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v5.4
  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_BRIDGE_H__
 24#define __DRM_BRIDGE_H__
 25
 26#include <linux/list.h>
 27#include <linux/ctype.h>
 
 
 
 
 
 28#include <drm/drm_mode_object.h>
 29#include <drm/drm_modes.h>
 30
 
 
 31struct drm_bridge;
 32struct drm_bridge_timings;
 
 
 
 33struct drm_panel;
 
 
 
 
 
 
 
 
 
 
 
 
 
 34
 35/**
 36 * struct drm_bridge_funcs - drm_bridge control functions
 37 */
 38struct drm_bridge_funcs {
 39	/**
 40	 * @attach:
 41	 *
 42	 * This callback is invoked whenever our bridge is being attached to a
 43	 * &drm_encoder.
 
 44	 *
 45	 * The attach callback is optional.
 46	 *
 47	 * RETURNS:
 48	 *
 49	 * Zero on success, error code on failure.
 50	 */
 51	int (*attach)(struct drm_bridge *bridge);
 
 52
 53	/**
 54	 * @detach:
 55	 *
 56	 * This callback is invoked whenever our bridge is being detached from a
 57	 * &drm_encoder.
 58	 *
 59	 * The detach callback is optional.
 60	 */
 61	void (*detach)(struct drm_bridge *bridge);
 62
 63	/**
 64	 * @mode_valid:
 65	 *
 66	 * This callback is used to check if a specific mode is valid in this
 67	 * bridge. This should be implemented if the bridge has some sort of
 68	 * restriction in the modes it can display. For example, a given bridge
 69	 * may be responsible to set a clock value. If the clock can not
 70	 * produce all the values for the available modes then this callback
 71	 * can be used to restrict the number of modes to only the ones that
 72	 * can be displayed.
 73	 *
 74	 * This hook is used by the probe helpers to filter the mode list in
 75	 * drm_helper_probe_single_connector_modes(), and it is used by the
 76	 * atomic helpers to validate modes supplied by userspace in
 77	 * drm_atomic_helper_check_modeset().
 78	 *
 79	 * This function is optional.
 80	 *
 81	 * NOTE:
 82	 *
 83	 * Since this function is both called from the check phase of an atomic
 84	 * commit, and the mode validation in the probe paths it is not allowed
 85	 * to look at anything else but the passed-in mode, and validate it
 86	 * against configuration-invariant hardward constraints. Any further
 87	 * limits which depend upon the configuration can only be checked in
 88	 * @mode_fixup.
 89	 *
 90	 * RETURNS:
 91	 *
 92	 * drm_mode_status Enum
 93	 */
 94	enum drm_mode_status (*mode_valid)(struct drm_bridge *bridge,
 
 95					   const struct drm_display_mode *mode);
 96
 97	/**
 98	 * @mode_fixup:
 99	 *
100	 * This callback is used to validate and adjust a mode. The parameter
101	 * mode is the display mode that should be fed to the next element in
102	 * the display chain, either the final &drm_connector or the next
103	 * &drm_bridge. The parameter adjusted_mode is the input mode the bridge
104	 * requires. It can be modified by this callback and does not need to
105	 * match mode. See also &drm_crtc_state.adjusted_mode for more details.
106	 *
107	 * This is the only hook that allows a bridge to reject a modeset. If
108	 * this function passes all other callbacks must succeed for this
109	 * configuration.
110	 *
111	 * The mode_fixup callback is optional.
 
