1 | /* SPDX-License-Identifier: GPL-2.0+ */ |
2 | /* |
3 | * media-dev-allocator.h - Media Controller Device Allocator API |
4 | * |
5 | * Copyright (c) 2019 Shuah Khan <shuah@kernel.org> |
6 | * |
7 | * Credits: Suggested by Laurent Pinchart <laurent.pinchart@ideasonboard.com> |
8 | */ |
9 | |
10 | /* |
11 | * This file adds a global ref-counted Media Controller Device Instance API. |
12 | * A system wide global media device list is managed and each media device |
13 | * includes a kref count. The last put on the media device releases the media |
14 | * device instance. |
15 | */ |
16 | |
17 | #ifndef _MEDIA_DEV_ALLOCATOR_H |
18 | #define _MEDIA_DEV_ALLOCATOR_H |
19 | |
20 | struct usb_device; |
21 | |
22 | #if defined(CONFIG_MEDIA_CONTROLLER) && IS_ENABLED(CONFIG_USB) |
23 | /** |
24 | * media_device_usb_allocate() - Allocate and return struct &media device |
25 | * |
26 | * @udev: struct &usb_device pointer |
27 | * @module_name: should be filled with %KBUILD_MODNAME |
28 | * @owner: struct module pointer %THIS_MODULE for the driver. |
29 | * %THIS_MODULE is null for a built-in driver. |
30 | * It is safe even when %THIS_MODULE is null. |
31 | * |
32 | * This interface should be called to allocate a Media Device when multiple |
33 | * drivers share usb_device and the media device. This interface allocates |
34 | * &media_device structure and calls media_device_usb_init() to initialize |
35 | * it. |
36 | * |
37 | */ |
38 | struct media_device *media_device_usb_allocate(struct usb_device *udev, |
39 | const char *module_name, |
40 | struct module *owner); |
41 | /** |
42 | * media_device_delete() - Release media device. Calls kref_put(). |
43 | * |
44 | * @mdev: struct &media_device pointer |
45 | * @module_name: should be filled with %KBUILD_MODNAME |
46 | * @owner: struct module pointer %THIS_MODULE for the driver. |
47 | * %THIS_MODULE is null for a built-in driver. |
48 | * It is safe even when %THIS_MODULE is null. |
49 | * |
50 | * This interface should be called to put Media Device Instance kref. |
51 | */ |
52 | void media_device_delete(struct media_device *mdev, const char *module_name, |
53 | struct module *owner); |
54 | #else |
55 | static inline struct media_device *media_device_usb_allocate( |
56 | struct usb_device *udev, const char *module_name, |
57 | struct module *owner) |
58 | { return NULL; } |
59 | static inline void media_device_delete( |
60 | struct media_device *mdev, const char *module_name, |
61 | struct module *owner) { } |
62 | #endif /* CONFIG_MEDIA_CONTROLLER && CONFIG_USB */ |
63 | #endif /* _MEDIA_DEV_ALLOCATOR_H */ |
64 | |