From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 969B4C433E1 for ; Tue, 23 Jun 2020 08:23:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 662EB2072E for ; Tue, 23 Jun 2020 08:23:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="YP1lM7ct" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731707AbgFWIX1 (ORCPT ); Tue, 23 Jun 2020 04:23:27 -0400 Received: from mail29.static.mailgun.info ([104.130.122.29]:33784 "EHLO mail29.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731603AbgFWIXZ (ORCPT ); Tue, 23 Jun 2020 04:23:25 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1592900603; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=0vR+p/RMWPL1tQ7TRskIM07erg5V5Hlq81AC+gIktnI=; b=YP1lM7ctrmU6SRg3j/nM0YacNOWqnWtI9y/Gqmmu2uiztuoTtpS/twx7CjlfnIw4EnxQHGXM XmL0jfSKuqXIA2hxVUb1F4Y+jmvObiv7zF8IbR43skhkPPWP4OyhPPbhnF2f1X6f5vsZdHOg kVnxjUkgzwbAJWo9jqRmJFjK5/E= X-Mailgun-Sending-Ip: 104.130.122.29 X-Mailgun-Sid: WyI1YmJiNiIsICJkZXZpY2V0cmVlQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n07.prod.us-west-2.postgun.com with SMTP id 5ef1bbec117610c7ff3268b0 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Tue, 23 Jun 2020 08:23:08 GMT Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 81B97C433A0; Tue, 23 Jun 2020 08:23:08 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: dikshita) by smtp.codeaurora.org (Postfix) with ESMTPSA id 50660C433C6; Tue, 23 Jun 2020 08:23:06 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Tue, 23 Jun 2020 13:53:06 +0530 From: dikshita@codeaurora.org To: Yunfei Dong Cc: Hans Verkuil , Tiffany Lin , Rob Herring , Mauro Carvalho Chehab , Mark Rutland , Matthias Brugger , linux-media@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, Tomasz Figa , linux-media-owner@vger.kernel.org Subject: Re: [PATCH v2, 2/2] media: v4l: Add Ro request api for capture queue In-Reply-To: <20200622015227.24134-3-yunfei.dong@mediatek.com> References: <20200622015227.24134-1-yunfei.dong@mediatek.com> <20200622015227.24134-3-yunfei.dong@mediatek.com> Message-ID: <9ce7d36bd34dd30a68309e5c55321bbd@codeaurora.org> X-Sender: dikshita@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Yunfei Dong, Thanks for the patch. I believe there is one additional change required in vb2_core_queue_init() to allow ro request if the driver sets supports_ro_requests while queue_init. thanks, Dikshita On 2020-06-22 07:22, Yunfei Dong wrote: > Add Read-only(Ro) request for capture queue. Ro request mean that > user driver can get ext ctrls, buf set ext ctrls is not allowed. > > Add param ro_requests in struct v4l2_ctrl_handler to present current > ctrl is read only. Add param ro_ctrl_handler in struct v4l2_fh used > for ro request. > > When set/get ext ctrls, will check whether current CID ctrls is ro > ctrls > or not using function v4l2_check_ro_ext_ctrls(). > > Signed-off-by: Yunfei Dong > --- > .../media/common/videobuf2/videobuf2-v4l2.c | 7 ++ > drivers/media/mc/mc-request.c | 10 +- > drivers/media/v4l2-core/v4l2-ctrls.c | 107 +++++++++++++++--- > drivers/media/v4l2-core/v4l2-ioctl.c | 22 ++++ > drivers/media/v4l2-core/v4l2-mem2mem.c | 19 ++-- > include/media/v4l2-ctrls.h | 22 +++- > include/media/v4l2-fh.h | 2 + > include/media/videobuf2-core.h | 2 + > include/uapi/linux/videodev2.h | 1 + > 9 files changed, 154 insertions(+), 38 deletions(-) > > diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c > b/drivers/media/common/videobuf2/videobuf2-v4l2.c > index eb5d5db96552..91a6f3a0c208 100644 > --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c > +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c > @@ -402,6 +402,11 @@ static int vb2_queue_or_prepare_buf(struct > vb2_queue *q, struct media_device *md > return -EBUSY; > } > return 0; > + } else if (!V4L2_TYPE_IS_OUTPUT(q->type)) { > + if (!q->supports_ro_requests || q->supports_requests) { > + dprintk(1, "%s: cap queue use ro requests\n", opname); > + return -EBADR; > + } > } else if (!q->supports_requests) { > dprintk(1, "%s: queue does not support requests\n", opname); > return -EBADR; > @@ -665,6 +670,8 @@ static void fill_buf_caps(struct vb2_queue *q, u32 > *caps) > #ifdef CONFIG_MEDIA_CONTROLLER_REQUEST_API > if (q->supports_requests) > *caps |= V4L2_BUF_CAP_SUPPORTS_REQUESTS; > + if (q->supports_ro_requests) > + *caps |= V4L2_BUF_CAP_SUPPORTS_RO_REQUESTS; > #endif > } > > diff --git a/drivers/media/mc/mc-request.c > b/drivers/media/mc/mc-request.c > index e3fca436c75b..e50ae259c1ff 100644 > --- a/drivers/media/mc/mc-request.c > +++ b/drivers/media/mc/mc-request.c > @@ -404,16 +404,12 @@ int media_request_object_bind(struct > media_request *req, > struct media_request_object *obj) > { > unsigned long flags; > - int ret = -EBUSY; > > if (WARN_ON(!ops->release)) > return -EBADR; > > spin_lock_irqsave(&req->lock, flags); > > - if (WARN_ON(req->state != MEDIA_REQUEST_STATE_UPDATING)) > - goto unlock; > - > obj->req = req; > obj->ops = ops; > obj->priv = priv; > @@ -423,11 +419,9 @@ int media_request_object_bind(struct media_request > *req, > else > list_add(&obj->list, &req->objects); > req->num_incomplete_objects++; > - ret = 0; > - > -unlock: > spin_unlock_irqrestore(&req->lock, flags); > - return ret; > + > + return 0; > } > EXPORT_SYMBOL_GPL(media_request_object_bind); > > diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c > b/drivers/media/v4l2-core/v4l2-ctrls.c > index 3f3fbcd60cc6..effc26f733de 100644 > --- a/drivers/media/v4l2-core/v4l2-ctrls.c > +++ b/drivers/media/v4l2-core/v4l2-ctrls.c > @@ -3386,22 +3386,6 @@ static const struct media_request_object_ops > req_ops = { > .release = v4l2_ctrl_request_release, > }; > > -struct v4l2_ctrl_handler *v4l2_ctrl_request_hdl_find(struct > media_request *req, > - struct v4l2_ctrl_handler *parent) > -{ > - struct media_request_object *obj; > - > - if (WARN_ON(req->state != MEDIA_REQUEST_STATE_VALIDATING && > - req->state != MEDIA_REQUEST_STATE_QUEUED)) > - return NULL; > - > - obj = media_request_object_find(req, &req_ops, parent); > - if (obj) > - return container_of(obj, struct v4l2_ctrl_handler, req_obj); > - return NULL; > -} > -EXPORT_SYMBOL_GPL(v4l2_ctrl_request_hdl_find); > - > struct v4l2_ctrl * > v4l2_ctrl_request_hdl_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id) > { > @@ -3420,6 +3404,10 @@ static int v4l2_ctrl_request_bind(struct > media_request *req, > ret = v4l2_ctrl_request_clone(hdl, from); > > if (!ret) { > + if (!hdl->ro_requests && > + WARN_ON(req->state != MEDIA_REQUEST_STATE_UPDATING)) > + return -EBUSY; > + > ret = media_request_object_bind(req, &req_ops, > from, false, &hdl->req_obj); > if (!ret) > @@ -3593,6 +3581,62 @@ static int class_check(struct v4l2_ctrl_handler > *hdl, u32 which) > return find_ref_lock(hdl, which | 1) ? 