 
112	 *
113	 * NOTE:
114	 *
115	 * This function is called in the check phase of atomic modesets, which
116	 * can be aborted for any reason (including on userspace's request to
117	 * just check whether a configuration would be possible). Drivers MUST
118	 * NOT touch any persistent state (hardware or software) or data
119	 * structures except the passed in @state parameter.
120	 *
121	 * Also beware that userspace can request its own custom modes, neither
122	 * core nor helpers filter modes to the list of probe modes reported by
123	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
124	 * that modes are filtered consistently put any bridge constraints and
125	 * limits checks into @mode_valid.
126	 *
127	 * RETURNS:
128	 *
129	 * True if an acceptable configuration is possible, false if the modeset
130	 * operation should be rejected.
131	 */
132	bool (*mode_fixup)(struct drm_bridge *bridge,
133			   const struct drm_display_mode *mode,
134			   struct drm_display_mode *adjusted_mode);
135	/**
136	 * @disable:
137	 *
138	 * This callback should disable the bridge. It is called right before
139	 * the preceding element in the display pipe is disabled. If the
140	 * preceding element is a bridge this means it's called before that
141	 * bridge's @disable vfunc. If the preceding element is a &drm_encoder
142	 * it's called right before the &drm_encoder_helper_funcs.disable,
143	 * &drm_encoder_helper_funcs.prepare or &drm_encoder_helper_funcs.dpms
144	 * hook.
145	 *
146	 * The bridge can assume that the display pipe (i.e. clocks and timing
147	 * signals) feeding it is still running when this callback is called.
148	 *
149	 * The disable callback is optional.
 
 
 
 
 
150	 */
151	void (*disable)(struct drm_bridge *bridge);
152
153	/**
154	 * @post_disable:
155	 *
156	 * This callback should disable the bridge. It is called right after the
157	 * preceding element in the display pipe is disabled. If the preceding
158	 * element is a bridge this means it's called after that bridge's
159	 * @post_disable function. If the preceding element is a &drm_encoder
160	 * it's called right after the encoder's
161	 * &drm_encoder_helper_funcs.disable, &drm_encoder_helper_funcs.prepare
162	 * or &drm_encoder_helper_funcs.dpms hook.
163	 *
164	 * The bridge must assume that the display pipe (i.e. clocks and timing
165	 * singals) feeding it is no longer running when this callback is
166	 * called.
167	 *
168	 * The post_disable callback is optional.
 
 
 
 
 
169	 */
170	void (*post_disable)(struct drm_bridge *bridge);
171
172	/**
173	 * @mode_set:
174	 *
175	 * This callback should set the given mode on the bridge. It is called
176	 * after the @mode_set callback for the preceding element in the display
177	 * pipeline has been called already. If the bridge is the first element
178	 * then this would be &drm_encoder_helper_funcs.mode_set. The display
179	 * pipe (i.e.  clocks and timing signals) is off when this function is
180	 * called.
181	 *
182	 * The adjusted_mode parameter is the mode output by the CRTC for the
183	 * first bridge in the chain. It can be different from the mode
184	 * parameter that contains the desired mode for the connector at the end
185	 * of the bridges chain, for instance when the first bridge in the chain
186	 * performs scaling. The adjusted mode is mostly useful for the first
187	 * bridge in the chain and is likely irrelevant for the other bridges.
188	 *
189	 * For atomic drivers the adjusted_mode is the mode stored in
190	 * &drm_crtc_state.adjusted_mode.
191	 *
192	 * NOTE:
193	 *
194	 * If a need arises to store and access modes adjusted for other
195	 * locations than the connection between the CRTC and the first bridge,
196	 * the DRM framework will have to be extended with DRM bridge states.
197	 */
198	void (*mode_set)(struct drm_bridge *bridge,
199			 const struct drm_display_mode *mode,
200			 const struct drm_display_mode *adjusted_mode);
201	/**
202	 * @pre_enable:
203	 *
204	 * This callback should enable the bridge. It is called right before
205	 * the preceding element in the display pipe is enabled. If the
206	 * preceding element is a bridge this means it's called before that
207	 * bridge's @pre_enable function. If the preceding element is a
208	 * &drm_encoder it's called right before the encoder's
209	 * &drm_encoder_helper_funcs.enable, &drm_encoder_helper_funcs.commit or
210	 * &drm_encoder_helper_funcs.dpms hook.
211	 *
212	 * The display pipe (i.e. clocks and timing signals) feeding this bridge
213	 * will not yet be running when this callback is called. The bridge must
214	 * not enable the display link feeding the next bridge in the chain (if
215	 * there is one) when this callback is called.
216	 *
217	 * The pre_enable callback is optional.
 
