[PATCH 2/2] mmc: gen_atmel_mci: NULL check variable before use

[Andrew Goodbody]

In mci_send_cmd the pointer 'data' is optional so guard its use with a
NULL check to prevent any attempt to dereference it when not provided.

This issue was found by Smatch.

Signed-off-by: Andrew Goodbody <andrew.goodbody at linaro.org>
---
 drivers/mmc/gen_atmel_mci.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/mmc/gen_atmel_mci.c b/drivers/mmc/gen_atmel_mci.c
index 62aa6b3cb0b..838b4f4a65a 100644
--- a/drivers/mmc/gen_atmel_mci.c
+++ b/drivers/mmc/gen_atmel_mci.c
@@ -263,13 +263,15 @@ mci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data)
 	/* Figure out the transfer arguments */
 	cmdr = mci_encode_cmd(cmd, data, &error_flags);
 
-	mci_set_blklen(mci, data->blocksize);
+	if (data) {
+		mci_set_blklen(mci, data->blocksize);
 
-	/* For multi blocks read/write, set the block register */
-	if ((cmd->cmdidx == MMC_CMD_READ_MULTIPLE_BLOCK)
-			|| (cmd->cmdidx == MMC_CMD_WRITE_MULTIPLE_BLOCK))
-		writel(data->blocks | MMCI_BF(BLKLEN, data->blocksize),
-		       &mci->blkr);
+		/* For multi blocks read/write, set the block register */
+		if (cmd->cmdidx == MMC_CMD_READ_MULTIPLE_BLOCK ||
+		    cmd->cmdidx == MMC_CMD_WRITE_MULTIPLE_BLOCK)
+			writel(data->blocks | MMCI_BF(BLKLEN, data->blocksize),
+			       &mci->blkr);
+	}
 
 	/* Send the command */
 	writel(cmd->cmdarg, &mci->argr);

-- 
2.39.5