Em Tue, 14 Aug 2018 16:20:26 +0200
Hans Verkuil <hverk...@xs4all.nl> escreveu:
> From: Hans Verkuil <hans.verk...@cisco.com>
>
> Integrate the request support. This adds the v4l2_ctrl_request_complete
> and v4l2_ctrl_request_setup functions to complete a request and (as a
> helper function) to apply a request to the hardware.
>
> It takes care of queuing requests and correctly chaining control values
> in the request queue.
>
> Note that when a request is marked completed it will copy control values
> to the internal request state. This can be optimized in the future since
> this is sub-optimal when dealing with large compound and/or array controls.
>
> For the initial 'stateless codec' use-case the current implementation is
> sufficient.
>
> Signed-off-by: Hans Verkuil <hans.verk...@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+sams...@kernel.org>
> ---
> drivers/media/v4l2-core/v4l2-ctrls.c | 336 ++++++++++++++++++++++++++-
> include/media/v4l2-ctrls.h | 51 ++++
> 2 files changed, 381 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c
> b/drivers/media/v4l2-core/v4l2-ctrls.c
> index c20e74ba48ab..89e7bfee108f 100644
> --- a/drivers/media/v4l2-core/v4l2-ctrls.c
> +++ b/drivers/media/v4l2-core/v4l2-ctrls.c
> @@ -1668,6 +1668,13 @@ static int new_to_user(struct v4l2_ext_control *c,
> return ptr_to_user(c, ctrl, ctrl->p_new);
> }
>
> +/* Helper function: copy the request value back to the caller */
> +static int req_to_user(struct v4l2_ext_control *c,
> + struct v4l2_ctrl_ref *ref)
> +{
> + return ptr_to_user(c, ref->ctrl, ref->p_req);
> +}
> +
> /* Helper function: copy the initial control value back to the caller */
> static int def_to_user(struct v4l2_ext_control *c, struct v4l2_ctrl *ctrl)
> {
> @@ -1787,6 +1794,26 @@ static void cur_to_new(struct v4l2_ctrl *ctrl)
> ptr_to_ptr(ctrl, ctrl->p_cur, ctrl->p_new);
> }
>
> +/* Copy the new value to the request value */
> +static void new_to_req(struct v4l2_ctrl_ref *ref)
> +{
> + if (!ref)
> + return;
> + ptr_to_ptr(ref->ctrl, ref->ctrl->p_new, ref->p_req);
> + ref->req = ref;
> +}
> +
> +/* Copy the request value to the new value */
> +static void req_to_new(struct v4l2_ctrl_ref *ref)
> +{
> + if (!ref)
> + return;
> + if (ref->req)
> + ptr_to_ptr(ref->ctrl, ref->req->p_req, ref->ctrl->p_new);
> + else
> + ptr_to_ptr(ref->ctrl, ref->ctrl->p_cur, ref->ctrl->p_new);
> +}
> +
> /* Return non-zero if one or more of the controls in the cluster has a new
> value that differs from the current value. */
> static int cluster_changed(struct v4l2_ctrl *master)
> @@ -1896,6 +1923,9 @@ int v4l2_ctrl_handler_init_class(struct
> v4l2_ctrl_handler *hdl,
> lockdep_set_class_and_name(hdl->lock, key, name);
> INIT_LIST_HEAD(&hdl->ctrls);
> INIT_LIST_HEAD(&hdl->ctrl_refs);
> + INIT_LIST_HEAD(&hdl->requests);
> + INIT_LIST_HEAD(&hdl->requests_queued);
> + hdl->request_is_queued = false;
> hdl->nr_of_buckets = 1 + nr_of_controls_hint / 8;
> hdl->buckets = kvmalloc_array(hdl->nr_of_buckets,
> sizeof(hdl->buckets[0]),
> @@ -1916,6 +1946,14 @@ void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler
> *hdl)
> if (hdl == NULL || hdl->buckets == NULL)
> return;
>
> + if (!hdl->req_obj.req && !list_empty(&hdl->requests)) {
> + struct v4l2_ctrl_handler *req, *next_req;
> +
> + 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);
> + }
> + }
> mutex_lock(hdl->lock);
> /* Free all nodes */
> list_for_each_entry_safe(ref, next_ref, &hdl->ctrl_refs, node) {
> @@ -2837,6 +2875,123 @@ int v4l2_querymenu(struct v4l2_ctrl_handler *hdl,
> struct v4l2_querymenu *qm)
> }
> EXPORT_SYMBOL(v4l2_querymenu);
>
> +static int v4l2_ctrl_request_clone(struct v4l2_ctrl_handler *hdl,
> + const struct v4l2_ctrl_handler *from)
> +{
> + struct v4l2_ctrl_ref *ref;
> + int err;
> +
> + 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;
> + /* And buttons */
> + if (ctrl->type == V4L2_CTRL_TYPE_BUTTON)
> + 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;
> + struct v4l2_ctrl_handler *prev_hdl = NULL;
> + struct v4l2_ctrl_ref *ref_ctrl, *ref_ctrl_prev = NULL;
> +
> + if (list_empty(&main_hdl->requests_queued))
> + goto queue;
> +
> + prev_hdl = list_last_entry(&main_hdl->requests_queued,
> + struct v4l2_ctrl_handler, requests_queued);
> + /*
> + * Note: prev_hdl and hdl must contain the same list of control
> + * references, so if any differences are detected then that is a
> + * driver bug and the WARN_ON is triggered.
