hwrng: ks-sa - fix division by zero in ks_sa_rng_init

Fix division by zero in ks_sa_rng_init caused by missing clock
pointer initialization. The clk_get_rate() call is performed on
an uninitialized clk pointer, resulting in division by zero when
calculating delay values.

Add clock initialization code before using the clock.

Fixes: 6d01d85 ("hwrng: ks-sa - Add minimum sleep time before ready-polling")
Signed-off-by: Nishanth Menon <nm@ti.com>

 drivers/char/hw_random/ks-sa-rng.c | 7 +++++++
 1 file changed, 7 insertions(+)
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Author: nmenon

drivers/char/hw_random/ks-sa-rng.c

@@ -231,6 +231,10 @@ static int ks_sa_rng_probe(struct platform_device *pdev)
 	if (IS_ERR(ks_sa_rng->regmap_cfg))
 		return dev_err_probe(dev, -EINVAL, "syscon_node_to_regmap failed\n");
 
+	ks_sa_rng->clk = devm_clk_get_enabled(dev, NULL);
+	if (IS_ERR(ks_sa_rng->clk))
+		return dev_err_probe(dev, PTR_ERR(ks_sa_rng->clk), "Failed to get clock\n");
+
 	pm_runtime_enable(dev);
 	ret = pm_runtime_resume_and_get(dev);
 	if (ret < 0) {