From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1426856AbcBRSb1 (ORCPT ); Thu, 18 Feb 2016 13:31:27 -0500 Received: from mail-lf0-f54.google.com ([209.85.215.54]:33628 "EHLO mail-lf0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1426516AbcBRSbZ (ORCPT ); Thu, 18 Feb 2016 13:31:25 -0500 Subject: Re: [RFC v5 07/15] usb: ehci: add vbus-gpio parameter To: Antony Pavlov , Alan Stern , Marek Vasut References: <1455005641-7079-8-git-send-email-antonynpavlov@gmail.com> <20160218210652.68ae464eed8ddbffd33e7a02@gmail.com> Cc: linux-mips@linux-mips.org, Wills Wang , Daniel Schwierzeck , Alban Bedel , Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org From: Sergei Shtylyov Organization: Cogent Embedded Message-ID: <56C60DF8.1060809@cogentembedded.com> Date: Thu, 18 Feb 2016 21:31:20 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.0 MIME-Version: 1.0 In-Reply-To: <20160218210652.68ae464eed8ddbffd33e7a02@gmail.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/18/2016 09:06 PM, Antony Pavlov wrote: >>> This patch retrieves and configures the vbus control gpio via >>> the device tree. >>> >>> This patch is based on a ehci-s5p.c commit fd81d59c90d38661 >>> ("USB: ehci-s5p: Add vbus setup function to the s5p ehci glue layer"). >>> >>> Signed-off-by: Antony Pavlov >>> Cc: Alan Stern >>> Cc: Greg Kroah-Hartman >>> Cc: linux-usb@vger.kernel.org >>> Cc: linux-kernel@vger.kernel.org >>> --- >>> drivers/usb/host/ehci-platform.c | 22 ++++++++++++++++++++++ >>> 1 file changed, 22 insertions(+) >>> >>> diff --git a/drivers/usb/host/ehci-platform.c b/drivers/usb/host/ehci-platform.c >>> index bd7082f2..0d95ced 100644 >>> --- a/drivers/usb/host/ehci-platform.c >>> +++ b/drivers/usb/host/ehci-platform.c >>> @@ -28,6 +28,7 @@ >>> #include >>> #include >>> #include >>> +#include >>> #include >>> #include >>> #include >>> @@ -142,6 +143,25 @@ static struct usb_ehci_pdata ehci_platform_defaults = { >>> .power_off = ehci_platform_power_off, >>> }; >>> >>> +static void setup_vbus_gpio(struct device *dev) >>> +{ >>> + int err; >>> + int gpio; >>> + >>> + if (!dev->of_node) >>> + return; >>> + >>> + gpio = of_get_named_gpio(dev->of_node, "vbus-gpio", 0); >>> + if (!gpio_is_valid(gpio)) >>> + return; >>> + >>> + err = devm_gpio_request_one(dev, gpio, >>> + GPIOF_OUT_INIT_HIGH | GPIOF_EXPORT_DIR_FIXED, >>> + "ehci_vbus_gpio"); >>> + if (err) >>> + dev_err(dev, "can't request ehci vbus gpio %d", gpio); >> >> >> I don't understand this. If you get an error here, what's the point of >> allowing the probe to continue? Shouldn't you return an error code so >> the probe will fail? > > Please ignore the 'usb: ehci: add vbus-gpio parameter' patch! > > In the new AR9331 patchseries I use chipidea USB driver (thanks to Marek for the suggestion) > in the AR9331 dtsi-file: > > usb: usb@1b000100 { > compatible = "chipidea,usb2"; > reg = <0x1b000000 0x200>; > > interrupt-parent = <&cpuintc>; > interrupts = <3>; > resets = <&rst 5>; > > phy-names = "usb-phy"; > phys = <&usb_phy>; > > status = "disabled"; > }; > > > so I use regulator in the TL-MR3020 board dts file: > > reg_usb_vbus: reg_usb_vbus { > compatible = "regulator-fixed"; > regulator-name = "usb_vbus"; > regulator-min-microvolt = <5000000>; Not 0? > regulator-max-microvolt = <5000000>; > gpio = <&gpio 8 GPIO_ACTIVE_HIGH>; Where's the switch if both voltages are equal? > enable-active-high; > }; > > &usb { > dr_mode = "host"; > vbus-supply = <®_usb_vbus>; > status = "okay"; > }; > > As a result there is no need in adding vbus-gpio parameter to ehci anymore! [...] MBR, Sergei