> + */
> + mutex_lock(prev_hdl->lock);
> + ref_ctrl_prev = list_first_entry(&prev_hdl->ctrl_refs,
> + struct v4l2_ctrl_ref, node);
> + list_for_each_entry(ref_ctrl, &hdl->ctrl_refs, node) {
> + if (ref_ctrl->req)
> + continue;
> + while (ref_ctrl_prev->ctrl->id < ref_ctrl->ctrl->id) {
> + /* Should never happen, but just in case... */
> + if (list_is_last(&ref_ctrl_prev->node,
> + &prev_hdl->ctrl_refs))
> + break;
> + ref_ctrl_prev = list_next_entry(ref_ctrl_prev, node);
> + }
> + if (WARN_ON(ref_ctrl_prev->ctrl->id != ref_ctrl->ctrl->id))
> + break;
> + ref_ctrl->req = ref_ctrl_prev->req;
> + }
> + mutex_unlock(prev_hdl->lock);
> +queue:
> + list_add_tail(&hdl->requests_queued, &main_hdl->requests_queued);
> + hdl->request_is_queued = true;
> +}
> +
> +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);
> +
> + list_del_init(&hdl->requests);
> + if (hdl->request_is_queued) {
> + list_del_init(&hdl->requests_queued);
> + hdl->request_is_queued = false;
> + }
> +}
> +
> +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,
> +};
> +
> +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)
> + list_add_tail(&hdl->requests, &from->requests);
> + }
> + return ret;
> +}
>
> /* Some general notes on the atomic requirements of VIDIOC_G/TRY/S_EXT_CTRLS:
>
> @@ -2898,6 +3053,7 @@ static int prepare_ext_ctrls(struct v4l2_ctrl_handler
> *hdl,
>
> if (cs->which &&
> cs->which != V4L2_CTRL_WHICH_DEF_VAL &&
> + cs->which != V4L2_CTRL_WHICH_REQUEST_VAL &&
> V4L2_CTRL_ID2WHICH(id) != cs->which)
> return -EINVAL;
>
> @@ -2977,13 +3133,12 @@ static int prepare_ext_ctrls(struct v4l2_ctrl_handler
> *hdl,
> whether there are any controls at all. */
> static int class_check(struct v4l2_ctrl_handler *hdl, u32 which)
> {
> - if (which == 0 || which == V4L2_CTRL_WHICH_DEF_VAL)
> + if (which == 0 || which == V4L2_CTRL_WHICH_DEF_VAL ||
> + which == V4L2_CTRL_WHICH_REQUEST_VAL)
> return 0;
> return find_ref_lock(hdl, which | 1) ? 0 : -EINVAL;
> }
>
> -
> -
> /* Get extended controls. Allocates the helpers array if needed. */
> int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls
> *cs)
> {
> @@ -3049,8 +3204,12 @@ int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl,
> struct v4l2_ext_controls *cs
> u32 idx = i;
>
> do {
> - ret = ctrl_to_user(cs->controls + idx,
> - helpers[idx].ref->ctrl);
> + if (helpers[idx].ref->req)
> + ret = req_to_user(cs->controls + idx,
> + helpers[idx].ref->req);
> + else
> + ret = ctrl_to_user(cs->controls + idx,
> + helpers[idx].ref->ctrl);
> idx = helpers[idx].next;
> } while (!ret && idx);
> }
> @@ -3336,7 +3495,16 @@ static int try_set_ext_ctrls(struct v4l2_fh *fh,
> struct v4l2_ctrl_handler *hdl,
> } while (!ret && idx);
>
> if (!ret)
> - ret = try_or_set_cluster(fh, master, set, 0);
> + ret = try_or_set_cluster(fh, master,
> + !hdl->req_obj.req && set, 0);
> + if (!ret && hdl->req_obj.req && set) {
> + for (j = 0; j < master->ncontrols; j++) {
> + struct v4l2_ctrl_ref *ref =
> + find_ref(hdl, master->cluster[j]->id);
> +
> + new_to_req(ref);
> + }
> + }
>
> /* Copy the new values back to userspace. */
> if (!ret) {
> @@ -3463,6 +3631,162 @@ int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl,
> const char *s)
> }
> EXPORT_SYMBOL(__v4l2_ctrl_s_ctrl_string);
>
> +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)
> + return;
> + 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) {
> + ref->req = ref;
> +
> + 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->req == ref)
> + continue;
> +
> + v4l2_ctrl_lock(ctrl);
> + if (ref->req)
> + ptr_to_ptr(ctrl, ref->req->p_req, ref->p_req);
> + else
> + ptr_to_ptr(ctrl, ctrl->p_cur, ref->p_req);
> + v4l2_ctrl_unlock(ctrl);
> + }
> +
> + WARN_ON(!hdl->request_is_queued);
> + list_del_init(&hdl->requests_queued);
> + hdl->request_is_queued = false;
> + media_request_object_complete(obj);
> + media_request_object_put(obj);
> +}
> +EXPORT_SYMBOL(v4l2_ctrl_request_complete);
> +
> +void 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;
> +
> + if (!req || !main_hdl)
> + return;
> +
> + if (WARN_ON(req->state != MEDIA_REQUEST_STATE_QUEUED))
> + 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)
> + return;
> + if (obj->completed) {
> + media_request_object_put(obj);
