From nobody Fri Dec 19 19:19:15 2025 Received: from m16.mail.163.com (m16.mail.163.com [220.197.31.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E46363C17 for ; Thu, 8 May 2025 01:56:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.2 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746669406; cv=none; b=B9uTy18a0xEJEFCVD5WJbJ22xAT/4G4ECsmJr+VY2a1OJ846JOGRagRlLq6RkEvnD1WcrsLCEDpGCRL75eN5v6qANKEG43DJKBpTqeaO8YLUX1NQ54toiOIUdkHBu3Wla/rRRsgun1ZUBI7c5q3Jmkyf3ppPEhWT0kVT2YpUMic= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746669406; c=relaxed/simple; bh=WBXa/Ye/zLlnzrQ4CHT8UO61bn51am/3m3eV3ceaDJA=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=R+aq3fFIMTp0q8xHfYJEadaDLrwoUYgNTJ7CfQ3t45en7eW0J7WnJTiiBU3aaGWZXhk8qldf1YIy8MLmpjQ12NsE6YKdZloV2enfVqT3vlE0twBPixYY8DMzSQapFtbNJottBAB26HMZgaThxeDjGf+jriGK3JFEs6D1LvJp8nM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=RQHJWjSc; arc=none smtp.client-ip=220.197.31.2 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="RQHJWjSc" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id:MIME-Version; bh=shiMd LT84fFwKU1ne2krV4nFPcgrNqkX8Bo7YL0kJcs=; b=RQHJWjScre8Na6h8csRMR b2drtxp0YiU/MzljqN+xGYl3Gr+BskYH/ERb0X1SLtoPKVR1OjJmywSTNBObubrp 2YjbOaJDeBj9TXakjA7UX9bx3nXnf/c0J8ibc8z6gk9Yv+inBsSbBQdpD/BAPuGt kD2FXq1eVH/P1xxbS7EEE0= Received: from localhost.localdomain (unknown []) by gzsmtp3 (Coremail) with SMTP id PigvCgAXCpUmDxxolLbgCA--.57679S2; Thu, 08 May 2025 09:55:52 +0800 (CST) From: chenchangcheng To: laurent.pinchart@ideasonboard.com, ribalda@chromium.org Cc: hdegoede@redhat.com, mchehab@kernel.org, linux-kernel@vger.kernel.org, chenchangcheng , kernel test robot Subject: [PATCH v8] media: uvcvideo: Fix bandwidth issue for Alcor camera. Date: Thu, 8 May 2025 09:55:42 +0800 Message-Id: <20250508015542.148301-1-ccc194101@163.com> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: PigvCgAXCpUmDxxolLbgCA--.57679S2 X-Coremail-Antispam: 1Uf129KBjvJXoW7ZFWDKry5WFWfKF1xAr4UCFg_yoW8Ar1Dpa 1ruayFyryUJrWFganrJa1Fga15Janaka1fKFW3u34kZr45JryxZFy3K340q34qy3Z3C343 tryqqr9F93yvvr7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07joZXOUUUUU= X-CM-SenderInfo: 5fffimiurqiqqrwthudrp/1tbiTQNG3mgbTL69awABsA Content-Type: text/plain; charset="utf-8" From: chenchangcheng Some broken device return wrong dwMaxPayloadTransferSize fields as follows: [ 218.632537] [pid:20427,cpu6,guvcview,8]uvcvideo: Device requested 27= 52512 B/frame bandwidth. [ 218.632598] [pid:20427,cpu6,guvcview,9]uvcvideo: No fast enough alt = setting for requested bandwidth. When dwMaxPayloadTransferSize is greater than maxpsize, it will prevent the camera from starting. So use the bandwidth of maxpsize. Signed-off-by: chenchangcheng Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202505072016.LlOxF8BG-lkp@int= el.com/ --- drivers/media/usb/uvc/uvc_video.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_= video.c index e3567aeb0007..0d5c17509ceb 100644 --- a/drivers/media/usb/uvc/uvc_video.c +++ b/drivers/media/usb/uvc/uvc_video.c @@ -262,6 +262,15 @@ static void uvc_fixup_video_ctrl(struct uvc_streaming = *stream, =20 ctrl->dwMaxPayloadTransferSize =3D bandwidth; } + + if (stream->intf->num_altsetting > 1 && + ctrl->dwMaxPayloadTransferSize > stream->maxpsize) { + dev_warn_ratelimited(&stream->intf->dev, + "the max payload transmission size (%d) exceededs the size of the e= p max packet (%d). Using the max size.\n", + ctrl->dwMaxPayloadTransferSize, + stream->maxpsize); + ctrl->dwMaxPayloadTransferSize =3D stream->maxpsize; + } } =20 static size_t uvc_video_ctrl_size(struct uvc_streaming *stream) base-commit: b4432656b36e5cc1d50a1f2dc15357543add530e --=20 2.25.1