diff --git a/drivers/mtd/tests/mtd_subpagetest.c b/drivers/mtd/tests/mtd_subpagetest.c
new file mode 100644
index 0000000..4c5e04d
--- /dev/null
+++ b/drivers/mtd/tests/mtd_subpagetest.c
@@ -0,0 +1,525 @@
+/*
+ * Copyright (C) 2006-2007 Nokia Corporation
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; see the file COPYING. If not, write to the Free Software
+ * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Test sub-page read and write on MTD device.
+ * Author: Adrian Hunter <ext-adrian.hunter@nokia.com>
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/err.h>
+#include <linux/mtd/mtd.h>
+#include <linux/sched.h>
+
+#define PRINT_PREF KERN_INFO "mtd_subpagetest: "
+
+static int dev;
+module_param(dev, int, S_IRUGO);
+MODULE_PARM_DESC(dev, "MTD device number to use");
+
+static struct mtd_info *mtd;
+static unsigned char *writebuf;
+static unsigned char *readbuf;
+static unsigned char *bbt;
+
+static int subpgsize;
+static int bufsize;
+static int ebcnt;
+static int pgcnt;
+static int errcnt;
+static unsigned long next = 1;
+
+static inline unsigned int simple_rand(void)
+{
+	next = next * 1103515245 + 12345;
+	return (unsigned int)((next / 65536) % 32768);
+}
+
+static inline void simple_srand(unsigned long seed)
+{
+	next = seed;
+}
+
+static void set_random_data(unsigned char *buf, size_t len)
+{
+	size_t i;
+
+	for (i = 0; i < len; ++i)
+		buf[i] = simple_rand();
+}
+
+static inline void clear_data(unsigned char *buf, size_t len)
+{
+	memset(buf, 0, len);
+}
+
+static int erase_eraseblock(int ebnum)
+{
+	int err;
+	struct erase_info ei;
+	loff_t addr = ebnum * mtd->erasesize;
+
+	memset(&ei, 0, sizeof(struct erase_info));
+	ei.mtd  = mtd;
+	ei.addr = addr;
+	ei.len  = mtd->erasesize;
+
+	err = mtd->erase(mtd, &ei);
+	if (err) {
+		printk(PRINT_PREF "error %d while erasing EB %d\n", err, ebnum);
+		return err;
+	}
+
+	if (ei.state == MTD_ERASE_FAILED) {
+		printk(PRINT_PREF "some erase error occurred at EB %d\n",
+		       ebnum);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int erase_whole_device(void)
+{
+	int err;
+	unsigned int i;
+
+	printk(PRINT_PREF "erasing whole device\n");
+	for (i = 0; i < ebcnt; ++i) {
+		if (bbt[i])
+			continue;
+		err = erase_eraseblock(i);
+		if (err)
+			return err;
+		cond_resched();
+	}
+	printk(PRINT_PREF "erased %u eraseblocks\n", i);
+	return 0;
+}
+
+static int write_eraseblock(int ebnum)
+{
+	size_t written = 0;
+	int err = 0;
+	loff_t addr = ebnum * mtd->erasesize;
+
+	set_random_data(writebuf, subpgsize);
+	err = mtd->write(mtd, addr, subpgsize, &written, writebuf);
+	if (unlikely(err || written != subpgsize)) {
+		printk(PRINT_PREF "error: write failed at %#llx\n",
+		       (long long)addr);
+		if (written != subpgsize) {
+			printk(PRINT_PREF "  write size: %#x\n", subpgsize);
+			printk(PRINT_PREF "  written: %#x\n", written);
+		}
+		return err ? err : -1;
+	}
+
+	addr += subpgsize;
+
+	set_random_data(writebuf, subpgsize);
+	err = mtd->write(mtd, addr, subpgsize, &written, writebuf);
+	if (unlikely(err || written != subpgsize)) {
+		printk(PRINT_PREF "error: write failed at %#llx\n",
+		       (long long)addr);
+		if (written != subpgsize) {
