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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /include/media/media-request.h | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'include/media/media-request.h')
-rw-r--r-- | include/media/media-request.h | 442 |
1 files changed, 442 insertions, 0 deletions
diff --git a/include/media/media-request.h b/include/media/media-request.h new file mode 100644 index 0000000000..3cd25a2717 --- /dev/null +++ b/include/media/media-request.h @@ -0,0 +1,442 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Media device request objects + * + * Copyright 2018 Cisco Systems, Inc. and/or its affiliates. All rights reserved. + * Copyright (C) 2018 Intel Corporation + * + * Author: Hans Verkuil <hans.verkuil@cisco.com> + * Author: Sakari Ailus <sakari.ailus@linux.intel.com> + */ + +#ifndef MEDIA_REQUEST_H +#define MEDIA_REQUEST_H + +#include <linux/list.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/refcount.h> + +#include <media/media-device.h> + +/** + * enum media_request_state - media request state + * + * @MEDIA_REQUEST_STATE_IDLE: Idle + * @MEDIA_REQUEST_STATE_VALIDATING: Validating the request, no state changes + * allowed + * @MEDIA_REQUEST_STATE_QUEUED: Queued + * @MEDIA_REQUEST_STATE_COMPLETE: Completed, the request is done + * @MEDIA_REQUEST_STATE_CLEANING: Cleaning, the request is being re-inited + * @MEDIA_REQUEST_STATE_UPDATING: The request is being updated, i.e. + * request objects are being added, + * modified or removed + * @NR_OF_MEDIA_REQUEST_STATE: The number of media request states, used + * internally for sanity check purposes + */ +enum media_request_state { + MEDIA_REQUEST_STATE_IDLE, + MEDIA_REQUEST_STATE_VALIDATING, + MEDIA_REQUEST_STATE_QUEUED, + MEDIA_REQUEST_STATE_COMPLETE, + MEDIA_REQUEST_STATE_CLEANING, + MEDIA_REQUEST_STATE_UPDATING, + NR_OF_MEDIA_REQUEST_STATE, +}; + +struct media_request_object; + +/** + * struct media_request - Media device request + * @mdev: Media device this request belongs to + * @kref: Reference count + * @debug_str: Prefix for debug messages (process name:fd) + * @state: The state of the request + * @updating_count: count the number of request updates that are in progress + * @access_count: count the number of request accesses that are in progress + * @objects: List of @struct media_request_object request objects + * @num_incomplete_objects: The number of incomplete objects in the request + * @poll_wait: Wait queue for poll + * @lock: Serializes access to this struct + */ +struct media_request { + struct media_device *mdev; + struct kref kref; + char debug_str[TASK_COMM_LEN + 11]; + enum media_request_state state; + unsigned int updating_count; + unsigned int access_count; + struct list_head objects; + unsigned int num_incomplete_objects; + wait_queue_head_t poll_wait; + spinlock_t lock; +}; + +#ifdef CONFIG_MEDIA_CONTROLLER + +/** + * media_request_lock_for_access - Lock the request to access its objects + * + * @req: The media request + * + * Use before accessing a completed request. A reference to the request must + * be held during the access. This usually takes place automatically through + * a file handle. Use @media_request_unlock_for_access when done. + */ +static inline int __must_check +media_request_lock_for_access(struct media_request *req) +{ + unsigned long flags; + int ret = -EBUSY; + + spin_lock_irqsave(&req->lock, flags); + if (req->state == MEDIA_REQUEST_STATE_COMPLETE) { + req->access_count++; + ret = 0; + } + spin_unlock_irqrestore(&req->lock, flags); + + return ret; +} + +/** + * media_request_unlock_for_access - Unlock a request previously locked for + * access + * + * @req: The media request + * + * Unlock a request that has previously been locked using + * @media_request_lock_for_access. + */ +static inline void media_request_unlock_for_access(struct media_request *req) +{ + unsigned long flags; + + spin_lock_irqsave(&req->lock, flags); + if (!WARN_ON(!req->access_count)) + req->access_count--; + spin_unlock_irqrestore(&req->lock, flags); +} + +/** + * media_request_lock_for_update - Lock the request for updating its objects + * + * @req: The media request + * + * Use before updating a request, i.e. adding, modifying or removing a request + * object in it. A reference to the request must be held during the update. This + * usually takes place