0 : -EINVAL; > } > > +int v4l2_check_ro_ext_ctrls(struct v4l2_ctrl_handler *hdl, > + struct video_device *vdev, struct media_device *mdev, > + struct v4l2_ext_controls *cs) > +{ > + struct v4l2_ctrl_ref *ref; > + u32 i; > + > + if (cs->which == V4L2_CTRL_WHICH_REQUEST_VAL) { > + if (!mdev || cs->request_fd < 0) > + return -EINVAL; > + } > + > + cs->error_idx = cs->count; > + cs->which = V4L2_CTRL_ID2WHICH(cs->which); > + > + if (hdl == NULL) > + return -EINVAL; > + > + if (cs->count == 0) > + return class_check(hdl, cs->which); > + > + for (i = 0; i < cs->count; i++) { > + struct v4l2_ext_control *c = &cs->controls[i]; > + u32 id = c->id & V4L2_CTRL_ID_MASK; > + > + cs->error_idx = i; > + > + if (cs->which && > + cs->which != V4L2_CTRL_WHICH_DEF_VAL && > + cs->which != V4L2_CTRL_WHICH_REQUEST_VAL && > + V4L2_CTRL_ID2WHICH(id) != cs->which) { > + dprintk(vdev, > + "invalid which 0x%x or control id 0x%x\n", > + cs->which, id); > + return -EINVAL; > + } > + > + /* Old-style private controls are not allowed for > + *extended controls > + */ > + if (id >= V4L2_CID_PRIVATE_BASE) { > + dprintk(vdev, > + "old-style private controls not allowed\n"); > + return -EINVAL; > + } > + > + ref = find_ref_lock(hdl, id); > + if (ref == NULL) { > + dprintk(vdev, "cannot find control id 0x%x\n", id); > + return -EINVAL; > + } > + } > + return 0; > +} > +EXPORT_SYMBOL(v4l2_check_ro_ext_ctrls); > + > /* Get extended controls. Allocates the helpers array if needed. */ > static int v4l2_g_ext_ctrls_common(struct v4l2_ctrl_handler *hdl, > struct v4l2_ext_controls *cs, > @@ -3694,7 +3738,7 @@ v4l2_ctrls_find_req_obj(struct v4l2_ctrl_handler > *hdl, > obj = media_request_object_find(req, &req_ops, hdl); > if (obj) > return obj; > - if (!set) > + if (!set && !hdl->ro_requests) > return ERR_PTR(-ENOENT); > > new_hdl = kzalloc(sizeof(*new_hdl), GFP_KERNEL); > @@ -3702,6 +3746,7 @@ v4l2_ctrls_find_req_obj(struct v4l2_ctrl_handler > *hdl, > return ERR_PTR(-ENOMEM); > > obj = &new_hdl->req_obj; > + new_hdl->ro_requests = hdl->ro_requests; > ret = v4l2_ctrl_handler_init(new_hdl, (hdl->nr_of_buckets - 1) * 8); > if (!ret) > ret = v4l2_ctrl_request_bind(req, new_hdl, hdl); > @@ -3763,6 +3808,28 @@ int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler > *hdl, struct video_device *vdev, > } > EXPORT_SYMBOL(v4l2_g_ext_ctrls); > > +struct v4l2_ctrl_handler *v4l2_ctrl_request_hdl_find(struct > media_request *req, > + struct v4l2_ctrl_handler *parent) > +{ > + struct media_request_object *obj; > + > + if (WARN_ON(req->state != MEDIA_REQUEST_STATE_VALIDATING && > + req->state != MEDIA_REQUEST_STATE_QUEUED)) > + return NULL; > + > + obj = media_request_object_find(req, &req_ops, parent); > + if (!obj) { > + if (parent->ro_requests) { > + obj = v4l2_ctrls_find_req_obj(parent, req, false); > + if (IS_ERR(obj)) > + return NULL; > + } else > + return NULL; > + } > + return container_of(obj, struct v4l2_ctrl_handler, req_obj); > +} > +EXPORT_SYMBOL_GPL(v4l2_ctrl_request_hdl_find); > + > /* Helper function to get a single control */ > static int get_ctrl(struct v4l2_ctrl *ctrl, struct v4l2_ext_control > *c) > { > @@ -4094,6 +4161,12 @@ static int try_set_ext_ctrls(struct v4l2_fh *fh, > int ret; > > if (cs->which == V4L2_CTRL_WHICH_REQUEST_VAL) { > + if (hdl->ro_requests) { > + dprintk(vdev, "%s: ro requests can`t set ext ctrls\n", > + video_device_node_name(vdev)); > + return -EINVAL; > + } > + > if (!mdev) { > dprintk(vdev, "%s: missing media device\n", > video_device_node_name(vdev)); > diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c > b/drivers/media/v4l2-core/v4l2-ioctl.c > index 2322f08a98be..b9e1058a5067 100644 > --- a/drivers/media/v4l2-core/v4l2-ioctl.c > +++ b/drivers/media/v4l2-core/v4l2-ioctl.c > @@ -2270,6 +2270,13 @@ static int v4l_g_ext_ctrls(const struct > v4l2_ioctl_ops *ops, > test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags) ? fh : NULL; > > p->error_idx = p->count; > + if (vfh && vfh->ro_ctrl_handler) { > + if (!v4l2_check_ro_ext_ctrls(vfh->ro_ctrl_handler, vfd, > + vfd->v4l2_dev->mdev, p)) { > + return