+			printk(PRINT_PREF "  write size: %#x\n", subpgsize);
+			printk(PRINT_PREF "  written: %#x\n", written);
+		}
+		return err ? err : -1;
+	}
+
+	return err;
+}
+
+static int write_eraseblock2(int ebnum)
+{
+	size_t written = 0;
+	int err = 0, k;
+	loff_t addr = ebnum * mtd->erasesize;
+
+	for (k = 1; k < 33; ++k) {
+		if (addr + (subpgsize * k) > (ebnum + 1) * mtd->erasesize)
+			break;
+		set_random_data(writebuf, subpgsize * k);
+		err = mtd->write(mtd, addr, subpgsize * k, &written, writebuf);
+		if (unlikely(err || written != subpgsize * k)) {
+			printk(PRINT_PREF "error: write failed at %#llx\n",
+			       (long long)addr);
+			if (written != subpgsize) {
+				printk(PRINT_PREF "  write size: %#x\n",
+				       subpgsize * k);
+				printk(PRINT_PREF "  written: %#08x\n",
+				       written);
+			}
+			return err ? err : -1;
+		}
+		addr += subpgsize * k;
+	}
+
+	return err;
+}
+
+static void print_subpage(unsigned char *p)
+{
+	int i, j;
+
+	for (i = 0; i < subpgsize; ) {
+		for (j = 0; i < subpgsize && j < 32; ++i, ++j)
+			printk("%02x", *p++);
+		printk("\n");
+	}
+}
+
+static int verify_eraseblock(int ebnum)
+{
+	size_t read = 0;
+	int err = 0;
+	loff_t addr = ebnum * mtd->erasesize;
+
+	set_random_data(writebuf, subpgsize);
+	clear_data(readbuf, subpgsize);
+	read = 0;
+	err = mtd->read(mtd, addr, subpgsize, &read, readbuf);
+	if (unlikely(err || read != subpgsize)) {
+		if (err == -EUCLEAN && read == subpgsize) {
+			printk(PRINT_PREF "ECC correction at %#llx\n",
+			       (long long)addr);
+			err = 0;
+		} else {
+			printk(PRINT_PREF "error: read failed at %#llx\n",
+			       (long long)addr);
+			return err ? err : -1;
+		}
+	}
+	if (unlikely(memcmp(readbuf, writebuf, subpgsize))) {
+		printk(PRINT_PREF "error: verify failed at %#llx\n",
+		       (long long)addr);
+		printk(PRINT_PREF "------------- written----------------\n");
+		print_subpage(writebuf);
+		printk(PRINT_PREF "------------- read ------------------\n");
+		print_subpage(readbuf);
+		printk(PRINT_PREF "-------------------------------------\n");
+		errcnt += 1;
+	}
+
+	addr += subpgsize;
+
+	set_random_data(writebuf, subpgsize);
+	clear_data(readbuf, subpgsize);
+	read = 0;
+	err = mtd->read(mtd, addr, subpgsize, &read, readbuf);
+	if (unlikely(err || read != subpgsize)) {
+		if (err == -EUCLEAN && read == subpgsize) {
+			printk(PRINT_PREF "ECC correction at %#llx\n",
+			       (long long)addr);
+			err = 0;
+		} else {
+			printk(PRINT_PREF "error: read failed at %#llx\n",
+			       (long long)addr);
+			return err ? err : -1;
+		}
+	}
+	if (unlikely(memcmp(readbuf, writebuf, subpgsize))) {
+		printk(PRINT_PREF "error: verify failed at %#llx\n",
+		       (long long)addr);
+		printk(PRINT_PREF "------------- written----------------\n");
+		print_subpage(writebuf);
+		printk(PRINT_PREF "------------- read ------------------\n");
+		print_subpage(readbuf);
+		printk(PRINT_PREF "-------------------------------------\n");
+		errcnt += 1;
+	}
+
+	return err;
+}
+
+static int verify_eraseblock2(int ebnum)
+{
+	size_t read = 0;
+	int err = 0, k;
+	loff_t addr = ebnum * mtd->erasesize;
+
+	for (k = 1; k < 33; ++k) {
+		if (addr + (subpgsize * k) > (ebnum + 1) * mtd->erasesize)
+			break;
