Fixed MTP to work with TWRP

drivers/media/usb/uvc/uvc_debugfs.c

@@ -0,0 +1,136 @@
+/*
+ *      uvc_debugfs.c --  USB Video Class driver - Debugging support
+ *
+ *      Copyright (C) 2011
+ *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+ *
+ *      This program is free software; you can redistribute it and/or modify
+ *      it under the terms of the GNU General Public License as published by
+ *      the Free Software Foundation; either version 2 of the License, or
+ *      (at your option) any later version.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/debugfs.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+
+#include "uvcvideo.h"
+
+/* -----------------------------------------------------------------------------
+ * Statistics
+ */
+
+#define UVC_DEBUGFS_BUF_SIZE	1024
+
+struct uvc_debugfs_buffer {
+	size_t count;
+	char data[UVC_DEBUGFS_BUF_SIZE];
+};
+
+static int uvc_debugfs_stats_open(struct inode *inode, struct file *file)
+{
+	struct uvc_streaming *stream = inode->i_private;
+	struct uvc_debugfs_buffer *buf;
+
+	buf = kmalloc(sizeof(*buf), GFP_KERNEL);
+	if (buf == NULL)
+		return -ENOMEM;
+
+	buf->count = uvc_video_stats_dump(stream, buf->data, sizeof(buf->data));
+
+	file->private_data = buf;
+	return 0;
+}
+
+static ssize_t uvc_debugfs_stats_read(struct file *file, char __user *user_buf,
+				      size_t nbytes, loff_t *ppos)
+{
+	struct uvc_debugfs_buffer *buf = file->private_data;
+
+	return simple_read_from_buffer(user_buf, nbytes, ppos, buf->data,
+				       buf->count);
+}
+
+static int uvc_debugfs_stats_release(struct inode *inode, struct file *file)
+{
+	kfree(file->private_data);
+	file->private_data = NULL;
+
+	return 0;
+}
+
+static const struct file_operations uvc_debugfs_stats_fops = {
+	.owner = THIS_MODULE,
+	.open = uvc_debugfs_stats_open,
+	.llseek = no_llseek,
+	.read = uvc_debugfs_stats_read,
+	.release = uvc_debugfs_stats_release,
+};
+
+/* -----------------------------------------------------------------------------
+ * Global and stream initialization/cleanup
+ */
+
+static struct dentry *uvc_debugfs_root_dir;
+
+int uvc_debugfs_init_stream(struct uvc_streaming *stream)
+{
+	struct usb_device *udev = stream->dev->udev;
+	struct dentry *dent;
+	char dir_name[32];
+
+	if (uvc_debugfs_root_dir == NULL)
+		return -ENODEV;
+
+	sprintf(dir_name, "%u-%u", udev->bus->busnum, udev->devnum);
+
+	dent = debugfs_create_dir(dir_name, uvc_debugfs_root_dir);
+	if (IS_ERR_OR_NULL(dent)) {
+		uvc_printk(KERN_INFO, "Unable to create debugfs %s "
+			   "directory.\n", dir_name);
+		return -ENODEV;
+	}
+
+	stream->debugfs_dir = dent;
+
+	dent = debugfs_create_file("stats", 0444, stream->debugfs_dir,
+				   stream, &uvc_debugfs_stats_fops);
+	if (IS_ERR_OR_NULL(dent)) {
+		uvc_printk(KERN_INFO, "Unable to create debugfs stats file.\n");
+		uvc_debugfs_cleanup_stream(stream);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+void uvc_debugfs_cleanup_stream(struct uvc_streaming *stream)
+{
+	if (stream->debugfs_dir == NULL)
+		return;
+
+	debugfs_remove_recursive(stream->debugfs_dir);
+	stream->debugfs_dir = NULL;
+}
+
+int uvc_debugfs_init(void)
+{
+	struct dentry *dir;
+
+	dir = debugfs_create_dir("uvcvideo", usb_debug_root);
+	if (IS_ERR_OR_NULL(dir)) {
+		uvc_printk(KERN_INFO, "Unable to create debugfs directory\n");
+		return -ENODATA;
+	}
+
+	uvc_debugfs_root_dir = dir;
+	return 0;
+}
+
+void uvc_debugfs_cleanup(void)
+{
+	if (uvc_debugfs_root_dir != NULL)
+		debugfs_remove_recursive(uvc_debugfs_root_dir);
+}