Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754130AbaKRMUW (ORCPT ); Tue, 18 Nov 2014 07:20:22 -0500 Received: from mail-qg0-f46.google.com ([209.85.192.46]:44568 "EHLO mail-qg0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753020AbaKRMUU (ORCPT ); Tue, 18 Nov 2014 07:20:20 -0500 MIME-Version: 1.0 In-Reply-To: <546A1F64.7000209@cogentembedded.com> References: <1414761989-21088-1-git-send-email-gautam.vivek@samsung.com> <1414761989-21088-2-git-send-email-gautam.vivek@samsung.com> <545393CE.8070102@cogentembedded.com> <546A1F64.7000209@cogentembedded.com> Date: Tue, 18 Nov 2014 17:50:19 +0530 Message-ID: Subject: Re: [PATCH v7 1/2] usb: host: xhci-plat: Get PHYs for xhci's hcds From: Vivek Gautam To: Sergei Shtylyov Cc: Vivek Gautam , Linux USB Mailing List , "linux-samsung-soc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Greg KH , kishon , Felipe Balbi , Alan Stern , Kukjin Kim , Heikki Krogerus , Mathias Nyman , Julius Werner , Jingoo Han Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 17, 2014 at 9:46 PM, Sergei Shtylyov wrote: > Hello. > > On 11/17/2014 9:36 AM, Vivek Gautam wrote: > >>>> The host controller by itself may sometimes need to handle PHY >>>> and re-initialize it to re-configure some of the PHY parameters >>>> to get full support out of the PHY controller. >>>> Therefore, facilitate getting the two possible PHYs, viz. >>>> USB 2.0 type (UTMI+) and USB 3.0 type (PIPE3), and initialize them. > > >>>> Signed-off-by: Vivek Gautam >>>> --- >>>> drivers/usb/host/xhci-plat.c | 74 >>>> ++++++++++++++++++++++++++++++++++++++++++ >>>> 1 file changed, 74 insertions(+) > > >>>> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c >>>> index 3d78b0c..5207d5b 100644 >>>> --- a/drivers/usb/host/xhci-plat.c >>>> +++ b/drivers/usb/host/xhci-plat.c > > [...] >>>> >>>> @@ -204,6 +271,8 @@ static int xhci_plat_suspend(struct device *dev) >>>> struct usb_hcd *hcd = dev_get_drvdata(dev); >>>> struct xhci_hcd *xhci = hcd_to_xhci(hcd); >>>> >>>> + phy_exit(hcd->phy); > > >>> Hm, in the suspend() method? > > >> phy_exit() should eventually be suspending the PHY and put it to >> low power state. > > > I thought it's a role that the power_off() mothod should play, > considering that the power_on() method gets called after the init() > method.... phy_power_off() should be cutting the clocks and power from PHY completely, no ? In that case one may not be able to wakeup the system from USB. So phy_exit() gets the responsibility to put the PHY into low power state. Ccing Kishon also to get his opinion on actual role of the two callbacks - phy_init/exit() and phy_power_on/off(). > >> phy_init() in resume() will then take up the task of activating the >> PHY again. > > >> phy_power_on() and phy_power_off() are called at xhci_probe() and remove() >> time. > > > Of course. > >> Does this makes sense ? > > > Not much, really. > > WBR, Sergei > -- Best Regards Vivek Gautam Samsung R&D Institute, Bangalore India -- 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/