From nobody Tue Feb 10 20:49:45 2026 Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [185.203.201.7]) (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 3C42F158A00 for ; Tue, 9 Apr 2024 21:25:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.203.201.7 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712697906; cv=none; b=aymTB3aaBlIeH/2qh1ARnThUbFYA33BIAqiAx5hTSBUCTgrNSc8ylsHzv+/ToWpE605XQB5JcujP43LsQOJxt31pBwW/KQm6iXkI6fGc4XNAEyVVrzuIQEwspE3heQnSfx7kVxQmmmJwvLw30QavGKTpFJ49kHKhUb0LwxTBXYU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712697906; c=relaxed/simple; bh=6TmMXgCfd8u3hiqGzGhPNGk2tjA7rmKiDfupaGxCdqY=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=lUlZBIWAt+tUJcRTd1jFrgm5rpG/LXOfJftiJBoYBXesVDLzrrAobRjGy4LZr9cZ2m3O9RJDCFjUHdQFw5o+yUeSCmye5Ju9KAwBmHebo6faB0Jx4Y3FboCn6whg1+cejjtvHcPZrb5OmZGmIP3HAGyHSKuq4ugCOUqcFV2ygNM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de; spf=pass smtp.mailfrom=pengutronix.de; arc=none smtp.client-ip=185.203.201.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pengutronix.de Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ruIxf-00081a-FR; Tue, 09 Apr 2024 23:24:59 +0200 Received: from [2a0a:edc0:0:1101:1d::ac] (helo=dude04.red.stw.pengutronix.de) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1ruIxe-00BNAg-RD; Tue, 09 Apr 2024 23:24:58 +0200 Received: from localhost ([::1] helo=dude04.red.stw.pengutronix.de) by dude04.red.stw.pengutronix.de with esmtp (Exim 4.96) (envelope-from ) id 1ruIxe-00FQKu-2U; Tue, 09 Apr 2024 23:24:58 +0200 From: Michael Grzeschik Date: Tue, 09 Apr 2024 23:24:59 +0200 Subject: [PATCH 3/3] usb: gadget: uvc: set req_size and n_requests based on the frame interval Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20240403-uvc_request_length_by_interval-v1-3-9436c4716233@pengutronix.de> References: <20240403-uvc_request_length_by_interval-v1-0-9436c4716233@pengutronix.de> In-Reply-To: <20240403-uvc_request_length_by_interval-v1-0-9436c4716233@pengutronix.de> To: Laurent Pinchart , Daniel Scally , Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Michael Grzeschik X-Mailer: b4 0.12.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3029; i=m.grzeschik@pengutronix.de; h=from:subject:message-id; bh=6TmMXgCfd8u3hiqGzGhPNGk2tjA7rmKiDfupaGxCdqY=; b=owEBbQKS/ZANAwAKAb9pWET5cfSrAcsmYgBmFbIq8jorVF6Ra+5mJRuXSj4fgO1Wmk6Jc6g/c z+9XExEyRiJAjMEAAEKAB0WIQQV2+2Fpbqd6fvv0Gi/aVhE+XH0qwUCZhWyKgAKCRC/aVhE+XH0 q5GlD/41zsRHDlttuBY8aTSvLZ4Z0E1s/v6sAlwkr0KEtGGKpkobKgX9bZCSmG5EuXbud/1PdK9 AnvGzCML8QinMlVgbW4RcH9C8u0zi7fTSrA8Nf5BHxkltxPBB/WU2OGndNhIRcuhpIESPeSoFR2 aNn20ut0OoIbWvm+Pijn+23AZrPzbKrUgEzciMpXUxgsga4TrHIl+mJ7tj9ZLX4D1+tBcgiigr+ nKNPRlmm6tlGYif/y783CXHNAOcVbDwKqXwoI5Y5eeSUt5piG2RlFdjM37RiBZHpIDczQ6k16jl 2Qy5tsiuPmb9uK4mEDkj172k2X3bx0uYy4c2mYHl9mRSVrdc6enW8qjgvHdN4j0YOJPR2yLAiXj hyhzb5qso8uE7zzhvkbepVhofltCmsElEV+0szV1Lauk8j+2qnh7Boyk+z6rqx2XA2pKByDinrW /QvZ0XuZkIuRScFwu2N+HBmj4fslYLU00HIXLBloxX9PlKSfX+7iIoKHS84xAt85AOR2oTSRH8U u2uaNtsmmJOgYxxe7bdHaeGo8FhAj8WgZOpICOLEzcnNBk4aRD5+UoPMyR8uR09RI2e5UyfselM ycriv1tooV00FjvjGXF9TxVrtMGXUHVan14u5p3ARSn/PgNRI3gO3FSgoVDo4PgdwwK7/+j6nSq