+		set_random_data(writebuf, subpgsize * k);
+		clear_data(readbuf, subpgsize * k);
+		read = 0;
+		err = mtd->read(mtd, addr, subpgsize * k, &read, readbuf);
+		if (unlikely(err || read != subpgsize * k)) {
+			if (err == -EUCLEAN && read == subpgsize * k) {
+				printk(PRINT_PREF "ECC correction at %#llx\n",
+				       (long long)addr);
+				err = 0;
+			} else {
+				printk(PRINT_PREF "error: read failed at "
+				       "%#llx\n", (long long)addr);
+				return err ? err : -1;
+			}
+		}
+		if (unlikely(memcmp(readbuf, writebuf, subpgsize * k))) {
+			printk(PRINT_PREF "error: verify failed at %#llx\n",
+			       (long long)addr);
+			errcnt += 1;
+		}
+		addr += subpgsize * k;
+	}
+
+	return err;
+}
+
+static int verify_eraseblock_ff(int ebnum)
+{
+	uint32_t j;
+	size_t read = 0;
+	int err = 0;
+	loff_t addr = ebnum * mtd->erasesize;
+
+	memset(writebuf, 0xff, subpgsize);
+	for (j = 0; j < mtd->erasesize / subpgsize; ++j) {
+		clear_data(readbuf, subpgsize);
+		read = 0;
+		err = mtd->read(mtd, addr, subpgsize, &read, readbuf);
+		if (unlikely(err || read != subpgsize)) {
+			if (err == -EUCLEAN && read == subpgsize) {
+				printk(PRINT_PREF "ECC correction at %#llx\n",
+				       (long long)addr);
+				err = 0;
+			} else {
+				printk(PRINT_PREF "error: read failed at "
+				       "%#llx\n", (long long)addr);
+				return err ? err : -1;
+			}
+		}
+		if (unlikely(memcmp(readbuf, writebuf, subpgsize))) {
+			printk(PRINT_PREF "error: verify 0xff failed at "
+			       "%#llx\n", (long long)addr);
+			errcnt += 1;
+		}
+		addr += subpgsize;
+	}
+
+	return err;
+}
+
+static int verify_all_eraseblocks_ff(void)
+{
+	int err;
+	unsigned int i;
+
+	printk(PRINT_PREF "verifying all eraseblocks for 0xff\n");
+	for (i = 0; i < ebcnt; ++i) {
+		if (bbt[i])
+			continue;
+		err = verify_eraseblock_ff(i);
+		if (err)
+			return err;
+		if (i % 256 == 0)
+			printk(PRINT_PREF "verified up to eraseblock %u\n", i);
+		cond_resched();
+	}
+	printk(PRINT_PREF "verified %u eraseblocks\n", i);
+	return 0;
+}
+
+static int is_block_bad(int ebnum)
+{
+	loff_t addr = ebnum * mtd->erasesize;
+	int ret;
+
+	ret = mtd->block_isbad(mtd, addr);
+	if (ret)
+		printk(PRINT_PREF "block %d is bad\n", ebnum);
+	return ret;
+}
+
+static int scan_for_bad_eraseblocks(void)
+{
+	int i, bad = 0;
+
+	bbt = kmalloc(ebcnt, GFP_KERNEL);
+	if (!bbt) {
+		printk(PRINT_PREF "error: cannot allocate memory\n");
+		return -ENOMEM;
+	}
+	memset(bbt, 0 , ebcnt);
+
+	printk(PRINT_PREF "scanning for bad eraseblocks\n");
+	for (i = 0; i < ebcnt; ++i) {
+		bbt[i] = is_block_bad(i) ? 1 : 0;
+		if (bbt[i])
+			bad += 1;
+		cond_resched();
+	}
+	printk(PRINT_PREF "scanned %d eraseblocks, %d are bad\n", i, bad);
+	return 0;
+}
+
+static int __init mtd_subpagetest_init(void)
+{
+	int err = 0;
+	uint32_t i;
+	uint64_t tmp;
+
+	printk(KERN_INFO "\n");
+	printk(KERN_INFO "=================================================\n");
+	printk(PRINT_PREF "MTD device: %d\n", dev);
+
+	mtd = get_mtd_device(NULL, dev);
+	if (IS_ERR(mtd)) {
+		err = PTR_ERR(mtd);
+		printk(PRINT_PREF "error: cannot get MTD device\n");
+		return err;
+	}
+
+	if (mtd->type != MTD_NANDFLASH) {