 
 
 
 
218	 */
219	void (*pre_enable)(struct drm_bridge *bridge);
220
221	/**
222	 * @enable:
223	 *
224	 * This callback should enable the bridge. It is called right after
225	 * the preceding element in the display pipe is enabled. If the
226	 * preceding element is a bridge this means it's called after that
227	 * bridge's @enable function. If the preceding element is a
228	 * &drm_encoder it's called right after the encoder's
229	 * &drm_encoder_helper_funcs.enable, &drm_encoder_helper_funcs.commit or
230	 * &drm_encoder_helper_funcs.dpms hook.
231	 *
232	 * The bridge can assume that the display pipe (i.e. clocks and timing
233	 * signals) feeding it is running when this callback is called. This
234	 * callback must enable the display link feeding the next bridge in the
235	 * chain if there is one.
236	 *
237	 * The enable callback is optional.
 
 
 
 
 
238	 */
239	void (*enable)(struct drm_bridge *bridge);
240
241	/**
242	 * @atomic_pre_enable:
243	 *
244	 * This callback should enable the bridge. It is called right before
245	 * the preceding element in the display pipe is enabled. If the
246	 * preceding element is a bridge this means it's called before that
247	 * bridge's @atomic_pre_enable or @pre_enable function. If the preceding
248	 * element is a &drm_encoder it's called right before the encoder's
249	 * &drm_encoder_helper_funcs.atomic_enable hook.
250	 *
251	 * The display pipe (i.e. clocks and timing signals) feeding this bridge
252	 * will not yet be running when this callback is called. The bridge must
253	 * not enable the display link feeding the next bridge in the chain (if
254	 * there is one) when this callback is called.
255	 *
256	 * Note that this function will only be invoked in the context of an
257	 * atomic commit. It will not be invoked from &drm_bridge_pre_enable. It
258	 * would be prudent to also provide an implementation of @pre_enable if
259	 * you are expecting driver calls into &drm_bridge_pre_enable.
260	 *
261	 * The @atomic_pre_enable callback is optional.
262	 */
263	void (*atomic_pre_enable)(struct drm_bridge *bridge,
264				  struct drm_atomic_state *state);
265
266	/**
267	 * @atomic_enable:
268	 *
269	 * This callback should enable the bridge. It is called right after
270	 * the preceding element in the display pipe is enabled. If the
271	 * preceding element is a bridge this means it's called after that
272	 * bridge's @atomic_enable or @enable function. If the preceding element
273	 * is a &drm_encoder it's called right after the encoder's
274	 * &drm_encoder_helper_funcs.atomic_enable hook.
275	 *
276	 * The bridge can assume that the display pipe (i.e. clocks and timing
277	 * signals) feeding it is running when this callback is called. This
278	 * callback must enable the display link feeding the next bridge in the
279	 * chain if there is one.
280	 *
281	 * Note that this function will only be invoked in the context of an
282	 * atomic commit. It will not be invoked from &drm_bridge_enable. It
283	 * would be prudent to also provide an implementation of @enable if
284	 * you are expecting driver calls into &drm_bridge_enable.
285	 *
286	 * The enable callback is optional.
287	 */
288	void (*atomic_enable)(struct drm_bridge *bridge,
289			      struct drm_atomic_state *state);
290	/**
291	 * @atomic_disable:
292	 *
293	 * This callback should disable the bridge. It is called right before
294	 * the preceding element in the display pipe is disabled. If the
295	 * preceding element is a bridge this means it's called before that
296	 * bridge's @atomic_disable or @disable vfunc. If the preceding element
297	 * is a &drm_encoder it's called right before the
298	 * &drm_encoder_helper_funcs.atomic_disable hook.
299	 *