UNTpkS1XxCJSKJw== X-Developer-Key: i=m.grzeschik@pengutronix.de; a=openpgp; fpr=957BC452CE953D7EA60CF4FC0BE9E3157A1E2C64 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: m.grzeschik@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org With the information of the interval frame length it is now possible to calculate the number of usb requests by the frame duration. Based on the request size and the imagesize we calculate the actual size per request. This has calculation has the benefit that the frame data is equally distributed over all allocated requests. We keep the current req_size calculation as a fallback, if the interval callbacks did not set the interval property. Signed-off-by: Michael Grzeschik --- drivers/usb/gadget/function/uvc_queue.c | 28 +++++++++++++++++++++------- drivers/usb/gadget/function/uvc_video.c | 2 +- 2 files changed, 22 insertions(+), 8 deletions(-) diff --git a/drivers/usb/gadget/function/uvc_queue.c b/drivers/usb/gadget/f= unction/uvc_queue.c index ce51643fc4639..cd8a9793aa72e 100644 --- a/drivers/usb/gadget/function/uvc_queue.c +++ b/drivers/usb/gadget/function/uvc_queue.c @@ -44,7 +44,7 @@ static int uvc_queue_setup(struct vb2_queue *vq, { struct uvc_video_queue *queue =3D vb2_get_drv_priv(vq); struct uvc_video *video =3D container_of(queue, struct uvc_video, queue); - unsigned int req_size; + unsigned int req_size, max_req_size; unsigned int nreq; =20 if (*nbuffers > UVC_MAX_VIDEO_BUFFERS) @@ -54,15 +54,29 @@ static int uvc_queue_setup(struct vb2_queue *vq, =20 sizes[0] =3D video->imagesize; =20 - req_size =3D video->ep->maxpacket + nreq =3D DIV_ROUND_UP(video->interval, video->ep->desc->bInterval * 1250); + + req_size =3D DIV_ROUND_UP(sizes[0], nreq); + + max_req_size =3D video->ep->maxpacket * max_t(unsigned int, video->ep->maxburst, 1) * (video->ep->mult); =20 - /* We divide by two, to increase the chance to run - * into fewer requests for smaller framesizes. - */ - nreq =3D DIV_ROUND_UP(DIV_ROUND_UP(sizes[0], 2), req_size); - nreq =3D clamp(nreq, 4U, 64U); + if (!req_size) { + req_size =3D max_req_size; + + /* We divide by two, to increase the chance to run + * into fewer requests for smaller framesizes. + */ + nreq =3D DIV_ROUND_UP(DIV_ROUND_UP(sizes[0], 2), req_size); + nreq =3D clamp(nreq, 4U, 64U); + } else if (req_size > max_req_size) { + /* The prepared interval length and expected buffer size + * is not possible to stream with the currently configured + * isoc bandwidth + */ + return -EINVAL; + } =20 video->req_size =3D req_size; video->uvc_num_requests =3D nreq; diff --git a/drivers/usb/gadget/function/uvc_video.c b/drivers/usb/gadget/f= unction/uvc_video.c index 95bb64e16f3da..d197c46e93fb4 100644 --- a/drivers/usb/gadget/function/uvc_video.c +++ b/drivers/usb/gadget/function/uvc_video.c @@ -304,7 +304,7 @@ static int uvcg_video_usb_req_queue(struct uvc_video *v= ideo, */ if (list_empty(&video->req_free) || ureq->last_buf || !(video->req_int_count % - DIV_ROUND_UP(video->uvc_num_requests, 4))) { + clamp(DIV_ROUND_UP(video->uvc_num_requests, 4), 4U, 16U))) { video->req_int_count =3D 0; req->no_interrupt =3D 0; } else { --=20 2.39.2