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-rw-r--r--drivers/mtd/tests/oobtest.c750
1 files changed, 750 insertions, 0 deletions
diff --git a/drivers/mtd/tests/oobtest.c b/drivers/mtd/tests/oobtest.c
new file mode 100644
index 000000000..766b2c385
--- /dev/null
+++ b/drivers/mtd/tests/oobtest.c
@@ -0,0 +1,750 @@
+/*
+ * Copyright (C) 2006-2008 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 OOB read and write on MTD device.
+ *
+ * Author: Adrian Hunter <ext-adrian.hunter@nokia.com>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <asm/div64.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/err.h>
+#include <linux/mtd/mtd.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/random.h>
+
+#include "mtd_test.h"
+
+static int dev = -EINVAL;
+static int bitflip_limit;
+module_param(dev, int, S_IRUGO);
+MODULE_PARM_DESC(dev, "MTD device number to use");
+module_param(bitflip_limit, int, S_IRUGO);
+MODULE_PARM_DESC(bitflip_limit, "Max. allowed bitflips per page");
+
+static struct mtd_info *mtd;
+static unsigned char *readbuf;
+static unsigned char *writebuf;
+static unsigned char *bbt;
+
+static int ebcnt;
+static int pgcnt;
+static int errcnt;
+static int use_offset;
+static int use_len;
+static int use_len_max;
+static int vary_offset;
+static struct rnd_state rnd_state;
+
+static void do_vary_offset(void)
+{
+ use_len -= 1;
+ if (use_len < 1) {
+ use_offset += 1;
+ if (use_offset >= use_len_max)
+ use_offset = 0;
+ use_len = use_len_max - use_offset;
+ }
+}
+
+static int write_eraseblock(int ebnum)
+{
+ int i;
+ struct mtd_oob_ops ops;
+ int err = 0;
+ loff_t addr = (loff_t)ebnum * mtd->erasesize;
+
+ prandom_bytes_state(&rnd_state, writebuf, use_len_max * pgcnt);
+ for (i = 0; i < pgcnt; ++i, addr += mtd->writesize) {
+ ops.mode = MTD_OPS_AUTO_OOB;
+ ops.len = 0;
+ ops.retlen = 0;
+ ops.ooblen = use_len;
+ ops.oobretlen = 0;
+ ops.ooboffs = use_offset;
+ ops.datbuf = NULL;
+ ops.oobbuf = writebuf + (use_len_max * i) + use_offset;
+ err = mtd_write_oob(mtd, addr, &ops);
+ if (err || ops.oobretlen != use_len) {
+ pr_err("error: writeoob failed at %#llx\n",
+ (long long)addr);
+ pr_err("error: use_len %d, use_offset %d\n",
+ use_len, use_offset);
+ errcnt += 1;
+ return err ? err : -1;
+ }
+ if (vary_offset)
+ do_vary_offset();
+ }
+
+ return err;
+}
+
+static int write_whole_device(void)
+{
+ int err;
+ unsigned int i;
+
+ pr_info("writing OOBs of whole device\n");
+ for (i = 0; i < ebcnt; ++i) {
+ if (bbt[i])
+ continue;
+ err = write_eraseblock(i);
+ if (err)
+ return err;
+ if (i % 256 == 0)
+ pr_info("written up to eraseblock %u\n", i);
+
+ err = mtdtest_relax();
+ if (err)
+ return err;
+ }
+ pr_info("written %u eraseblocks\n", i);
+ return 0;
+}
+
+/*
+ * Display the address, offset and data bytes at comparison failure.
+ * Return number of bitflips encountered.
+ */
+static size_t memcmpshowoffset(loff_t addr, loff_t offset, const void *cs,
+ const void *ct, size_t count)
+{
+ const unsigned char *su1, *su2;
+ int res;
+ size_t i = 0;
+ size_t bitflips = 0;
+
+ for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--, i++) {
+ res = *su1 ^ *su2;
+ if (res) {
+ pr_info("error @addr[0x%lx:0x%lx] 0x%x -> 0x%x diff 0x%x\n",
+ (unsigned long)addr, (unsigned long)offset + i,
+ *su1, *su2, res);
+ bitflips += hweight8(res);
+ }
+ }
+
+ return bitflips;
+}
+
+#define memcmpshow(addr, cs, ct, count) memcmpshowoffset((addr), 0, (cs), (ct),\
+ (count))
+
+/*
+ * Compare with 0xff and show the address, offset and data bytes at
+ * comparison failure. Return number of bitflips encountered.
