[MMC] sdhci: Test for invalid block size

The controller has an upper limit on the block size. Make sure we do not
cross it.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/mmc/sdhci.h b/drivers/mmc/sdhci.h
index 8ed2a89..b1aa3ac 100644
--- a/drivers/mmc/sdhci.h
+++ b/drivers/mmc/sdhci.h
@@ -131,6 +131,8 @@
 #define  SDHCI_TIMEOUT_CLK_UNIT	0x00000080
 #define  SDHCI_CLOCK_BASE_MASK	0x00003F00
 #define  SDHCI_CLOCK_BASE_SHIFT	8
+#define  SDHCI_MAX_BLOCK_MASK	0x00030000
+#define  SDHCI_MAX_BLOCK_SHIFT  16
 #define  SDHCI_CAN_DO_DMA	0x00400000
 #define  SDHCI_CAN_VDD_330	0x01000000
 #define  SDHCI_CAN_VDD_300	0x02000000
@@ -161,6 +163,7 @@
 
 	unsigned int		max_clk;	/* Max possible freq (MHz) */
 	unsigned int		timeout_clk;	/* Timeout freq (KHz) */
+	unsigned int		max_block;	/* Max block size (bytes) */
 
 	unsigned int		clock;		/* Current clock (MHz) */
 	unsigned short		power;		/* Current voltage */