From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754977AbaIPSaQ (ORCPT ); Tue, 16 Sep 2014 14:30:16 -0400 Received: from arroyo.ext.ti.com ([192.94.94.40]:49362 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754942AbaIPSaL (ORCPT ); Tue, 16 Sep 2014 14:30:11 -0400 Date: Tue, 16 Sep 2014 13:29:21 -0500 From: Felipe Balbi To: Jack Pham CC: Andy Gross , Felipe Balbi , , , , Kishon Vijay Abraham I , Kumar Gala , , , "Ivan T. Ivanov" , Bjorn Andersson Subject: Re: [Patch v9 1/3] usb: dwc3: qcom: Add device tree binding Message-ID: <20140916182920.GF19010@saruman.home> Reply-To: References: <1410550088-8754-1-git-send-email-agross@codeaurora.org> <1410550088-8754-2-git-send-email-agross@codeaurora.org> <20140916181543.GA19101@usblab-sd-06.qualcomm.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="GV0iVqYguTV4Q9ER" Content-Disposition: inline In-Reply-To: <20140916181543.GA19101@usblab-sd-06.qualcomm.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --GV0iVqYguTV4Q9ER Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi, On Tue, Sep 16, 2014 at 11:15:43AM -0700, Jack Pham wrote: > Hi Andy, >=20 > On Fri, Sep 12, 2014 at 02:28:06PM -0500, Andy Gross wrote: > > +Example device nodes: > > + > > + hs_phy: phy@100f8800 { > > + compatible =3D "qcom,dwc3-hs-usb-phy"; > > + reg =3D <0x100f8800 0x30>; >=20 > Just wanted to point out that in our downstream code, the glue > device/driver, i.e. "qcom,dwc3", does claim an entire register region > that encompasses the same registers used by these PHYs. I noticed you're > not adding a reg resource to the glue node below in this patchset. In > order to allow multiple devices to use the overlapping regions, we avoid > calling devm_ioremap_resource() and instead call devm_ioremap_nocache() > directly which bypasses the request_mem_region() call, which I don't > think is an entirely correct thing to do. >=20 > On the other hand I'm trying to think of use cases on our other SOCs > (MSM8974, APQ8084) where the glue actually would need access to the same > or adjacent IO registers that couldn't just be handled directly by these > PHY drivers. Should we accommodate for the potential of overlapping > regions or should we just hold the line here and maybe only expose with > finer granularity the registers that will actually be needed by the PHYs > & glue respectively? I prefer to keep things separated. Glue only needs to access whatever belongs to glue. If a register related to PHY settings, it should be in the PHY address space. cheers --=20 balbi --GV0iVqYguTV4Q9ER Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJUGIGAAAoJEIaOsuA1yqREFMMQAKzDm2voLdtaZavbPW0yaKtn qnkPxiwaxNTqmG7glc/SYXcWftpgS4djTAbk+AVO5X3fqrVo+gI+oyrK8nMOxbgL nTR9hGhQbVf+PB5XHPwpG0/Iw3SgWzyFmyqqHHrh33SSWO6FgMl7uAm8pUUVnZ/G 52LOwCNZKorymcZBvvVgghoqF+3eEI/YrjedaICSmZ5l/kdgvzY22p6G1YBPOyXH y9rfBcyS6Lqx1/IyfBXiOS3METTSz2i6oLW7/GJo2m1/5nn1SqwgVtI7AnZVUoZu +cUMhlluX/D/SxZoXiOglbN3g9yz7MDE75OjN6hvS3SS07sK9qfHRRs5UzlvfIo6 R/hGNu2arkXwCi+P3KZnwvYgm3KarXddLYa1T+Blq9OSDioo+CDzfAv00b2X8P+q N9/MSHGeIFOpAuCoF62buSYvFur19AXu8cVI6tBAquitkeJgWp1CAWdmiE5r/rj4 5T0KScM7vCoi9x6M4VTGgPSHxzK3eZIh7FMru7/4u8we1DozsurbVtmlrvufCDgL Egk/408apu+8Vi4qLDQDDEwfGtr3TKCAaZ8lfBH9MXSWs+nItVTLI8Hayd7Cl3xU BQ99ikq0XeaROrtWuJI7UOzFFM0SIAyOE+bOi+w/9YsQH0cV6ubd33d7GJ+KDIp6 0UfHiOckTFbwzFGkLdIJ =RdvM -----END PGP SIGNATURE----- --GV0iVqYguTV4Q9ER--