[U-Boot] [PATCH v3] common: env_nand: Ensure that we have nand_info[0] prior to use

[Tom Rini]

Now that nand_info[] is an array of pointers we need to ensure that it's
been populated prior to use.  We may for example have ENV in NAND set in
configurations that run on boards with and without NAND (where default
env is fine enough, such as omap3_beagle and beagleboard (NAND) vs
beagle xM (no NAND)).

Fixes: b616d9b0a708 ("nand: Embed mtd_info in struct nand_chip")
Cc: Scott Wood <oss at buserror.net>
Signed-off-by: Tom Rini <trini at konsulko.com>
---
Changes in v3:
- Don't overload the blocksize check in readenv(), and now that
  blocksize would never be zero (this was the previous way to see that
  we had no NAND detected), remove that check.
- Address the CONFIG_ENV_OFFSET_OOB case in env_relocate_spec() as this
  too would fail now if no NAND was detected.

Changes in v2:
- Oops, move check on the saveenv side in to erase_and_write_env
---
 common/env_nand.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/common/env_nand.c b/common/env_nand.c
index fc99a5e3fc0d..2e28171ae094 100644
--- a/common/env_nand.c
+++ b/common/env_nand.c
@@ -163,6 +163,9 @@ static int erase_and_write_env(const struct env_location *location,
 {
 	int ret = 0;
 
+	if (!nand_info[0])
+		return 1;
+
 	printf("Erasing %s...\n", location->name);
 	if (nand_erase_opts(nand_info[0], &location->erase_opts))
 		return 1;
@@ -247,10 +250,10 @@ static int readenv(size_t offset, u_char *buf)
 	size_t blocksize, len;
 	u_char *char_ptr;
 
-	blocksize = nand_info[0]->erasesize;
-	if (!blocksize)
+	if (!nand_info[0])
 		return 1;
 
+	blocksize = nand_info[0]->erasesize;
 	len = min(blocksize, (size_t)CONFIG_ENV_SIZE);
 
 	while (amount_loaded < CONFIG_ENV_SIZE && offset < end) {
@@ -387,12 +390,12 @@ void env_relocate_spec(void)
 	ALLOC_CACHE_ALIGN_BUFFER(char, buf, CONFIG_ENV_SIZE);
 
 #if defined(CONFIG_ENV_OFFSET_OOB)
-	ret = get_nand_env_oob(nand_info[0], &nand_env_oob_offset);
 	/*
 	 * If unable to read environment offset from NAND OOB then fall through
 	 * to the normal environment reading code below
 	 */
-	if (!ret) {
+	if (nand_info[0] && !get_nand_env_oob(nand_info[0],
+					      &nand_env_oob_offset)) {
 		printf("Found Environment offset in OOB..\n");
 	} else {
 		set_default_env("!no env offset in OOB");
-- 
1.9.1