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_crtc.h>
29 #include <drm/drm_mode.h>
30 #include <drm/drm_mode_object.h>
31 #include <drm/drm_util.h>
32
33 struct drm_encoder;
34
35 /**
36 * struct drm_encoder_funcs - encoder controls
37 *
38 * Encoders sit between CRTCs and connectors.
39 */
40 struct drm_encoder_funcs {
41 /**
42 * @reset:
43 *
44 * Reset encoder hardware and software state to off. This function isn't
45 * called by the core directly, only through drm_mode_config_reset().
46 * It's not a helper hook only for historical reasons.
47 */
48 void (*reset)(struct drm_encoder *encoder);
49
50 /**
51 * @destroy:
52 *
53 * Clean up encoder resources. This is only called at driver unload time
54 * through drm_mode_config_cleanup() since an encoder cannot be
55 * hotplugged in DRM.
56 */
57 void (*destroy)(struct drm_encoder *encoder);
58
59 /**
60 * @late_register:
61 *
62 * This optional hook can be used to register additional userspace
63 * interfaces attached to the encoder like debugfs interfaces.
64 * It is called late in the driver load sequence from drm_dev_register().
65 * Everything added from this callback should be unregistered in
66 * the early_unregister callback.
67 *
68 * Returns:
69 *
70 * 0 on success, or a negative error code on failure.
71 */
72 int (*late_register)(struct drm_encoder *encoder);
73
74 /**
75 * @early_unregister:
76 *
77 * This optional hook should be used to unregister the additional
78 * userspace interfaces attached to the encoder from
79 * @late_register. It is called from drm_dev_unregister(),
80 * early in the driver unload sequence to disable userspace access
81 * before data structures are torndown.
82 */
83 void (*early_unregister)(struct drm_encoder *encoder);
84 };
85
86 /**
87 * struct drm_encoder - central DRM encoder structure
88 * @dev: parent DRM device
89 * @head: list management
90 * @base: base KMS object
91 * @name: human readable name, can be overwritten by the driver
92 * @bridge: bridge associated to the encoder
93 * @funcs: control functions
94 * @helper_private: mid-layer private data
95 *
96 * CRTCs drive pixels to encoders, which convert them into signals
97 * appropriate for a given connector or set of connectors.
98 */
99 struct drm_encoder {
100 struct drm_device *dev;
101 struct list_head head;
102
103 struct drm_mode_object base;
104 char *name;
105 /**
106 * @encoder_type:
107 *
108 * One of the DRM_MODE_ENCODER_<foo> types in drm_mode.h. The following
109 * encoder types are defined thus far:
110 *
111 * - DRM_MODE_ENCODER_DAC for VGA and analog on DVI-I/DVI-A.
112 *
113 * - DRM_MODE_ENCODER_TMDS for DVI, HDMI and (embedded) DisplayPort.
114 *
115 * - DRM_MODE_ENCODER_LVDS for display panels, or in general any panel
116 * with a proprietary parallel connector.
117 *
118 * - DRM_MODE_ENCODER_TVDAC for TV output (Composite, S-Video,
119 * Component, SCART).
120 *
121 * - DRM_MODE_ENCODER_VIRTUAL for virtual machine displays
122 *
123 * - DRM_MODE_ENCODER_DSI for panels connected using the DSI serial bus.
124 *
125 * - DRM_MODE_ENCODER_DPI for panels connected using the DPI parallel
126 * bus.
127 *
128 * - DRM_MODE_ENCODER_DPMST for special fake encoders used to allow
129 * mutliple DP MST streams to share one physical encoder.
130 */
131 int encoder_type;
132
133 /**
134 * @index: Position inside the mode_config.list, can be used as an array
135 * index. It is invariant over the lifetime of the encoder.
136 */
137 unsigned index;
138
139 /**
140 * @possible_crtcs: Bitmask of potential CRTC bindings, using
141 * drm_crtc_index() as the index into the bitfield. The driver must set
142 * the bits for all &drm_crtc objects this encoder can be connected to
143 * before calling drm_encoder_init().
144 *
145 * In reality almost every driver gets this wrong.
146 *
147 * Note that since CRTC objects can't be hotplugged the assigned indices
148 * are stable and hence known before registering all objects.
