From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Subject: Re: [RFC PATCH] usb/acpi: Add support usb port power off mechanism for device fixed on the motherboard Date: Tue, 15 May 2012 08:18:00 -0700 Message-ID: <20120515151800.GC23916@kroah.com> References: <20120511202113.GH18754@xanatos> <20120511235922.GJ18754@xanatos> <20120512001722.GA28011@kroah.com> <20120514232123.GK18754@xanatos> <4FB268CA.9060304@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <4FB268CA.9060304-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Lan Tianyu Cc: Sarah Sharp , Alan Stern , Dan Williams , lenb-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-acpi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-acpi@vger.kernel.org On Tue, May 15, 2012 at 10:31:38PM +0800, Lan Tianyu wrote: > Since alan suggested we should start simpler version(power > down port that have no devices attached) firstly. And we > also should provide general power off mechanism. > > I have a proposal. > first: add portx_power_control sys file. > echo "auto" => portx_power_control > check whether there is a device. if no, send the clear > USB_PORT_FEAT_POWER request. (since general way > to control port power is via set or clear PORT_POWER) > > echo "on" => portx_power_control > send the set USB_PORT_FEAT_POWER request. No "off"? > second: > In the xhci driver, add acpi hook in the xhci_hub_control() > where USB_PORT_FEAT_POWER request is dealt with. Do you have a patch showing that this works? greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html