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Diffstat (limited to 'include/media/media-dev-allocator.h')
| -rw-r--r-- | include/media/media-dev-allocator.h | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/include/media/media-dev-allocator.h b/include/media/media-dev-allocator.h new file mode 100644 index 0000000000..2ab54d426c --- /dev/null +++ b/include/media/media-dev-allocator.h @@ -0,0 +1,63 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * media-dev-allocator.h - Media Controller Device Allocator API + * + * Copyright (c) 2019 Shuah Khan <shuah@kernel.org> + * + * Credits: Suggested by Laurent Pinchart <laurent.pinchart@ideasonboard.com> + */ + +/* + * This file adds a global ref-counted Media Controller Device Instance API. + * A system wide global media device list is managed and each media device + * includes a kref count. The last put on the media device releases the media + * device instance. + */ + +#ifndef _MEDIA_DEV_ALLOCATOR_H +#define _MEDIA_DEV_ALLOCATOR_H + +struct usb_device; + +#if defined(CONFIG_MEDIA_CONTROLLER) && IS_ENABLED(CONFIG_USB) +/** + * media_device_usb_allocate() - Allocate and return struct &media device + * + * @udev: struct &usb_device pointer + * @module_name: should be filled with %KBUILD_MODNAME + * @owner: struct module pointer %THIS_MODULE for the driver. + * %THIS_MODULE is null for a built-in driver. + * It is safe even when %THIS_MODULE is null. + * + * This interface should be called to allocate a Media Device when multiple + * drivers share usb_device and the media device. This interface allocates + * &media_device structure and calls media_device_usb_init() to initialize + * it. + * + */ +struct media_device *media_device_usb_allocate(struct usb_device *udev, + const char *module_name, + struct module *owner); +/** + * media_device_delete() - Release media device. Calls kref_put(). + * + * @mdev: struct &media_device pointer + * @module_name: should be filled with %KBUILD_MODNAME + * @owner: struct module pointer %THIS_MODULE for the driver. + * %THIS_MODULE is null for a built-in driver. + * It is safe even when %THIS_MODULE is null. + * + * This interface should be called to put Media Device Instance kref. + */ +void media_device_delete(struct media_device *mdev, const char *module_name, + struct module *owner); +#else +static inline struct media_device *media_device_usb_allocate( + struct usb_device *udev, const char *module_name, + struct module *owner) + { return NULL; } +static inline void media_device_delete( + struct media_device *mdev, const char *module_name, + struct module *owner) { } +#endif /* CONFIG_MEDIA_CONTROLLER && CONFIG_USB */ +#endif /* _MEDIA_DEV_ALLOCATOR_H */ |