drm/msm/mdp4: register the LVDS PLL as a clock provider

The LVDS/LCDC controller uses pixel clock coming from the multimedia
controller (mmcc) rather than using the PLL directly. Stop using LVDS
PLL directly and register it as a clock provider. Use lcdc_clk as a
pixel clock for the LCDC.

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/650280/
Link: https://lore.kernel.org/r/20250425-fd-mdp4-lvds-v4-3-6b212160b44c@oss.qualcomm.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.h b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.h
index 142ccb68b435263f91ba1ab27676e426d43e5d84..3d7ffd874e0d234f450f6170e623f87572456757 100644 (file)
--- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.h
+++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.h
@@ -207,6 +207,6 @@ static inline struct drm_encoder *mdp4_dsi_encoder_init(struct drm_device *dev)
 }
 #endif
 
-struct clk *mpd4_lvds_pll_init(struct drm_device *dev);
+struct clk *mpd4_get_lcdc_clock(struct drm_device *dev);
 
 #endif /* __MDP4_KMS_H__ */

diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lcdc_encoder.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lcdc_encoder.c
index 8bbc7fb881d599e7d309cc61bda83697fecd253a..8694e5d7d3f012070c72214df063a6488b2ef707 100644 (file)
--- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lcdc_encoder.c
+++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lcdc_encoder.c
@@ -380,8 +380,7 @@ struct drm_encoder *mdp4_lcdc_encoder_init(struct drm_device *dev,
 
        drm_encoder_helper_add(encoder, &mdp4_lcdc_encoder_helper_funcs);
 
-       /* TODO: do we need different pll in other cases? */
-       mdp4_lcdc_encoder->lcdc_clk = mpd4_lvds_pll_init(dev);
+       mdp4_lcdc_encoder->lcdc_clk = mpd4_get_lcdc_clock(dev);
        if (IS_ERR(mdp4_lcdc_encoder->lcdc_clk)) {
                DRM_DEV_ERROR(dev->dev, "failed to get lvds_clk\n");
                return ERR_CAST(mdp4_lcdc_encoder->lcdc_clk);

diff --git a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_pll.c b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_pll.c
index ab8c0c187fb2cd05e26f5019244af15f1b2470c8..df2bbd475cc2a11da20ac07be8e757527ef41ae8 100644 (file)
--- a/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_pll.c
+++ b/drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_pll.c
@@ -133,29 +133,48 @@ static struct clk_init_data pll_init = {
        .num_parents = ARRAY_SIZE(mpd4_lvds_pll_parents),
 };
 
-struct clk *mpd4_lvds_pll_init(struct drm_device *dev)
+static struct clk_hw *mpd4_lvds_pll_init(struct drm_device *dev)
 {
        struct mdp4_lvds_pll *lvds_pll;
-       struct clk *clk;
        int ret;
 
        lvds_pll = devm_kzalloc(dev->dev, sizeof(*lvds_pll), GFP_KERNEL);
-       if (!lvds_pll) {
-               ret = -ENOMEM;
-               goto fail;
-       }
+       if (!lvds_pll)
+               return ERR_PTR(-ENOMEM);
 
        lvds_pll->dev = dev;
 
        lvds_pll->pll_hw.init = &pll_init;
-       clk = devm_clk_register(dev->dev, &lvds_pll->pll_hw);
-       if (IS_ERR(clk)) {
-               ret = PTR_ERR(clk);
-               goto fail;
+       ret = devm_clk_hw_register(dev->dev, &lvds_pll->pll_hw);
+       if (ret)
+               return ERR_PTR(ret);
+
+       ret = devm_of_clk_add_hw_provider(dev->dev, of_clk_hw_simple_get, &lvds_pll->pll_hw);
+       if (ret)
+               return ERR_PTR(ret);
+
+       return &lvds_pll->pll_hw;
+}
+
+struct clk *mpd4_get_lcdc_clock(struct drm_device *dev)
+{
+       struct clk_hw *hw;
+       struct clk *clk;
+
+
+       /* TODO: do we need different pll in other cases? */
+       hw = mpd4_lvds_pll_init(dev);
+       if (IS_ERR(hw)) {
+               DRM_DEV_ERROR(dev->dev, "failed to register LVDS PLL\n");
+               return ERR_CAST(hw);
        }
 
-       return clk;
+       clk = devm_clk_get(dev->dev, "lcdc_clk");
+       if (clk == ERR_PTR(-ENOENT)) {
+               drm_warn(dev, "can't get LCDC clock, using PLL directly\n");
 
-fail:
-       return ERR_PTR(ret);
+               return devm_clk_hw_get_clk(dev->dev, hw, "lcdc_clk");
+       }
+
+       return clk;
 }