3 files changed, 25 insertions, 0 deletions

diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index 2dd4cfe7ca17..b9dee28ee7d0 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -296,6 +296,12 @@ static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr,
         card->type = MMC_TYPE_SDIO;
 
         /*
+         * Call the optional HC's init_card function to handle quirks.
+         */
+        if (host->ops->init_card)
+                host->ops->init_card(host, card);
+
+        /*
          * For native busses:  set card RCA and quit open drain mode.
          */
         if (!powered_resume && !mmc_host_is_spi(host)) {
diff --git a/drivers/mmc/host/mxcmmc.c b/drivers/mmc/host/mxcmmc.c
index 51e880c8f193..2c53024ee439 100644
--- a/drivers/mmc/host/mxcmmc.c
+++ b/drivers/mmc/host/mxcmmc.c
@@ -724,11 +724,27 @@ static void mxcmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
         spin_unlock_irqrestore(&host->lock, flags);
 }
 
+static void mxcmci_init_card(struct mmc_host *host, struct mmc_card *card)
+{
+        /*
+         * MX3 SoCs have a silicon bug which corrupts CRC calculation of
+         * multi-block transfers when connected SDIO peripheral doesn't
+         * drive the BUSY line as required by the specs.
+         * One way to prevent this is to only allow 1-bit transfers.
+         */
+
+        if (cpu_is_mx3() && card->type == MMC_TYPE_SDIO)
+                host->caps &= ~MMC_CAP_4_BIT_DATA;
+        else
+                host->caps |= MMC_CAP_4_BIT_DATA;
+}
+
 static const struct mmc_host_ops mxcmci_ops = {
         .request                = mxcmci_request,
         .set_ios                = mxcmci_set_ios,
         .get_ro                 = mxcmci_get_ro,
         .enable_sdio_irq        = mxcmci_enable_sdio_irq,
+        .init_card              = mxcmci_init_card,
 };
 
 static int mxcmci_probe(struct platform_device *pdev)
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 43eaf5ca5848..3196c84cc630 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -108,6 +108,9 @@ struct mmc_host_ops {
         int     (*get_cd)(struct mmc_host *host);
 
         void    (*enable_sdio_irq)(struct mmc_host *host, int enable);
+
+        /* optional callback for HC quirks */
+        void    (*init_card)(struct mmc_host *host, struct mmc_card *card);
 };
 
 struct mmc_card;