diff --git a/ap/os/linux/linux-3.4.x/lib/hexdump.c b/ap/os/linux/linux-3.4.x/lib/hexdump.c
new file mode 100644
index 0000000..6540d65
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/lib/hexdump.c
@@ -0,0 +1,249 @@
+/*
+ * lib/hexdump.c
+ *
+ * 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. See README and COPYING for
+ * more details.
+ */
+
+#include <linux/types.h>
+#include <linux/ctype.h>
+#include <linux/kernel.h>
+#include <linux/export.h>
+
+const char hex_asc[] = "0123456789abcdef";
+EXPORT_SYMBOL(hex_asc);
+
+/**
+ * hex_to_bin - convert a hex digit to its real value
+ * @ch: ascii character represents hex digit
+ *
+ * hex_to_bin() converts one hex digit to its actual value or -1 in case of bad
+ * input.
+ */
+int hex_to_bin(char ch)
+{
+	if ((ch >= '0') && (ch <= '9'))
+		return ch - '0';
+	ch = tolower(ch);
+	if ((ch >= 'a') && (ch <= 'f'))
+		return ch - 'a' + 10;
+	return -1;
+}
+EXPORT_SYMBOL(hex_to_bin);
+
+/**
+ * hex2bin - convert an ascii hexadecimal string to its binary representation
+ * @dst: binary result
+ * @src: ascii hexadecimal string
+ * @count: result length
+ *
+ * Return 0 on success, -1 in case of bad input.
+ */
+int hex2bin(u8 *dst, const char *src, size_t count)
+{
+	while (count--) {
+		int hi = hex_to_bin(*src++);
+		int lo = hex_to_bin(*src++);
+
+		if ((hi < 0) || (lo < 0))
+			return -1;
+
+		*dst++ = (hi << 4) | lo;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(hex2bin);
+
+/**
+ * hex_dump_to_buffer - convert a blob of data to "hex ASCII" in memory
+ * @buf: data blob to dump
+ * @len: number of bytes in the @buf
+ * @rowsize: number of bytes to print per line; must be 16 or 32
+ * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1)
+ * @linebuf: where to put the converted data
+ * @linebuflen: total size of @linebuf, including space for terminating NUL
+ * @ascii: include ASCII after the hex output
+ *
+ * hex_dump_to_buffer() works on one "line" of output at a time, i.e.,
+ * 16 or 32 bytes of input data converted to hex + ASCII output.
+ *
+ * Given a buffer of u8 data, hex_dump_to_buffer() converts the input data
+ * to a hex + ASCII dump at the supplied memory location.
+ * The converted output is always NUL-terminated.
+ *
+ * E.g.:
+ *   hex_dump_to_buffer(frame->data, frame->len, 16, 1,
+ *			linebuf, sizeof(linebuf), true);
+ *
+ * example output buffer:
+ * 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f  @ABCDEFGHIJKLMNO
+ */
+void hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
+			int groupsize, char *linebuf, size_t linebuflen,
+			bool ascii)
+{
+	const u8 *ptr = buf;
+	u8 ch;
+	int j, lx = 0;
+	int ascii_column;
+
+	if (rowsize != 16 && rowsize != 32)
+		rowsize = 16;
+
+	if (!len)
+		goto nil;
+	if (len > rowsize)		/* limit to one line at a time */
+		len = rowsize;
+	if ((len % groupsize) != 0)	/* no mixed size output */
+		groupsize = 1;
+
+	switch (groupsize) {
+	case 8: {
+		const u64 *ptr8 = buf;
+		int ngroups = len / groupsize;
+
+		for (j = 0; j < ngroups; j++)
+			lx += scnprintf(linebuf + lx, linebuflen - lx,
+					"%s%16.16llx", j ? " " : "",
+					(unsigned long long)*(ptr8 + j));
+		ascii_column = 17 * ngroups + 2;
+		break;
+	}
+
+	case 4: {
+		const u32 *ptr4 = buf;
+		int ngroups = len / groupsize;
+
+		for (j = 0; j < ngroups; j++)
+			lx += scnprintf(linebuf + lx, linebuflen - lx,
+					"%s%8.8x", j ? " " : "", *(ptr4 + j));
+		ascii_column = 9 * ngroups + 2;
+		break;
+	}
+
+	case 2: {
+		const u16 *ptr2 = buf;
+		int ngroups = len / groupsize;
+
+		for (j = 0; j < ngroups; j++)
+			lx += scnprintf(linebuf + lx, linebuflen - lx,
+					"%s%4.4x", j ? " " : "", *(ptr2 + j));
+		ascii_column = 5 * ngroups + 2;
+		break;
+	}
+
+	default:
