1/* SPDX-License-Identifier: MIT */
2/*
3 * Copyright (C) 2020 Red Hat, Inc.
4 *
5 * Authors:
6 * Hans de Goede <hdegoede@redhat.com>
7 */
8
9#ifndef __DRM_PRIVACY_SCREEN_DRIVER_H__
10#define __DRM_PRIVACY_SCREEN_DRIVER_H__
11
12#include <linux/device.h>
13#include <linux/list.h>
14#include <linux/mutex.h>
15#include <drm/drm_connector.h>
16
17struct drm_privacy_screen;
18
19/**
20 * struct drm_privacy_screen_ops - drm_privacy_screen operations
21 *
22 * Defines the operations which the privacy-screen class code may call.
23 * These functions should be implemented by the privacy-screen driver.
24 */
25struct drm_privacy_screen_ops {
26	/**
27	 * @set_sw_state: Called to request a change of the privacy-screen
28	 * state. The privacy-screen class code contains a check to avoid this
29	 * getting called when the hw_state reports the state is locked.
30	 * It is the driver's responsibility to update sw_state and hw_state.
31	 * This is always called with the drm_privacy_screen's lock held.
32	 */
33	int (*set_sw_state)(struct drm_privacy_screen *priv,
34			    enum drm_privacy_screen_status sw_state);
35	/**
36	 * @get_hw_state: Called to request that the driver gets the current
37	 * privacy-screen state from the hardware and then updates sw_state and
38	 * hw_state accordingly. This will be called by the core just before
39	 * the privacy-screen is registered in sysfs.
40	 */
41	void (*get_hw_state)(struct drm_privacy_screen *priv);
42};
43
44/**
45 * struct drm_privacy_screen - central privacy-screen structure
46 *
47 * Central privacy-screen structure, this contains the struct device used
48 * to register the screen in sysfs, the screen's state, ops, etc.
49 */
50struct drm_privacy_screen {
51	/** @dev: device used to register the privacy-screen in sysfs. */
52	struct device dev;
53	/** @lock: mutex protection all fields in this struct. */
54	struct mutex lock;
55	/** @list: privacy-screen devices list list-entry. */
56	struct list_head list;
57	/** @notifier_head: privacy-screen notifier head. */
58	struct blocking_notifier_head notifier_head;
59	/**
60	 * @ops: &struct drm_privacy_screen_ops for this privacy-screen.
61	 * This is NULL if the driver has unregistered the privacy-screen.
62	 */
63	const struct drm_privacy_screen_ops *ops;
64	/**
65	 * @sw_state: The privacy-screen's software state, see
66	 * :ref:`Standard Connector Properties<standard_connector_properties>`
67	 * for more info.
68	 */
69	enum drm_privacy_screen_status sw_state;
70	/**
71	 * @hw_state: The privacy-screen's hardware state, see
72	 * :ref:`Standard Connector Properties<standard_connector_properties>`
73	 * for more info.
74	 */
75	enum drm_privacy_screen_status hw_state;
76	/**
77	 * @drvdata: Private data owned by the privacy screen provider
78	 */
79	void *drvdata;
80};
81
82static inline
83void *drm_privacy_screen_get_drvdata(struct drm_privacy_screen *priv)
84{
85	return priv->drvdata;
86}
87
88struct drm_privacy_screen *drm_privacy_screen_register(
89	struct device *parent, const struct drm_privacy_screen_ops *ops,
90	void *data);
91void drm_privacy_screen_unregister(struct drm_privacy_screen *priv);
92
93void drm_privacy_screen_call_notifier_chain(struct drm_privacy_screen *priv);
94
95#endif
96