From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from bombadil.infradead.org ([198.137.202.133]:49580 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752376AbeEGSGE (ORCPT ); Mon, 7 May 2018 14:06:04 -0400 Date: Mon, 7 May 2018 15:06:00 -0300 From: Mauro Carvalho Chehab To: Hans Verkuil Cc: linux-media@vger.kernel.org, Hans Verkuil Subject: Re: [PATCHv13 12/28] v4l2-ctrls: add core request support Message-ID: <20180507150600.66d794c6@vento.lan> In-Reply-To: <20180503145318.128315-13-hverkuil@xs4all.nl> References: <20180503145318.128315-1-hverkuil@xs4all.nl> <20180503145318.128315-13-hverkuil@xs4all.nl> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Em Thu, 3 May 2018 16:53:02 +0200 Hans Verkuil escreveu: > From: Hans Verkuil > > 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 > --- > drivers/media/v4l2-core/v4l2-ctrls.c | 331 ++++++++++++++++++++++++++- > include/media/v4l2-ctrls.h | 23 ++ > 2 files changed, 348 insertions(+), 6 deletions(-) > > diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c > index da4cc1485dc4..56b986185463 100644 > --- a/drivers/media/v4l2-core/v4l2-ctrls.c > +++ b/drivers/media/v4l2-core/v4l2-ctrls.c > @@ -1647,6 +1647,13 @@ 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) > { > @@ -1766,6 +1773,26 @@ 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) > @@ -1875,6 +1902,9 @@ 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]), > @@ -1895,6 +1925,14 @@ 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) { > @@ -2816,6 +2854,128 @@ 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) { > + printk("%s: handler_new_ref on control %x (%s) returned %d\n", __func__, ctrl->id, ctrl->name, err); > + err = 0; > + continue; > + } > + 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; Hmm... if the WARN_ON() is issued, should it still be queuing it? If there's a driver's bug, I suspect it would be better to do, instead: if (WARN_ON(ref_ctrl_prev->ctrl->id != ref_ctrl->ctrl->id)) { mutex_unlock(prev_hdl->lock); return; } > + 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, &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: > > @@ -2877,6 +3037,7 @@ 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; > > @@ -2956,13 +3117,12 @@ 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) > { > @@ -3028,8 +3188,12 @@ 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); > } > @@ -3302,7 +3466,16 @@ 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) { > @@ -3429,6 +3602,152 @@ 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; > + > + 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; > + > + 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); > + > + mutex_lock(hdl->lock); > + > + list_for_each_entry(ref, &hdl->ctrl_refs, node) > + ref->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->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->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); > + } > + > + mutex_unlock(hdl->lock); > + 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 76352eb59f14..a0f7c38d1a90 100644 > --- a/include/media/v4l2-ctrls.h > +++ b/include/media/v4l2-ctrls.h > @@ -250,6 +250,10 @@ 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. > + * @done: If true, then this control reference is part of a > + * control cluster that was already set while applying > + * the controls in this media request object. Hmm... I would rename it for request_done or something similar, as it seems that this applies only for requests. > + * @req: If set, this refers to another request that sets this control. > * @p_req: The request value. Only used if the control handler > * is bound to a media request. > * > @@ -263,6 +267,8 @@ struct v4l2_ctrl_ref { > struct v4l2_ctrl *ctrl; > struct v4l2_ctrl_helper *helper; > bool from_other_dev; > + bool done; > + struct v4l2_ctrl_ref *req; > union v4l2_ctrl_ptr p_req; > }; > > @@ -287,6 +293,15 @@ 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. > */ > @@ -301,6 +316,9 @@ 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; > }; > > @@ -1059,6 +1077,11 @@ int v4l2_ctrl_subscribe_event(struct v4l2_fh *fh, > */ > __poll_t v4l2_ctrl_poll(struct file *file, struct poll_table_struct *wait); > > +void v4l2_ctrl_request_setup(struct media_request *req, > + struct v4l2_ctrl_handler *hdl); > +void v4l2_ctrl_request_complete(struct media_request *req, > + struct v4l2_ctrl_handler *hdl); > + > /* Helpers for ioctl_ops */ > > /** Thanks, Mauro