+		for (j = 0; (j < len) && (lx + 3) <= linebuflen; j++) {
+			ch = ptr[j];
+			linebuf[lx++] = hex_asc_hi(ch);
+			linebuf[lx++] = hex_asc_lo(ch);
+			linebuf[lx++] = ' ';
+		}
+		if (j)
+			lx--;
+
+		ascii_column = 3 * rowsize + 2;
+		break;
+	}
+	if (!ascii)
+		goto nil;
+
+	while (lx < (linebuflen - 1) && lx < (ascii_column - 1))
+		linebuf[lx++] = ' ';
+	for (j = 0; (j < len) && (lx + 2) < linebuflen; j++) {
+		ch = ptr[j];
+		linebuf[lx++] = (isascii(ch) && isprint(ch)) ? ch : '.';
+	}
+nil:
+	linebuf[lx++] = '\0';
+}
+EXPORT_SYMBOL(hex_dump_to_buffer);
+
+#ifdef CONFIG_PRINTK
+/**
+ * print_hex_dump - print a text hex dump to syslog for a binary blob of data
+ * @level: kernel log level (e.g. KERN_DEBUG)
+ * @prefix_str: string to prefix each line with;
+ *  caller supplies trailing spaces for alignment if desired
+ * @prefix_type: controls whether prefix of an offset, address, or none
+ *  is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
+ * @rowsize: number of bytes to print per line; must be 16 or 32
+ * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1)
+ * @buf: data blob to dump
+ * @len: number of bytes in the @buf
+ * @ascii: include ASCII after the hex output
+ *
+ * Given a buffer of u8 data, print_hex_dump() prints a hex + ASCII dump
+ * to the kernel log at the specified kernel log level, with an optional
+ * leading prefix.
+ *
+ * print_hex_dump() works on one "line" of output at a time, i.e.,
+ * 16 or 32 bytes of input data converted to hex + ASCII output.
+ * print_hex_dump() iterates over the entire input @buf, breaking it into
+ * "line size" chunks to format and print.
+ *
+ * E.g.:
+ *   print_hex_dump(KERN_DEBUG, "raw data: ", DUMP_PREFIX_ADDRESS,
+ *		    16, 1, frame->data, frame->len, true);
+ *
+ * Example output using %DUMP_PREFIX_OFFSET and 1-byte mode:
+ * 0009ab42: 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f  @ABCDEFGHIJKLMNO
+ * Example output using %DUMP_PREFIX_ADDRESS and 4-byte mode:
+ * ffffffff88089af0: 73727170 77767574 7b7a7978 7f7e7d7c  pqrstuvwxyz{|}~.
+ */
+void print_hex_dump(const char *level, const char *prefix_str, int prefix_type,
+		    int rowsize, int groupsize,
+		    const void *buf, size_t len, bool ascii)
+{
+	const u8 *ptr = buf;
+	int i, linelen, remaining = len;
+	unsigned char linebuf[32 * 3 + 2 + 32 + 1];
+
+	if (rowsize != 16 && rowsize != 32)
+		rowsize = 16;
+
+	for (i = 0; i < len; i += rowsize) {
+		linelen = min(remaining, rowsize);
+		remaining -= rowsize;
+
+		hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize,
+				   linebuf, sizeof(linebuf), ascii);
+
+		switch (prefix_type) {
+		case DUMP_PREFIX_ADDRESS:
+			printk("%s%s%p: %s\n",
+			       level, prefix_str, ptr + i, linebuf);
+			break;
+		case DUMP_PREFIX_OFFSET:
+			printk("%s%s%.8x: %s\n", level, prefix_str, i, linebuf);
+			break;
+		default:
+			printk("%s%s%s\n", level, prefix_str, linebuf);
+			break;
+		}
+	}
+}
+EXPORT_SYMBOL(print_hex_dump);
+
+/**
+ * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params
+ * @prefix_str: string to prefix each line with;
+ *  caller supplies trailing spaces for alignment if desired
+ * @prefix_type: controls whether prefix of an offset, address, or none
+ *  is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
+ * @buf: data blob to dump
+ * @len: number of bytes in the @buf
+ *
+ * Calls print_hex_dump(), with log level of KERN_DEBUG,
+ * rowsize of 16, groupsize of 1, and ASCII output included.
+ */
+void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
+			  const void *buf, size_t len)
+{
+	print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, 16, 1,
+		       buf, len, true);
+}
+EXPORT_SYMBOL(print_hex_dump_bytes);
+#endif