diff --git a/drivers/mmc/core/debugfs.c b/drivers/mmc/core/debugfs.c
index 1237bb4..610dbd1 100644
--- a/drivers/mmc/core/debugfs.c
+++ b/drivers/mmc/core/debugfs.c
@@ -184,6 +184,68 @@
 DEFINE_SIMPLE_ATTRIBUTE(mmc_dbg_card_status_fops, mmc_dbg_card_status_get,
 		NULL, "%08llx\n");
 
+#define EXT_CSD_STR_LEN 1025
+
+static int mmc_ext_csd_open(struct inode *inode, struct file *filp)
+{
+	struct mmc_card *card = inode->i_private;
+	char *buf;
+	ssize_t n = 0;
+	u8 *ext_csd;
+	int err, i;
+
+	buf = kmalloc(EXT_CSD_STR_LEN + 1, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ext_csd = kmalloc(512, GFP_KERNEL);
+	if (!ext_csd) {
+		err = -ENOMEM;
+		goto out_free;
+	}
+
+	mmc_claim_host(card->host);
+	err = mmc_send_ext_csd(card, ext_csd);
+	mmc_release_host(card->host);
+	if (err)
+		goto out_free;
+
+	for (i = 511; i >= 0; i--)
+		n += sprintf(buf + n, "%02x", ext_csd[i]);
+	n += sprintf(buf + n, "\n");
+	BUG_ON(n != EXT_CSD_STR_LEN);
+
+	filp->private_data = buf;
+	kfree(ext_csd);
+	return 0;
+
+out_free:
+	kfree(buf);
+	kfree(ext_csd);
+	return err;
+}
+
+static ssize_t mmc_ext_csd_read(struct file *filp, char __user *ubuf,
+				size_t cnt, loff_t *ppos)
+{
+	char *buf = filp->private_data;
+
+	return simple_read_from_buffer(ubuf, cnt, ppos,
+				       buf, EXT_CSD_STR_LEN);
+}
+
+static int mmc_ext_csd_release(struct inode *inode, struct file *file)
+{
+	kfree(file->private_data);
+	return 0;
+}
+
+static struct file_operations mmc_dbg_ext_csd_fops = {
+	.open		= mmc_ext_csd_open,
+	.read		= mmc_ext_csd_read,
+	.release	= mmc_ext_csd_release,
+};
+
 void mmc_add_card_debugfs(struct mmc_card *card)
 {
 	struct mmc_host	*host = card->host;
@@ -211,6 +273,11 @@
 					&mmc_dbg_card_status_fops))
 			goto err;
 
+	if (mmc_card_mmc(card))
+		if (!debugfs_create_file("ext_csd", S_IRUSR, root, card,
+					&mmc_dbg_ext_csd_fops))
+			goto err;
+
 	return;
 
 err: