[PATCH 3/3] drm/fsl-dcu: enable pixel clock when enabling CRTC

[Stefan Agner]

The pixel clock should not be on if the CRTC is not in use, hence
move clock enable/disable calls into CRTC callbacks.

Signed-off-by: Stefan Agner <stefan at agner.ch>
---
 drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c |  7 +++++++
 drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c  | 16 +---------------
 2 files changed, 8 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c 
b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c
index 3371635..4fe0403 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c
@@ -51,13 +51,20 @@ static void fsl_dcu_drm_disable_crtc(struct drm_crtc *crtc)
                           DCU_MODE_DCU_MODE(DCU_MODE_OFF));
        regmap_write(fsl_dev->regmap, DCU_UPDATE_MODE,
                     DCU_UPDATE_MODE_READREG);
+       clk_disable_unprepare(fsl_dev->pix_clk);
 }

 static void fsl_dcu_drm_crtc_enable(struct drm_crtc *crtc)
 {
        struct drm_device *dev = crtc->dev;
        struct fsl_dcu_drm_device *fsl_dev = dev->dev_private;
+       int ret;

+       ret = clk_prepare_enable(fsl_dev->pix_clk);
+       if (ret < 0) {
+               dev_err(fsl_dev->dev, "failed to enable pix clk\n");
+               return;
+       }
        regmap_update_bits(fsl_dev->regmap, DCU_DCU_MODE,
                           DCU_MODE_DCU_MODE_MASK,
                           DCU_MODE_DCU_MODE(DCU_MODE_NORMAL));
diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c 
b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
index 0884c45..a6863f9 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
@@ -267,12 +267,6 @@ static int fsl_dcu_drm_pm_resume(struct device *dev)
                return ret;
        }

-       ret = clk_prepare_enable(fsl_dev->pix_clk);
-       if (ret < 0) {
-               dev_err(dev, "failed to enable pix clk\n");
-               goto disable_dcu_clk;
-       }
-
        fsl_dcu_drm_init_planes(fsl_dev->drm);
        drm_atomic_helper_resume(fsl_dev->drm, fsl_dev->state);

@@ -401,18 +395,12 @@ static int fsl_dcu_drm_probe(struct platform_device *pdev)
                goto disable_clk;
        }

-       ret = clk_prepare_enable(fsl_dev->pix_clk);
-       if (ret < 0) {
-               dev_err(dev, "failed to enable pix clk\n");
-               goto unregister_pix_clk;
-       }
-
        fsl_dev->tcon = fsl_tcon_init(dev);

        drm = drm_dev_alloc(driver, dev);
        if (IS_ERR(drm)) {
                ret = PTR_ERR(drm);
-               goto disable_pix_clk;
+               goto unregister_pix_clk;
        }

        fsl_dev->dev = dev;
@@ -433,8 +421,6 @@ static int fsl_dcu_drm_probe(struct platform_device *pdev)

 unref:
        drm_dev_unref(drm);
-disable_pix_clk:
-       clk_disable_unprepare(fsl_dev->pix_clk);
 unregister_pix_clk:
        clk_unregister(fsl_dev->pix_clk);
 disable_clk:
-- 
2.10.0