From 6fa6f831f0950bf46934e6c3a9766b258a9ea85f Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Mon, 21 May 2018 04:54:40 -0400 Subject: media: v4l2-ctrls: add core request support 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 Reviewed-by: Mauro Carvalho Chehab Signed-off-by: Mauro Carvalho Chehab --- include/media/v4l2-ctrls.h | 51 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) (limited to 'include/media/v4l2-ctrls.h') 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 */ /** -- cgit v1.2.3