+ */
+static size_t memffshow(loff_t addr, loff_t offset, const void *cs,
+ size_t count)
+{
+ const unsigned char *su1;
+ int res;
+ size_t i = 0;
+ size_t bitflips = 0;
+
+ for (su1 = cs; 0 < count; ++su1, count--, i++) {
+ res = *su1 ^ 0xff;
+ if (res) {
+ pr_info("error @addr[0x%lx:0x%lx] 0x%x -> 0xff diff 0x%x\n",
+ (unsigned long)addr, (unsigned long)offset + i,
+ *su1, res);
+ bitflips += hweight8(res);
+ }
+ }
+
+ return bitflips;
+}
+
+static int verify_eraseblock(int ebnum)
+{
+ int i;
+ struct mtd_oob_ops ops;
+ int err = 0;
+ loff_t addr = (loff_t)ebnum * mtd->erasesize;
+ size_t bitflips;
+
+ prandom_bytes_state(&rnd_state, writebuf, use_len_max * pgcnt);
+ for (i = 0; i < pgcnt; ++i, addr += mtd->writesize) {
+ ops.mode = MTD_OPS_AUTO_OOB;
+ ops.len = 0;
+ ops.retlen = 0;
+ ops.ooblen = use_len;
+ ops.oobretlen = 0;
+ ops.ooboffs = use_offset;
+ ops.datbuf = NULL;
+ ops.oobbuf = readbuf;
+ err = mtd_read_oob(mtd, addr, &ops);
+ if (mtd_is_bitflip(err))
+ err = 0;
+
+ if (err || ops.oobretlen != use_len) {
+ pr_err("error: readoob failed at %#llx\n",
+ (long long)addr);
+ errcnt += 1;
+ return err ? err : -1;
+ }
+
+ bitflips = memcmpshow(addr, readbuf,
+ writebuf + (use_len_max * i) + use_offset,
+ use_len);
+ if (bitflips > bitflip_limit) {
+ pr_err("error: verify failed at %#llx\n",
+ (long long)addr);
+ errcnt += 1;
+ if (errcnt > 1000) {
+ pr_err("error: too many errors\n");
+ return -1;
+ }
+ } else if (bitflips) {
+ pr_info("ignoring error as within bitflip_limit\n");
+ }
+
+ if (use_offset != 0 || use_len < mtd->oobavail) {
+ int k;
+
+ ops.mode = MTD_OPS_AUTO_OOB;
+ ops.len = 0;
+ ops.retlen = 0;
+ ops.ooblen = mtd->oobavail;
+ ops.oobretlen = 0;
+ ops.ooboffs = 0;
+ ops.datbuf = NULL;
+ ops.oobbuf = readbuf;
+ err = mtd_read_oob(mtd, addr, &ops);
+ if (mtd_is_bitflip(err))
+ err = 0;
+
+ if (err || ops.oobretlen != mtd->oobavail) {
+ pr_err("error: readoob failed at %#llx\n",
+ (long long)addr);
+ errcnt += 1;
+ return err ? err : -1;
+ }
+ bitflips = memcmpshowoffset(addr, use_offset,
+ readbuf + use_offset,
+ writebuf + (use_len_max * i) + use_offset,
+ use_len);
+
+ /* verify pre-offset area for 0xff */
+ bitflips += memffshow(addr, 0, readbuf, use_offset);
+
+ /* verify post-(use_offset + use_len) area for 0xff */
+ k = use_offset + use_len;
+ bitflips += memffshow(addr, k, readbuf + k,
+ mtd->oobavail - k);
+
+ if (bitflips > bitflip_limit) {
+ pr_err("error: verify failed at %#llx\n",
+ (long long)addr);
+ errcnt += 1;
+ if (errcnt > 1000) {
+ pr_err("error: too many errors\n");
+ return -1;
+ }
+ } else if (bitflips) {
+ pr_info("ignoring errors as within bitflip limit\n");
+ }
+ }
+ if (vary_offset)
+ do_vary_offset();
+ }
+ return err;
+}
+
+static int verify_eraseblock_in_one_go(int ebnum)
+{
