Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752864Ab3ILLFi (ORCPT ); Thu, 12 Sep 2013 07:05:38 -0400 Received: from bear.ext.ti.com ([192.94.94.41]:51424 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751533Ab3ILLFf (ORCPT ); Thu, 12 Sep 2013 07:05:35 -0400 Message-ID: <52319FC4.8040703@ti.com> Date: Thu, 12 Sep 2013 14:04:36 +0300 From: Roger Quadros User-Agent: Mozilla/5.0 (X11; Linux i686; rv:16.0) Gecko/20121011 Thunderbird/16.0.1 MIME-Version: 1.0 To: Vivek Gautam CC: Kishon Vijay Abraham I , Felipe Balbi , Benoit Cousson , Tony Lindgren , Rob Herring , Pawel Moll , Mark Rutland , Russell King - ARM Linux , Grant Likely , Sylwester Nawrocki , Kumar Gala , Stephen Warren , Ian Campbell , Rob Landley , , Greg KH , , , "devicetree@vger.kernel.org" , Linux USB Mailing List , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 1/7] usb: dwc3: get "usb_phy" only if the platform indicates the presence of PHY References: <1378136591-7463-1-git-send-email-kishon@ti.com> <1378136591-7463-2-git-send-email-kishon@ti.com> <52319912.8030203@ti.com> In-Reply-To: Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3189 Lines: 73 Hi, On 09/12/2013 01:47 PM, Vivek Gautam wrote: > On Thu, Sep 12, 2013 at 4:06 PM, Roger Quadros wrote: >> Hi Kishon, >> >> On 09/02/2013 06:43 PM, Kishon Vijay Abraham I wrote: >>> There can be systems which does not have a external usb_phy, so get >>> usb_phy only if usb-phy property is added in the case of dt boot or if >>> platform_data indicates the presence of PHY. Also remove checking if >>> return value is -ENXIO since it's now changed to always enable usb_phy layer. >>> >>> Signed-off-by: Kishon Vijay Abraham I >>> --- >>> drivers/usb/dwc3/Kconfig | 1 + >>> drivers/usb/dwc3/core.c | 60 +++++++++++++++++--------------------- >>> drivers/usb/dwc3/platform_data.h | 1 + >>> 3 files changed, 28 insertions(+), 34 deletions(-) >>> >>> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig >>> index f969ea2..cfc16dd 100644 >>> --- a/drivers/usb/dwc3/Kconfig >>> +++ b/drivers/usb/dwc3/Kconfig >>> @@ -2,6 +2,7 @@ config USB_DWC3 >>> tristate "DesignWare USB3 DRD Core Support" >>> depends on (USB || USB_GADGET) && GENERIC_HARDIRQS && HAS_DMA >>> depends on EXTCON >>> + select USB_PHY >>> select USB_XHCI_PLATFORM if USB_SUPPORT && USB_XHCI_HCD >>> help >>> Say Y or M here if your system has a Dual Role SuperSpeed >>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c >>> index 474162e..428c29e 100644 >>> --- a/drivers/usb/dwc3/core.c >>> +++ b/drivers/usb/dwc3/core.c >>> @@ -387,16 +387,38 @@ static int dwc3_probe(struct platform_device *pdev) >>> if (node) { >>> dwc->maximum_speed = of_usb_get_maximum_speed(node); >>> >>> - dwc->usb2_phy = devm_usb_get_phy_by_phandle(dev, "usb-phy", 0); >>> - dwc->usb3_phy = devm_usb_get_phy_by_phandle(dev, "usb-phy", 1); >>> + if (of_property_read_bool(node, "usb-phy")) { >>> + dwc->usb2_phy = devm_usb_get_phy_by_phandle(dev, >>> + "usb-phy", 0); >>> + if (IS_ERR(dwc->usb2_phy)) >>> + return PTR_ERR(dwc->usb2_phy); >>> + dwc->usb3_phy = devm_usb_get_phy_by_phandle(dev, >>> + "usb-phy", 1); >>> + if (IS_ERR(dwc->usb3_phy)) >>> + return PTR_ERR(dwc->usb3_phy); >> >> Some DWC3 instances use only usb2_phy. e.g. on DRA7 the 2nd dwc3 instance doesn't use usb3_phy. >> This needs to be a valid case and driver shouldn't error out. > > So, i think adding flexibility to DWC3 to have either > usb2-phy/usb3-phy or both of them seems to be valid point. > Any suggestions ? > For high speed operation we need only usb2_phy but for super speed we need both usb2_phy and usb3_phy. Why would a dwc3 controller use only usb3_phy? A USB3.0 interface has to be compatible with USB2.0 as well, no? cheers, -roger -- 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/