mmc: block: support no access to boot partitions

Intel Medfield platform blocks access to eMMC boot partitions which
results in switch errors.  Since there is no access, mmcboot0/1
devices should not be created.  Add a host capability to reflect that.

Change-Id: I67d7e1301bb13ce6b01fb44e511ea21cfbf7e4bd
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
[subhashj@codeaurora.org: Fixed merge conflicts]
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index db14e38..46f71a1 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -241,6 +241,7 @@
 
 	unsigned int		caps2;		/* More host capabilities */
 
+#define MMC_CAP2_BOOTPART_NOACC	(1 << 0)	/* Boot partition no access */
 #define MMC_CAP2_CACHE_CTRL	(1 << 1)	/* Allow cache control */
 #define MMC_CAP2_POWEROFF_NOTIFY (1 << 2)	/* Notify poweroff supported */
 #define MMC_CAP2_NO_MULTI_READ	(1 << 3)	/* Multiblock reads don't work */
@@ -475,6 +476,11 @@
 	return host->caps & MMC_CAP_CMD23;
 }
 
+static inline int mmc_boot_partition_access(struct mmc_host *host)
+{
+	return !(host->caps2 & MMC_CAP2_BOOTPART_NOACC);
+}
+
 #ifdef CONFIG_MMC_CLKGATE
 void mmc_host_clk_hold(struct mmc_host *host);
 void mmc_host_clk_release(struct mmc_host *host);