Use clk_prepare_enable/clk_unprepare_disable instead of preparing the clocks during the driver initalization and then using just clk_disable/ clk_enable. The clock framework doesn't guarantee a clock will not get enabled during e.g. clk_set_parent if clk_prepare has been called on it. So we ensure clk_prepare() is called only when it is safe to enable the clocks, i.e. the parent clocks and the clocks' frequencies are set. It must be ensured the FIMC-IS clocks have proper frequencies before they are enabled, otherwise the whole system will hang. Signed-off-by: Sylwester Nawrocki <s.nawrocki@xxxxxxxxxxx> Signed-off-by: Kyunmin Park <kyungmin.park@xxxxxxxxxxx> --- drivers/media/platform/exynos4-is/fimc-is.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-) diff --git a/drivers/media/platform/exynos4-is/fimc-is.c b/drivers/media/platform/exynos4-is/fimc-is.c index 140c58f..520e439 100644 --- a/drivers/media/platform/exynos4-is/fimc-is.c +++ b/drivers/media/platform/exynos4-is/fimc-is.c @@ -70,7 +70,6 @@ static void fimc_is_put_clocks(struct fimc_is *is) for (i = 0; i < ISS_CLKS_MAX; i++) { if (IS_ERR(is->clocks[i])) continue; - clk_unprepare(is->clocks[i]); clk_put(is->clocks[i]); is->clocks[i] = ERR_PTR(-EINVAL); } @@ -89,12 +88,6 @@ static int fimc_is_get_clocks(struct fimc_is *is) ret = PTR_ERR(is->clocks[i]); goto err; } - ret = clk_prepare(is->clocks[i]); - if (ret < 0) { - clk_put(is->clocks[i]); - is->clocks[i] = ERR_PTR(-EINVAL); - goto err; - } } return 0; @@ -102,7 +95,7 @@ err: fimc_is_put_clocks(is); dev_err(&is->pdev->dev, "failed to get clock: %s\n", fimc_is_clocks[i]); - return -ENXIO; + return ret; } static int fimc_is_setup_clocks(struct fimc_is *is) @@ -143,7 +136,7 @@ int fimc_is_enable_clocks(struct fimc_is *is) for (i = 0; i < ISS_GATE_CLKS_MAX; i++) { if (IS_ERR(is->clocks[i])) continue; - ret = clk_enable(is->clocks[i]); + ret = clk_prepare_enable(is->clocks[i]); if (ret < 0) { dev_err(&is->pdev->dev, "clock %s enable failed\n", fimc_is_clocks[i]); @@ -162,7 +155,7 @@ void fimc_is_disable_clocks(struct fimc_is *is) for (i = 0; i < ISS_GATE_CLKS_MAX; i++) { if (!IS_ERR(is->clocks[i])) { - clk_disable(is->clocks[i]); + clk_disable_unprepare(is->clocks[i]); pr_debug("disabled clock: %s\n", fimc_is_clocks[i]); } } -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html