1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * uvc_debugfs.c -- USB Video Class driver - Debugging support
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (C) 2011
6*4882a593Smuzhiyun * Laurent Pinchart (laurent.pinchart@ideasonboard.com)
7*4882a593Smuzhiyun */
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun #include <linux/module.h>
10*4882a593Smuzhiyun #include <linux/debugfs.h>
11*4882a593Smuzhiyun #include <linux/slab.h>
12*4882a593Smuzhiyun #include <linux/usb.h>
13*4882a593Smuzhiyun
14*4882a593Smuzhiyun #include "uvcvideo.h"
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun /* -----------------------------------------------------------------------------
17*4882a593Smuzhiyun * Statistics
18*4882a593Smuzhiyun */
19*4882a593Smuzhiyun
20*4882a593Smuzhiyun #define UVC_DEBUGFS_BUF_SIZE 1024
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun struct uvc_debugfs_buffer {
23*4882a593Smuzhiyun size_t count;
24*4882a593Smuzhiyun char data[UVC_DEBUGFS_BUF_SIZE];
25*4882a593Smuzhiyun };
26*4882a593Smuzhiyun
uvc_debugfs_stats_open(struct inode * inode,struct file * file)27*4882a593Smuzhiyun static int uvc_debugfs_stats_open(struct inode *inode, struct file *file)
28*4882a593Smuzhiyun {
29*4882a593Smuzhiyun struct uvc_streaming *stream = inode->i_private;
30*4882a593Smuzhiyun struct uvc_debugfs_buffer *buf;
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun buf = kmalloc(sizeof(*buf), GFP_KERNEL);
33*4882a593Smuzhiyun if (buf == NULL)
34*4882a593Smuzhiyun return -ENOMEM;
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun buf->count = uvc_video_stats_dump(stream, buf->data, sizeof(buf->data));
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun file->private_data = buf;
39*4882a593Smuzhiyun return 0;
40*4882a593Smuzhiyun }
41*4882a593Smuzhiyun
uvc_debugfs_stats_read(struct file * file,char __user * user_buf,size_t nbytes,loff_t * ppos)42*4882a593Smuzhiyun static ssize_t uvc_debugfs_stats_read(struct file *file, char __user *user_buf,
43*4882a593Smuzhiyun size_t nbytes, loff_t *ppos)
44*4882a593Smuzhiyun {
45*4882a593Smuzhiyun struct uvc_debugfs_buffer *buf = file->private_data;
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun return simple_read_from_buffer(user_buf, nbytes, ppos, buf->data,
48*4882a593Smuzhiyun buf->count);
49*4882a593Smuzhiyun }
50*4882a593Smuzhiyun
uvc_debugfs_stats_release(struct inode * inode,struct file * file)51*4882a593Smuzhiyun static int uvc_debugfs_stats_release(struct inode *inode, struct file *file)
52*4882a593Smuzhiyun {
53*4882a593Smuzhiyun kfree(file->private_data);
54*4882a593Smuzhiyun file->private_data = NULL;
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun return 0;
57*4882a593Smuzhiyun }
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun static const struct file_operations uvc_debugfs_stats_fops = {
60*4882a593Smuzhiyun .owner = THIS_MODULE,
61*4882a593Smuzhiyun .open = uvc_debugfs_stats_open,
62*4882a593Smuzhiyun .llseek = no_llseek,
63*4882a593Smuzhiyun .read = uvc_debugfs_stats_read,
64*4882a593Smuzhiyun .release = uvc_debugfs_stats_release,
65*4882a593Smuzhiyun };
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun /* -----------------------------------------------------------------------------
68*4882a593Smuzhiyun * Global and stream initialization/cleanup
69*4882a593Smuzhiyun */
70*4882a593Smuzhiyun
71*4882a593Smuzhiyun static struct dentry *uvc_debugfs_root_dir;
72*4882a593Smuzhiyun
uvc_debugfs_init_stream(struct uvc_streaming * stream)73*4882a593Smuzhiyun void uvc_debugfs_init_stream(struct uvc_streaming *stream)
74*4882a593Smuzhiyun {
75*4882a593Smuzhiyun struct usb_device *udev = stream->dev->udev;
76*4882a593Smuzhiyun char dir_name[33];
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun if (uvc_debugfs_root_dir == NULL)
79*4882a593Smuzhiyun return;
80*4882a593Smuzhiyun
81*4882a593Smuzhiyun snprintf(dir_name, sizeof(dir_name), "%u-%u-%u", udev->bus->busnum,
82*4882a593Smuzhiyun udev->devnum, stream->intfnum);
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun stream->debugfs_dir = debugfs_create_dir(dir_name,
85*4882a593Smuzhiyun uvc_debugfs_root_dir);
86*4882a593Smuzhiyun
87*4882a593Smuzhiyun debugfs_create_file("stats", 0444, stream->debugfs_dir, stream,
88*4882a593Smuzhiyun &uvc_debugfs_stats_fops);
89*4882a593Smuzhiyun }
90*4882a593Smuzhiyun
uvc_debugfs_cleanup_stream(struct uvc_streaming * stream)91*4882a593Smuzhiyun void uvc_debugfs_cleanup_stream(struct uvc_streaming *stream)
92*4882a593Smuzhiyun {
93*4882a593Smuzhiyun debugfs_remove_recursive(stream->debugfs_dir);
94*4882a593Smuzhiyun stream->debugfs_dir = NULL;
95*4882a593Smuzhiyun }
96*4882a593Smuzhiyun
uvc_debugfs_init(void)97*4882a593Smuzhiyun void uvc_debugfs_init(void)
98*4882a593Smuzhiyun {
99*4882a593Smuzhiyun uvc_debugfs_root_dir = debugfs_create_dir("uvcvideo", usb_debug_root);
100*4882a593Smuzhiyun }
101*4882a593Smuzhiyun
uvc_debugfs_cleanup(void)102*4882a593Smuzhiyun void uvc_debugfs_cleanup(void)
103*4882a593Smuzhiyun {
104*4882a593Smuzhiyun debugfs_remove_recursive(uvc_debugfs_root_dir);
105*4882a593Smuzhiyun }
106