drm/msm/dp: Drop unused dp_debug struct

The members of struct dp_debug are no longer used, so the only purpose
of this struct is as a type of the return value of dp_debug_get(), to
signal success/error.

Drop the struct in favor of signalling the result of initialization
using an int, then merge dp_debug_get() with dp_debug_init() to avoid
the unnecessar boilerplate code.
Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/585343/
Link: https://lore.kernel.org/r/20240328-msm-dp-cleanup-v2-1-a5aed9798d32@quicinc.comSigned-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

drivers/gpu/drm/msm/dp/dp_debug.c

@@ -21,8 +21,6 @@ struct dp_debug_private {
 	struct dp_link *link;
 	struct dp_panel *panel;
 	struct drm_connector *connector;
-
-	struct dp_debug dp_debug;
 };
 
 static int dp_debug_show(struct seq_file *seq, void *p)
@@ -199,10 +197,24 @@ static const struct file_operations test_active_fops = {
 	.write = dp_test_active_write
 };
 
-static void dp_debug_init(struct dp_debug *dp_debug, struct dentry *root, bool is_edp)
+int dp_debug_init(struct device *dev, struct dp_panel *panel,
+		  struct dp_link *link,
+		  struct drm_connector *connector,
+		  struct dentry *root, bool is_edp)
 {
-	struct dp_debug_private *debug = container_of(dp_debug,
-			struct dp_debug_private, dp_debug);
+	struct dp_debug_private *debug;
+
+	if (!dev || !panel || !link) {
+		DRM_ERROR("invalid input\n");
+		return -EINVAL;
+	}
+
+	debug = devm_kzalloc(dev, sizeof(*debug), GFP_KERNEL);
+	if (!debug)
+		return -ENOMEM;
+
+	debug->link = link;
+	debug->panel = panel;
 
 	debugfs_create_file("dp_debug", 0444, root,
 			debug, &dp_debug_fops);
@@ -220,41 +232,6 @@ static void dp_debug_init(struct dp_debug *dp_debug, struct dentry *root, bool i
 				    root,
 				    debug, &dp_test_type_fops);
 	}
-}
 
-struct dp_debug *dp_debug_get(struct device *dev, struct dp_panel *panel,
-		struct dp_link *link,
-		struct drm_connector *connector,
-		struct dentry *root, bool is_edp)
-{
-	struct dp_debug_private *debug;
-	struct dp_debug *dp_debug;
-	int rc;
-
-	if (!dev || !panel || !link) {
-		DRM_ERROR("invalid input\n");
-		rc = -EINVAL;
-		goto error;
-	}
-
-	debug = devm_kzalloc(dev, sizeof(*debug), GFP_KERNEL);
-	if (!debug) {
-		rc = -ENOMEM;
-		goto error;
-	}
-
-	debug->dp_debug.debug_en = false;
-	debug->link = link;
-	debug->panel = panel;
-
-	dp_debug = &debug->dp_debug;
-	dp_debug->vdisplay = 0;
-	dp_debug->hdisplay = 0;
-	dp_debug->vrefresh = 0;
-
-	dp_debug_init(dp_debug, root, is_edp);
-
-	return dp_debug;
- error:
-	return ERR_PTR(rc);
+	return 0;
 }

drivers/gpu/drm/msm/dp/dp_debug.h

@@ -9,22 +9,6 @@
 #include "dp_panel.h"
 #include "dp_link.h"
 
-/**
- * struct dp_debug
- * @debug_en: specifies whether debug mode enabled
- * @vdisplay: used to filter out vdisplay value
- * @hdisplay: used to filter out hdisplay value
- * @vrefresh: used to filter out vrefresh value
- * @tpg_state: specifies whether tpg feature is enabled
- */
-struct dp_debug {
-	bool debug_en;
-	int aspect_ratio;
-	int vdisplay;
-	int hdisplay;
-	int vrefresh;
-};
-
 #if defined(CONFIG_DEBUG_FS)
 
 /**
@@ -41,22 +25,22 @@ struct dp_debug {
  * This function sets up the debug module and provides a way
  * for debugfs input to be communicated with existing modules
  */
-struct dp_debug *dp_debug_get(struct device *dev, struct dp_panel *panel,
-		struct dp_link *link,
-		struct drm_connector *connector,
-		struct dentry *root,
-		bool is_edp);
+int dp_debug_init(struct device *dev, struct dp_panel *panel,
+		  struct dp_link *link,
+		  struct drm_connector *connector,
+		  struct dentry *root,
+		  bool is_edp);
 
 #else
 
 static inline
-struct dp_debug *dp_debug_get(struct device *dev, struct dp_panel *panel,
-		struct dp_link *link,
-		struct drm_connector *connector,
-		struct dentry *root,
-		bool is_edp)
+int dp_debug_init(struct device *dev, struct dp_panel *panel,
+		  struct dp_link *link,
+		  struct drm_connector *connector,
+		  struct dentry *root,
+		  bool is_edp)
 {
-	return ERR_PTR(-EINVAL);
+	return -EINVAL;
 }
 
 #endif /* defined(CONFIG_DEBUG_FS) */

drivers/gpu/drm/msm/dp/dp_display.c

@@ -93,7 +93,6 @@ struct dp_display_private {
 	struct dp_link    *link;
 	struct dp_panel   *panel;
 	struct dp_ctrl    *ctrl;
-	struct dp_debug   *debug;
 
 	struct dp_display_mode dp_mode;
 	struct msm_dp dp_display;
@@ -1459,14 +1458,9 @@ void dp_display_debugfs_init(struct msm_dp *dp_display, struct dentry *root, boo
 	dp = container_of(dp_display, struct dp_display_private, dp_display);
 	dev = &dp->dp_display.pdev->dev;
 
-	dp->debug = dp_debug_get(dev, dp->panel,
-					dp->link, dp->dp_display.connector,
-					root, is_edp);
-	if (IS_ERR(dp->debug)) {
-		rc = PTR_ERR(dp->debug);
+	rc = dp_debug_init(dev, dp->panel, dp->link, dp->dp_display.connector, root, is_edp);
+	if (rc)
 		DRM_ERROR("failed to initialize debug, rc = %d\n", rc);
-		dp->debug = NULL;
-	}
 }
 
 int msm_dp_modeset_init(struct msm_dp *dp_display, struct drm_device *dev,