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Message-ID: <64825178-2310-8c8a-2ed9-4ae14a46915e@collabora.com>
Date:   Thu, 25 May 2023 10:07:52 +0200
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Subject: Re: [PATCH v2] usb: common: usb-conn-gpio: Set last role to unknown
 before initial detection
To:     Prashanth K <quic_prashk@quicinc.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Matthias Brugger <matthias.bgg@gmail.com>
Cc:     linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
References: <1684936207-23529-1-git-send-email-quic_prashk@quicinc.com>
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From:   AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
In-Reply-To: <1684936207-23529-1-git-send-email-quic_prashk@quicinc.com>
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Il 24/05/23 15:50, Prashanth K ha scritto:
> Currently if we bootup a device without cable connected, then
> usb-conn-gpio won't call set_role() since last_role is same as
> current role. This happens because during probe last_role gets
> initialized to zero.
> 
> To avoid this, added a new constant in enum usb_role, last_role
> is set to USB_ROLE_UNKNOWN before performing initial detection.
> 
> Fixes: 4602f3bff266 ("usb: common: add USB GPIO based connection detection driver")
> Signed-off-by: Prashanth K <quic_prashk@quicinc.com>

There's an issue with drivers/usb/cdns3/core.c as pointed out by the
test robot; the solution is to handle `default` in the switch, I'd say
that it would be safe to handle it as

	default:
		break;

after solving that:

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

> ---
> v2: Added USB_ROLE_UNKNWON to enum usb_role
> 
>   drivers/usb/common/usb-conn-gpio.c | 3 +++
>   include/linux/usb/role.h           | 1 +
>   2 files changed, 4 insertions(+)
> 
> diff --git a/drivers/usb/common/usb-conn-gpio.c b/drivers/usb/common/usb-conn-gpio.c
> index e20874c..30bdb81 100644
> --- a/drivers/usb/common/usb-conn-gpio.c
> +++ b/drivers/usb/common/usb-conn-gpio.c
> @@ -257,6 +257,9 @@ static int usb_conn_probe(struct platform_device *pdev)
>   	platform_set_drvdata(pdev, info);
>   	device_set_wakeup_capable(&pdev->dev, true);
>   
> +	/* Set last role to unknown before performing the initial detection */
> +	info->last_role = USB_ROLE_UNKNOWN;
> +
>   	/* Perform initial detection */
>   	usb_conn_queue_dwork(info, 0);
>   
> diff --git a/include/linux/usb/role.h b/include/linux/usb/role.h
> index b5deafd..221d462 100644
> --- a/include/linux/usb/role.h
> +++ b/include/linux/usb/role.h
> @@ -8,6 +8,7 @@
>   struct usb_role_switch;
>   
>   enum usb_role {
> +	USB_ROLE_UNKNOWN = -1,
>   	USB_ROLE_NONE,
>   	USB_ROLE_HOST,
>   	USB_ROLE_DEVICE,