From mboxrd@z Thu Jan 1 00:00:00 1970 From: Felipe Balbi Subject: Re: [PATCH v4 2/3] usb: phy: Add Qualcomm SS-USB and HS-USB drivers for DWC3 core Date: Tue, 27 Aug 2013 14:58:59 -0500 Message-ID: <20130827195859.GF3005@radagast> References: <1376992565-22292-3-git-send-email-iivanov@mm-sol.com> <20130820122907.GU26587@radagast> <1377005543.26268.22.camel@iivanov-dev.int.mm-sol.com> <20130820133712.GC26587@radagast> <1377007751.26268.27.camel@iivanov-dev.int.mm-sol.com> <20130820143319.GG26587@radagast> <1377010458.26268.30.camel@iivanov-dev.int.mm-sol.com> <8691FDFE-326E-4198-838A-202D9EC988E1@codeaurora.org> <1377012381.26268.42.camel@iivanov-dev.int.mm-sol.com> Reply-To: Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="8hYiR1SWmJV79WGg" Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-doc-owner@vger.kernel.org To: Paul Zimmerman Cc: "Ivan T. Ivanov" , Kumar Gala , "balbi@ti.com" , "rob.herring@calxeda.com" , "pawel.moll@arm.com" , "mark.rutland@arm.com" , "swarren@wwwdotorg.org" , "ian.campbell@citrix.com" , "rob@landley.net" , "gregkh@linuxfoundation.org" , "grant.likely@linaro.org" , "idos@codeaurora.org" , "mgautam@codeaurora.org" , "devicetree@vger.kernel.org" , "linux-doc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-usb@vger.kernel.org" , "linux-omap@vger.kernel.org" List-Id: devicetree@vger.kernel.org --8hYiR1SWmJV79WGg Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi, On Thu, Aug 22, 2013 at 09:24:49PM +0000, Paul Zimmerman wrote: > > From: Ivan T. Ivanov [mailto:iivanov@mm-sol.com] > > Sent: Tuesday, August 20, 2013 8:26 AM > >=20 > > On Tue, 2013-08-20 at 10:01 -0500, Kumar Gala wrote: > > > On Aug 20, 2013, at 9:54 AM, Ivan T. Ivanov wrote: > > > > > > > > > > > Hi, > > > > > > > > On Tue, 2013-08-20 at 09:33 -0500, Felipe Balbi wrote: > > > >> On Tue, Aug 20, 2013 at 05:09:11PM +0300, Ivan T. Ivanov wrote: > > > >>> > > > >>> On Tue, 2013-08-20 at 08:37 -0500, Felipe Balbi wrote: > > > >>>> > > > >>>> On Tue, Aug 20, 2013 at 04:32:23PM +0300, Ivan T. Ivanov wrote: > > > >>>>> > > > >>>>> I think they are SNPS DesignWare PHY's, additionally > > > >>>>> wrapped with Qualcomm logic. I could substitute "dwc3" > > > >>>>> with just "dw", which will be more correct. > > > >>>> > > > >>>> alright, thank you. Let's add Paul to the loop since he might ha= ve very > > > >>>> good insight in the synopsys PHYs. > > > >>>> > > > >>>> mental note: if any other platform shows up with Synopsys PHY, a= sk them > > > >>>> to use this driver instead :-) > > > >>> > > > >>> I really doubt that this will bi possible. Control of the PHY's is > > > >>> not directly trough ULPI, UTMI or PIPE3 interfaces, but trough > > > >>> QSCRATCH registers, which of course is highly Qualcomm specific. > > > >> > > > >> isn't it a memory mapped IP ? doesn't synopsys provide their own s= et of > > > >> registers ? > > > > > > > > From what I see it is not directly mapped. How QSCRATCH write and > > > > reads transactions are translated to DW IP is unclear to me. > > > > > > > > > I think the question is how does SW access them? > >=20 > > "USB QSCRATCH Hardware registers" don't ask me what is this :-) > > or like Pawel says: "it depends on the SOC" . >=20 > To answer the question "doesn't synopsys provide their own set of > registers", we provide registers in our USB cores to access the PHYs > through I2C, ULPI/UTMI, or PIPE3 interfaces. But if someone wants to use > our PHY with some other controller that doesn't provide that, then they > may need to implement their own register set, as Qualcomm has apparently > done. thanks for clarifying. that pretty much hinders writing any sort of generic drivers for Synopsys' PHYs though :-s But I guess that's alright. --=20 balbi --8hYiR1SWmJV79WGg Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJSHQUDAAoJEIaOsuA1yqREE5AP/2ZZ5zmei7G9/mOyYAwyr3/z 79+Q+X/YxO2IKZSGZvH7fEyIbIsVBGq1BxFJTOyhkg6EyHkZixZeUotzMcMtcNB9 OsSkZTlVNLGa737/U0FAHwG9xLXrL3pHKiZepuZ3V2ch/2MlCY1IQn2BmBjfsrC+ PNHEjYyn1266O6r2JVJuiHv3sWyUI1cIbDn8d8jJG2pvbAAuEhmkgWMHZkSFvtco MrORQpW4beCZAYPtdsukl4jllXIa1Uu+J0+ff5ViHzTZxK4xGpYIQU3smLkU/F52 hWdqr/gfsWSQa3/sHn6zJEaoQW/HlySAOaD6SzHCoLFUoemDqYkg0w0HPBRS8+lP g4ON6lvPywt0xOTzrgbGRp+OORnVwQOuKnfAI16aio/NZPsuIJKP8ECrVYjVno1b kkzg7x6i6ziSZ3iYimuN3w6hEG+RoK9qe/eCgmi8SuenpifOtdhjl7QexgAx5gC6 j4Ux4/bGtg0oawzqfAuh87aC1XRn1EZjEHQWo8VH8iVbIWbLIH5NcAaq5U6EqraF 4YLMOFGIjMgp8y+MAaIilZqiyBrRz24p+om1riZQOWLlYZZjjJPunhWI5BmA71mT 3LMdpnJLLYceHQjgBPm2WSyvwFqMSiNzicmPpgY8312/utPUX5KkBv3J1/nIeFge 39L0sMFx6xf3DhMmYM5F =OD97 -----END PGP SIGNATURE----- --8hYiR1SWmJV79WGg--