300	 * The bridge can assume that the display pipe (i.e. clocks and timing
301	 * signals) feeding it is still running when this callback is called.
302	 *
303	 * Note that this function will only be invoked in the context of an
304	 * atomic commit. It will not be invoked from &drm_bridge_disable. It
305	 * would be prudent to also provide an implementation of @disable if
306	 * you are expecting driver calls into &drm_bridge_disable.
307	 *
308	 * The disable callback is optional.
309	 */
310	void (*atomic_disable)(struct drm_bridge *bridge,
311			       struct drm_atomic_state *state);
312
313	/**
314	 * @atomic_post_disable:
315	 *
316	 * This callback should disable the bridge. It is called right after the
317	 * preceding element in the display pipe is disabled. If the preceding
318	 * element is a bridge this means it's called after that bridge's
319	 * @atomic_post_disable or @post_disable function. If the preceding
320	 * element is a &drm_encoder it's called right after the encoder's
321	 * &drm_encoder_helper_funcs.atomic_disable hook.
322	 *
323	 * The bridge must assume that the display pipe (i.e. clocks and timing
324	 * signals) feeding it is no longer running when this callback is
325	 * called.
326	 *
327	 * Note that this function will only be invoked in the context of an
328	 * atomic commit. It will not be invoked from &drm_bridge_post_disable.
329	 * It would be prudent to also provide an implementation of
330	 * @post_disable if you are expecting driver calls into
331	 * &drm_bridge_post_disable.
332	 *
333	 * The post_disable callback is optional.
334	 */
335	void (*atomic_post_disable)(struct drm_bridge *bridge,
336				    struct drm_atomic_state *state);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
337};
338
339/**
340 * struct drm_bridge_timings - timing information for the bridge
341 */
342struct drm_bridge_timings {
343	/**
344	 * @input_bus_flags:
345	 *
346	 * Tells what additional settings for the pixel data on the bus
347	 * this bridge requires (like pixel signal polarity). See also
348	 * &drm_display_info->bus_flags.
349	 */
350	u32 input_bus_flags;
351	/**
352	 * @setup_time_ps:
353	 *
354	 * Defines the time in picoseconds the input data lines must be
355	 * stable before the clock edge.
356	 */
357	u32 setup_time_ps;
358	/**
359	 * @hold_time_ps:
360	 *
361	 * Defines the time in picoseconds taken for the bridge to sample the
362	 * input signal after the clock edge.
363	 */
364	u32 hold_time_ps;
365	/**
366	 * @dual_link:
367	 *
368	 * True if the bus operates in dual-link mode. The exact meaning is
369	 * dependent on the bus type. For LVDS buses, this indicates that even-
370	 * and odd-numbered pixels are received on separate links.
371	 */
372	bool dual_link;
373};
374
375/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
376 * struct drm_bridge - central DRM bridge control structure
377 */
378struct drm_bridge {
 
 
379	/** @dev: DRM device this bridge belongs to */
380	struct drm_device *dev;
381	/** @encoder: encoder to which this bridge is connected */
382	struct drm_encoder *encoder;
383	/** @next: the next bridge in the encoder chain */
384	struct drm_bridge *next;
385#ifdef CONFIG_OF
386	/** @of_node: device node pointer to the bridge */
387	struct device_node *of_node;
388#endif
389	/** @list: to keep track of all added bridges */
390	struct list_head list;
391	/**
392	 * @timings:
393	 *
394	 * the timing specification for the bridge, if any (may be NULL)
395	 */
396	const struct drm_bridge_timings *timings;
397	/** @funcs: control functions */
398	const struct drm_bridge_funcs *funcs;
399	/** @driver_private: pointer to the bridge driver's internal context */
400	void *driver_private;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
401};
402
 
 
 
 
 