> + return;
> + }
> + 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->type == V4L2_CTRL_TYPE_BUTTON ||
> + (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->req && r == r->req) {
> + 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);
> +
> + req_to_new(r);
> + 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);
> + }
> +
> + try_or_set_cluster(NULL, master, true, 0);
> +
> + v4l2_ctrl_unlock(master);
> + }
> +
> + media_request_object_put(obj);
> +}
> +EXPORT_SYMBOL(v4l2_ctrl_request_setup);
> +
> void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify,
> void *priv)
> {
> if (ctrl == NULL)
> diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h
> index 3f4e062d4e3d..ed784e98c293 100644
> --- a/include/media/v4l2-ctrls.h
> +++ b/include/media/v4l2-ctrls.h
> @@ -250,6 +250,12 @@ struct v4l2_ctrl {
> * ``prepare_ext_ctrls`` function at ``v4l2-ctrl.c``.
> * @from_other_dev: If true, then @ctrl was defined in another
> * device than the &struct v4l2_ctrl_handler.
> + * @req_done: Internal flag: if the control handler containing this
> control
> + * reference is bound to a media request, then this is set when
> + * the control has been applied. This prevents applying controls
> + * from a cluster with multiple controls twice (when the first
> + * control of a cluster is applied, they all are).
> + * @req: If set, this refers to another request that sets this control.
> * @p_req: If the control handler containing this control reference
> * is bound to a media request, then this points to the
> * value of the control that should be applied when the request
> @@ -266,6 +272,8 @@ struct v4l2_ctrl_ref {
> struct v4l2_ctrl *ctrl;
> struct v4l2_ctrl_helper *helper;
> bool from_other_dev;
> + bool req_done;
> + struct v4l2_ctrl_ref *req;
> union v4l2_ctrl_ptr p_req;
> };
>
> @@ -290,6 +298,15 @@ struct v4l2_ctrl_ref {
> * @notify_priv: Passed as argument to the v4l2_ctrl notify callback.
> * @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.
> + * @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
> + * removed, it has to unbind and put all these requests since
> + * they refer to the parent.
> + * @requests_queued: List of the queued requests. This determines the order
> + * in which these controls are applied. Once the request is
> + * completed it is removed from this list.
> * @req_obj: The &struct media_request_object, used to link into a
> * &struct media_request. This request object has a refcount.
> */
> @@ -304,6 +321,9 @@ struct v4l2_ctrl_handler {
> void *notify_priv;
> u16 nr_of_buckets;
> int error;
> + bool request_is_queued;
> + struct list_head requests;
> + struct list_head requests_queued;
> struct media_request_object req_obj;
> };
>
> @@ -1062,6 +1082,37 @@ int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh,
> */
> __poll_t v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait);
>
> +/**
> + * v4l2_ctrl_request_setup - helper function to apply control values in a
> request
> + *
> + * @req: The request
> + * @parent: The parent control handler ('priv' in
> media_request_object_find())
> + *
> + * This is a helper function to call the control handler's s_ctrl callback
> with
> + * the control values contained in the request. Do note that this approach of
> + * applying control values in a request is only applicable to
> memory-to-memory
> + * devices.
> + */
> +void v4l2_ctrl_request_setup(struct media_request *req,
> + struct v4l2_ctrl_handler *parent);
> +
> +/**
> + * v4l2_ctrl_request_complete - Complete a control handler request object
> + *
> + * @req: The request
> + * @parent: The parent control handler ('priv' in
> media_request_object_find())
> + *
> + * This function is to be called on each control handler that may have had a
> + * request object associated with it, i.e. control handlers of a driver that
> + * supports requests.
> + *
> + * The function first obtains the values of any volatile controls in the
> control
> + * handler and attach them to the request. Then, the function completes the
> + * request object.
> + */
> +void v4l2_ctrl_request_complete(struct media_request *req,
> + struct v4l2_ctrl_handler *hdl);
> +
> /* Helpers for ioctl_ops */
>
> /**
Thanks,
Mauro
