From: Arnd Bergmann <arnd@arndb.de>
To: Adrien =?utf-8?q?Verg=C3=A9?= <adrienverge@gmail.com>
Subject: Re: [PATCH] ARM: OMAP4: USB_EHCI_HCD needs USB_PHY and NOP_USB_XCEIV
Date: Mon, 27 May 2013 20:23:12 +0200
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Cc: "Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
        Alan Stern <stern@rowland.harvard.edu>,
        Florian Fainelli <florian@openwrt.org>,
        Manjunath Goudar <manjunath.goudar@linaro.org>,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
        Yannick Brosseau <yannick.brosseau@gmail.com>, rogerq@ti.com
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On Saturday 25 May 2013, Adrien Vergé wrote:
> On OMAP4 platforms, EHCI HCD needs the physical layer signalling
> activated, along with the NOP USB Transceiver driver. Otherwise, the
> kernel boots without registering any USB device.

This does not actually sound like a critical error: If a user forgets
to enable a driver, that driver will not be loaded. Of course the
kernel should not just crash when a non-essential driver is missing,
and it should not fail to build, but your description sounds harmless.

Am I missing something?

> This patch applies to Linux 3.10-rc2.
> 
> Signed-off-by: Adrien Vergé <adrienverge@gmail.com>
> ---
> diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
> index de94f26..47959d7 100644
> --- a/drivers/usb/host/Kconfig
> +++ b/drivers/usb/host/Kconfig
> @@ -44,6 +44,8 @@ endif # USB_XHCI_HCD
>  config USB_EHCI_HCD
>         tristate "EHCI HCD (USB 2.0) support"

This is the wrong place: it should be in USB_EHCI_HCD_OMAP
if any.

>         depends on USB_ARCH_HAS_EHCI
> +       select USB_PHY if ARCH_OMAP4
> +       select NOP_USB_XCEIV if ARCH_OMAP4
>         ---help---
>           The Enhanced Host Controller Interface (EHCI) is standard for USB 2.0
>           "high speed" (480 Mbit/sec, 60 Mbyte/sec) host controller hardware.

'select'ing USB_PHY sounds wrong too, I think you mean 'depends on'.

Also note that Roger Quadros has just removed the 'select NOP_USB_XCEIV'
there, I think you should coordinate with him.

	Arnd
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