OSCL-LXR linux-6.0.1/​drivers/​media/​v4l2-core/​v4l2-ctrls-request.c	Source navigation Diff markup Identifier search General search
	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * V4L2 controls framework Request API implementation.
  *
  * Copyright (C) 2018-2021  Hans Verkuil <hverkuil-cisco@xs4all.nl>
  */
 
 #define pr_fmt(fmt) "v4l2-ctrls: " fmt
 
 #include <linux/export.h>
 #include <linux/slab.h>
 #include <media/v4l2-ctrls.h>
 #include <media/v4l2-dev.h>
 #include <media/v4l2-ioctl.h>
 
 #include "v4l2-ctrls-priv.h"
 
 /* Initialize the request-related fields in a control handler */
 void v4l2_ctrl_handler_init_request(struct v4l2_ctrl_handler *hdl)
 {
     INIT_LIST_HEAD(&hdl->requests);
     INIT_LIST_HEAD(&hdl->requests_queued);
     hdl->request_is_queued = false;
     media_request_object_init(&hdl->req_obj);
 }
 
 /* Free the request-related fields in a control handler */
 void v4l2_ctrl_handler_free_request(struct v4l2_ctrl_handler *hdl)
 {
     struct v4l2_ctrl_handler *req, *next_req;
 
     /*
      * Do nothing if this isn't the main handler or the main
      * handler is not used in any request.
      *
      * The main handler can be identified by having a NULL ops pointer in
      * the request object.
      */
     if (hdl->req_obj.ops || list_empty(&hdl->requests))
         return;
 
     /*
      * If the main handler is freed and it is used by handler objects in
      * outstanding requests, then unbind and put those objects before
      * freeing the main handler.
      */
     list_for_each_entry_safe(req, next_req, &hdl->requests, requests) {
         media_request_object_unbind(&req->req_obj);
         media_request_object_put(&req->req_obj);
     }
 }
 
 static int v4l2_ctrl_request_clone(struct v4l2_ctrl_handler *hdl,
                    const struct v4l2_ctrl_handler *from)
 {
     struct v4l2_ctrl_ref *ref;
     int err = 0;
 
     if (WARN_ON(!hdl || hdl == from))
         return -EINVAL;
 
     if (hdl->error)
         return hdl->error;
 
     WARN_ON(hdl->lock != &hdl->_lock);
 
     mutex_lock(from->lock);
     list_for_each_entry(ref, &from->ctrl_refs, node) {
         struct v4l2_ctrl *ctrl = ref->ctrl;
         struct v4l2_ctrl_ref *new_ref;
 
         /* Skip refs inherited from other devices */
         if (ref->from_other_dev)
             continue;
         err = handler_new_ref(hdl, ctrl, &new_ref, false, true);
         if (err)
             break;
     }
     mutex_unlock(from->lock);
     return err;
 }
 
 static void v4l2_ctrl_request_queue(struct media_request_object *obj)
 {
     struct v4l2_ctrl_handler *hdl =
         container_of(obj, struct v4l2_ctrl_handler, req_obj);
     struct v4l2_ctrl_handler *main_hdl = obj->priv;
 
     mutex_lock(main_hdl->lock);
     list_add_tail(&hdl->requests_queued, &main_hdl->requests_queued);
     hdl->request_is_queued = true;
     mutex_unlock(main_hdl->lock);
 }
 
 static void v4l2_ctrl_request_unbind(struct media_request_object *obj)
 {
     struct v4l2_ctrl_handler *hdl =
         container_of(obj, struct v4l2_ctrl_handler, req_obj);
     struct v4l2_ctrl_handler *main_hdl = obj->priv;
 
     mutex_lock(main_hdl->lock);
     list_del_init(&hdl->requests);
     if (hdl->request_is_queued) {
         list_del_init(&hdl->requests_queued);
         hdl->request_is_queued = false;
     }
     mutex_unlock(main_hdl->lock);
 }
 
 static void v4l2_ctrl_request_release(struct media_request_object *obj)
 {
     struct v4l2_ctrl_handler *hdl =
         container_of(obj, struct v4l2_ctrl_handler, req_obj);
 
