From b4155d7d5b2c4e82238d629c451f7c27c9f37d9c Mon Sep 17 00:00:00 2001 From: Sylwester Nawrocki Date: Fri, 31 May 2013 08:40:36 -0300 Subject: [PATCH] [media] exynos4-is: Ensure fimc-is clocks are not enabled until properly configured 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 Signed-off-by: Kyunmin Park Signed-off-by: Mauro Carvalho Chehab --- 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 1adf6dfcb39e..89f28fe42709 100644 --- a/drivers/media/platform/exynos4-is/fimc-is.c +++ b/drivers/media/platform/exynos4-is/fimc-is.c @@ -71,7 +71,6 @@ 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); } @@ -90,12 +89,6 @@ 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; @@ -103,7 +96,7 @@ 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) @@ -144,7 +137,7 @@ 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]); @@ -163,7 +156,7 @@ 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]); } } -- 2.20.1