v4l2_g_ext_ctrls(vfh->ro_ctrl_handler, vfd, > + vfd->v4l2_dev->mdev, p); > + } > + } > if (vfh && vfh->ctrl_handler) > return v4l2_g_ext_ctrls(vfh->ctrl_handler, > vfd, vfd->v4l2_dev->mdev, p); > @@ -2291,6 +2298,14 @@ static int v4l_s_ext_ctrls(const struct > v4l2_ioctl_ops *ops, > test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags) ? fh : NULL; > > p->error_idx = p->count; > + if (vfh && vfh->ro_ctrl_handler) { > + if (!v4l2_check_ro_ext_ctrls(vfh->ro_ctrl_handler, vfd, > + vfd->v4l2_dev->mdev, p)) { > + return v4l2_s_ext_ctrls(vfh, vfh->ro_ctrl_handler, vfd, > + vfd->v4l2_dev->mdev, p); > + } > + } > + > if (vfh && vfh->ctrl_handler) > return v4l2_s_ext_ctrls(vfh, vfh->ctrl_handler, > vfd, vfd->v4l2_dev->mdev, p); > @@ -2312,6 +2327,13 @@ static int v4l_try_ext_ctrls(const struct > v4l2_ioctl_ops *ops, > test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags) ? fh : NULL; > > p->error_idx = p->count; > + if (vfh && vfh->ro_ctrl_handler) { > + if (!v4l2_check_ro_ext_ctrls(vfh->ro_ctrl_handler, vfd, > + vfd->v4l2_dev->mdev, p)) { > + return v4l2_try_ext_ctrls(vfh->ro_ctrl_handler, vfd, > + vfd->v4l2_dev->mdev, p); > + } > + } > if (vfh && vfh->ctrl_handler) > return v4l2_try_ext_ctrls(vfh->ctrl_handler, > vfd, vfd->v4l2_dev->mdev, p); > diff --git a/drivers/media/v4l2-core/v4l2-mem2mem.c > b/drivers/media/v4l2-core/v4l2-mem2mem.c > index 62ac9424c92a..166e94ee18a7 100644 > --- a/drivers/media/v4l2-core/v4l2-mem2mem.c > +++ b/drivers/media/v4l2-core/v4l2-mem2mem.c > @@ -712,13 +712,6 @@ int v4l2_m2m_qbuf(struct file *file, struct > v4l2_m2m_ctx *m2m_ctx, > int ret; > > vq = v4l2_m2m_get_vq(m2m_ctx, buf->type); > - if (!V4L2_TYPE_IS_OUTPUT(vq->type) && > - (buf->flags & V4L2_BUF_FLAG_REQUEST_FD)) { > - dprintk("%s: requests cannot be used with capture buffers\n", > - __func__); > - return -EPERM; > - } > - > ret = vb2_qbuf(vq, vdev->v4l2_dev->mdev, buf); > if (ret) > return ret; > @@ -1252,10 +1245,14 @@ void v4l2_m2m_request_queue(struct > media_request *req) > if (vb2_request_object_is_buffer(obj)) { > /* Sanity checks */ > vb = container_of(obj, struct vb2_buffer, req_obj); > - WARN_ON(!V4L2_TYPE_IS_OUTPUT(vb->vb2_queue->type)); > - m2m_ctx_obj = container_of(vb->vb2_queue, > - struct v4l2_m2m_ctx, > - out_q_ctx.q); > + if (V4L2_TYPE_IS_OUTPUT(vb->vb2_queue->type)) > + m2m_ctx_obj = container_of(vb->vb2_queue, > + struct v4l2_m2m_ctx, > + out_q_ctx.q); > + else > + m2m_ctx_obj = container_of(vb->vb2_queue, > + struct v4l2_m2m_ctx, > + cap_q_ctx.q); > WARN_ON(m2m_ctx && m2m_ctx_obj != m2m_ctx); > m2m_ctx = m2m_ctx_obj; > } > diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h > index f40e2cbb21d3..5b10c2e8a402 100644 > --- a/include/media/v4l2-ctrls.h > +++ b/include/media/v4l2-ctrls.h > @@ -345,6 +345,7 @@ struct v4l2_ctrl_ref { > * @nr_of_buckets: Total number of buckets in the array. > * @error: The error code of the first failed control addition. > * @request_is_queued: True if the request was queued. > + * @ro_requests: True if the queue support ro request. > * @requests: List to keep track of open control handler request > objects. > * For the parent control handler (@req_obj.req == NULL) this > * is the list header. When the parent control handler is > @@ -368,6 +369,7 @@ struct v4l2_ctrl_handler { > u16 nr_of_buckets; > int error; > bool request_is_queued; > + bool ro_requests; > struct list_head requests; > struct list_head requests_queued; > struct media_request_object req_obj; > @@ -1261,8 +1263,10 @@ void v4l2_ctrl_request_complete(struct > media_request *req, > * @parent: The parent control handler ('priv' in > media_request_object_find()) > * > * This