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
33struct drm_encoder;
34
35/**
36 * struct drm_encoder_funcs - encoder controls
37 *
38 * Encoders sit between CRTCs and connectors.
39 */
40struct 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.
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	 * @debugfs_init:
87	 *
88	 * Allows encoders to create encoder-specific debugfs files.
89	 */
90	void (*debugfs_init)(struct drm_encoder *encoder, struct dentry *root);
91};
92
93/**
94 * struct drm_encoder - central DRM encoder structure
95 * @dev: parent DRM device
96 * @head: list management
97 * @base: base KMS object
98 * @name: human readable name, can be overwritten by the driver
99 * @funcs: control functions, can be NULL for simple managed encoders
100 * @helper_private: mid-layer private data
101 *
102 * CRTCs drive pixels to encoders, which convert them into signals
103 * appropriate for a given connector or set of connectors.
104 */
105struct drm_encoder {
106	struct drm_device *dev;
107	struct list_head head;
108
109	struct drm_mode_object base;
110	char *name;
111	/**
112	 * @encoder_type:
113	 *
114	 * One of the DRM_MODE_ENCODER_<foo> types in drm_mode.h. The following
115	 * encoder types are defined thus far:
116	 *
117	 * - DRM_MODE_ENCODER_DAC for VGA and analog on DVI-I/DVI-A.
118	 *
119	 * - DRM_MODE_ENCODER_TMDS for DVI, HDMI and (embedded) DisplayPort.
120	 *
121	 * - DRM_MODE_ENCODER_LVDS for display panels, or in general any panel
122	 *   with a proprietary parallel connector.
123	 *
124	 * - DRM_MODE_ENCODER_TVDAC for TV output (Composite, S-Video,
125	 *   Component, SCART).
126	 *
127	 * - DRM_MODE_ENCODER_VIRTUAL for virtual machine displays
128	 *
129	 * - DRM_MODE_ENCODER_DSI for panels connected using the DSI serial bus.
130	 *
131	 * - DRM_MODE_ENCODER_DPI for panels connected using the DPI parallel
132	 *   bus.
133	 *
134	 * - DRM_MODE_ENCODER_DPMST for special fake encoders used to allow
135	 *   mutliple DP MST streams to share one physical encoder.
136	 */
137	int encoder_type;
138
139	/**
140	 * @index: Position inside the mode_config.list, can be used as an array
141	 * index. It is invariant over the lifetime of the encoder.
142	 */
143	unsigned index;
144
145	/**
146	 * @possible_crtcs: Bitmask of potential CRTC bindings, using
147	 * drm_crtc_index() as the index into the bitfield. The driver must set
148	 * the bits for all &drm_crtc objects this encoder can be connected to
149	 * before calling drm_dev_register().
150	 *
151	 * You will get a WARN if you get this wrong in the driver.
152	 *
153	 * Note that since CRTC objects can't be hotplugged the assigned indices
154	 * are stable and hence known before registering all objects.
155	 */
156	uint32_t possible_crtcs;
157
158	/**
159	 * @possible_clones: Bitmask of potential sibling encoders for cloning,
160	 * using drm_encoder_index() as the index into the bitfield. The driver
161	 * must set the bits for all &drm_encoder objects which can clone a
162	 * &drm_crtc together with this encoder before calling
163	 * drm_dev_register(). Drivers should set the bit representing the
164	 * encoder itself, too. Cloning bits should be set such that when two
165	 * encoders can be used in a cloned configuration, they both should have
166	 * each another bits set.
167	 *
168	 * As an exception to the above rule if the driver doesn't implement
169	 * any cloning it can leave @possible_clones set to 0. The core will
170	 * automagically fix this up by setting the bit for the encoder itself.
171	 *
172	 * You will get a WARN if you get this wrong in the driver.
173	 *
174	 * Note that since encoder objects can't be hotplugged the assigned indices
175	 * are stable and hence known before registering all objects.
176	 */
177	uint32_t possible_clones;
178
179	/**
180	 * @crtc: Currently bound CRTC, only really meaningful for non-atomic
181	 * drivers.  Atomic drivers should instead check
182	 * &drm_connector_state.crtc.
183	 */
184	struct drm_crtc *crtc;
185
186	/**
187	 * @bridge_chain: Bridges attached to this encoder. Drivers shall not
188	 * access this field directly.
189	 */
190	struct list_head bridge_chain;
191
192	const struct drm_encoder_funcs *funcs;
193	const struct drm_encoder_helper_funcs *helper_private;
194
195	/**
196	 * @debugfs_entry:
197	 *
198	 * Debugfs directory for this CRTC.
