diff options
Diffstat (limited to 'drivers/media/video/uvc/uvc_debugfs.c')
-rw-r--r-- | drivers/media/video/uvc/uvc_debugfs.c | 136 |
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 00000000000..14561a5abb7 --- /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); +} |