From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oliver Neukum Subject: Re: question on flushing buffers and spinning down disk Date: Mon, 24 Sep 2007 18:47:17 +0200 Message-ID: <200709241847.17714.oliver@neukum.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-usb-devel-bounces@lists.sourceforge.net Errors-To: linux-usb-devel-bounces@lists.sourceforge.net To: Alan Stern Cc: James Bottomley , linux-usb-devel@lists.sourceforge.net, linux-scsi@vger.kernel.org List-Id: linux-scsi@vger.kernel.org Am Montag 24 September 2007 schrieb Alan Stern: > On Mon, 24 Sep 2007, Oliver Neukum wrote: > > > > suspend. The PM and driver cores don't include _any_ provision for > > > runtime suspend; it has to be managed separately by each subsystem. > > > > There we have a problem. We'd have to solve it for each subsystem transition. > > Storage has this type of children, other devices will have to care for other > > types of child devices. If we have a device tree, we should use it. > > It sounds like you want to add the equivalent of > usb_autopm_get/set_device() and usb_autopm_get/set_interface() into the That would be an ideal solution, but it is not necessary to solve this problem. > driver model. But it would not be appropriate, since other subsystems > don't have the same kinds of runtime power levels as USB does. But we don't bother when suspending the whole system. So why not simply walk the subtrees under a USB device? Let the subsystem choose what depth of sleep to use. > There may be no way of getting around the need for specialized > communication methods between subsystems for runtime PM. That's a lot of code duplication and should be a solution of last resort. Regards Oliver ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel