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>

diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c
index 6f6fc52..dcb3dee 100644 (file)
--- a/drivers/mmc/core/sdio_cis.c
+++ b/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);