drm/bridge/synopsys: stop clobbering drvdata

Bridge drivers/helpers shouldn't be clobbering the drvdata, since a
parent driver might need to own this. Instead, let's return our
'dw_mipi_dsi' object and have callers pass that back to us for removal.
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Archit Taneja <architt@codeaurora.org>
Acked-by: Philippe Cornu <philippe.cornu@st.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171128010538.119114-1-briannorris@chromium.org

drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c

@@ -922,8 +922,6 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
 	dsi->bridge.of_node = pdev->dev.of_node;
 #endif
 
-	dev_set_drvdata(dev, dsi);
-
 	return dsi;
 }
 
@@ -935,23 +933,16 @@ static void __dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi)
 /*
  * Probe/remove API, used from platforms based on the DRM bridge API.
  */
-int dw_mipi_dsi_probe(struct platform_device *pdev,
-		      const struct dw_mipi_dsi_plat_data *plat_data)
+struct dw_mipi_dsi *
+dw_mipi_dsi_probe(struct platform_device *pdev,
+		  const struct dw_mipi_dsi_plat_data *plat_data)
 {
-	struct dw_mipi_dsi *dsi;
-
-	dsi = __dw_mipi_dsi_probe(pdev, plat_data);
-	if (IS_ERR(dsi))
-		return PTR_ERR(dsi);
-
-	return 0;
+	return __dw_mipi_dsi_probe(pdev, plat_data);
 }
 EXPORT_SYMBOL_GPL(dw_mipi_dsi_probe);
 
-void dw_mipi_dsi_remove(struct platform_device *pdev)
+void dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi)
 {
-	struct dw_mipi_dsi *dsi = platform_get_drvdata(pdev);
-
 	mipi_dsi_host_unregister(&dsi->dsi_host);
 
 	__dw_mipi_dsi_remove(dsi);
@@ -961,31 +952,30 @@ EXPORT_SYMBOL_GPL(dw_mipi_dsi_remove);
 /*
  * Bind/unbind API, used from platforms based on the component framework.
  */
-int dw_mipi_dsi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
-		     const struct dw_mipi_dsi_plat_data *plat_data)
+struct dw_mipi_dsi *
+dw_mipi_dsi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
+		 const struct dw_mipi_dsi_plat_data *plat_data)
 {
 	struct dw_mipi_dsi *dsi;
 	int ret;
 
 	dsi = __dw_mipi_dsi_probe(pdev, plat_data);
 	if (IS_ERR(dsi))
-		return PTR_ERR(dsi);
+		return dsi;
 
 	ret = drm_bridge_attach(encoder, &dsi->bridge, NULL);
 	if (ret) {
-		dw_mipi_dsi_remove(pdev);
+		dw_mipi_dsi_remove(dsi);
 		DRM_ERROR("Failed to initialize bridge with drm\n");
-		return ret;
+		return ERR_PTR(ret);
 	}
 
-	return 0;
+	return dsi;
 }
 EXPORT_SYMBOL_GPL(dw_mipi_dsi_bind);
 
-void dw_mipi_dsi_unbind(struct device *dev)
+void dw_mipi_dsi_unbind(struct dw_mipi_dsi *dsi)
 {
-	struct dw_mipi_dsi *dsi = dev_get_drvdata(dev);
-
 	__dw_mipi_dsi_remove(dsi);
 }
 EXPORT_SYMBOL_GPL(dw_mipi_dsi_unbind);

drivers/gpu/drm/stm/dw_mipi_dsi-stm.c

@@ -65,6 +65,7 @@ enum dsi_color {
 struct dw_mipi_dsi_stm {
 	void __iomem *base;
 	struct clk *pllref_clk;
+	struct dw_mipi_dsi *dsi;
 };
 
 static inline void dsi_write(struct dw_mipi_dsi_stm *dsi, u32 reg, u32 val)
@@ -312,21 +313,24 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
 	dw_mipi_dsi_stm_plat_data.base = dsi->base;
 	dw_mipi_dsi_stm_plat_data.priv_data = dsi;
 
-	ret = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
-	if (ret) {
+	platform_set_drvdata(pdev, dsi);
+
+	dsi->dsi = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
+	if (IS_ERR(dsi->dsi)) {
 		DRM_ERROR("Failed to initialize mipi dsi host\n");
 		clk_disable_unprepare(dsi->pllref_clk);
+		return PTR_ERR(dsi->dsi);
 	}
 
-	return ret;
+	return 0;
 }
 
 static int dw_mipi_dsi_stm_remove(struct platform_device *pdev)
 {
-	struct dw_mipi_dsi_stm *dsi = dw_mipi_dsi_stm_plat_data.priv_data;
+	struct dw_mipi_dsi_stm *dsi = platform_get_drvdata(pdev);
 
 	clk_disable_unprepare(dsi->pllref_clk);
-	dw_mipi_dsi_remove(pdev);
+	dw_mipi_dsi_remove(dsi->dsi);
 
 	return 0;
 }

include/drm/bridge/dw_mipi_dsi.h

@@ -10,6 +10,8 @@
 #ifndef __DW_MIPI_DSI__
 #define __DW_MIPI_DSI__
 
+struct dw_mipi_dsi;
+
 struct dw_mipi_dsi_phy_ops {
 	int (*init)(void *priv_data);
 	int (*get_lane_mbps)(void *priv_data, struct drm_display_mode *mode,
@@ -29,11 +31,14 @@ struct dw_mipi_dsi_plat_data {
 	void *priv_data;
 };
 
-int dw_mipi_dsi_probe(struct platform_device *pdev,
-		      const struct dw_mipi_dsi_plat_data *plat_data);
-void dw_mipi_dsi_remove(struct platform_device *pdev);
-int dw_mipi_dsi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
-		     const struct dw_mipi_dsi_plat_data *plat_data);
-void dw_mipi_dsi_unbind(struct device *dev);
+struct dw_mipi_dsi *dw_mipi_dsi_probe(struct platform_device *pdev,
+				      const struct dw_mipi_dsi_plat_data
+				      *plat_data);
+void dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi);
+struct dw_mipi_dsi *dw_mipi_dsi_bind(struct platform_device *pdev,
+				     struct drm_encoder *encoder,
+				     const struct dw_mipi_dsi_plat_data
+				     *plat_data);
+void dw_mipi_dsi_unbind(struct dw_mipi_dsi *dsi);
 
 #endif /* __DW_MIPI_DSI__ */