xref: /dragonfly/sys/dev/drm/include/drm/drm_encoder.h (revision 1a05b9d1)
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_ENCODER_H__
24 #define __DRM_ENCODER_H__
25 
26 #include <linux/list.h>
27 #include <linux/ctype.h>
28 #include <drm/drm_mode_object.h>
29 
30 /**
31  * struct drm_encoder_funcs - encoder controls
32  *
33  * Encoders sit between CRTCs and connectors.
34  */
35 struct drm_encoder_funcs {
36 	/**
37 	 * @reset:
38 	 *
39 	 * Reset encoder hardware and software state to off. This function isn't
40 	 * called by the core directly, only through drm_mode_config_reset().
41 	 * It's not a helper hook only for historical reasons.
42 	 */
43 	void (*reset)(struct drm_encoder *encoder);
44 
45 	/**
46 	 * @destroy:
47 	 *
48 	 * Clean up encoder resources. This is only called at driver unload time
49 	 * through drm_mode_config_cleanup() since an encoder cannot be
50 	 * hotplugged in DRM.
51 	 */
52 	void (*destroy)(struct drm_encoder *encoder);
53 
54 	/**
55 	 * @late_register:
56 	 *
57 	 * This optional hook can be used to register additional userspace
58 	 * interfaces attached to the encoder like debugfs interfaces.
59 	 * It is called late in the driver load sequence from drm_dev_register().
60 	 * Everything added from this callback should be unregistered in
61 	 * the early_unregister callback.
62 	 *
63 	 * Returns:
64 	 *
65 	 * 0 on success, or a negative error code on failure.
66 	 */
67 	int (*late_register)(struct drm_encoder *encoder);
68 
69 	/**
70 	 * @early_unregister:
71 	 *
72 	 * This optional hook should be used to unregister the additional
73 	 * userspace interfaces attached to the encoder from
74 	 * late_unregister(). It is called from drm_dev_unregister(),
75 	 * early in the driver unload sequence to disable userspace access
76 	 * before data structures are torndown.
77 	 */
78 	void (*early_unregister)(struct drm_encoder *encoder);
79 };
80 
81 /**
82  * struct drm_encoder - central DRM encoder structure
83  * @dev: parent DRM device
84  * @head: list management
85  * @base: base KMS object
86  * @name: human readable name, can be overwritten by the driver
87  * @crtc: currently bound CRTC
88  * @bridge: bridge associated to the encoder
89  * @funcs: control functions
90  * @helper_private: mid-layer private data
91  *
92  * CRTCs drive pixels to encoders, which convert them into signals
93  * appropriate for a given connector or set of connectors.
94  */
95 struct drm_encoder {
96 	struct drm_device *dev;
97 	struct list_head head;
98 
99 	struct drm_mode_object base;
100 	char *name;
101 	/**
102 	 * @encoder_type:
103 	 *
104 	 * One of the DRM_MODE_ENCODER_<foo> types in drm_mode.h. The following
105 	 * encoder types are defined thus far:
106 	 *
107 	 * - DRM_MODE_ENCODER_DAC for VGA and analog on DVI-I/DVI-A.
108 	 *
109 	 * - DRM_MODE_ENCODER_TMDS for DVI, HDMI and (embedded) DisplayPort.
110 	 *
111 	 * - DRM_MODE_ENCODER_LVDS for display panels, or in general any panel
112 	 *   with a proprietary parallel connector.
113 	 *
114 	 * - DRM_MODE_ENCODER_TVDAC for TV output (Composite, S-Video,
115 	 *   Component, SCART).
116 	 *
117 	 * - DRM_MODE_ENCODER_VIRTUAL for virtual machine displays
118 	 *
119 	 * - DRM_MODE_ENCODER_DSI for panels connected using the DSI serial bus.
120 	 *
121 	 * - DRM_MODE_ENCODER_DPI for panels connected using the DPI parallel
122 	 *   bus.
123 	 *
124 	 * - DRM_MODE_ENCODER_DPMST for special fake encoders used to allow
125 	 *   mutliple DP MST streams to share one physical encoder.
126 	 */
127 	int encoder_type;
128 
129 	/**
130 	 * @index: Position inside the mode_config.list, can be used as an array
131 	 * index. It is invariant over the lifetime of the encoder.
132 	 */
133 	unsigned index;
134 
135 	/**
136 	 * @possible_crtcs: Bitmask of potential CRTC bindings, using
137 	 * drm_crtc_index() as the index into the bitfield. The driver must set
138 	 * the bits for all &drm_crtc objects this encoder can be connected to
139 	 * before calling drm_encoder_init().
