drm/vc4: use new debugfs device-centered functions

Currently, vc4 has its own debugfs infrastructure that adds the debugfs
files on drm_dev_register(). With the introduction of the new debugfs,
functions, replace the vc4 debugfs structure with the DRM debugfs
device-centered function, drm_debugfs_add_file().

Moreover, remove the explicit error handling of debugfs related functions,
considering that the only failure mode is -ENOMEM and also that error
handling is not recommended for debugfs functions, as pointed out in [1].

[1] https://lore.kernel.org/all/YWAmZdRwnAt6wh9B@kroah.com/Signed-off-by: Maíra Canal <mcanal@igalia.com>
Reviewed-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Melissa Wen <mwen@igalia.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20221219120621.15086-5-mcanal@igalia.com

drivers/gpu/drm/vc4/vc4_bo.c

@@ -69,8 +69,8 @@ static void vc4_bo_stats_print(struct drm_printer *p, struct vc4_dev *vc4)
 
 static int vc4_bo_stats_debugfs(struct seq_file *m, void *unused)
 {
-	struct drm_info_node *node = (struct drm_info_node *)m->private;
-	struct drm_device *dev = node->minor->dev;
+	struct drm_debugfs_entry *entry = m->private;
+	struct drm_device *dev = entry->dev;
 	struct vc4_dev *vc4 = to_vc4_dev(dev);
 	struct drm_printer p = drm_seq_file_printer(m);
 
@@ -993,15 +993,11 @@ int vc4_bo_debugfs_init(struct drm_minor *minor)
 {
 	struct drm_device *drm = minor->dev;
 	struct vc4_dev *vc4 = to_vc4_dev(drm);
-	int ret;
 
 	if (!vc4->v3d)
 		return -ENODEV;
 
-	ret = vc4_debugfs_add_file(minor, "bo_stats",
-				   vc4_bo_stats_debugfs, NULL);
-	if (ret)
-		return ret;
+	drm_debugfs_add_file(drm, "bo_stats", vc4_bo_stats_debugfs, NULL);
 
 	return 0;
 }

drivers/gpu/drm/vc4/vc4_crtc.c

@@ -1090,12 +1090,9 @@ int vc4_crtc_late_register(struct drm_crtc *crtc)
 	struct drm_device *drm = crtc->dev;
 	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
 	const struct vc4_crtc_data *crtc_data = vc4_crtc_to_vc4_crtc_data(vc4_crtc);
-	int ret;
 
-	ret = vc4_debugfs_add_regset32(drm->primary, crtc_data->debugfs_name,
+	vc4_debugfs_add_regset32(drm, crtc_data->debugfs_name,
 				 &vc4_crtc->regset);
-	if (ret)
-		return ret;
 
 	return 0;
 }

drivers/gpu/drm/vc4/vc4_debugfs.c

@@ -34,9 +34,9 @@ vc4_debugfs_init(struct drm_minor *minor)
 
 static int vc4_debugfs_regset32(struct seq_file *m, void *unused)
 {
-	struct drm_info_node *node = (struct drm_info_node *)m->private;
-	struct drm_device *drm = node->minor->dev;
-	struct debugfs_regset32 *regset = node->info_ent->data;
+	struct drm_debugfs_entry *entry = m->private;
+	struct drm_device *drm = entry->dev;
+	struct debugfs_regset32 *regset = entry->file.data;
 	struct drm_printer p = drm_seq_file_printer(m);
 	int idx;
 
@@ -50,31 +50,9 @@ static int vc4_debugfs_regset32(struct seq_file *m, void *unused)
 	return 0;
 }
 
-int vc4_debugfs_add_file(struct drm_minor *minor,
-			 const char *name,
-			 int (*show)(struct seq_file*, void*),
-			 void *data)
-{
-	struct drm_device *dev = minor->dev;
-	struct dentry *root = minor->debugfs_root;
-	struct drm_info_list *file;
-
-	file = drmm_kzalloc(dev, sizeof(*file), GFP_KERNEL);
-	if (!file)
-		return -ENOMEM;
-
-	file->name = name;
-	file->show = show;
-	file->data = data;
-
-	drm_debugfs_create_files(file, 1, root, minor);
-
-	return 0;
-}
-
-int vc4_debugfs_add_regset32(struct drm_minor *minor,
+void vc4_debugfs_add_regset32(struct drm_device *drm,
 			      const char *name,
 			      struct debugfs_regset32 *regset)
 {
-	return vc4_debugfs_add_file(minor, name, vc4_debugfs_regset32, regset);
+	drm_debugfs_add_file(drm, name, vc4_debugfs_regset32, regset);
 }

drivers/gpu/drm/vc4/vc4_dpi.c

@@ -267,11 +267,8 @@ static int vc4_dpi_late_register(struct drm_encoder *encoder)
 {
 	struct drm_device *drm = encoder->dev;
 	struct vc4_dpi *dpi = to_vc4_dpi(encoder);
-	int ret;
 
