[PATCH v6 4/7] crypto: caam - check if RNG job failed

[Andrey Smirnov <andrew.smirnov@gmail.com>]

We shouldn't stay silent if RNG job fails. Add appropriate code to
check for that case and propagate error code up appropriately.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Horia Geantă <horia.geanta@nxp.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Iuliana Prodan <iuliana.prodan@nxp.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-imx@nxp.com
---
 drivers/crypto/caam/caamrng.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/crypto/caam/caamrng.c b/drivers/crypto/caam/caamrng.c
index 3960f5c81c97..554aafbd4d11 100644
--- a/drivers/crypto/caam/caamrng.c
+++ b/drivers/crypto/caam/caamrng.c
@@ -52,6 +52,11 @@ struct caam_rng_ctx {
 	struct kfifo fifo;
 };
 
+struct caam_rng_job_ctx {
+	struct completion *done;
+	int *err;
+};
+
 static struct caam_rng_ctx *to_caam_rng_ctx(struct hwrng *r)
 {
 	return container_of(r, struct caam_rng_ctx, rng);
@@ -60,12 +65,12 @@ static struct caam_rng_ctx *to_caam_rng_ctx(struct hwrng *r)
 static void caam_rng_done(struct device *jrdev, u32 *desc, u32 err,
 			  void *context)
 {
-	struct completion *done = context;
+	struct caam_rng_job_ctx *jctx = context;
 
 	if (err)
-		caam_jr_strstatus(jrdev, err);
+		*jctx->err = caam_jr_strstatus(jrdev, err);
 
-	complete(done);
+	complete(jctx->done);
 }
 
 static u32 *caam_init_desc(u32 *desc, dma_addr_t dst_dma, int len)
@@ -89,6 +94,10 @@ static int caam_rng_read_one(struct device *jrdev,
 {
 	dma_addr_t dst_dma;
 	int err;
+	struct caam_rng_job_ctx jctx = {
+		.done = done,
+		.err  = &err,
+	};
 
 	len = min_t(int, len, CAAM_RNG_MAX_FIFO_STORE_SIZE);
 
@@ -101,7 +110,7 @@ static int caam_rng_read_one(struct device *jrdev,
 	init_completion(done);
 	err = caam_jr_enqueue(jrdev,
 			      caam_init_desc(desc, dst_dma, len),
-			      caam_rng_done, done);
+			      caam_rng_done, &jctx);
 	if (!err)
 		wait_for_completion(done);
 
-- 
2.21.0