Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752010Ab3HUNH2 (ORCPT ); Wed, 21 Aug 2013 09:07:28 -0400 Received: from ns.mm-sol.com ([212.124.72.66]:47784 "EHLO extserv.mm-sol.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751528Ab3HUNHY (ORCPT ); Wed, 21 Aug 2013 09:07:24 -0400 Message-ID: <1377090364.15070.13.camel@iivanov-dev.int.mm-sol.com> Subject: Re: [PATCH v4 2/3] usb: phy: Add Qualcomm SS-USB and HS-USB drivers for DWC3 core From: "Ivan T. Ivanov" To: Pawel Moll Cc: Kumar Gala , "balbi@ti.com" , "rob.herring@calxeda.com" , Mark Rutland , "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" , "linux-arm-msm@vger.kernel.org" , Paul Zimmerman Date: Wed, 21 Aug 2013 16:06:04 +0300 In-Reply-To: <1377018092.31445.42.camel@hornet> References: <1376992565-22292-1-git-send-email-iivanov@mm-sol.com> <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> <1377011163.31445.30.camel@hornet> <1377018092.31445.42.camel@hornet> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 8bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3533 Lines: 83 On Tue, 2013-08-20 at 18:01 +0100, Pawel Moll wrote: > On Tue, 2013-08-20 at 16:06 +0100, Pawel Moll wrote: > > On Tue, 2013-08-20 at 16:01 +0100, 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: > > > >>> Hi, > > > >>> > > > >>> On Tue, 2013-08-20 at 08:37 -0500, Felipe Balbi wrote: > > > >>>> Hi, > > > >>>> > > > >>>> On Tue, Aug 20, 2013 at 04:32:23PM +0300, Ivan T. Ivanov wrote: > > > >>>>>> On Tue, Aug 20, 2013 at 12:56:04PM +0300, Ivan T. Ivanov wrote: > > > >>>>>>> From: "Ivan T. Ivanov" > > > >>>>>>> > > > >>>>>>> These drivers handles control and configuration of the HS > > > >>>>>>> and SS USB PHY transceivers. They are part of the driver > > > >>>>>>> which manage Synopsys DesignWare USB3 controller stack > > > >>>>>>> inside Qualcomm SoC's. > > > >>>>>>> > > > >>>>>>> Signed-off-by: Ivan T. Ivanov > > > >>>>>>> --- > > > >>>>>>> drivers/usb/phy/Kconfig | 11 ++ > > > >>>>>>> drivers/usb/phy/Makefile | 2 + > > > >>>>>>> drivers/usb/phy/phy-msm-dwc3-hs.c | 327 ++++++++++++++++++++++++++++++++ > > > >>>>>>> drivers/usb/phy/phy-msm-dwc3-ss.c | 374 +++++++++++++++++++++++++++++++++++++ > > > >>>>>> > > > >>>>>> please rename these PHY drivers, they have nothing to do with DWC3. PHYs > > > >>>>>> don't care about the USB controller. > > > >>>>> > > > >>>>> 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 have very > > > >>>> good insight in the synopsys PHYs. > > > >>>> > > > >>>> mental note: if any other platform shows up with Synopsys PHY, ask 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 set 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? > > > > I afraid the answer may be: "it depends on the SOC". In my past I had to > > initialize a (SATA) PHY by implementing a software JTAG state machine, > > as the PHY's registers were not memory mapped *at all*. And the IP > > itself came from Synopsys, Cadence or yet another EDA company... > > Having said all that... If the PHY's spec at least defined layout of the > registers in question and driver was using regmap API to talk to the > device (initially regmap-mmio), it has some chances to become universal. > The SOCs designed like "my" one would have to provide a custom regmap > implementation. Sound reasonable. Unfortunately I don't have PHY's IP spec. Regards, Ivan > > Paweł > -- 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/