mmc: core: document mmc_hw_reset()

Add documentation for mmc_hw_reset to make sure the intended use case is
clear.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20200918215446.65654-1-wsa+renesas@sang-engineering.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 8ccae6452b9c..d42037f0f10d 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -2063,6 +2063,16 @@ static void mmc_hw_reset_for_init(struct mmc_host *host)
 	host->ops->hw_reset(host);
 }
 
+/**
+ * mmc_hw_reset - reset the card in hardware
+ * @host: MMC host to which the card is attached
+ *
+ * Hard reset the card. This function is only for upper layers, like the
+ * block layer or card drivers. You cannot use it in host drivers (struct
+ * mmc_card might be gone then).
+ *
+ * Return: 0 on success, -errno on failure
+ */
 int mmc_hw_reset(struct mmc_host *host)
 {
 	int ret;