Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754672AbaAUOtB (ORCPT ); Tue, 21 Jan 2014 09:49:01 -0500 Received: from comal.ext.ti.com ([198.47.26.152]:46872 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754438AbaAUOs6 (ORCPT ); Tue, 21 Jan 2014 09:48:58 -0500 Date: Tue, 21 Jan 2014 08:47:25 -0600 From: Felipe Balbi To: Kishon Vijay Abraham I CC: , , , , , , , , , Subject: Re: [PATCH 1/2] usb: dwc3: core: continue probing if usb phy library returns -ENODEV/-ENXIO Message-ID: <20140121144725.GF30451@saruman.home> Reply-To: References: <1385373690-12170-1-git-send-email-kishon@ti.com> <1390299099-14764-1-git-send-email-kishon@ti.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="pyE8wggRBhVBcj8z" Content-Disposition: inline In-Reply-To: <1390299099-14764-1-git-send-email-kishon@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 --pyE8wggRBhVBcj8z Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Jan 21, 2014 at 03:41:38PM +0530, Kishon Vijay Abraham I wrote: > Since PHYs for dwc3 is optional (not all SoCs that have DWC3 use PHYs), > do not return from probe if the USB PHY library returns -ENODEV as that this isn't correct, they all have PHYs, some of them might not be controllable. > indicates the platform does not have PHY. not really, that indicates the current platform tried to grab a PHY and the PHY doesn't exist. If there's anybody with a non-controllable PHY and someone gives me a really good reason for not using the generic no-op PHY, then we should add a flag and we could: if (!likely(dwc->flags & DWC3_USB2PHY_DRIVER_NOT_NEEDED)) dwc3_grab_phys(dwc); But I really want to see the argument against using no-op. As far as I could see, everybody needs a PHY driver one way or another, some platforms just haven't sent any PHY driver upstream and have their own hacked up solution to avoid using the PHY layer. Your commit log really needs quite some extra work. What are you trying to achieve ? Is this related to AM437x which doesn't have a USB3 PHY due to the way the HW was wired up ? If so, please mention it. Explain how AM437x HW was wired up, why it lacks a USB3 PHY and why we should support it the way you want. That sort of detail needs to be clear in the commit log, specially considering the peculiar nature of AM43xx which uses a USB3 IP in USB2-only mode, that needs to be documented in the commit log :-) cheers --=20 balbi --pyE8wggRBhVBcj8z Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJS3oh9AAoJEIaOsuA1yqREkYAP/2VZ1tCp2VnzuTB+mNmb5Sm/ Ss4045EJYGv0QhkGmDwnoUEZoZWFpyWo+4h8+J7BpReNuVnF4nqyKX7MvB7Ivd7d a8gAgebL26rpOfBTIlkdYduQxe/EM+95v+E9FQ/M0SKu36UwY93HEF8UnbjXHVsF 2kAYRQMTVoHN6GxP6P4MCNGyojfYMA8uevv/SFr+zTIJTt4/PM17Qsuq1xSMtzRl YPzFDq1tNw+vXeF1IhpSjQ/UhIzOoG1D9Z88/e1CG1eosQQZWDTQDjYYTwhvMIyt PtAHqoEXop0xzQ0Kj6T+7BGwLhu5Zh7tl4vg5veQ7OZSFmpZOmXyNlZ7OeLNRU5h f+3Zj23x3JzDZb1KAxXXc8UYw5ITvF6x5zc82GFCQJgByO6u09vG7cAnKG+GrRiK hQJE5sAxczwXmEfPEOh+PAVU06ie1phF5kjqMdVuLV2uVNftMksaiyarLTixlbKd fryUujqB4oVD3/camDyq7K00zT+nVBE04hHdogtF6uw7GRaiy2eoLlPUSsdZp3V5 Z6IywNb1daTncXcSPTzyZs/osy6hdJuabkuh89WIoBefI23RHnyi4keK+bvUePZs L6d0brIHl1zSOGJpx25SZIEEXeMr4rueXhqVG/CnbuE/zh77Pg4IAcMU/s6IDTzx M8yyG98HI/VHlcUF1O9e =CgjQ -----END PGP SIGNATURE----- --pyE8wggRBhVBcj8z-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/