1 files changed, 136 insertions, 0 deletions

diff --git a/drivers/media/video/uvc/uvc_debugfs.c b/drivers/media/video/uvc/uvc_debugfs.c
new file mode 100644
index 000000000000..14561a5abb79
--- /dev/null
+++ b/drivers/media/video/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);
+}