[U-Boot] [PATCH] mmc: show error message when "mmc dev" command fails

[Masahiro Yamada]

Currently, "mmc dev" can silently fail.  In case of failure, tell
the user about it.

Signed-off-by: Masahiro Yamada <yamada.masahiro at socionext.com>
---

 cmd/mmc.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/cmd/mmc.c b/cmd/mmc.c
index 1c7156f..87a9fb6 100644
--- a/cmd/mmc.c
+++ b/cmd/mmc.c
@@ -463,8 +463,10 @@ static int do_mmc_dev(cmd_tbl_t *cmdtp, int flag,
 	}
 
 	mmc = init_mmc_device(dev, true);
-	if (!mmc)
+	if (!mmc) {
+		printf("could not switch to mmc%d\n", dev);
 		return CMD_RET_FAILURE;
+	}
 
 	ret = mmc_select_hwpart(dev, part);
 	printf("switch to partitions #%d, %s\n",
-- 
1.9.1