From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754786Ab1JKOIt (ORCPT ); Tue, 11 Oct 2011 10:08:49 -0400 Received: from na3sys009aog114.obsmtp.com ([74.125.149.211]:35190 "EHLO na3sys009aog114.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754695Ab1JKOIr (ORCPT ); Tue, 11 Oct 2011 10:08:47 -0400 Date: Tue, 11 Oct 2011 17:08:40 +0300 From: Felipe Balbi To: Alan Stern Cc: Felipe Balbi , "Munegowda, Keshava" , Paul Walmsley , linux-usb@vger.kernel.org, linux-omap@vger.kernel.org, linux-kernel@vger.kernel.org, khilman@ti.com, b-cousson@ti.com, gadiyar@ti.com, sameo@linux.intel.com, parthab@india.ti.com, tony@atomide.com, johnstul@us.ibm.com, vishwanath.bs@ti.com, Greg KH Subject: Re: [PATCH 1/5 v13] arm: omap: usb: ehci and ohci hwmod structures for omap4 Message-ID: <20111011140839.GF12293@legolas.emea.dhcp.ti.com> Reply-To: balbi@ti.com References: <20111011081352.GC10155@legolas.emea.dhcp.ti.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="SnV5plBeK2Ge1I9g" Content-Disposition: inline In-Reply-To: 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 --SnV5plBeK2Ge1I9g Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi, On Tue, Oct 11, 2011 at 10:04:28AM -0400, Alan Stern wrote: > On Tue, 11 Oct 2011, Felipe Balbi wrote: >=20 > > > > It doesn't shown here, but the TLL link is completely optional. It's > > > > mainly used for modem integration, IIRC. Still, if we're using TLL,= EHCI > > > > and OHCI will depend on a clock provided by the USBTLL block. > > > >=20 > > > > Clearly, USBTLL isn't either a parent of UHH, nor a parent of EHCI/= OHCI > > > > blocks. We can, from a code perspective, make USBTLL into a parent = of > > > > UHH to make things simpler, but this will mean that calling > > > > pm_runtime_get() will also unconditionaly turn on TLL clock, unless= we > > > > add some nasty hacks to allow TLL know if *HCI port is in TLL mode. > > > >=20 > > > > That's why I decided for making TLL and UHH siblings, because that'= s a > > > > closer relationship than parent-child. > > > >=20 > > > > Can you see the problem now ? > > >=20 > > > Okay, now I understand better. The word "sibling" implies that the t= wo=20 > > > objects have the same parent, so a different word would describe this= =20 > > > relationship better. Something like "friend" or "associate". > > >=20 > > > Or maybe, following Paul's suggestion, the driver core doesn't have t= o=20 > > > be changed at all. > >=20 > > I see... I just thought that if there are other similar cases, it might > > make sense to have a more generic way to make those two devices talk to > > each other. But if you all agree that an EXPORT_SYMBOL_GPL() is enough, > > then it's ok ;-) >=20 > At the moment, I can't see any way to set up a more generic mechanism=20 > that wouldn't be more complicated and have higher overhead than a=20 > simple EXPORT_SYMBOL_GPL. >=20 > Can this be handled by adding another resource to a platform_device? =20 > That at least would make use of an already-existing mechanism. maybe, but let's go with EXPORT_SYMBOL_GPL(). My only concern is that this IP comes from synopsys, and I'm not really keen on adding OMAP-specific, integration-related knowledge on a driver which was supposed to be reusable ;-) But at least for the time being, I guess that's what we need to do ;-) tks --=20 balbi --SnV5plBeK2Ge1I9g Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAEBAgAGBQJOlE3mAAoJEIaOsuA1yqREHBYP+gLYkqMQwsIv6eKT5unX7/rU c8vRnCgpcxDUo3sXHLvZe98E0DaXOX6AwdKrfYAgsAk0ZTYth/vts4DHNeDW6Q64 7wj1WncYXsreDJ/EIJ93L5/DH+uCM+9wy0d7ZITM3R6I8u9geNUoRTj4Ni+MaOlN rEm2zIPzYc/4x2IFTKSe8TyqZXe9cy1NVRr3Z21aURaRJ8LiLM2MSR+5vAgZjlyg 5sii6Wga/FBN7YPshCOwTLcL+v92d5MCJtGQnVxnDA8uwqNfeEa5WClqAjvHL7LZ g4DkNYli/AayInWwT4aLwlzL1+wuopMQOyVWp2/0c0v/A6t9rvbBj9Lk1d1zVHKh RAOxcqHh8KmUZfY7u0AQ150z7CpRxZAWOJltgHt72AE5KjOX7YwllRxTYsjSCGRk mMQoLZssBLobUrdEZAx36kirnv01DrV1IdLnxt6Gh2+Ew6/vd7214RAejjBrPcWl LG3K0FmkrbWWr7UJO0Mp+R//+cCInogO99f/qQMr1HqXEkZyBSGQHif2uIsvVEd1 lQ0rCbNiN/dS7Vimon0SOCPZLGp3U+bUi+PzZKcCmbWij30RfRttkuAU7/nwdTbH +xdZXiEF1warSYZDwgpwFa22DZZpICe0EPiJuRiLru4rvTHKH9dN0TCo14+f2C+t rbCuh22qU+YYW9rhZL8P =jJvq -----END PGP SIGNATURE----- --SnV5plBeK2Ge1I9g--