[U-Boot] [PATCH] cmd_mmc.c: check mmc_init() during mmc dev

mmc dev ${devnum} will return 0 as success even if there is no card inserted. Booting script like tegra-common-post.h will call mmc dev ${devnum} to check the mmc device status, it always return 0 even if mmc_init() fails.
Check mmc_init() return value let mmc dev command return failure when mmc_init() fails.
Signed-off-by: Bryan Wu pengw@nvidia.com --- common/cmd_mmc.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/common/cmd_mmc.c b/common/cmd_mmc.c index c1916c9..56dcf48 100644 --- a/common/cmd_mmc.c +++ b/common/cmd_mmc.c @@ -195,6 +195,7 @@ static int do_mmcops(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) } else if (strcmp(argv[1], "dev") == 0) { int dev, part = -1; struct mmc *mmc; + int ret;
if (argc == 2) dev = curr_device; @@ -217,7 +218,10 @@ static int do_mmcops(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) return 1; }
- mmc_init(mmc); + ret = mmc_init(mmc); + if (ret) + return ret; + if (part != -1) { int ret; if (mmc->part_config == MMCPART_NOAVAILABLE) {

On 05/19/2014 06:17 PM, Bryan Wu wrote:
mmc dev ${devnum} will return 0 as success even if there is no card inserted. Booting script like tegra-common-post.h will call mmc dev ${devnum} to check the mmc device status, it always return 0 even if mmc_init() fails.
Check mmc_init() return value let mmc dev command return failure when mmc_init() fails.
You probably want to Cc the MMC maintainer.
diff --git a/common/cmd_mmc.c b/common/cmd_mmc.c
@@ -195,6 +195,7 @@ static int do_mmcops(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) } else if (strcmp(argv[1], "dev") == 0) { int dev, part = -1; struct mmc *mmc;
int ret;
The latest u-boot.git master branch already declares ret a couple lines above. Hence, this patch doesn't compile.
mmc_init(mmc);
ret = mmc_init(mmc);
if (ret)
return ret;
I know that I said off-list to return ret here, but it actually looks like U-Boot commands must not return arbitrary values, but rather must return 0, 1, or CMD_RET_USAGE. The current code prints the following on failure:
Tegra124 (Jetson TK1) # mmc dev 1 MMC: no card present exit not allowed from main input shell.
I'll send a V2 patch with these fixed.

On Tue, May 20, 2014 at 9:55 AM, Stephen Warren swarren@wwwdotorg.org wrote:
On 05/19/2014 06:17 PM, Bryan Wu wrote:
mmc dev ${devnum} will return 0 as success even if there is no card inserted. Booting script like tegra-common-post.h will call mmc dev ${devnum} to check the mmc device status, it always return 0 even if mmc_init() fails.
Check mmc_init() return value let mmc dev command return failure when mmc_init() fails.
You probably want to Cc the MMC maintainer.
diff --git a/common/cmd_mmc.c b/common/cmd_mmc.c
@@ -195,6 +195,7 @@ static int do_mmcops(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) } else if (strcmp(argv[1], "dev") == 0) { int dev, part = -1; struct mmc *mmc;
int ret;
The latest u-boot.git master branch already declares ret a couple lines above. Hence, this patch doesn't compile.
mmc_init(mmc);
ret = mmc_init(mmc);
if (ret)
return ret;
I know that I said off-list to return ret here, but it actually looks like U-Boot commands must not return arbitrary values, but rather must return 0, 1, or CMD_RET_USAGE. The current code prints the following on failure:
Tegra124 (Jetson TK1) # mmc dev 1 MMC: no card present exit not allowed from main input shell.
I'll send a V2 patch with these fixed.
Thanks for pushing this. I will update downstream version.
-Bryan
participants (2)
-
Bryan Wu
-
Stephen Warren