mmc: sd: fix the maximum au_size for SD3.0

Since SD Physical Layer specification V3.0, AU_SIZE is supported up
to 0xf.  So If SD-card is supported v3.0, then max_au should be 0xf.
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

drivers/mmc/core/sd.c

@@ -215,7 +215,7 @@ static int mmc_decode_scr(struct mmc_card *card)
 static int mmc_read_ssr(struct mmc_card *card)
 {
 	unsigned int au, es, et, eo;
-	int err, i;
+	int err, i, max_au;
 	u32 *ssr;
 
 	if (!(card->csd.cmdclass & CCC_APP_SPEC)) {
@@ -239,12 +239,15 @@ static int mmc_read_ssr(struct mmc_card *card)
 	for (i = 0; i < 16; i++)
 		ssr[i] = be32_to_cpu(ssr[i]);
 
+	/* SD3.0 increases max AU size to 64MB (0xF) from 4MB (0x9) */
+	max_au = card->scr.sda_spec3 ? 0xF : 0x9;
+
 	/*
 	 * UNSTUFF_BITS only works with four u32s so we have to offset the
 	 * bitfield positions accordingly.
 	 */
 	au = UNSTUFF_BITS(ssr, 428 - 384, 4);
-	if (au > 0 && au <= 9) {
+	if (au > 0 && au <= max_au) {
 		card->ssr.au = 1 << (au + 4);
 		es = UNSTUFF_BITS(ssr, 408 - 384, 16);
 		et = UNSTUFF_BITS(ssr, 402 - 384, 6);