+ struct mtd_oob_ops ops;
+ int err = 0;
+ loff_t addr = (loff_t)ebnum * mtd->erasesize;
+ size_t len = mtd->oobavail * pgcnt;
+ size_t oobavail = mtd->oobavail;
+ size_t bitflips;
+ int i;
+
+ prandom_bytes_state(&rnd_state, writebuf, len);
+ ops.mode = MTD_OPS_AUTO_OOB;
+ ops.len = 0;
+ ops.retlen = 0;
+ ops.ooblen = len;
+ ops.oobretlen = 0;
+ ops.ooboffs = 0;
+ ops.datbuf = NULL;
+ ops.oobbuf = readbuf;
+
+ /* read entire block's OOB at one go */
+ err = mtd_read_oob(mtd, addr, &ops);
+ if (mtd_is_bitflip(err))
+ err = 0;
+
+ if (err || ops.oobretlen != len) {
+ pr_err("error: readoob failed at %#llx\n",
+ (long long)addr);
+ errcnt += 1;
+ return err ? err : -1;
+ }
+
+ /* verify one page OOB at a time for bitflip per page limit check */
+ for (i = 0; i < pgcnt; ++i, addr += mtd->writesize) {
+ bitflips = memcmpshow(addr, readbuf + (i * oobavail),
+ writebuf + (i * oobavail), oobavail);
+ if (bitflips > bitflip_limit) {
+ pr_err("error: verify failed at %#llx\n",
+ (long long)addr);
+ errcnt += 1;
+ if (errcnt > 1000) {
+ pr_err("error: too many errors\n");
+ return -1;
+ }
+ } else if (bitflips) {
+ pr_info("ignoring error as within bitflip_limit\n");
+ }
+ }
+
+ return err;
+}
+
+static int verify_all_eraseblocks(void)
+{
+ int err;
+ unsigned int i;
+
+ pr_info("verifying all eraseblocks\n");
+ for (i = 0; i < ebcnt; ++i) {
+ if (bbt[i])
+ continue;
+ err = verify_eraseblock(i);
+ if (err)
+ return err;
+ if (i % 256 == 0)
+ pr_info("verified up to eraseblock %u\n", i);
+
+ err = mtdtest_relax();
+ if (err)
+ return err;
+ }
+ pr_info("verified %u eraseblocks\n", i);
+ return 0;
+}
+
+static int __init mtd_oobtest_init(void)
+{
+ int err = 0;
+ unsigned int i;
+ uint64_t tmp;
+ struct mtd_oob_ops ops;
+ loff_t addr = 0, addr0;
+
+ printk(KERN_INFO "\n");
+ printk(KERN_INFO "=================================================\n");
+
+ if (dev < 0) {
+ pr_info("Please specify a valid mtd-device via module parameter\n");
+ pr_crit("CAREFUL: This test wipes all data on the specified MTD device!\n");
+ return -EINVAL;
+ }
+
+ pr_info("MTD device: %d\n", dev);
+
+ mtd = get_mtd_device(NULL, dev);
+ if (IS_ERR(mtd)) {
+ err = PTR_ERR(mtd);
+ pr_err("error: cannot get MTD device\n");
+ return err;
+ }
+
+ if (!mtd_type_is_nand(mtd)) {
+ pr_info("this test requires NAND flash\n");
+ goto out;
+ }
+
+ tmp = mtd->size;
+ do_div(tmp, mtd->erasesize);
+ ebcnt = tmp;
+ pgcnt = mtd->erasesize / mtd->writesize;
+
+ pr_info("MTD device size %llu, eraseblock size %u, "
+ "page size %u, count of eraseblocks %u, pages per "
+ "eraseblock %u, OOB size %u\n",
+ (unsigned long long)mtd->size, mtd->erasesize,
+ mtd->writesize, ebcnt, pgcnt, mtd->oobsize);
+
+ err = -ENOMEM;
+ readbuf = kmalloc(mtd->erasesize, GFP_KERNEL);
+ if (!readbuf)
+ goto out;
