From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Subject: Re: [RFC/PATCH 2/2] driver core: power management debugging Date: Sat, 28 Apr 2007 23:50:51 -0700 Message-ID: <20070429065051.GA31628@kroah.com> References: <1177800952.7652.4.camel@nigel.suspend2.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1177800952.7652.4.camel@nigel.suspend2.net> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: Nigel Cunningham Cc: linux-pm@lists.osdl.org, Pekka J Enberg , pavel@ucw.cz List-Id: linux-pm@vger.kernel.org On Sun, Apr 29, 2007 at 08:55:52AM +1000, Nigel Cunningham wrote: > Hi. > > On Sat, 2007-04-28 at 10:42 -0400, Alan Stern wrote: > > On Sat, 28 Apr 2007, Nigel Cunningham wrote: > > > > > Hi Alan. > > > > > Sorry. I thought you were wrong for a minute, but then I looked again at > > > the messages in my dmesg... > > > > > > [ 33.944214] Device driver usbdev1.1_ep00 lacks bus and class support for being resumed. > > > [ 34.051765] Device driver usbdev1.1_ep81 lacks bus and class support for being resumed. > > > [ 34.113740] Device driver usbdev2.1_ep00 lacks bus and class support for being resumed. > > > [ 34.221541] Device driver usbdev2.1_ep81 lacks bus and class support for being resumed. > > > [ 34.251562] Device driver usbdev3.1_ep00 lacks bus and class support for being resumed. > > > [ 34.361345] Device driver usbdev3.1_ep81 lacks bus and class support for being resumed. > > > > > > They're coming from the other printk, of course. > > > > > > > Now perhaps you would prefer to check the USB interface drivers -- there > > > > are many of them, and quite a few don't have suspend or resume methods. > > > > You would need to modify usb_register_driver() instead of > > > > usb_register_device_driver(). > > > > > > Would they be the ones covered above? > > > > No. As Greg pointed out, these usbdevXX_epYY "devices" are nothing but > > placeholders at the moment. They don't actually do anything and they have > > no need for power management. (But they do manage to clutter up the > > system log with lots of extraneous warnings from the PM core...) > > Ok, so they could have the pm_safe flag set to suppress the message. No, we don't want a flag just to shut up a message, that's the first thing a developer will do when they see that message, without realizing what exactly they should be doing instead. Trust me, I know the lengths kernel developers go to to try to work around "helpful hints" that the kernel can spit out at you :( thanks, greg k-h