[PATCH v4 2/3] driver: rng: Fix SMCCC TRNG crash

[Weizhao Ouyang]

Fix a SMCCC TRNG null pointer crash due to a failed smccc feature
binding.

Fixes: 53355bb86c25 ("drivers: rng: add smccc trng driver")
Reviewed-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
Signed-off-by: Weizhao Ouyang <o451686892 at gmail.com>
---
v3: add Fixes tag
---
 drivers/rng/smccc_trng.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/rng/smccc_trng.c b/drivers/rng/smccc_trng.c
index 3a4bb33941..3087cb991a 100644
--- a/drivers/rng/smccc_trng.c
+++ b/drivers/rng/smccc_trng.c
@@ -166,7 +166,7 @@ static int smccc_trng_probe(struct udevice *dev)
 	struct smccc_trng_priv *priv = dev_get_priv(dev);
 	struct arm_smccc_res res;
 
-	if (!(smccc_trng_is_supported(smccc->invoke_fn)))
+	if (!smccc || !(smccc_trng_is_supported(smccc->invoke_fn)))
 		return -ENODEV;
 
 	/* At least one of 64bit and 32bit interfaces is available */
-- 
2.40.1