mmc: provide a select_hwpart implementation for get_device()

This enables specifying which eMMC HW partition to target for any U-Boot
command that uses the generic get_partition() function to parse its
command-line arguments.

Acked-by: Pantelis Antoniou <panto@antoniou-consulting.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>

disk/part.c

@@ -39,7 +39,11 @@ static const struct block_drvr block_drvr[] = {
 	{ .name = "usb", .get_dev = usb_stor_get_dev, },
 #endif
 #if defined(CONFIG_MMC)
-	{ .name = "mmc", .get_dev = mmc_get_dev, },
+	{
+		.name = "mmc",
+		.get_dev = mmc_get_dev,
+		.select_hwpart = mmc_select_hwpart,
+	},
 #endif
 #if defined(CONFIG_SYSTEMACE)
 	{ .name = "ace", .get_dev = systemace_get_dev, },

drivers/mmc/mmc.c

@@ -552,6 +552,32 @@ static int mmc_set_capacity(struct mmc *mmc, int part_num)
 	return 0;
 }
 
+int mmc_select_hwpart(int dev_num, int hwpart)
+{
+	struct mmc *mmc = find_mmc_device(dev_num);
+	int ret;
+
+	if (!mmc)
+		return -1;
+
+	if (mmc->part_num == hwpart)
+		return 0;
+
+	if (mmc->part_config == MMCPART_NOAVAILABLE) {
+		printf("Card doesn't support part_switch\n");
+		return -1;
+	}
+
+	ret = mmc_switch_part(dev_num, hwpart);
+	if (ret)
+		return -1;
+
+	mmc->part_num = hwpart;
+
+	return 0;
+}
+
+
 int mmc_switch_part(int dev_num, unsigned int part_num)
 {
 	struct mmc *mmc = find_mmc_device(dev_num);

include/part.h

@@ -103,6 +103,7 @@ block_dev_desc_t* sata_get_dev(int dev);
 block_dev_desc_t* scsi_get_dev(int dev);
 block_dev_desc_t* usb_stor_get_dev(int dev);
 block_dev_desc_t* mmc_get_dev(int dev);
+int mmc_select_hwpart(int dev_num, int hwpart);
 block_dev_desc_t* systemace_get_dev(int dev);
 block_dev_desc_t* mg_disk_get_dev(int dev);
 block_dev_desc_t *host_get_dev(int dev);
@@ -126,6 +127,7 @@ static inline block_dev_desc_t* sata_get_dev(int dev) { return NULL; }
 static inline block_dev_desc_t* scsi_get_dev(int dev) { return NULL; }
 static inline block_dev_desc_t* usb_stor_get_dev(int dev) { return NULL; }
 static inline block_dev_desc_t* mmc_get_dev(int dev) { return NULL; }
+static inline int mmc_select_hwpart(int dev_num, int hwpart) { return -1; }
 static inline block_dev_desc_t* systemace_get_dev(int dev) { return NULL; }
 static inline block_dev_desc_t* mg_disk_get_dev(int dev) { return NULL; }
 static inline block_dev_desc_t *host_get_dev(int dev) { return NULL; }