140 	 *
141 	 * In reality almost every driver gets this wrong.
142 	 *
143 	 * Note that since CRTC objects can't be hotplugged the assigned indices
144 	 * are stable and hence known before registering all objects.
145 	 */
146 	uint32_t possible_crtcs;
147 
148 	/**
149 	 * @possible_clones: Bitmask of potential sibling encoders for cloning,
150 	 * using drm_encoder_index() as the index into the bitfield. The driver
151 	 * must set the bits for all &drm_encoder objects which can clone a
152 	 * &drm_crtc together with this encoder before calling
153 	 * drm_encoder_init(). Drivers should set the bit representing the
154 	 * encoder itself, too. Cloning bits should be set such that when two
155 	 * encoders can be used in a cloned configuration, they both should have
156 	 * each another bits set.
157 	 *
158 	 * In reality almost every driver gets this wrong.
159 	 *
160 	 * Note that since encoder objects can't be hotplugged the assigned indices
161 	 * are stable and hence known before registering all objects.
162 	 */
163 	uint32_t possible_clones;
164 
165 	struct drm_crtc *crtc;
166 	struct drm_bridge *bridge;
167 	const struct drm_encoder_funcs *funcs;
168 	const struct drm_encoder_helper_funcs *helper_private;
169 };
170 
171 #define obj_to_encoder(x) container_of(x, struct drm_encoder, base)
172 
173 int drm_encoder_init(struct drm_device *dev,
174 		     struct drm_encoder *encoder,
175 		     const struct drm_encoder_funcs *funcs,
176 		     int encoder_type, const char *name, ...);
177 
178 /**
179  * drm_encoder_index - find the index of a registered encoder
180  * @encoder: encoder to find index for
181  *
182  * Given a registered encoder, return the index of that encoder within a DRM
183  * device's list of encoders.
184  */
185 static inline unsigned int drm_encoder_index(struct drm_encoder *encoder)
186 {
187 	return encoder->index;
188 }
189 
190 /* FIXME: We have an include file mess still, drm_crtc.h needs untangling. */
191 static inline uint32_t drm_crtc_mask(const struct drm_crtc *crtc);
192 
193 /**
194  * drm_encoder_crtc_ok - can a given crtc drive a given encoder?
195  * @encoder: encoder to test
196  * @crtc: crtc to test
197  *
198  * Returns false if @encoder can't be driven by @crtc, true otherwise.
199  */
200 static inline bool drm_encoder_crtc_ok(struct drm_encoder *encoder,
201 				       struct drm_crtc *crtc)
202 {
203 	return !!(encoder->possible_crtcs & drm_crtc_mask(crtc));
204 }
205 
206 /**
207  * drm_encoder_find - find a &drm_encoder
208  * @dev: DRM device
209  * @id: encoder id
210  *
211  * Returns the encoder with @id, NULL if it doesn't exist. Simple wrapper around
212  * drm_mode_object_find().
213  */
214 static inline struct drm_encoder *drm_encoder_find(struct drm_device *dev,
215 						   uint32_t id)
216 {
217 	struct drm_mode_object *mo;
218 
219 	mo = drm_mode_object_find(dev, id, DRM_MODE_OBJECT_ENCODER);
220 
221 	return mo ? obj_to_encoder(mo) : NULL;
222 }
223 
224 void drm_encoder_cleanup(struct drm_encoder *encoder);
225 
226 /**
227  * drm_for_each_encoder_mask - iterate over encoders specified by bitmask
228  * @encoder: the loop cursor
229  * @dev: the DRM device
230  * @encoder_mask: bitmask of encoder indices
231  *
232  * Iterate over all encoders specified by bitmask.
233  */
234 #define drm_for_each_encoder_mask(encoder, dev, encoder_mask) \
235 	list_for_each_entry((encoder), &(dev)->mode_config.encoder_list, head) \
236 		for_each_if ((encoder_mask) & (1 << drm_encoder_index(encoder)))
237 
238 /**
239  * drm_for_each_encoder - iterate over all encoders
240  * @encoder: the loop cursor
241  * @dev: the DRM device
242  *
243  * Iterate over all encoders of @dev.
244  */
245 #define drm_for_each_encoder(encoder, dev) \
246 	list_for_each_entry(encoder, &(dev)->mode_config.encoder_list, head)
247 
248 #endif
249