[PATCH 4.16 238/272] hwrng: bcm2835 - Handle deferred clock properly

Greg Kroah-Hartman
2018-05-28T11:16:36Z

From: Stefan Wahren <stefan.wahren@i2se.com>

[ Upstream commit 7b4c5d30d0bd2b22c09d4d993a76e0973a873891 ]

In case the probe of the clock is deferred, we would assume it is
optional. This is wrong, so defer the probe of this driver until
the clock is available.

Fixes: 791af4f4907a ("hwrng: bcm2835 - Manage an optional clock")
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/char/hw_random/bcm2835-rng.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/char/hw_random/bcm2835-rng.c
+++ b/drivers/char/hw_random/bcm2835-rng.c
@@ -163,6 +163,8 @@ static int bcm2835_rng_probe(struct plat

/* Clock is optional on most platforms */
priv->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(priv->clk) && PTR_ERR(priv->clk) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;

priv->rng.name = pdev->name;
priv->rng.init = bcm2835_rng_init;