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