From: Pierre Ossman <drzeus@drzeus.cx>
Date: Sun, 22 Jul 2007 22:34:07 +0000 (+0200)
Subject: mmc: read ext_csd version number
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d7604d76351f7745d0e62d9f2bbcbb917c9013f3;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git

mmc: read ext_csd version number

Make sure we do not try to parse a structure we do not
understand.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
---

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 258fe73eeaa7..cdc38b43b799 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -161,6 +161,7 @@ static int mmc_read_ext_csd(struct mmc_card *card)
 {
 	int err;
 	u8 *ext_csd;
+	unsigned int ext_csd_struct;
 
 	BUG_ON(!card);
 
@@ -209,13 +210,22 @@ static int mmc_read_ext_csd(struct mmc_card *card)
 		goto out;
 	}
 
-	card->ext_csd.sectors =
-		ext_csd[EXT_CSD_SEC_CNT + 0] << 0 |
-		ext_csd[EXT_CSD_SEC_CNT + 1] << 8 |
-		ext_csd[EXT_CSD_SEC_CNT + 2] << 16 |
-		ext_csd[EXT_CSD_SEC_CNT + 3] << 24;
-	if (card->ext_csd.sectors)
-		mmc_card_set_blockaddr(card);
+	ext_csd_struct = ext_csd[EXT_CSD_REV];
+	if (ext_csd_struct > 2) {
+		printk("%s: unrecognised EXT_CSD structure version %d\n",
+			mmc_hostname(card->host), ext_csd_struct);
+		return -EINVAL;
+	}
+
+	if (ext_csd_struct >= 2) {
+		card->ext_csd.sectors =
+			ext_csd[EXT_CSD_SEC_CNT + 0] << 0 |
+			ext_csd[EXT_CSD_SEC_CNT + 1] << 8 |
+			ext_csd[EXT_CSD_SEC_CNT + 2] << 16 |
+			ext_csd[EXT_CSD_SEC_CNT + 3] << 24;
+		if (card->ext_csd.sectors)
+			mmc_card_set_blockaddr(card);
+	}
 
 	switch (ext_csd[EXT_CSD_CARD_TYPE]) {
 	case EXT_CSD_CARD_TYPE_52 | EXT_CSD_CARD_TYPE_26:
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index e3ed9b95040e..d1d6cbcc1514 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -227,6 +227,7 @@ struct _mmc_csd {
 #define EXT_CSD_BUS_WIDTH	183	/* R/W */
 #define EXT_CSD_HS_TIMING	185	/* R/W */
 #define EXT_CSD_CARD_TYPE	196	/* RO */
+#define EXT_CSD_REV		192	/* RO */
 #define EXT_CSD_SEC_CNT		212	/* RO, 4 bytes */
 
 /*