Re: [PATCH v4] drm/exynos: prepare FIMD clocks

On 8 April 2013 16:37, Vikas Sajjan vikas.sajjan@linaro.org wrote:

While migrating to common clock framework (CCF), I found that the FIMD clocks were pulled down by the CCF. If CCF finds any clock(s) which has NOT been claimed by any of the drivers, then such clock(s) are PULLed low by CCF.

Calling clk_prepare() for FIMD clocks fixes the issue.

This patch also replaces clk_disable() with clk_unprepare() during exit, since clk_prepare() is called in fimd_probe().

I asked you about fixing your commit log too.. It still looks incorrect to me.

This patch doesn't have anything to do with CCF pulling clocks down, but calling clk_prepare() before clk_enable() is must now.. that's it.. nothing more.

Signed-off-by: Vikas Sajjan vikas.sajjan@linaro.org

Changes since v3: - added clk_prepare() in fimd_probe() and clk_unprepare() in fimd_remove() as suggested by Viresh Kumar viresh.kumar@linaro.org Changes since v2: - moved clk_prepare_enable() and clk_disable_unprepare() from fimd_probe() to fimd_clock() as suggested by Inki Dae inki.dae@samsung.com Changes since v1: - added error checking for clk_prepare_enable() and also replaced clk_disable() with clk_disable_unprepare() during exit.

---

drivers/gpu/drm/exynos/exynos_drm_fimd.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_fimd.c b/drivers/gpu/drm/exynos/exynos_drm_fimd.c index 9537761..aa22370 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_fimd.c +++ b/drivers/gpu/drm/exynos/exynos_drm_fimd.c @@ -934,6 +934,16 @@ static int fimd_probe(struct platform_device *pdev) return ret; }

•   ret = clk_prepare(ctx->bus_clk);
  

•   if (ret < 0)
  

•           return ret;
  

•   ret = clk_prepare(ctx->lcd_clk);
  

•   if  (ret < 0) {
  

•           clk_unprepare(ctx->bus_clk);
  

•           return ret;
  

•   }
  

•   ctx->vidcon0 = pdata->vidcon0;
    ctx->vidcon1 = pdata->vidcon1;
    ctx->default_win = pdata->default_win;
  

@@ -981,8 +991,8 @@ static int fimd_remove(struct platform_device *pdev) if (ctx->suspended) goto out;

•   clk_disable(ctx->lcd_clk);
  

•   clk_disable(ctx->bus_clk);
  

•   clk_unprepare(ctx->lcd_clk);
  

•   clk_unprepare(ctx->bus_clk);
  

This looks wrong again.. You still need to call clk_disable() to make clk enabled count zero...