hwrng: exynos - Use devm_clk_get_enabled() to get the clock

Use devm_clk_get_enabled() helper instead of calling devm_clk_get() and
then clk_prepare_enable(). It simplifies the error handling and makes
the code more compact. Also use dev_err_probe() to handle possible
-EPROBE_DEFER errors if the clock is not available yet.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Anand Moon <linux.amoon@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/char/hw_random/exynos-trng.c b/drivers/char/hw_random/exynos-trng.c
index 266bdad84f3cab8a196d012e546493b541d8c74c..997bd22f4498e3e1a66a19075bc0d8b3b22ac496 100644 (file)
--- a/drivers/char/hw_random/exynos-trng.c
+++ b/drivers/char/hw_random/exynos-trng.c
@@ -134,32 +134,23 @@ static int exynos_trng_probe(struct platform_device *pdev)
                goto err_pm_get;
        }
 
-       trng->clk = devm_clk_get(&pdev->dev, "secss");
+       trng->clk = devm_clk_get_enabled(&pdev->dev, "secss");
        if (IS_ERR(trng->clk)) {
-               ret = PTR_ERR(trng->clk);
-               dev_err(&pdev->dev, "Could not get clock.\n");
-               goto err_clock;
-       }
-
-       ret = clk_prepare_enable(trng->clk);
-       if (ret) {
-               dev_err(&pdev->dev, "Could not enable the clk.\n");
+               ret = dev_err_probe(&pdev->dev, PTR_ERR(trng->clk),
+                                   "Could not get clock\n");
                goto err_clock;
        }
 
        ret = devm_hwrng_register(&pdev->dev, &trng->rng);
        if (ret) {
                dev_err(&pdev->dev, "Could not register hwrng device.\n");
-               goto err_register;
+               goto err_clock;
        }
 
        dev_info(&pdev->dev, "Exynos True Random Number Generator.\n");
 
        return 0;
 
-err_register:
-       clk_disable_unprepare(trng->clk);
-
 err_clock:
        pm_runtime_put_noidle(&pdev->dev);
 
@@ -171,10 +162,6 @@ err_pm_get:
 
 static void exynos_trng_remove(struct platform_device *pdev)
 {
-       struct exynos_trng_dev *trng = platform_get_drvdata(pdev);
-
-       clk_disable_unprepare(trng->clk);
-
        pm_runtime_put_sync(&pdev->dev);
        pm_runtime_disable(&pdev->dev);
 }