From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752302AbaCFIw1 (ORCPT ); Thu, 6 Mar 2014 03:52:27 -0500 Received: from mailout4.samsung.com ([203.254.224.34]:55481 "EHLO mailout4.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752211AbaCFIwX (ORCPT ); Thu, 6 Mar 2014 03:52:23 -0500 X-AuditID: cbfee68e-b7f566d000002344-aa-5318373fee2a From: Anton Tikhomirov To: "'Kishon Vijay Abraham I'" , "'Kamil Debski'" , linux-kernel@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-usb@vger.kernel.org, devicetree@vger.kernel.org Cc: kyungmin.park@samsung.com, t.figa@samsung.com, s.nawrocki@samsung.com, m.szyprowski@samsung.com, gautam.vivek@samsung.com, mat.krawczuk@gmail.com, yulgon.kim@samsung.com, p.paneri@samsung.com, jg1.han@samsung.com, galak@codeaurora.org, matt.porter@linaro.org, tjakobi@math.uni-bielefeld.de, stern@rowland.harvard.edu, sander@humilis.net References: <1394033288-5551-1-git-send-email-k.debski@samsung.com> <1394033288-5551-4-git-send-email-k.debski@samsung.com> <005c01cf3915$c53476c0$4f9d6440$%tikhomirov@samsung.com> <53183220.3040606@ti.com> In-reply-to: <53183220.3040606@ti.com> Subject: RE: [PATCH v9 3/4] phy: Add new Exynos USB 2.0 PHY driver Date: Thu, 06 Mar 2014 17:52:15 +0900 Message-id: <006201cf3919$5f760750$1e6215f0$%tikhomirov@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=Windows-1252 Content-transfer-encoding: 7bit X-Mailer: Microsoft Office Outlook 12.0 Thread-index: Ac85FnrWZKuyndfUQzSEi6dqu4vhFgAAiZLQ Content-language: en-us X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrOKsWRmVeSWpSXmKPExsVy+t8zA117c4lggwuzrCzmHznHatH/ZiGr RduVg+wWlxdeYrX48foCm8WFpz1sFmeb3gDFds1hs5hxfh+TxaJlrcwWa4/cZbc423+bzWJi 0zR2i/NbOpksDr9pZ7VYcW83u8WE30C962e8ZrFoW/2B1aLj7EF2BxGPy329TB47Z91l9/j0 djGzx51re9g8/h1j95h99wejR9+WVYwex29sZ/L4vEkugDOKyyYlNSezLLVI3y6BK+PdtDmM BUdEKiatvcHYwDhboIuRk0NCwETi75tuNghbTOLCvfVANheHkMAyRome79PYYYoWnWplgkgs YpRYtv49K0hCSOAfo8Sv5hwQm03ASOLlwY3MIEUiAhcZJaZO38sI4jAL3GGS+DJ/H1T7FUaJ nW/OA2U4ODgF1CS29yiDdAsLOElceN7IBGKzCKhKzGj5DLaBV8BFoutML5QtKPFj8j0WEJtZ QE/i45/bjBC2vMTmNW+ZQUZKCKhLPPqrCxIWATpo1ck1bBAl4hKTHjxkBzlBQuANh8TETxNY IHYJSHybfIgFoldWYtMBZoiPJSUOrrjBMoFRYhaSzbOQbJ6FZPMsJCsWMLKsYhRNLUguKE5K LzLSK07MLS7NS9dLzs/dxAhJNH07GG8esD7EmAy0fiKzlGhyPjBR5ZXEGxqbGVmYmpgaG5lb mpEmrCTOu+hhUpCQQHpiSWp2ampBalF8UWlOavEhRiYOTqkGRv2Z1h6X+RU/T/1/5NL/eu+L EfvSRa64HN8ksP9DcOCXSW/qVyauU9y/xkWMIaI2+eDt5Q0/pE4c3CCo9KP7gOS+i40Bh705 7KwuHxNN2nyRd82ZK2FOXNK5vIyqa9jmT/dOyhA69/9hazrndgeRtDUJV1laFCO+vr9qq1D9 tHuyZ/zW6TP8mZVYijMSDbWYi4oTAcUNHZtKAwAA X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprCJsWRmVeSWpSXmKPExsVy+t9jAV17c4lgg7b3xhbzj5xjteh/s5DV ou3KQXaLywsvsVr8eH2BzeLC0x42i7NNb4Biu+awWcw4v4/JYtGyVmaLtUfusluc7b/NZjGx aRq7xfktnUwWh9+0s1qsuLeb3WLCb6De9TNes1i0rf7AatFx9iC7g4jH5b5eJo+ds+6ye3x6 u5jZ4861PWwe/46xe8y++4PRo2/LKkaP4ze2M3l83iQXwBnVwGiTkZqYklqkkJqXnJ+SmZdu q+QdHO8cb2pmYKhraGlhrqSQl5ibaqvk4hOg65aZA/SbkkJZYk4pUCggsbhYSd8O04TQEDdd C5jGCF3fkCC4HiMDNJCwjjHj3bQ5jAVHRComrb3B2MA4W6CLkZNDQsBEYtGpViYIW0ziwr31 