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path: root/drivers/media/usb/uvc/uvc_debugfs.c
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Diffstat (limited to 'drivers/media/usb/uvc/uvc_debugfs.c')
-rw-r--r--drivers/media/usb/uvc/uvc_debugfs.c136
1 files changed, 136 insertions, 0 deletions
diff --git a/drivers/media/usb/uvc/uvc_debugfs.c b/drivers/media/usb/uvc/uvc_debugfs.c
new file mode 100644
index 000000000000..14561a5abb79
--- /dev/null
+++ b/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);
+}