149 */
150 uint32_t possible_crtcs;
151
152 /**
153 * @possible_clones: Bitmask of potential sibling encoders for cloning,
154 * using drm_encoder_index() as the index into the bitfield. The driver
155 * must set the bits for all &drm_encoder objects which can clone a
156 * &drm_crtc together with this encoder before calling
157 * drm_encoder_init(). Drivers should set the bit representing the
158 * encoder itself, too. Cloning bits should be set such that when two
159 * encoders can be used in a cloned configuration, they both should have
160 * each another bits set.
161 *
162 * In reality almost every driver gets this wrong.
163 *
164 * Note that since encoder objects can't be hotplugged the assigned indices
165 * are stable and hence known before registering all objects.
166 */
167 uint32_t possible_clones;
168
169 /**
170 * @crtc: Currently bound CRTC, only really meaningful for non-atomic
171 * drivers. Atomic drivers should instead check
172 * &drm_connector_state.crtc.
173 */
174 struct drm_crtc *crtc;
175 struct drm_bridge *bridge;
176 const struct drm_encoder_funcs *funcs;
177 const struct drm_encoder_helper_funcs *helper_private;
178 };
179
180 #define obj_to_encoder(x) container_of(x, struct drm_encoder, base)
181
182 __printf(5, 6)
183 int drm_encoder_init(struct drm_device *dev,
184 struct drm_encoder *encoder,
185 const struct drm_encoder_funcs *funcs,
186 int encoder_type, const char *name, ...);
187
188 /**
189 * drm_encoder_index - find the index of a registered encoder
190 * @encoder: encoder to find index for
191 *
192 * Given a registered encoder, return the index of that encoder within a DRM
193 * device's list of encoders.
194 */
195 static inline unsigned int drm_encoder_index(const struct drm_encoder *encoder)
196 {
197 return encoder->index;
198 }
199
200 /**
201 * drm_encoder_mask - find the mask of a registered ENCODER
202 * @encoder: encoder to find mask for
203 *
204 * Given a registered encoder, return the mask bit of that encoder for an
205 * encoder's possible_clones field.
206 */
207 static inline u32 drm_encoder_mask(const struct drm_encoder *encoder)
208 {
209 return 1 << drm_encoder_index(encoder);
210 }
211
212 /**
213 * drm_encoder_crtc_ok - can a given crtc drive a given encoder?
214 * @encoder: encoder to test
215 * @crtc: crtc to test
216 *
217 * Returns false if @encoder can't be driven by @crtc, true otherwise.
218 */
219 static inline bool drm_encoder_crtc_ok(struct drm_encoder *encoder,
220 struct drm_crtc *crtc)
221 {
222 return !!(encoder->possible_crtcs & drm_crtc_mask(crtc));
223 }
224
225 /**
226 * drm_encoder_find - find a &drm_encoder
227 * @dev: DRM device
228 * @file_priv: drm file to check for lease against.
229 * @id: encoder id
230 *
231 * Returns the encoder with @id, NULL if it doesn't exist. Simple wrapper around
232 * drm_mode_object_find().
233 */
234 static inline struct drm_encoder *drm_encoder_find(struct drm_device *dev,
235 struct drm_file *file_priv,
236 uint32_t id)
237 {
238 struct drm_mode_object *mo;
239
240 mo = drm_mode_object_find(dev, file_priv, id, DRM_MODE_OBJECT_ENCODER);
241
242 return mo ? obj_to_encoder(mo) : NULL;
243 }
244
245 void drm_encoder_cleanup(struct drm_encoder *encoder);
246
247 /**
248 * drm_for_each_encoder_mask - iterate over encoders specified by bitmask
249 * @encoder: the loop cursor
250 * @dev: the DRM device
251 * @encoder_mask: bitmask of encoder indices
252 *
253 * Iterate over all encoders specified by bitmask.
254 */
255 #define drm_for_each_encoder_mask(encoder, dev, encoder_mask) \
256 list_for_each_entry((encoder), &(dev)->mode_config.encoder_list, head) \
257 for_each_if ((encoder_mask) & drm_encoder_mask(encoder))
258
259 /**
260 * drm_for_each_encoder - iterate over all encoders
261 * @encoder: the loop cursor
262 * @dev: the DRM device
263 *
264 * Iterate over all encoders of @dev.
265 */
266 #define drm_for_each_encoder(encoder, dev) \
267 list_for_each_entry(encoder, &(dev)->mode_config.encoder_list, head)
268
269 #endif