     v4l2_ctrl_handler_free(hdl);
     kfree(hdl);
 }
 
 static const struct media_request_object_ops req_ops = {
     .queue = v4l2_ctrl_request_queue,
     .unbind = v4l2_ctrl_request_unbind,
     .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)
 {
     struct v4l2_ctrl_ref *ref = find_ref_lock(hdl, id);
 
     return (ref && ref->p_req_valid) ? ref->ctrl : NULL;
 }
 EXPORT_SYMBOL_GPL(v4l2_ctrl_request_hdl_ctrl_find);
 
 static int v4l2_ctrl_request_bind(struct media_request *req,
                   struct v4l2_ctrl_handler *hdl,
                   struct v4l2_ctrl_handler *from)
 {
     int ret;
 
     ret = v4l2_ctrl_request_clone(hdl, from);
 
     if (!ret) {
         ret = media_request_object_bind(req, &req_ops,
                         from, false, &hdl->req_obj);
         if (!ret) {
             mutex_lock(from->lock);
             list_add_tail(&hdl->requests, &from->requests);
             mutex_unlock(from->lock);
         }
     }
     return ret;
 }
 
 static struct media_request_object *
 v4l2_ctrls_find_req_obj(struct v4l2_ctrl_handler *hdl,
             struct media_request *req, bool set)
 {
     struct media_request_object *obj;
     struct v4l2_ctrl_handler *new_hdl;
     int ret;
 
     if (IS_ERR(req))
         return ERR_CAST(req);
 
     if (set && WARN_ON(req->state != MEDIA_REQUEST_STATE_UPDATING))
         return ERR_PTR(-EBUSY);
 
     obj = media_request_object_find(req, &req_ops, hdl);
     if (obj)
         return obj;
     /*
      * If there are no controls in this completed request,
      * then that can only happen if:
      *
      * 1) no controls were present in the queued request, and
      * 2) v4l2_ctrl_request_complete() could not allocate a
      *    control handler object to store the completed state in.
      *
      * So return ENOMEM to indicate that there was an out-of-memory
      * error.
      */
     if (!set)
         return ERR_PTR(-ENOMEM);
 
     new_hdl = kzalloc(sizeof(*new_hdl), GFP_KERNEL);
     if (!new_hdl)
         return ERR_PTR(-ENOMEM);
 
     obj = &new_hdl->req_obj;
     ret = v4l2_ctrl_handler_init(new_hdl, (hdl->nr_of_buckets - 1) * 8);
     if (!ret)
         ret = v4l2_ctrl_request_bind(req, new_hdl, hdl);
     if (ret) {
         v4l2_ctrl_handler_free(new_hdl);
         kfree(new_hdl);
         return ERR_PTR(ret);
     }
 
     media_request_object_get(obj);
     return obj;
 }
 
 int v4l2_g_ext_ctrls_request(struct v4l2_ctrl_handler *hdl, struct video_device *vdev,
                  struct media_device *mdev, struct v4l2_ext_controls *cs)
 {
     struct media_request_object *obj = NULL;
     struct media_request *req = NULL;
     int ret;
 
     if (!mdev || cs->request_fd < 0)
         return -EINVAL;
 
     req = media_request_get_by_fd(mdev, cs->request_fd);
     if (IS_ERR(req))
         return PTR_ERR(req);
 
     if (req->state != MEDIA_REQUEST_STATE_COMPLETE) {
         media_request_put(req);
         return -EACCES;
     }
 
     ret = media_request_lock_for_access(req);
     if (ret) {
         media_request_put(req);
         return ret;
     }
 
     obj = v4l2_ctrls_find_req_obj(hdl, req, false);
     if (IS_ERR(obj)) {
         media_request_unlock_for_access(req);
         media_request_put(req);
         return PTR_ERR(obj);
     }
 
     hdl = container_of(obj, struct v4l2_ctrl_handler,
                req_obj);
     ret = v4l2_g_ext_ctrls_common(hdl, cs, vdev);
 