+ writebuf = kmalloc(mtd->erasesize, GFP_KERNEL);
+ if (!writebuf)
+ goto out;
+ bbt = kzalloc(ebcnt, GFP_KERNEL);
+ if (!bbt)
+ goto out;
+
+ err = mtdtest_scan_for_bad_eraseblocks(mtd, bbt, 0, ebcnt);
+ if (err)
+ goto out;
+
+ use_offset = 0;
+ use_len = mtd->oobavail;
+ use_len_max = mtd->oobavail;
+ vary_offset = 0;
+
+ /* First test: write all OOB, read it back and verify */
+ pr_info("test 1 of 5\n");
+
+ err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt);
+ if (err)
+ goto out;
+
+ prandom_seed_state(&rnd_state, 1);
+ err = write_whole_device();
+ if (err)
+ goto out;
+
+ prandom_seed_state(&rnd_state, 1);
+ err = verify_all_eraseblocks();
+ if (err)
+ goto out;
+
+ /*
+ * Second test: write all OOB, a block at a time, read it back and
+ * verify.
+ */
+ pr_info("test 2 of 5\n");
+
+ err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt);
+ if (err)
+ goto out;
+
+ prandom_seed_state(&rnd_state, 3);
+ err = write_whole_device();
+ if (err)
+ goto out;
+
+ /* Check all eraseblocks */
+ prandom_seed_state(&rnd_state, 3);
+ pr_info("verifying all eraseblocks\n");
+ for (i = 0; i < ebcnt; ++i) {
+ if (bbt[i])
+ continue;
+ err = verify_eraseblock_in_one_go(i);
+ if (err)
+ goto out;
+ if (i % 256 == 0)
+ pr_info("verified up to eraseblock %u\n", i);
+
+ err = mtdtest_relax();
+ if (err)
+ goto out;
+ }
+ pr_info("verified %u eraseblocks\n", i);
+
+ /*
+ * Third test: write OOB at varying offsets and lengths, read it back
+ * and verify.
+ */
+ pr_info("test 3 of 5\n");
+
+ err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt);
+ if (err)
+ goto out;
+
+ /* Write all eraseblocks */
+ use_offset = 0;
+ use_len = mtd->oobavail;
+ use_len_max = mtd->oobavail;
+ vary_offset = 1;
+ prandom_seed_state(&rnd_state, 5);
+
+ err = write_whole_device();
+ if (err)
+ goto out;
+
+ /* Check all eraseblocks */
+ use_offset = 0;
+ use_len = mtd->oobavail;
+ use_len_max = mtd->oobavail;
+ vary_offset = 1;
+ prandom_seed_state(&rnd_state, 5);
+ err = verify_all_eraseblocks();
+ if (err)
+ goto out;
+
+ use_offset = 0;
+ use_len = mtd->oobavail;
+ use_len_max = mtd->oobavail;
+ vary_offset = 0;
+
+ /* Fourth test: try to write off end of device */
+ pr_info("test 4 of 5\n");
+
+ err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt);
+ if (err)
+ goto out;
+
+ addr0 = 0;
+ for (i = 0; i < ebcnt && bbt[i]; ++i)
+ addr0 += mtd->erasesize;
+
+ /* Attempt to write off end of OOB */
+ ops.mode = MTD_OPS_AUTO_OOB;
+ ops.len = 0;
+ ops.retlen = 0;
+ ops.ooblen = 1;
+ ops.oobretlen = 0;
+ ops.ooboffs = mtd->oobavail;
+ ops.datbuf = NULL;
+ ops.oobbuf = writebuf;
+ pr_info("attempting to start write past end of OOB\n");
+ pr_info("an error is expected...\n");
+ err = mtd_write_oob(mtd, addr0, &ops);
+ if (err) {