-	ret = vc4_debugfs_add_regset32(drm->primary, "dpi_regs", &dpi->regset);
-	if (ret)
-		return ret;
+	vc4_debugfs_add_regset32(drm, "dpi_regs", &dpi->regset);
 
 	return 0;
 }

drivers/gpu/drm/vc4/vc4_drv.c

@@ -320,7 +320,6 @@ static int vc4_drm_bind(struct device *dev)
 
 	drm = &vc4->base;
 	platform_set_drvdata(pdev, drm);
-	INIT_LIST_HEAD(&vc4->debugfs_list);
 
 	if (!is_vc5) {
 		ret = drmm_mutex_init(drm, &vc4->bin_bo_lock);

drivers/gpu/drm/vc4/vc4_drv.h

@@ -226,11 +226,6 @@ struct vc4_dev {
 	struct drm_private_obj hvs_channels;
 	struct drm_private_obj load_tracker;
 
-	/* List of vc4_debugfs_info_entry for adding to debugfs once
-	 * the minor is available (after drm_dev_register()).
-	 */
-	struct list_head debugfs_list;
-
 	/* Mutex for binner bo allocation. */
 	struct mutex bin_bo_lock;
 	/* Reference count for our binner bo. */
@@ -971,28 +966,15 @@ void vc4_crtc_get_margins(struct drm_crtc_state *state,
 /* vc4_debugfs.c */
 void vc4_debugfs_init(struct drm_minor *minor);
 #ifdef CONFIG_DEBUG_FS
-int vc4_debugfs_add_file(struct drm_minor *minor,
-			 const char *filename,
-			 int (*show)(struct seq_file*, void*),
-			 void *data);
-int vc4_debugfs_add_regset32(struct drm_minor *minor,
+void vc4_debugfs_add_regset32(struct drm_device *drm,
 			      const char *filename,
 			      struct debugfs_regset32 *regset);
 #else
-static inline int vc4_debugfs_add_file(struct drm_minor *minor,
-				       const char *filename,
-				       int (*show)(struct seq_file*, void*),
-				       void *data)
-{
-	return 0;
-}
 
-static inline int vc4_debugfs_add_regset32(struct drm_minor *minor,
+static inline void vc4_debugfs_add_regset32(struct drm_device *drm,
 					    const char *filename,
 					    struct debugfs_regset32 *regset)
-{
-	return 0;
-}
+{}
 #endif
 
 /* vc4_drv.c */

drivers/gpu/drm/vc4/vc4_dsi.c

@@ -1427,12 +1427,8 @@ static int vc4_dsi_late_register(struct drm_encoder *encoder)
 {
 	struct drm_device *drm = encoder->dev;
 	struct vc4_dsi *dsi = to_vc4_dsi(encoder);
-	int ret;
 
-	ret = vc4_debugfs_add_regset32(drm->primary, dsi->variant->debugfs_name,
-				       &dsi->regset);
-	if (ret)
-		return ret;
+	vc4_debugfs_add_regset32(drm, dsi->variant->debugfs_name, &dsi->regset);
 
 	return 0;
 }

drivers/gpu/drm/vc4/vc4_hdmi.c

@@ -160,8 +160,8 @@ static bool vc4_hdmi_is_full_range_rgb(struct vc4_hdmi *vc4_hdmi,
 
 static int vc4_hdmi_debugfs_regs(struct seq_file *m, void *unused)
 {
-	struct drm_info_node *node = (struct drm_info_node *)m->private;
-	struct vc4_hdmi *vc4_hdmi = node->info_ent->data;
+	struct drm_debugfs_entry *entry = m->private;
+	struct vc4_hdmi *vc4_hdmi = entry->file.data;
 	struct drm_device *drm = vc4_hdmi->connector.dev;
 	struct drm_printer p = drm_seq_file_printer(m);
 	int idx;
@@ -1995,13 +1995,9 @@ static int vc4_hdmi_late_register(struct drm_encoder *encoder)
 	struct drm_device *drm = encoder->dev;
 	struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
 	const struct vc4_hdmi_variant *variant = vc4_hdmi->variant;
-	int ret;
 