     media_request_unlock_for_access(req);
     media_request_object_put(obj);
     media_request_put(req);
     return ret;
 }
 
 int try_set_ext_ctrls_request(struct v4l2_fh *fh,
                   struct v4l2_ctrl_handler *hdl,
                   struct video_device *vdev,
                   struct media_device *mdev,
                   struct v4l2_ext_controls *cs, bool set)
 {
     struct media_request_object *obj = NULL;
     struct media_request *req = NULL;
     int ret;
 
     if (!mdev) {
         dprintk(vdev, "%s: missing media device\n",
             video_device_node_name(vdev));
         return -EINVAL;
     }
 
     if (cs->request_fd < 0) {
         dprintk(vdev, "%s: invalid request fd %d\n",
             video_device_node_name(vdev), cs->request_fd);
         return -EINVAL;
     }
 
     req = media_request_get_by_fd(mdev, cs->request_fd);
     if (IS_ERR(req)) {
         dprintk(vdev, "%s: cannot find request fd %d\n",
             video_device_node_name(vdev), cs->request_fd);
         return PTR_ERR(req);
     }
 
     ret = media_request_lock_for_update(req);
     if (ret) {
         dprintk(vdev, "%s: cannot lock request fd %d\n",
             video_device_node_name(vdev), cs->request_fd);
         media_request_put(req);
         return ret;
     }
 
     obj = v4l2_ctrls_find_req_obj(hdl, req, set);
     if (IS_ERR(obj)) {
         dprintk(vdev,
             "%s: cannot find request object for request fd %d\n",
             video_device_node_name(vdev),
             cs->request_fd);
         media_request_unlock_for_update(req);
         media_request_put(req);
         return PTR_ERR(obj);
     }
 
     hdl = container_of(obj, struct v4l2_ctrl_handler,
                req_obj);
     ret = try_set_ext_ctrls_common(fh, hdl, cs, vdev, set);
     if (ret)
         dprintk(vdev,
             "%s: try_set_ext_ctrls_common failed (%d)\n",
             video_device_node_name(vdev), ret);
 
     media_request_unlock_for_update(req);
     media_request_object_put(obj);
     media_request_put(req);
 
     return ret;
 }
 
 void v4l2_ctrl_request_complete(struct media_request *req,
                 struct v4l2_ctrl_handler *main_hdl)
 {
     struct media_request_object *obj;
     struct v4l2_ctrl_handler *hdl;
     struct v4l2_ctrl_ref *ref;
 
     if (!req || !main_hdl)
         return;
 
     /*
      * Note that it is valid if nothing was found. It means
      * that this request doesn't have any controls and so just
      * wants to leave the controls unchanged.
      */
     obj = media_request_object_find(req, &req_ops, main_hdl);
     if (!obj) {
         int ret;
 
         /* Create a new request so the driver can return controls */
         hdl = kzalloc(sizeof(*hdl), GFP_KERNEL);
         if (!hdl)
             return;
 
         ret = v4l2_ctrl_handler_init(hdl, (main_hdl->nr_of_buckets - 1) * 8);
         if (!ret)
             ret = v4l2_ctrl_request_bind(req, hdl, main_hdl);
         if (ret) {
             v4l2_ctrl_handler_free(hdl);
             kfree(hdl);
             return;
         }
         hdl->request_is_queued = true;
         obj = media_request_object_find(req, &req_ops, main_hdl);
     }
     hdl = container_of(obj, struct v4l2_ctrl_handler, req_obj);
 
     list_for_each_entry(ref, &hdl->ctrl_refs, node) {
         struct v4l2_ctrl *ctrl = ref->ctrl;
         struct v4l2_ctrl *master = ctrl->cluster[0];
         unsigned int i;
 
         if (ctrl->flags & V4L2_CTRL_FLAG_VOLATILE) {
             v4l2_ctrl_lock(master);
             /* g_volatile_ctrl will update the current control values */
             for (i = 0; i < master->ncontrols; i++)
                 cur_to_new(master->cluster[i]);
             call_op(master, g_volatile_ctrl);
             new_to_req(ref);
             v4l2_ctrl_unlock(master);
             continue;
         }
         if (ref->p_req_valid)
             continue;
 