+ pr_info("error occurred as expected\n");
+ err = 0;
+ } else {
+ pr_err("error: can write past end of OOB\n");
+ errcnt += 1;
+ }
+
+ /* Attempt to read off end of OOB */
+ ops.mode = MTD_OPS_AUTO_OOB;
+ ops.len = 0;
+ ops.retlen = 0;
+ ops.ooblen = 1;
+ ops.oobretlen = 0;
+ ops.ooboffs = mtd->oobavail;
+ ops.datbuf = NULL;
+ ops.oobbuf = readbuf;
+ pr_info("attempting to start read past end of OOB\n");
+ pr_info("an error is expected...\n");
+ err = mtd_read_oob(mtd, addr0, &ops);
+ if (mtd_is_bitflip(err))
+ err = 0;
+
+ if (err) {
+ pr_info("error occurred as expected\n");
+ err = 0;
+ } else {
+ pr_err("error: can read past end of OOB\n");
+ errcnt += 1;
+ }
+
+ if (bbt[ebcnt - 1])
+ pr_info("skipping end of device tests because last "
+ "block is bad\n");
+ else {
+ /* Attempt to write off end of device */
+ ops.mode = MTD_OPS_AUTO_OOB;
+ ops.len = 0;
+ ops.retlen = 0;
+ ops.ooblen = mtd->oobavail + 1;
+ ops.oobretlen = 0;
+ ops.ooboffs = 0;
+ ops.datbuf = NULL;
+ ops.oobbuf = writebuf;
+ pr_info("attempting to write past end of device\n");
+ pr_info("an error is expected...\n");
+ err = mtd_write_oob(mtd, mtd->size - mtd->writesize, &ops);
+ if (err) {
+ pr_info("error occurred as expected\n");
+ err = 0;
+ } else {
+ pr_err("error: wrote past end of device\n");
+ errcnt += 1;
+ }
+
+ /* Attempt to read off end of device */
+ ops.mode = MTD_OPS_AUTO_OOB;
+ ops.len = 0;
+ ops.retlen = 0;
+ ops.ooblen = mtd->oobavail + 1;
+ ops.oobretlen = 0;
+ ops.ooboffs = 0;
+ ops.datbuf = NULL;
+ ops.oobbuf = readbuf;
+ pr_info("attempting to read past end of device\n");
+ pr_info("an error is expected...\n");
+ err = mtd_read_oob(mtd, mtd->size - mtd->writesize, &ops);
+ if (mtd_is_bitflip(err))
+ err = 0;
+
+ if (err) {
+ pr_info("error occurred as expected\n");
+ err = 0;
+ } else {
+ pr_err("error: read past end of device\n");
+ errcnt += 1;
+ }
+
+ err = mtdtest_erase_eraseblock(mtd, ebcnt - 1);
+ if (err)
+ goto out;
+
+ /* Attempt to write off end of device */
+ ops.mode = MTD_OPS_AUTO_OOB;
+ ops.len = 0;
+ ops.retlen = 0;
+ ops.ooblen = mtd->oobavail;
+ ops.oobretlen = 0;
+ ops.ooboffs = 1;
+ ops.datbuf = NULL;
+ ops.oobbuf = writebuf;
+ pr_info("attempting to write past end of device\n");
+ pr_info("an error is expected...\n");
+ err = mtd_write_oob(mtd, mtd->size - mtd->writesize, &ops);
+ if (err) {
+ pr_info("error occurred as expected\n");
+ err = 0;
+ } else {
+ pr_err("error: wrote past end of device\n");
+ errcnt += 1;
+ }
+
+ /* Attempt to read off end of device */
+ ops.mode = MTD_OPS_AUTO_OOB;
+ ops.len = 0;
+ ops.retlen = 0;
+ ops.ooblen = mtd->oobavail;
+ ops.oobretlen = 0;
+ ops.ooboffs = 1;
+ ops.datbuf = NULL;
+ ops.oobbuf = readbuf;
+ pr_info("attempting to read past end of device\n");
+ pr_info("an error is expected...\n");
