commonlib/storage: Make sd_mmc_go_idle an api

change sd_mmc_go_idle to be accessible from other files
so that we have an api to send CMD0 and reset the card.

TEST=Boot to OS

Change-Id: I064a9bded347be5d500047df92d1c448c3392016
Signed-off-by: Bora Guvendik <>
Reviewed-by: Justin TerAvest <>
Tested-by: build bot (Jenkins) <>
diff --git a/src/commonlib/storage/sd_mmc.c b/src/commonlib/storage/sd_mmc.c
index 0ca53b7..0c89085 100644
--- a/src/commonlib/storage/sd_mmc.c
+++ b/src/commonlib/storage/sd_mmc.c
@@ -81,7 +81,7 @@
 	return freq * mult;
-static int sd_mmc_go_idle(struct storage_media *media)
+int sd_mmc_go_idle(struct storage_media *media)
 	struct sd_mmc_ctrlr *ctrlr = media->ctrlr;
diff --git a/src/commonlib/storage/sd_mmc.h b/src/commonlib/storage/sd_mmc.h
index b9aea46..e37f8f4 100644
--- a/src/commonlib/storage/sd_mmc.h
+++ b/src/commonlib/storage/sd_mmc.h
@@ -46,6 +46,7 @@
 int sd_mmc_enter_standby(struct storage_media *media);
 uint64_t sd_mmc_extract_uint32_bits(const uint32_t *array, int start,
 	int count);
+int sd_mmc_go_idle(struct storage_media *media);
 int sd_mmc_send_status(struct storage_media *media, ssize_t tries);
 int sd_mmc_set_blocklen(struct sd_mmc_ctrlr *ctrlr, int len);