From d47292691977fd77f02af44359594e46411f4a63 Mon Sep 17 00:00:00 2001
From: Kever Yang <kever.yang@rock-chips.com>
Date: Sat, 10 Feb 2018 17:55:37 +0800
Subject: [PATCH] disk: part: scan the disk if the part_type is unknown

If a DUT do not have partition table, and we write one with 'gpt write'
cmd, we should able to list the partition with 'part list' cmd.
It's reasonable to scan the disk again if the initial part_type is
unknown in case we just write a new one into disk.

Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
---
 disk/part.c | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/disk/part.c b/disk/part.c
index e9e18a0..16de7a2 100644
--- a/disk/part.c
+++ b/disk/part.c
@@ -27,16 +27,28 @@
 DECLARE_GLOBAL_DATA_PTR;
 
 #ifdef CONFIG_HAVE_BLOCK_DEVICE
-static struct part_driver *part_driver_lookup_type(int part_type)
+static struct part_driver *part_driver_lookup_type(struct blk_desc *dev_desc)
 {
 	struct part_driver *drv =
 		ll_entry_start(struct part_driver, part_driver);
 	const int n_ents = ll_entry_count(struct part_driver, part_driver);
 	struct part_driver *entry;
 
-	for (entry = drv; entry != drv + n_ents; entry++) {
-		if (part_type == entry->part_type)
-			return entry;
+	if (dev_desc->part_type == PART_TYPE_UNKNOWN) {
+		for (entry = drv; entry != drv + n_ents; entry++) {
+			int ret;
+
+			ret = entry->test(dev_desc);
+			if (!ret) {
+				dev_desc->part_type = entry->part_type;
+				return entry;
+			}
+		}
+	} else {
+		for (entry = drv; entry != drv + n_ents; entry++) {
+			if (dev_desc->part_type == entry->part_type)
+				return entry;
+		}
 	}
 
 	/* Not found */
@@ -285,7 +297,7 @@ void part_print(struct blk_desc *dev_desc)
 {
 	struct part_driver *drv;
 
-	drv = part_driver_lookup_type(dev_desc->part_type);
+	drv = part_driver_lookup_type(dev_desc);
 	if (!drv) {
 		printf("## Unknown partition table type %x\n",
 		       dev_desc->part_type);
@@ -314,7 +326,7 @@ int part_get_info(struct blk_desc *dev_desc, int part,
 	info->type_guid[0] = 0;
 #endif
 
-	drv = part_driver_lookup_type(dev_desc->part_type);
+	drv = part_driver_lookup_type(dev_desc);
 	if (!drv) {
 		debug("## Unknown partition table type %x\n",
 		      dev_desc->part_type);