program is free software; you can redistribute it and/or modify it
++ *  under the terms of the GNU General Public License version 2 as published
++ *  by the Free Software Foundation.
++ */
++
++#include <linux/kernel.h>
++#include <linux/module.h>
++#include <linux/rle.h>
++
++int rle_decode(const unsigned char *src, size_t srclen,
++	       unsigned char *dst, size_t dstlen,
++	       size_t *src_done, size_t *dst_done)
++{
++	size_t srcpos, dstpos;
++	int ret;
++
++	srcpos = 0;
++	dstpos = 0;
++	ret = -EINVAL;
++
++	/* sanity checks */
++	if (!src || !srclen || !dst || !dstlen)
++		goto out;
++
++	while (1) {
++		char count;
++
++		if (srcpos >= srclen)
++			break;
++
++		count = (char) src[srcpos++];
++		if (count == 0) {
++			ret = 0;
++			break;
++		}
++
++		if (count > 0) {
++			unsigned char c;
++
++			if (srcpos >= srclen)
++				break;
++
++			c = src[srcpos++];
++
++			while (count--) {
++				if (dstpos >= dstlen)
++					break;
++
++				dst[dstpos++] = c;
++			}
++		} else {
++			count *= -1;
++
++			while (count--) {
++				if (srcpos >= srclen)
++					break;
++				if (dstpos >= dstlen)
++					break;
++				dst[dstpos++] = src[srcpos++];
++			}
++		}
++	}
++
++out:
++	if (src_done)
++		*src_done = srcpos;
++	if (dst_done)
++		*dst_done = dstpos;
++
++	return ret;
++}
++
++EXPORT_SYMBOL_GPL(rle_decode);