automatically through a file handle. Use + * @media_request_unlock_for_update when done. + */ +static inline int __must_check +media_request_lock_for_update(struct media_request *req) +{ + unsigned long flags; + int ret = 0; + + spin_lock_irqsave(&req->lock, flags); + if (req->state == MEDIA_REQUEST_STATE_IDLE || + req->state == MEDIA_REQUEST_STATE_UPDATING) { + req->state = MEDIA_REQUEST_STATE_UPDATING; + req->updating_count++; + } else { + ret = -EBUSY; + } + spin_unlock_irqrestore(&req->lock, flags); + + return ret; +} + +/** + * media_request_unlock_for_update - Unlock a request previously locked for + * update + * + * @req: The media request + * + * Unlock a request that has previously been locked using + * @media_request_lock_for_update. + */ +static inline void media_request_unlock_for_update(struct media_request *req) +{ + unsigned long flags; + + spin_lock_irqsave(&req->lock, flags); + WARN_ON(req->updating_count <= 0); + if (!--req->updating_count) + req->state = MEDIA_REQUEST_STATE_IDLE; + spin_unlock_irqrestore(&req->lock, flags); +} + +/** + * media_request_get - Get the media request + * + * @req: The media request + * + * Get the media request. + */ +static inline void media_request_get(struct media_request *req) +{ + kref_get(&req->kref); +} + +/** + * media_request_put - Put the media request + * + * @req: The media request + * + * Put the media request. The media request will be released + * when the refcount reaches 0. + */ +void media_request_put(struct media_request *req); + +/** + * media_request_get_by_fd - Get a media request by fd + * + * @mdev: Media device this request belongs to + * @request_fd: The file descriptor of the request + * + * Get the request represented by @request_fd that is owned + * by the media device. + * + * Return a -EBADR error pointer if requests are not supported + * by this driver. Return -EINVAL if the request was not found. + * Return the pointer to the request if found: the caller will + * have to call @media_request_put when it finished using the + * request. + */ +struct media_request * +media_request_get_by_fd(struct media_device *mdev, int request_fd); + +/** + * media_request_alloc - Allocate the media request + * + * @mdev: Media device this request belongs to + * @alloc_fd: Store the request's file descriptor in this int + * + * Allocated the media request and put the fd in @alloc_fd. + */ +int media_request_alloc(struct media_device *mdev, + int *alloc_fd); + +#else + +static inline void media_request_get(struct media_request *req) +{ +} + +static inline void media_request_put(struct media_request *req) +{ +} + +static inline struct media_request * +media_request_get_by_fd(struct media_device *mdev, int request_fd) +{ + return ERR_PTR(-EBADR); +} + +#endif + +/** + * struct media_request_object_ops - Media request object operations + * @prepare: Validate and prepare the request object, optional. + * @unprepare: Unprepare the request object, optional. + * @queue: Queue the request object, optional. + * @unbind: Unbind the request object, optional. + * @release: Release the request object, required. + */ +struct media_request_object_ops { + int (*prepare)(struct media_request_object *object); + void (*unprepare)(struct media_request_object *object); + void (*queue)(struct media_request_object *object); + void (*unbind)(struct media_request_object *object); + void (*release)(struct media_request_object *object); +}; + +/** + * struct media_request_object - An opaque object that belongs to a media + * request + * + * @ops: object's operations + * @priv: object's priv pointer + * @req: the request this object belongs to (can be NULL) + * @list: List entry of the object for @struct media_request + * @kref: Reference count of the object, acquire before releasing req->lock + * @completed: If true, then this object was completed. + * + * An object related to the request. This struct is always embedded in + * another struct that contains the actual data for this request object. + */ +struct media_request_object { + const struct media_request_object_ops *ops; + void *priv; + struct media_request *req; + struct list_head list; + struct kref kref; + bool completed; +}; + +#ifdef CONFIG_MEDIA_CONTROLLER + +/** + * media_request_object_get - Get a media request object + * + * @obj: The object + * + * Get a media request object. + */ +static inline void media_request_object_get(struct media_request_object *obj) +{ + kref_get(&obj->kref); +} + +/** + * media_request_object_put - Put a media request object + * + * @obj: The object + * + * Put a media request object. Once all references are gone, the + * object's memory is released. + */ +void media_request_object_put(struct media_request_object *obj); + +/** + * media_request_object_find - Find an object in a request + * + * @req: The media request + * @ops: Find an object with this ops value + * @priv: Find an object with this priv value + * + * Both @ops and @priv must be non-NULL. + * + * Returns the object pointer or NULL if not found. The caller must + * call media_request_object_put() once it finished using the object. + * + * Since this function needs to walk the list of objects it takes + * the @req->lock spin lock to make this safe. + */ +struct media_request_object * +media_request_object_find(struct media_request *req, + const struct media_request_object_ops *ops, + void *priv); + +/** + * media_request_object_init - Initialise a media request object + * + * @obj: The object + * + * Initialise a media request object. The object will be released using the + * release callback of the ops once it has no references (this function + * initialises references to one). + */ +void media_request_object_init(struct media_request_object *obj); + +/** + * media_request_object_bind - Bind a media request object to a request + * + * @req: The media request + * @ops: The object ops for this object + * @priv: A driver-specific priv pointer associated with this object + * @is_buffer: Set to true if the object a buffer object. + * @obj: The object + * + * Bind this object to the request and set the ops and priv values of + * the object so it can be found later with media_request_object_find(). + * + * Every bound object must be unbound or completed by the kernel at some + * point in time, otherwise the request will never complete. When the + * request is released all completed objects will be unbound by the + * request core code. + * + * Buffer objects will be added to the end of the request's object + * list, non-buffer objects will be added to the front of the list. + * This ensures that all buffer objects are at the end of the list + * and that all non-buffer objects that they depend on are processed + * first. + */ +int media_request_object_bind(struct media_request *req, + const struct media_request_object_ops *ops, + void *priv, bool is_buffer, + struct media_request_object *obj); + +/** + * media_request_object_unbind - Unbind a media request object + * + * @obj: The object + * + * Unbind the media request object from the request. + */ +void media_request_object_unbind(struct media_request_object *obj); + +/** + * media_request_object_complete - Mark the media request object as complete + * + * @obj: The object + * + * Mark the media request object as complete. Only bound objects can + * be completed. + */ +void media_request_object_complete(struct media_request_object *obj); + +#else + +static inline int __must_check +media_request_lock_for_access(struct media_request *req) +{ + return -EINVAL; +} + +static inline void media_request_unlock_for_access(struct media_request *req) +{ +} + +static inline int __must_check +media_request_lock_for_update(struct media_request *req) +{ + return -EINVAL; +} + +static inline void media_request_unlock_for_update(struct media_request *req) +{ +} + +static inline void media_request_object_get(struct media_request_object *obj) +{ +} + +static inline void media_request_object_put(struct media_request_object *obj) +{ +} + +static inline struct media_request_object * +media_request_object_find(struct media_request *req, + const struct media_request_object_ops *ops, + void *priv) +{ + return NULL; +} + +static inline void media_request_object_init(struct media_request_object *obj) +{ + obj->ops = NULL; + obj->req = NULL; +} + +static inline int media_request_object_bind(struct media_request *req, + const struct media_request_object_ops *ops, + void *priv, bool is_buffer, + struct media_request_object *obj) +{ + return 0; +} + +static inline void media_request_object_unbind(struct media_request_object *obj) +{ +} + +static inline void media_request_object_complete(struct media_request_object *obj) +{ +} + +#endif + +#endif |