         /* Copy the current control value into the request */
         v4l2_ctrl_lock(ctrl);
         cur_to_req(ref);
         v4l2_ctrl_unlock(ctrl);
     }
 
     mutex_lock(main_hdl->lock);
     WARN_ON(!hdl->request_is_queued);
     list_del_init(&hdl->requests_queued);
     hdl->request_is_queued = false;
     mutex_unlock(main_hdl->lock);
     media_request_object_complete(obj);
     media_request_object_put(obj);
 }
 EXPORT_SYMBOL(v4l2_ctrl_request_complete);
 
 int v4l2_ctrl_request_setup(struct media_request *req,
                 struct v4l2_ctrl_handler *main_hdl)
 {
     struct media_request_object *obj;
     struct v4l2_ctrl_handler *hdl;
     struct v4l2_ctrl_ref *ref;
     int ret = 0;
 
     if (!req || !main_hdl)
         return 0;
 
     if (WARN_ON(req->state != MEDIA_REQUEST_STATE_QUEUED))
         return -EBUSY;
 
     /*
      * Note that it is valid if nothing was found. It means
      * that this request doesn't have any controls and so just
      * wants to leave the controls unchanged.
      */
     obj = media_request_object_find(req, &req_ops, main_hdl);
     if (!obj)
         return 0;
     if (obj->completed) {
         media_request_object_put(obj);
         return -EBUSY;
     }
     hdl = container_of(obj, struct v4l2_ctrl_handler, req_obj);
 
     list_for_each_entry(ref, &hdl->ctrl_refs, node)
         ref->req_done = false;
 
     list_for_each_entry(ref, &hdl->ctrl_refs, node) {
         struct v4l2_ctrl *ctrl = ref->ctrl;
         struct v4l2_ctrl *master = ctrl->cluster[0];
         bool have_new_data = false;
         int i;
 
         /*
          * Skip if this control was already handled by a cluster.
          * Skip button controls and read-only controls.
          */
         if (ref->req_done || (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY))
             continue;
 
         v4l2_ctrl_lock(master);
         for (i = 0; i < master->ncontrols; i++) {
             if (master->cluster[i]) {
                 struct v4l2_ctrl_ref *r =
                     find_ref(hdl, master->cluster[i]->id);
 
                 if (r->p_req_valid) {
                     have_new_data = true;
                     break;
                 }
             }
         }
         if (!have_new_data) {
             v4l2_ctrl_unlock(master);
             continue;
         }
 
         for (i = 0; i < master->ncontrols; i++) {
             if (master->cluster[i]) {
                 struct v4l2_ctrl_ref *r =
                     find_ref(hdl, master->cluster[i]->id);
 
                 ret = req_to_new(r);
                 if (ret) {
                     v4l2_ctrl_unlock(master);
                     goto error;
                 }
                 master->cluster[i]->is_new = 1;
                 r->req_done = true;
             }
         }
         /*
          * For volatile autoclusters that are currently in auto mode
          * we need to discover if it will be set to manual mode.
          * If so, then we have to copy the current volatile values
          * first since those will become the new manual values (which
          * may be overwritten by explicit new values from this set
          * of controls).
          */
         if (master->is_auto && master->has_volatiles &&
             !is_cur_manual(master)) {
             s32 new_auto_val = *master->p_new.p_s32;
 
             /*
              * If the new value == the manual value, then copy
              * the current volatile values.
              */
             if (new_auto_val == master->manual_mode_value)
                 update_from_auto_cluster(master);
         }
 
         ret = try_or_set_cluster(NULL, master, true, 0);
         v4l2_ctrl_unlock(master);
 
         if (ret)
             break;
     }
 
 error:
     media_request_object_put(obj);
     return ret;
 }
 EXPORT_SYMBOL(v4l2_ctrl_request_setup);

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