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| author | Sylwester Nawrocki <s.nawrocki@samsung.com> | 2013-05-31 13:40:36 +0200 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2013-06-09 00:53:16 +0200 |
| commit | b4155d7d5b2c4e82238d629c451f7c27c9f37d9c (patch) | |
| tree | 8ac568ea27b7786ddd68bf408fb2ed6e7b1d6aa2 /drivers | |
| parent | [media] exynos4-is: Prevent NULL pointer dereference when firmware isn't loaded (diff) | |
| download | linux-b4155d7d5b2c4e82238d629c451f7c27c9f37d9c.tar.xz linux-b4155d7d5b2c4e82238d629c451f7c27c9f37d9c.zip | |
[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 <s.nawrocki@samsung.com>
Signed-off-by: Kyunmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/media/platform/exynos4-is/fimc-is.c | 13 |
1 files 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]); } } |