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