199	 */
200	struct dentry *debugfs_entry;
201};
202
203#define obj_to_encoder(x) container_of(x, struct drm_encoder, base)
204
205__printf(5, 6)
206int drm_encoder_init(struct drm_device *dev,
207		     struct drm_encoder *encoder,
208		     const struct drm_encoder_funcs *funcs,
209		     int encoder_type, const char *name, ...);
210
211__printf(5, 6)
212int drmm_encoder_init(struct drm_device *dev,
213		      struct drm_encoder *encoder,
214		      const struct drm_encoder_funcs *funcs,
215		      int encoder_type, const char *name, ...);
216
217__printf(6, 7)
218void *__drmm_encoder_alloc(struct drm_device *dev,
219			   size_t size, size_t offset,
220			   const struct drm_encoder_funcs *funcs,
221			   int encoder_type,
222			   const char *name, ...);
223
224/**
225 * drmm_encoder_alloc - Allocate and initialize an encoder
226 * @dev: drm device
227 * @type: the type of the struct which contains struct &drm_encoder
228 * @member: the name of the &drm_encoder within @type
229 * @funcs: callbacks for this encoder (optional)
230 * @encoder_type: user visible type of the encoder
231 * @name: printf style format string for the encoder name, or NULL for default name
232 *
233 * Allocates and initializes an encoder. Encoder should be subclassed as part of
234 * driver encoder objects. Cleanup is automatically handled through registering
235 * drm_encoder_cleanup() with drmm_add_action().
236 *
237 * The @drm_encoder_funcs.destroy hook must be NULL.
238 *
239 * Returns:
240 * Pointer to new encoder, or ERR_PTR on failure.
241 */
242#define drmm_encoder_alloc(dev, type, member, funcs, encoder_type, name, ...) \
243	((type *)__drmm_encoder_alloc(dev, sizeof(type), \
244				      offsetof(type, member), funcs, \
245				      encoder_type, name, ##__VA_ARGS__))
246
247/**
248 * drmm_plain_encoder_alloc - Allocate and initialize an encoder
249 * @dev: drm device
250 * @funcs: callbacks for this encoder (optional)
251 * @encoder_type: user visible type of the encoder
252 * @name: printf style format string for the encoder name, or NULL for default name
253 *
254 * This is a simplified version of drmm_encoder_alloc(), which only allocates
255 * and returns a struct drm_encoder instance, with no subclassing.
256 *
257 * Returns:
258 * Pointer to the new drm_encoder struct, or ERR_PTR on failure.
259 */
260#define drmm_plain_encoder_alloc(dev, funcs, encoder_type, name, ...) \
261	((struct drm_encoder *) \
262	 __drmm_encoder_alloc(dev, sizeof(struct drm_encoder), \
263			      0, funcs, encoder_type, name, ##__VA_ARGS__))
264
265/**
266 * drm_encoder_index - find the index of a registered encoder
267 * @encoder: encoder to find index for
268 *
269 * Given a registered encoder, return the index of that encoder within a DRM
270 * device's list of encoders.
271 */
272static inline unsigned int drm_encoder_index(const struct drm_encoder *encoder)
273{
274	return encoder->index;
275}
276
277/**
278 * drm_encoder_mask - find the mask of a registered encoder
279 * @encoder: encoder to find mask for
280 *
281 * Given a registered encoder, return the mask bit of that encoder for an
282 * encoder's possible_clones field.
283 */
284static inline u32 drm_encoder_mask(const struct drm_encoder *encoder)
285{
286	return 1 << drm_encoder_index(encoder);
287}
288
289/**
290 * drm_encoder_crtc_ok - can a given crtc drive a given encoder?
291 * @encoder: encoder to test
292 * @crtc: crtc to test
293 *
294 * Returns false if @encoder can't be driven by @crtc, true otherwise.
295 */
296static inline bool drm_encoder_crtc_ok(struct drm_encoder *encoder,
297				       struct drm_crtc *crtc)
298{
299	return !!(encoder->possible_crtcs & drm_crtc_mask(crtc));
300}
301
302/**
303 * drm_encoder_find - find a &drm_encoder
304 * @dev: DRM device
305 * @file_priv: drm file to check for lease against.
306 * @id: encoder id
307 *
308 * Returns the encoder with @id, NULL if it doesn't exist. Simple wrapper around
309 * drm_mode_object_find().
310 */
311static inline struct drm_encoder *drm_encoder_find(struct drm_device *dev,
312						   struct drm_file *file_priv,
313						   uint32_t id)
314{
315	struct drm_mode_object *mo;
316
317	mo = drm_mode_object_find(dev, file_priv, id, DRM_MODE_OBJECT_ENCODER);
318
319	return mo ? obj_to_encoder(mo) : NULL;
320}
321
322void drm_encoder_cleanup(struct drm_encoder *encoder);
323
324/**
325 * drm_for_each_encoder_mask - iterate over encoders specified by bitmask
326 * @encoder: the loop cursor
327 * @dev: the DRM device
328 * @encoder_mask: bitmask of encoder indices
329 *
330 * Iterate over all encoders specified by bitmask.
331 */
332#define drm_for_each_encoder_mask(encoder, dev, encoder_mask) \
333	list_for_each_entry((encoder), &(dev)->mode_config.encoder_list, head) \
334		for_each_if ((encoder_mask) & drm_encoder_mask(encoder))
335
336/**
337 * drm_for_each_encoder - iterate over all encoders
338 * @encoder: the loop cursor
339 * @dev: the DRM device
340 *
341 * Iterate over all encoders of @dev.
342 */
343#define drm_for_each_encoder(encoder, dev) \
344	list_for_each_entry(encoder, &(dev)->mode_config.encoder_list, head)
345
346#endif
347