bF2MXBxCAosYJZatf88KkhAS+Mco8as5B8RmEzCSeHlwIzNIkYjARUaJqdP3MoI4zAJ3mCS+ zN/HBNF+hVFi55vzQBkODk4BNYntPcog3cICThIXnjeCrWMRUJWY0fIZbAOvgItE15leKFtQ 4sfkeywgNrOAnsTHP7cZIWx5ic1r3jKDjJQQUJd49FcXJCwCdNCqk2vYIErEJSY9eMg+gVFo FpJJs5BMmoVk0iwkLQsYWVYxiqYWJBcUJ6XnGuoVJ+YWl+al6yXn525iBKexZ1I7GFc2WBxi FOBgVOLh3eAnHizEmlhWXJl7iFGCg1lJhHeLoUSwEG9KYmVValF+fFFpTmrxIcZkoEcnMkuJ JucDU2xeSbyhsYmZkaWRmYWRibk5acJK4rwHWq0DhQTSE0tSs1NTC1KLYLYwcXBKNTDun8TX el3CN5pRbk5V4Nqdn+vul9/p+efxZtq+/KbXt2dx5WkcTLpXy/U28p7P71MFDoJbOh1kdXS3 1X5pv+UmfYynO/qF+KVHUis/Jqo6l0dm1097fuVl7ZpvaReK2WV1vNbMs9xt837O5ardd27N /j/RtbfiQNaj0MkTA04tdi2tZHOYe3+aEktxRqKhFnNRcSIAgHyf6KcDAAA= DLP-Filter: Pass X-MTR: 20000000000000000@CPGS X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, > Subject: Re: [PATCH v9 3/4] phy: Add new Exynos USB 2.0 PHY driver > > > > On Thursday 06 March 2014 01:56 PM, Anton Tikhomirov wrote: > > Hi Kamil, > > > > ... > > > >> +| 3. Supporting SoCs > >> ++-------------------- > >> + > >> +To support a new SoC a new file should be added to the drivers/phy > >> +directory. Each SoC's configuration is stored in an instance of the > >> +struct samsung_usb2_phy_config. > >> + > >> +struct samsung_usb2_phy_config { > >> + const struct samsung_usb2_common_phy *phys; > >> + unsigned int num_phys; > >> + bool has_mode_switch; > > > > You missed rate_to_clk here. > > > >> +}; > >> + > > > > ... > > > >> diff --git a/drivers/phy/phy-samsung-usb2.c b/drivers/phy/phy- > samsung- > >> usb2.c > >> new file mode 100644 > >> index 0000000..c3b7719 > >> --- /dev/null > >> +++ b/drivers/phy/phy-samsung-usb2.c > >> @@ -0,0 +1,222 @@ > >> +/* > >> + * Samsung SoC USB 1.1/2.0 PHY driver > >> + * > >> + * Copyright (C) 2013 Samsung Electronics Co., Ltd. > >> + * Author: Kamil Debski > >> + * > >> + * This program is free software; you can redistribute it and/or > >> modify > >> + * it under the terms of the GNU General Public License version 2 > as > >> + * published by the Free Software Foundation. > >> + */ > >> + > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include "phy-samsung-usb2.h" > >> + > >> +static int samsung_usb2_phy_power_on(struct phy *phy) > >> +{ > >> + struct samsung_usb2_phy_instance *inst = phy_get_drvdata(phy); > >> + struct samsung_usb2_phy_driver *drv = inst->drv; > >> + int ret; > >> + > >> + dev_dbg(drv->dev, "Request to power_on \"%s\" usb phy\n", > >> + inst->cfg->label); > >> + ret = clk_prepare_enable(drv->clk); > > > > clk_prepare_enable() can sleep, and therefore doesn't allow > > samusng_usb2_phy_power_on() to be used in atomic context > > (e.g. inside spin_lock-ed area), what sometimes may be desirable. > > What about to prepare clock in probe, and just enable it here > > (note: clk_enable() doesn't sleep). > > The PHY power-on callback is anyway called with mutex held, so I guess > it's fine to have clk_prepare_enable() here. If we rely totally on generic PHY functions such as phy_power_on() and friends, why do we need to use locking in callbacks at all. > > Thanks > Kishon