+ err = mtd_read_oob(mtd, mtd->size - mtd->writesize, &ops);
+ if (mtd_is_bitflip(err))
+ err = 0;
+
+ if (err) {
+ pr_info("error occurred as expected\n");
+ err = 0;
+ } else {
+ pr_err("error: read past end of device\n");
+ errcnt += 1;
+ }
+ }
+
+ /* Fifth test: write / read across block boundaries */
+ pr_info("test 5 of 5\n");
+
+ /* Erase all eraseblocks */
+ err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt);
+ if (err)
+ goto out;
+
+ /* Write all eraseblocks */
+ prandom_seed_state(&rnd_state, 11);
+ pr_info("writing OOBs of whole device\n");
+ for (i = 0; i < ebcnt - 1; ++i) {
+ int cnt = 2;
+ int pg;
+ size_t sz = mtd->oobavail;
+ if (bbt[i] || bbt[i + 1])
+ continue;
+ addr = (loff_t)(i + 1) * mtd->erasesize - mtd->writesize;
+ prandom_bytes_state(&rnd_state, writebuf, sz * cnt);
+ for (pg = 0; pg < cnt; ++pg) {
+ ops.mode = MTD_OPS_AUTO_OOB;
+ ops.len = 0;
+ ops.retlen = 0;
+ ops.ooblen = sz;
+ ops.oobretlen = 0;
+ ops.ooboffs = 0;
+ ops.datbuf = NULL;
+ ops.oobbuf = writebuf + pg * sz;
+ err = mtd_write_oob(mtd, addr, &ops);
+ if (err)
+ goto out;
+ if (i % 256 == 0)
+ pr_info("written up to eraseblock %u\n", i);
+
+ err = mtdtest_relax();
+ if (err)
+ goto out;
+
+ addr += mtd->writesize;
+ }
+ }
+ pr_info("written %u eraseblocks\n", i);
+
+ /* Check all eraseblocks */
+ prandom_seed_state(&rnd_state, 11);
+ pr_info("verifying all eraseblocks\n");
+ for (i = 0; i < ebcnt - 1; ++i) {
+ if (bbt[i] || bbt[i + 1])
+ continue;
+ prandom_bytes_state(&rnd_state, writebuf, mtd->oobavail * 2);
+ addr = (loff_t)(i + 1) * mtd->erasesize - mtd->writesize;
+ ops.mode = MTD_OPS_AUTO_OOB;
+ ops.len = 0;
+ ops.retlen = 0;
+ ops.ooblen = mtd->oobavail * 2;
+ ops.oobretlen = 0;
+ ops.ooboffs = 0;
+ ops.datbuf = NULL;
+ ops.oobbuf = readbuf;
+ err = mtd_read_oob(mtd, addr, &ops);
+ if (mtd_is_bitflip(err))
+ err = 0;
+
+ if (err)
+ goto out;
+ if (memcmpshow(addr, readbuf, writebuf,
+ mtd->oobavail * 2)) {
+ pr_err("error: verify failed at %#llx\n",
+ (long long)addr);
+ errcnt += 1;
+ if (errcnt > 1000) {
+ pr_err("error: too many errors\n");
+ goto out;
+ }
+ }
+ if (i % 256 == 0)
+ pr_info("verified up to eraseblock %u\n", i);
+
+ err = mtdtest_relax();
+ if (err)
+ goto out;
+ }
+ pr_info("verified %u eraseblocks\n", i);
+
+ pr_info("finished with %d errors\n", errcnt);
+out:
+ kfree(bbt);
+ kfree(writebuf);
+ kfree(readbuf);
+ put_mtd_device(mtd);
+ if (err)
+ pr_info("error %d occurred\n", err);
+ printk(KERN_INFO "=================================================\n");
+ return err;
+}
+module_init(mtd_oobtest_init);
+
+static void __exit mtd_oobtest_exit(void)
+{
+ return;
+}
+module_exit(mtd_oobtest_exit);
+
+MODULE_DESCRIPTION("Out-of-band test module");
+MODULE_AUTHOR("Adrian Hunter");
+MODULE_LICENSE("GPL");