From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Kroah-Hartman Subject: Re: [PATCH v4] usb: create usb_debug_root for gadget only Date: Tue, 4 Jun 2019 10:24:07 +0200 Message-ID: <20190604082407.GA3783@kroah.com> References: <1559633647-29040-1-git-send-email-chunfeng.yun@mediatek.com> <20190604073706.GA25045@kroah.com> <87k1e123mc.fsf@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <87k1e123mc.fsf@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org To: Felipe Balbi Cc: Chunfeng Yun , Matthias Brugger , linux-usb@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org List-Id: linux-mediatek@lists.infradead.org On Tue, Jun 04, 2019 at 10:47:55AM +0300, Felipe Balbi wrote: > > Hi, > > Greg Kroah-Hartman writes: > >> +struct dentry *usb_debugfs_init(void) > >> +{ > >> + if (!usb_debug_root) > >> + usb_debug_root = debugfs_create_dir("usb", NULL); > >> + > >> + atomic_inc(&usb_debug_root_refcnt); > >> + > >> + return usb_debug_root; > >> +} > >> +EXPORT_SYMBOL_GPL(usb_debugfs_init); > >> + > >> +void usb_debugfs_cleanup(void) > >> +{ > >> + if (atomic_dec_and_test(&usb_debug_root_refcnt)) { > >> + debugfs_remove_recursive(usb_debug_root); > >> + usb_debug_root = NULL; > >> + } > >> +} > >> +EXPORT_SYMBOL_GPL(usb_debugfs_cleanup); > > > > Only remove the debugfs subdir if the usbcore module is removed. Create > > the debugfs subdir when the usbcore module is loaded. No need for any > > reference counting of any sort at all. No need to overthink this :) > > There is a slight need to overthink. He wants to use the same directory > for gadget-only builds too :-) Again, that's fine, this file will be loaded for those builds as well, right? Otherwise, how would this code even be present? :) thanks, greg k-h