+		printk(PRINT_PREF "this test requires NAND flash\n");
+		goto out;
+	}
+
+	subpgsize = mtd->writesize >> mtd->subpage_sft;
+	printk(PRINT_PREF "MTD device size %llu, eraseblock size %u, "
+	       "page size %u, subpage size %u, count of eraseblocks %u, "
+	       "pages per eraseblock %u, OOB size %u\n",
+	       (unsigned long long)mtd->size, mtd->erasesize,
+	       mtd->writesize, subpgsize, ebcnt, pgcnt, mtd->oobsize);
+
+	err = -ENOMEM;
+	bufsize = subpgsize * 32;
+	writebuf = kmalloc(bufsize, GFP_KERNEL);
+	if (!writebuf) {
+		printk(PRINT_PREF "error: cannot allocate memory\n");
+		goto out;
+	}
+	readbuf = kmalloc(bufsize, GFP_KERNEL);
+	if (!readbuf) {
+		printk(PRINT_PREF "error: cannot allocate memory\n");
+		goto out;
+	}
+
+	tmp = mtd->size;
+	do_div(tmp, mtd->erasesize);
+	ebcnt = tmp;
+	pgcnt = mtd->erasesize / mtd->writesize;
+
+	err = scan_for_bad_eraseblocks();
+	if (err)
+		goto out;
+
+	err = erase_whole_device();
+	if (err)
+		goto out;
+
+	printk(PRINT_PREF "writing whole device\n");
+	simple_srand(1);
+	for (i = 0; i < ebcnt; ++i) {
+		if (bbt[i])
+			continue;
+		err = write_eraseblock(i);
+		if (unlikely(err))
+			goto out;
+		if (i % 256 == 0)
+			printk(PRINT_PREF "written up to eraseblock %u\n", i);
+		cond_resched();
+	}
+	printk(PRINT_PREF "written %u eraseblocks\n", i);
+
+	simple_srand(1);
+	printk(PRINT_PREF "verifying all eraseblocks\n");
+	for (i = 0; i < ebcnt; ++i) {
+		if (bbt[i])
+			continue;
+		err = verify_eraseblock(i);
+		if (unlikely(err))
+			goto out;
+		if (i % 256 == 0)
+			printk(PRINT_PREF "verified up to eraseblock %u\n", i);
+		cond_resched();
+	}
+	printk(PRINT_PREF "verified %u eraseblocks\n", i);
+
+	err = erase_whole_device();
+	if (err)
+		goto out;
+
+	err = verify_all_eraseblocks_ff();
+	if (err)
+		goto out;
+
+	/* Write all eraseblocks */
+	simple_srand(3);
+	printk(PRINT_PREF "writing whole device\n");
+	for (i = 0; i < ebcnt; ++i) {
+		if (bbt[i])
+			continue;
+		err = write_eraseblock2(i);
+		if (unlikely(err))
+			goto out;
+		if (i % 256 == 0)
+			printk(PRINT_PREF "written up to eraseblock %u\n", i);
+		cond_resched();
+	}
+	printk(PRINT_PREF "written %u eraseblocks\n", i);
+
+	/* Check all eraseblocks */
+	simple_srand(3);
+	printk(PRINT_PREF "verifying all eraseblocks\n");
+	for (i = 0; i < ebcnt; ++i) {
+		if (bbt[i])
+			continue;
+		err = verify_eraseblock2(i);
+		if (unlikely(err))
+			goto out;
+		if (i % 256 == 0)
+			printk(PRINT_PREF "verified up to eraseblock %u\n", i);
+		cond_resched();
+	}
+	printk(PRINT_PREF "verified %u eraseblocks\n", i);
+
+	err = erase_whole_device();
+	if (err)
+		goto out;
+
+	err = verify_all_eraseblocks_ff();
+	if (err)
+		goto out;
+
+	printk(PRINT_PREF "finished with %d errors\n", errcnt);
+
+out:
+	kfree(bbt);
+	kfree(readbuf);
+	kfree(writebuf);
+	put_mtd_device(mtd);
+	if (err)
+		printk(PRINT_PREF "error %d occurred\n", err);
+	printk(KERN_INFO "=================================================\n");
+	return err;
+}
+module_init(mtd_subpagetest_init);
+
+static void __exit mtd_subpagetest_exit(void)
+{
+	return;
+}
+module_exit(mtd_subpagetest_exit);
+
+MODULE_DESCRIPTION("Subpage test module");
+MODULE_AUTHOR("Adrian Hunter");
+MODULE_LICENSE("GPL");
