drm: Convert proc files to seq_file and introduce debugfs

The old mechanism to formatting proc files is extremely ugly. The
seq_file API was designed specifically for cases like this and greatly
simplifies the process.

Also, most of the files in /proc really don't belong there. This patch
introduces the infrastructure for putting these into debugfs and exposes
all of the proc files in debugfs as well.

Signed-off-by: Ben Gamari <bgamari@gmail.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c
index 7c8b15b..48f33be 100644
--- a/drivers/gpu/drm/drm_stub.c
+++ b/drivers/gpu/drm/drm_stub.c
@@ -50,6 +50,7 @@
 
 struct class *drm_class;
 struct proc_dir_entry *drm_proc_root;
+struct dentry *drm_debugfs_root;
 
 static int drm_minor_get_id(struct drm_device *dev, int type)
 {
@@ -313,7 +314,15 @@
 			goto err_mem;
 		}
 	} else
-		new_minor->dev_root = NULL;
+		new_minor->proc_root = NULL;
+
+#if defined(CONFIG_DEBUG_FS)
+	ret = drm_debugfs_init(new_minor, minor_id, drm_debugfs_root);
+	if (ret) {
+		DRM_ERROR("DRM: Failed to initialize /debugfs/dri.\n");
+		goto err_g2;
+	}
+#endif
 
 	ret = drm_sysfs_device_add(new_minor);
 	if (ret) {
@@ -451,6 +460,10 @@
 
 	if (minor->type == DRM_MINOR_LEGACY)
 		drm_proc_cleanup(minor, drm_proc_root);
+#if defined(CONFIG_DEBUG_FS)
+	drm_debugfs_cleanup(minor);
+#endif
+
 	drm_sysfs_device_remove(minor);
 
 	idr_remove(&drm_minors_idr, minor->index);