function finds the control handler in the request. It may > return > - * NULL if not found. When done, you must call > v4l2_ctrl_request_put_hdl() > - * with the returned handler pointer. > + * NULL if not found. But for Ro Request, the request object maybe > + * NULL, need to call v4l2_ctrls_find_req_obj() to check whether the > + * request has request object. When done, you must call > + * v4l2_ctrl_request_put_hdl() with the returned handler pointer. > * > * If the request is not in state VALIDATING or QUEUED, then this > function > * will always return NULL. > @@ -1454,4 +1458,18 @@ int v4l2_ctrl_subdev_log_status(struct > v4l2_subdev *sd); > int v4l2_ctrl_new_fwnode_properties(struct v4l2_ctrl_handler *hdl, > const struct v4l2_ctrl_ops *ctrl_ops, > const struct v4l2_fwnode_device_properties *p); > +/** > + * v4l2_check_ro_ext_ctrls - Check whether the ext controls are ro > request > + * > + * @hdl: pointer to &struct v4l2_ctrl_handler > + * @vdev: pointer to &struct video_device > + * @mdev: pointer to &struct media_device > + * @cs: pointer to &struct v4l2_ext_controls > + * > + * If hdl == NULL then they will all return -EINVAL. > + */ > +int v4l2_check_ro_ext_ctrls(struct v4l2_ctrl_handler *hdl, > + struct video_device *vdev, > + struct media_device *mdev, > + struct v4l2_ext_controls *cs); > #endif > diff --git a/include/media/v4l2-fh.h b/include/media/v4l2-fh.h > index b5b3e00c8e6a..479abef6c910 100644 > --- a/include/media/v4l2-fh.h > +++ b/include/media/v4l2-fh.h > @@ -27,6 +27,7 @@ struct v4l2_ctrl_handler; > * @list: list of file handlers > * @vdev: pointer to &struct video_device > * @ctrl_handler: pointer to &struct v4l2_ctrl_handler > + * @ro_ctrl_handler: pointer to &struct v4l2_ctrl_handler used for ro > ctrls > * @prio: priority of the file handler, as defined by &enum > v4l2_priority > * > * @wait: event' s wait queue > @@ -43,6 +44,7 @@ struct v4l2_fh { > struct list_head list; > struct video_device *vdev; > struct v4l2_ctrl_handler *ctrl_handler; > + struct v4l2_ctrl_handler *ro_ctrl_handler; > enum v4l2_priority prio; > > /* Events */ > diff --git a/include/media/videobuf2-core.h > b/include/media/videobuf2-core.h > index f11b96514cf7..dce5c6781be9 100644 > --- a/include/media/videobuf2-core.h > +++ b/include/media/videobuf2-core.h > @@ -483,6 +483,7 @@ struct vb2_buf_ops { > * has not been called. This is a vb1 idiom that has been > adopted > * also by vb2. > * @supports_requests: this queue supports the Request API. > + * @supports_ro_requests: this queue supports the RO Request API. > * @requires_requests: this queue requires the Request API. If this > is set to 1, > * then supports_requests must be set to 1 as well. > * @uses_qbuf: qbuf was used directly for this queue. Set to 1 the > first > @@ -564,6 +565,7 @@ struct vb2_queue { > unsigned allow_zero_bytesused:1; > unsigned quirk_poll_must_check_waiting_for_buffers:1; > unsigned supports_requests:1; > + unsigned supports_ro_requests:1; > unsigned requires_requests:1; > unsigned uses_qbuf:1; > unsigned uses_requests:1; > diff --git a/include/uapi/linux/videodev2.h > b/include/uapi/linux/videodev2.h > index c3a1cf1c507f..25793c737eab 100644 > --- a/include/uapi/linux/videodev2.h > +++ b/include/uapi/linux/videodev2.h > @@ -954,6 +954,7 @@ struct v4l2_requestbuffers { > #define V4L2_BUF_CAP_SUPPORTS_REQUESTS (1 << 3) > #define V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS (1 << 4) > #define V4L2_BUF_CAP_SUPPORTS_M2M_HOLD_CAPTURE_BUF (1 << 5) > +#define V4L2_BUF_CAP_SUPPORTS_RO_REQUESTS (1 << 6) > > /** > * struct v4l2_plane - plane info for multi-planar buffers