 
403void drm_bridge_add(struct drm_bridge *bridge);
 
404void drm_bridge_remove(struct drm_bridge *bridge);
405struct drm_bridge *of_drm_find_bridge(struct device_node *np);
406int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
407		      struct drm_bridge *previous);
 
408
409bool drm_bridge_mode_fixup(struct drm_bridge *bridge,
410			   const struct drm_display_mode *mode,
411			   struct drm_display_mode *adjusted_mode);
412enum drm_mode_status drm_bridge_mode_valid(struct drm_bridge *bridge,
413					   const struct drm_display_mode *mode);
414void drm_bridge_disable(struct drm_bridge *bridge);
415void drm_bridge_post_disable(struct drm_bridge *bridge);
416void drm_bridge_mode_set(struct drm_bridge *bridge,
417			 const struct drm_display_mode *mode,
418			 const struct drm_display_mode *adjusted_mode);
419void drm_bridge_pre_enable(struct drm_bridge *bridge);
420void drm_bridge_enable(struct drm_bridge *bridge);
421
422void drm_atomic_bridge_disable(struct drm_bridge *bridge,
423			       struct drm_atomic_state *state);
424void drm_atomic_bridge_post_disable(struct drm_bridge *bridge,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
425				    struct drm_atomic_state *state);
426void drm_atomic_bridge_pre_enable(struct drm_bridge *bridge,
427				  struct drm_atomic_state *state);
428void drm_atomic_bridge_enable(struct drm_bridge *bridge,
429			      struct drm_atomic_state *state);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
430
431#ifdef CONFIG_DRM_PANEL_BRIDGE
432struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel,
433					u32 connector_type);
 
 
434void drm_panel_bridge_remove(struct drm_bridge *bridge);
 
 
435struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev,
436					     struct drm_panel *panel,
437					     u32 connector_type);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
438#endif
439
440#endif
v6.13.7
   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_BRIDGE_H__
  24#define __DRM_BRIDGE_H__
  25
 
