diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c
index a7406e3701c9..28e14c7a2540 100644
--- a/drivers/mmc/host/tmio_mmc_pio.c
+++ b/drivers/mmc/host/tmio_mmc_pio.c
@@ -209,6 +209,7 @@ static void tmio_mmc_set_clock(struct tmio_mmc_host *host, int new_clock)
 static void tmio_mmc_clk_stop(struct tmio_mmc_host *host)
 {
 	struct tmio_mmc_data *pdata = host->pdata;
+	struct resource *res = platform_get_resource(host->pdev, IORESOURCE_MEM, 0);
 
 	/*
 	 * Testing on sh-mobile showed that SDIO IRQs are unmasked when
@@ -218,8 +219,11 @@ static void tmio_mmc_clk_stop(struct tmio_mmc_host *host)
 	 */
 	if (pdata->flags & TMIO_MMC_SDIO_IRQ)
 		disable_irq(host->irq);
-	sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0000);
-	msleep(10);
+	/* implicit BUG_ON(!res) */
+	if (resource_size(res) > 0x100) {
+		sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0000);
+		msleep(10);
+	}
 	if (pdata->flags & TMIO_MMC_SDIO_IRQ) {
 		tmio_mmc_enable_sdio_irq(host->mmc, host->sdio_irq_enabled);
 		enable_irq(host->irq);
@@ -232,6 +236,7 @@ static void tmio_mmc_clk_stop(struct tmio_mmc_host *host)
 static void tmio_mmc_clk_start(struct tmio_mmc_host *host)
 {
 	struct tmio_mmc_data *pdata = host->pdata;
+	struct resource *res = platform_get_resource(host->pdev, IORESOURCE_MEM, 0);
 
 	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, 0x0100 |
 		sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
@@ -239,8 +244,11 @@ static void tmio_mmc_clk_start(struct tmio_mmc_host *host)
 	/* see comment in tmio_mmc_clk_stop above */
 	if (pdata->flags & TMIO_MMC_SDIO_IRQ)
 		disable_irq(host->irq);
-	sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0100);
-	msleep(10);
+	/* implicit BUG_ON(!res) */
+	if (resource_size(res) > 0x100) {
+		sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0100);
+		msleep(10);
+	}
 	if (pdata->flags & TMIO_MMC_SDIO_IRQ) {
 		tmio_mmc_enable_sdio_irq(host->mmc, host->sdio_irq_enabled);
 		enable_irq(host->irq);
@@ -249,12 +257,17 @@ static void tmio_mmc_clk_start(struct tmio_mmc_host *host)
 
 static void tmio_mmc_reset(struct tmio_mmc_host *host)
 {
+	struct resource *res = platform_get_resource(host->pdev, IORESOURCE_MEM, 0);
+
 	/* FIXME - should we set stop clock reg here */
 	sd_ctrl_write16(host, CTL_RESET_SD, 0x0000);
-	sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0000);
+	/* implicit BUG_ON(!res) */
+	if (resource_size(res) > 0x100)
+		sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0000);
 	msleep(10);
 	sd_ctrl_write16(host, CTL_RESET_SD, 0x0001);
-	sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0001);
+	if (resource_size(res) > 0x100)
+		sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0001);
 	msleep(10);
 }