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Sender: Guenter Roeck <groeck7@gmail.com>
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Date: Mon, 25 Mar 2024 09:41:36 -0700
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Subject: Re: [PATCH v3 3/3] media: uvcvideo: Exit early if there is not
 int_urb
Content-Language: en-US
To: Ricardo Ribalda <ribalda@chromium.org>,
 Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Max Staudt <mstaudt@chromium.org>, Tomasz Figa <tfiga@chromium.org>,
 Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
 Alan Stern <stern@rowland.harvard.edu>,
 Hans Verkuil <hverkuil-cisco@xs4all.nl>, linux-media@vger.kernel.org,
 linux-kernel@vger.kernel.org, Sean Paul <seanpaul@chromium.org>,
 Sakari Ailus <sakari.ailus@linux.intel.com>
References: <20240325-guenter-mini-v3-0-c4bc61d84e03@chromium.org>
 <20240325-guenter-mini-v3-3-c4bc61d84e03@chromium.org>
From: Guenter Roeck <linux@roeck-us.net>
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In-Reply-To: <20240325-guenter-mini-v3-3-c4bc61d84e03@chromium.org>
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On 3/25/24 09:31, Ricardo Ribalda wrote:
> If there is no in_urb there is no need to do a clean stop.
> 
Nit: int_urb

Guenter

> Also we avoid calling usb_kill_urb(NULL). It is properly handled by the
> usb framework, but it is not polite.
> 
> Now that we are at it, fix the code style in uvc_status_start() for
> consistency.
> 
> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
> ---
>   drivers/media/usb/uvc/uvc_status.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/usb/uvc/uvc_status.c b/drivers/media/usb/uvc/uvc_status.c
> index ff66482346dde..f644ac7e67427 100644
> --- a/drivers/media/usb/uvc/uvc_status.c
> +++ b/drivers/media/usb/uvc/uvc_status.c
> @@ -308,7 +308,7 @@ static int _uvc_status_start(struct uvc_device *dev, gfp_t flags)
>   {
>   	lockdep_assert_held(&dev->status_lock);
>   
> -	if (dev->int_urb == NULL)
> +	if (!dev->int_urb)
>   		return 0;
>   
>   	return usb_submit_urb(dev->int_urb, flags);
> @@ -320,6 +320,9 @@ static void _uvc_status_stop(struct uvc_device *dev)
>   
>   	lockdep_assert_held(&dev->status_lock);
>   
> +	if (!dev->int_urb)
> +		return;
> +
>   	/*
>   	 * Prevent the asynchronous control handler from requeing the URB. The
>   	 * barrier is needed so the flush_status change is visible to other
>