xref: /openbmc/linux/include/drm/drm_mode_object.h (revision 2a598d0b)
1 /*
2  * Copyright (c) 2016 Intel Corporation
3  *
4  * Permission to use, copy, modify, distribute, and sell this software and its
5  * documentation for any purpose is hereby granted without fee, provided that
6  * the above copyright notice appear in all copies and that both that copyright
7  * notice and this permission notice appear in supporting documentation, and
8  * that the name of the copyright holders not be used in advertising or
9  * publicity pertaining to distribution of the software without specific,
10  * written prior permission.  The copyright holders make no representations
11  * about the suitability of this software for any purpose.  It is provided "as
12  * is" without express or implied warranty.
13  *
14  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20  * OF THIS SOFTWARE.
21  */
22 
23 #ifndef __DRM_MODESET_H__
24 #define __DRM_MODESET_H__
25 
26 #include <linux/kref.h>
27 #include <drm/drm_lease.h>
28 struct drm_object_properties;
29 struct drm_property;
30 struct drm_device;
31 struct drm_file;
32 
33 /**
34  * struct drm_mode_object - base structure for modeset objects
35  * @id: userspace visible identifier
36  * @type: type of the object, one of DRM_MODE_OBJECT\_\*
37  * @properties: properties attached to this object, including values
38  * @refcount: reference count for objects which with dynamic lifetime
39  * @free_cb: free function callback, only set for objects with dynamic lifetime
40  *
41  * Base structure for modeset objects visible to userspace. Objects can be
42  * looked up using drm_mode_object_find(). Besides basic uapi interface
43  * properties like @id and @type it provides two services:
44  *
45  * - It tracks attached properties and their values. This is used by &drm_crtc,
46  *   &drm_plane and &drm_connector. Properties are attached by calling
47  *   drm_object_attach_property() before the object is visible to userspace.
48  *
49  * - For objects with dynamic lifetimes (as indicated by a non-NULL @free_cb) it
50  *   provides reference counting through drm_mode_object_get() and
51  *   drm_mode_object_put(). This is used by &drm_framebuffer, &drm_connector
52  *   and &drm_property_blob. These objects provide specialized reference
53  *   counting wrappers.
54  */
55 struct drm_mode_object {
56 	uint32_t id;
57 	uint32_t type;
58 	struct drm_object_properties *properties;
59 	struct kref refcount;
60 	void (*free_cb)(struct kref *kref);
61 };
62 
63 #define DRM_OBJECT_MAX_PROPERTY 24
64 /**
65  * struct drm_object_properties - property tracking for &drm_mode_object
66  */
67 struct drm_object_properties {
68 	/**
69 	 * @count: number of valid properties, must be less than or equal to
70 	 * DRM_OBJECT_MAX_PROPERTY.
71 	 */
72 
73 	int count;
74 	/**
75 	 * @properties: Array of pointers to &drm_property.
76 	 *
77 	 * NOTE: if we ever start dynamically destroying properties (ie.
78 	 * not at drm_mode_config_cleanup() time), then we'd have to do
79 	 * a better job of detaching property from mode objects to avoid
80 	 * dangling property pointers:
81 	 */
82 	struct drm_property *properties[DRM_OBJECT_MAX_PROPERTY];
83 
84 	/**
85 	 * @values: Array to store the property values, matching @properties. Do
86 	 * not read/write values directly, but use
87 	 * drm_object_property_get_value() and drm_object_property_set_value().
88 	 *
89 	 * Note that atomic drivers do not store mutable properties in this
90 	 * array, but only the decoded values in the corresponding state
91 	 * structure. The decoding is done using the &drm_crtc.atomic_get_property and
92 	 * &drm_crtc.atomic_set_property hooks for &struct drm_crtc. For
93 	 * &struct drm_plane the hooks are &drm_plane_funcs.atomic_get_property and
94 	 * &drm_plane_funcs.atomic_set_property. And for &struct drm_connector
95 	 * the hooks are &drm_connector_funcs.atomic_get_property and
96 	 * &drm_connector_funcs.atomic_set_property .
97 	 *
98 	 * Hence atomic drivers should not use drm_object_property_set_value()
99 	 * and drm_object_property_get_value() on mutable objects, i.e. those
100 	 * without the DRM_MODE_PROP_IMMUTABLE flag set.
101 	 *
102 	 * For atomic drivers the default value of properties is stored in this
103 	 * array, so drm_object_property_get_default_value can be used to
104 	 * retrieve it.
105 	 */
106 	uint64_t values[DRM_OBJECT_MAX_PROPERTY];
107 };
108 
109 /* Avoid boilerplate.  I'm tired of typing. */
110 #define DRM_ENUM_NAME_FN(fnname, list)				\
111 	const char *fnname(int val)				\
112 	{							\
113 		int i;						\
114 		for (i = 0; i < ARRAY_SIZE(list); i++) {	\
115 			if (list[i].type == val)		\
116 				return list[i].name;		\
117 		}						\
118 		return "(unknown)";				\
119 	}
120 
121 struct drm_mode_object *drm_mode_object_find(struct drm_device *dev,
122 					     struct drm_file *file_priv,
123 					     uint32_t id, uint32_t type);
124 void drm_mode_object_get(struct drm_mode_object *obj);
125 void drm_mode_object_put(struct drm_mode_object *obj);
126 
127 int drm_object_property_set_value(struct drm_mode_object *obj,
128 				  struct drm_property *property,
129 				  uint64_t val);
130 int drm_object_property_get_value(struct drm_mode_object *obj,
131 				  struct drm_property *property,
132 				  uint64_t *value);
133 int drm_object_property_get_default_value(struct drm_mode_object *obj,
134 					  struct drm_property *property,
135 					  uint64_t *val);
136 
137 void drm_object_attach_property(struct drm_mode_object *obj,
138 				struct drm_property *property,
139 				uint64_t init_val);
140 
141 bool drm_mode_object_lease_required(uint32_t type);
142 #endif
143