-	ret = vc4_debugfs_add_file(drm->primary, variant->debugfs_name,
-				   vc4_hdmi_debugfs_regs,
-				   vc4_hdmi);
-	if (ret)
-		return ret;
+	drm_debugfs_add_file(drm, variant->debugfs_name,
+			     vc4_hdmi_debugfs_regs, vc4_hdmi);
 
 	return 0;
 }

drivers/gpu/drm/vc4/vc4_hvs.c

@@ -93,8 +93,8 @@ void vc4_hvs_dump_state(struct vc4_hvs *hvs)
 
 static int vc4_hvs_debugfs_underrun(struct seq_file *m, void *data)
 {
-	struct drm_info_node *node = m->private;
-	struct drm_device *dev = node->minor->dev;
+	struct drm_debugfs_entry *entry = m->private;
+	struct drm_device *dev = entry->dev;
 	struct vc4_dev *vc4 = to_vc4_dev(dev);
 	struct drm_printer p = drm_seq_file_printer(m);
 
@@ -105,8 +105,8 @@ static int vc4_hvs_debugfs_underrun(struct seq_file *m, void *data)
 
 static int vc4_hvs_debugfs_dlist(struct seq_file *m, void *data)
 {
-	struct drm_info_node *node = m->private;
-	struct drm_device *dev = node->minor->dev;
+	struct drm_debugfs_entry *entry = m->private;
+	struct drm_device *dev = entry->dev;
 	struct vc4_dev *vc4 = to_vc4_dev(dev);
 	struct vc4_hvs *hvs = vc4->hvs;
 	struct drm_printer p = drm_seq_file_printer(m);
@@ -740,7 +740,6 @@ int vc4_hvs_debugfs_init(struct drm_minor *minor)
 	struct drm_device *drm = minor->dev;
 	struct vc4_dev *vc4 = to_vc4_dev(drm);
 	struct vc4_hvs *hvs = vc4->hvs;
-	int ret;
 
 	if (!vc4->hvs)
 		return -ENODEV;
@@ -750,20 +749,11 @@ int vc4_hvs_debugfs_init(struct drm_minor *minor)
 				    minor->debugfs_root,
 				    &vc4->load_tracker_enabled);
 
-	ret = vc4_debugfs_add_file(minor, "hvs_dlists",
-				   vc4_hvs_debugfs_dlist, NULL);
-	if (ret)
-		return ret;
+	drm_debugfs_add_file(drm, "hvs_dlists", vc4_hvs_debugfs_dlist, NULL);
 
-	ret = vc4_debugfs_add_file(minor, "hvs_underrun",
-				   vc4_hvs_debugfs_underrun, NULL);
-	if (ret)
-		return ret;
+	drm_debugfs_add_file(drm, "hvs_underrun", vc4_hvs_debugfs_underrun, NULL);
 
-	ret = vc4_debugfs_add_regset32(minor, "hvs_regs",
-				       &hvs->regset);
-	if (ret)
-		return ret;
+	vc4_debugfs_add_regset32(drm, "hvs_regs", &hvs->regset);
 
 	return 0;
 }

drivers/gpu/drm/vc4/vc4_v3d.c

@@ -96,8 +96,8 @@ static const struct debugfs_reg32 v3d_regs[] = {
 
 static int vc4_v3d_debugfs_ident(struct seq_file *m, void *unused)
 {
-	struct drm_info_node *node = (struct drm_info_node *)m->private;
-	struct drm_device *dev = node->minor->dev;
+	struct drm_debugfs_entry *entry = m->private;
+	struct drm_device *dev = entry->dev;
 	struct vc4_dev *vc4 = to_vc4_dev(dev);
 	int ret = vc4_v3d_pm_get(vc4);
 
@@ -404,19 +404,13 @@ int vc4_v3d_debugfs_init(struct drm_minor *minor)
 	struct drm_device *drm = minor->dev;
 	struct vc4_dev *vc4 = to_vc4_dev(drm);
 	struct vc4_v3d *v3d = vc4->v3d;
-	int ret;
 
 	if (!vc4->v3d)
 		return -ENODEV;
 
-	ret = vc4_debugfs_add_file(minor, "v3d_ident",
-				   vc4_v3d_debugfs_ident, NULL);
-	if (ret)
-		return ret;
+	drm_debugfs_add_file(drm, "v3d_ident", vc4_v3d_debugfs_ident, NULL);
 
-	ret = vc4_debugfs_add_regset32(minor, "v3d_regs", &v3d->regset);
-	if (ret)
-		return ret;
+	vc4_debugfs_add_regset32(drm, "v3d_regs", &v3d->regset);
 
 	return 0;
 }

drivers/gpu/drm/vc4/vc4_vec.c

@@ -716,12 +716,8 @@ static int vc4_vec_late_register(struct drm_encoder *encoder)
 {
 	struct drm_device *drm = encoder->dev;
 	struct vc4_vec *vec = encoder_to_vc4_vec(encoder);
-	int ret;
 
-	ret = vc4_debugfs_add_regset32(drm->primary, "vec_regs",
-				       &vec->regset);
-	if (ret)
-		return ret;
+	vc4_debugfs_add_regset32(drm, "vec_regs", &vec->regset);
 
 	return 0;
 }