From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753098Ab3GCNP7 (ORCPT ); Wed, 3 Jul 2013 09:15:59 -0400 Received: from devils.ext.ti.com ([198.47.26.153]:57296 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750851Ab3GCNP5 (ORCPT ); Wed, 3 Jul 2013 09:15:57 -0400 Date: Wed, 3 Jul 2013 16:15:13 +0300 From: Felipe Balbi To: Roger Quadros CC: , Alan Stern , , , , , , Subject: Re: [RFC PATCH 4/6] USB: ehci-omap: Suspend the controller during bus suspend Message-ID: <20130703131513.GH15056@arwen.pp.htv.fi> Reply-To: References: <51D28DB9.704@ti.com> <20130703125719.GD15056@arwen.pp.htv.fi> <51D421BC.9050600@ti.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="GBDnBH7+ZvLx8QD4" Content-Disposition: inline In-Reply-To: <51D421BC.9050600@ti.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --GBDnBH7+ZvLx8QD4 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Jul 03, 2013 at 04:06:04PM +0300, Roger Quadros wrote: > On 07/03/2013 03:57 PM, Felipe Balbi wrote: > > Hi, > >=20 > > On Tue, Jul 02, 2013 at 01:17:58PM -0400, Alan Stern wrote: > >> A PCI-based EHCI controller has two power sources: the core well (which > >> is turned off during suspend) and the auxiliary well (which remains > >> powered). That's how remote wakeup works; it uses the auxiliary well. > >=20 > > This, kinda, matches what OMAP tries to do with pad wakeup. Just that > > pad wakeup sits outside of the device itself. Perhaps we could look into > > how PCI handles the aux well and take some inspiration from there. > >=20 > > Any pointers under drivers/pci/ would be great :-) > >=20 > From what I understood, auxiliary well is just a power source, and it kee= ps > the EHCI controller powered even during suspend. >=20 > If that is true then it is different from our situation as we power down = the > EHCI controller completely. right but our "auxiliary well" keeps PRCM powered which can wake EHCI up ;-) What I'm saying is that from ehci-omap's perspective, there's very little difference, specially since we route the wakeup through the same IRQ line anyway. Perhaps we could take some inspiration from the PCI land to make our hwmod/omap_device a little easier from driver perspective. Or maybe it doesn't make sense ;-) --=20 balbi --GBDnBH7+ZvLx8QD4 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJR1CPhAAoJEIaOsuA1yqREXcUP/iz2iFfynbPWw5sT13z9TmVW 7AxHIe+AUaQKEVm4Ga9hSwH8SA/aatCBj2mGTU5jYtZt9dCOqknazXmZt0374i9H ZN9e421SGZLvNECeLnAqEXJhrGTUiGSpcaos34d1WHrS6UFQt9dQTKoNJa2M7I3p iw86nQ7wxKkY7i2smIpk3i8Ultr8ZJBJMyXdtGUgWPVQUBHV6ROouWhT5puD4UQm nQShMBRug/6tUp+H2pibTfc4eHCbeCkpSqm+mRziP2aAA/W/bPqQzZUFHfXMtxeR 4+Sbb1qh1oNLTK2xL4QRDo69mH+jT9N86rLYgBMjA4lxgzfZMFrmuvZ19cnIPvbZ E1tMlmKBuw+ZD1HTAi2kOxegUP77eZe40idi4x5BhTZSCryp5mfzFF4cJzq9Aohd uNYiBXU8gFwfNdJOck93MdjhCtpaL2kbyO9VuYhRDPN2rtfmtQ7YkgPk+c7MipPE GV/ask6WESRk+DyGwSJnRYfae6s6wJsUfj6x/Mjq0lxzzh3tSORV3iWNV8+c0xT2 ShNQnupQgGJ4AMtgALCu60SLDxere8vNhfXciWbk+X9nM5+p1e7FT4HDZPCLswpO qVtwYl3VDGZRugfXAvQtHDls32tTcj6e+YiGFKUpSqg7eVJHDFYRZ1K9l0t/QpT8 xN5VkpxsLDz6znd7ne/G =Jirn -----END PGP SIGNATURE----- --GBDnBH7+ZvLx8QD4--