dfu: defer parsing of device string to IO backend

Devices are not all identified by a single integer. To support
this, defer the parsing of the device string to the IO backed, so that
it can apply the appropriate rules.

SPI devices are specified as controller:chip_select. SPI/SF support will
be added soon.

MMC devices can also be specified as controller[.hwpart][:partition] in
many commands, although we don't support that syntax in DFU.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
diff --git a/drivers/dfu/dfu_mmc.c b/drivers/dfu/dfu_mmc.c
index 322bd8c..72fa03e 100644
--- a/drivers/dfu/dfu_mmc.c
+++ b/drivers/dfu/dfu_mmc.c
@@ -27,7 +27,7 @@
 	if (part == mmc->part_num)
 		return 0;
 
-	ret = mmc_switch_part(dfu->dev_num, part);
+	ret = mmc_switch_part(dfu->data.mmc.dev_num, part);
 	if (ret) {
 		error("Cannot switch to partition %d\n", part);
 		return ret;
@@ -40,7 +40,7 @@
 static int mmc_block_op(enum dfu_op op, struct dfu_entity *dfu,
 			u64 offset, void *buf, long *len)
 {
-	struct mmc *mmc = find_mmc_device(dfu->dev_num);
+	struct mmc *mmc = find_mmc_device(dfu->data.mmc.dev_num);
 	u32 blk_start, blk_count, n = 0;
 	int ret, part_num_bkp = 0;
 
@@ -67,15 +67,15 @@
 	}
 
 	debug("%s: %s dev: %d start: %d cnt: %d buf: 0x%p\n", __func__,
-	      op == DFU_OP_READ ? "MMC READ" : "MMC WRITE", dfu->dev_num,
-	      blk_start, blk_count, buf);
+	      op == DFU_OP_READ ? "MMC READ" : "MMC WRITE",
+	      dfu->data.mmc.dev_num, blk_start, blk_count, buf);
 	switch (op) {
 	case DFU_OP_READ:
-		n = mmc->block_dev.block_read(dfu->dev_num, blk_start,
+		n = mmc->block_dev.block_read(dfu->data.mmc.dev_num, blk_start,
 					      blk_count, buf);
 		break;
 	case DFU_OP_WRITE:
-		n = mmc->block_dev.block_write(dfu->dev_num, blk_start,
+		n = mmc->block_dev.block_write(dfu->data.mmc.dev_num, blk_start,
 					       blk_count, buf);
 		break;
 	default:
@@ -270,7 +270,7 @@
  *	4th (optional):
  *		mmcpart <num> (access to HW eMMC partitions)
  */
-int dfu_fill_entity_mmc(struct dfu_entity *dfu, char *s)
+int dfu_fill_entity_mmc(struct dfu_entity *dfu, char *devstr, char *s)
 {
 	const char *entity_type;
 	size_t second_arg;
@@ -281,6 +281,8 @@
 	const char *argv[3];
 	const char **parg = argv;
 
+	dfu->data.mmc.dev_num = simple_strtoul(devstr, NULL, 10);
+
 	for (; parg < argv + sizeof(argv) / sizeof(*argv); ++parg) {
 		*parg = strsep(&s, " ");
 		if (*parg == NULL) {
@@ -297,9 +299,10 @@
 	second_arg = simple_strtoul(argv[1], NULL, 0);
 	third_arg = simple_strtoul(argv[2], NULL, 0);
 
-	mmc = find_mmc_device(dfu->dev_num);
+	mmc = find_mmc_device(dfu->data.mmc.dev_num);
 	if (mmc == NULL) {
-		error("Couldn't find MMC device no. %d.\n", dfu->dev_num);
+		error("Couldn't find MMC device no. %d.\n",
+		      dfu->data.mmc.dev_num);
 		return -ENODEV;
 	}