Re: [PATCH] USB: move usb debugfs directory creation to the usb common core

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Tue, Jun 04, 2019 at 11:32:58AM +0200, Greg Kroah-Hartman wrote:
> The USB gadget subsystem wants to use the USB debugfs root directory, so
> move it to the common "core" USB code so that it is properly initialized
> and removed as needed.
> 
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> 
> ---
> 
> This should be the "correct" version of this, Chunfeng, can you test
> this to verify it works for you?
> 
> 
> diff --git a/drivers/usb/common/common.c b/drivers/usb/common/common.c
> index 18f5dcf58b0d..3b5e4263ffef 100644
> --- a/drivers/usb/common/common.c
> +++ b/drivers/usb/common/common.c
> @@ -15,6 +15,7 @@
>  #include <linux/usb/of.h>
>  #include <linux/usb/otg.h>
>  #include <linux/of_platform.h>
> +#include <linux/debugfs.h>
>  
>  static const char *const ep_type_names[] = {
>  	[USB_ENDPOINT_XFER_CONTROL] = "ctrl",
> @@ -291,4 +292,21 @@ struct device *usb_of_get_companion_dev(struct device *dev)
>  EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);
>  #endif
>  
> +struct dentry *usb_debug_root;
> +EXPORT_SYMBOL_GPL(usb_debug_root);
> +
> +static int usb_common_init(void)
> +{
> +	usb_debug_root = debugfs_create_dir("usb", NULL);
> +	return 0;
> +}
> +
> +static void usb_common_exit(void)
> +{
> +	debugfs_remove_recursive(usb_debug_root);
> +}
> +
> +module_init(usb_common_init);
> +module_exit(usb_common_exit);
> +
>  MODULE_LICENSE("GPL");
> diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
> index 7fcb9f782931..f3d6b1ab80cb 100644
> --- a/drivers/usb/core/usb.c
> +++ b/drivers/usb/core/usb.c
> @@ -1185,19 +1185,17 @@ static struct notifier_block usb_bus_nb = {
>  	.notifier_call = usb_bus_notify,
>  };
>  
> -struct dentry *usb_debug_root;
> -EXPORT_SYMBOL_GPL(usb_debug_root);
> +static struct dentry *usb_devices_root;
>  
>  static void usb_debugfs_init(void)
>  {
> -	usb_debug_root = debugfs_create_dir("usb", NULL);
> -	debugfs_create_file("devices", 0444, usb_debug_root, NULL,
> -			    &usbfs_devices_fops);
> +	usb_devices_root = debugfs_create_file("devices", 0444, usb_debug_root,
> +					       NULL, &usbfs_devices_fops);
>  }
>  
>  static void usb_debugfs_cleanup(void)
>  {
> -	debugfs_remove_recursive(usb_debug_root);
> +	debugfs_remove_recursive(usb_devices_root);

That should just be debugfs_remove();

I'll fix it up after someone tests this :)

thanks,

greg k-h