mmc: sdio: fall back to SDIO 1.0 for broken 1.1 cards

I have two SDIO WLAN cards which specify being SDIO Rev. 1.1 cards but
their FUNCE tuple reports the smaller size of a Rev 1.0 card. So,
enforce 1.0 on these cards to avoid reading the not present registers.
They are not really used anyhow. My cards initialize properly after this
patch.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/core/sdio_cis.c

@@ -177,8 +177,13 @@ static int cistpl_funce_func(struct mmc_card *card, struct sdio_func *func,
 	vsn = func->card->cccr.sdio_vsn;
 	min_size = (vsn == SDIO_SDIO_REV_1_00) ? 28 : 42;
 
-	if (size < min_size)
+	if (size == 28 && vsn == SDIO_SDIO_REV_1_10) {
+		pr_warn("%s: card has broken SDIO 1.1 CIS, forcing SDIO 1.0\n",
+			mmc_hostname(card->host));
+		vsn = SDIO_SDIO_REV_1_00;
+	} else if (size < min_size) {
 		return -EINVAL;
+	}
 
 	/* TPLFE_MAX_BLK_SIZE */
 	func->max_blksize = buf[12] | (buf[13] << 8);