  26#include <linux/ctype.h>
  27#include <linux/list.h>
  28#include <linux/mutex.h>
  29
  30#include <drm/drm_atomic.h>
  31#include <drm/drm_encoder.h>
  32#include <drm/drm_mode_object.h>
  33#include <drm/drm_modes.h>
  34
  35struct device_node;
  36
  37struct drm_bridge;
  38struct drm_bridge_timings;
  39struct drm_connector;
  40struct drm_display_info;
  41struct drm_minor;
  42struct drm_panel;
  43struct edid;
  44struct i2c_adapter;
  45
  46/**
  47 * enum drm_bridge_attach_flags - Flags for &drm_bridge_funcs.attach
  48 */
  49enum drm_bridge_attach_flags {
  50	/**
  51	 * @DRM_BRIDGE_ATTACH_NO_CONNECTOR: When this flag is set the bridge
  52	 * shall not create a drm_connector.
  53	 */
  54	DRM_BRIDGE_ATTACH_NO_CONNECTOR = BIT(0),
  55};
  56
  57/**
  58 * struct drm_bridge_funcs - drm_bridge control functions
  59 */
  60struct drm_bridge_funcs {
  61	/**
  62	 * @attach:
  63	 *
  64	 * This callback is invoked whenever our bridge is being attached to a
  65	 * &drm_encoder. The flags argument tunes the behaviour of the attach
  66	 * operation (see DRM_BRIDGE_ATTACH_*).
  67	 *
  68	 * The @attach callback is optional.
  69	 *
  70	 * RETURNS:
  71	 *
  72	 * Zero on success, error code on failure.
  73	 */
  74	int (*attach)(struct drm_bridge *bridge,
  75		      enum drm_bridge_attach_flags flags);
  76
  77	/**
  78	 * @detach:
  79	 *
  80	 * This callback is invoked whenever our bridge is being detached from a
  81	 * &drm_encoder.
  82	 *
  83	 * The @detach callback is optional.
  84	 */
  85	void (*detach)(struct drm_bridge *bridge);
  86
  87	/**
  88	 * @mode_valid:
  89	 *
  90	 * This callback is used to check if a specific mode is valid in this
  91	 * bridge. This should be implemented if the bridge has some sort of
  92	 * restriction in the modes it can display. For example, a given bridge
  93	 * may be responsible to set a clock value. If the clock can not
  94	 * produce all the values for the available modes then this callback
  95	 * can be used to restrict the number of modes to only the ones that
  96	 * can be displayed.
  97	 *
  98	 * This hook is used by the probe helpers to filter the mode list in
  99	 * drm_helper_probe_single_connector_modes(), and it is used by the
 100	 * atomic helpers to validate modes supplied by userspace in
 101	 * drm_atomic_helper_check_modeset().
 102	 *
 103	 * The @mode_valid callback is optional.
 104	 *
 105	 * NOTE:
 106	 *
 107	 * Since this function is both called from the check phase of an atomic
 108	 * commit, and the mode validation in the probe paths it is not allowed
 109	 * to look at anything else but the passed-in mode, and validate it
 110	 * against configuration-invariant hardware constraints. Any further
 111	 * limits which depend upon the configuration can only be checked in
 112	 * @mode_fixup.
 113	 *
 114	 * RETURNS:
 115	 *
 116	 * drm_mode_status Enum
 117	 */
 118	enum drm_mode_status (*mode_valid)(struct drm_bridge *bridge,
 119					   const struct drm_display_info *info,
 120					   const struct drm_display_mode *mode);
 121
 122	/**
 123	 * @mode_fixup:
 124	 *
 125	 * This callback is used to validate and adjust a mode. The parameter
 126	 * mode is the display mode that should be fed to the next element in
 127	 * the display chain, either the final &drm_connector or the next
 128	 * &drm_bridge. The parameter adjusted_mode is the input mode the bridge
 129	 * requires. It can be modified by this callback and does not need to
 130	 * match mode. See also &drm_crtc_state.adjusted_mode for more details.
 131	 *
 132	 * This is the only hook that allows a bridge to reject a modeset. If
 133	 * this function passes all other callbacks must succeed for this
 134	 * configuration.
 135	 *
 136	 * The mode_fixup callback is optional. &drm_bridge_funcs.mode_fixup()
 137	 * is not called when &drm_bridge_funcs.atomic_check() is implemented,
 138	 * so only one of them should be provided.
 139	 *
 140	 * NOTE:
 141	 *
 142	 * This function is called in the check phase of atomic modesets, which
 143	 * can be aborted for any reason (including on userspace's request to
 144	 * just check whether a configuration would be possible). Drivers MUST
 145	 * NOT touch any persistent state (hardware or software) or data
 146	 * structures except the passed in @state parameter.
 147	 *
 148	 * Also beware that userspace can request its own custom modes, neither
 149	 * core nor helpers filter modes to the list of probe modes reported by
 150	 * the GETCONNECTOR IOCTL and stored in &drm_connector.modes. To ensure
 151	 * that modes are filtered consistently put any bridge constraints and
 152	 * limits checks into @mode_valid.
 153	 *
 154	 * RETURNS:
 155	 *
 156	 * True if an acceptable configuration is possible, false if the modeset
 157	 * operation should be rejected.
 158	 */
 159	bool (*mode_fixup)(struct drm_bridge *bridge,
 160			   const struct drm_display_mode *mode,
 161			   struct drm_display_mode *adjusted_mode);
 162	/**
 163	 * @disable:
 164	 *
 165	 * This callback should disable the bridge. It is called right before
 166	 * the preceding element in the display pipe is disabled. If the
 167	 * preceding element is a bridge this means it's called before that
 168	 * bridge's @disable vfunc. If the preceding element is a &drm_encoder
 169	 * it's called right before the &drm_encoder_helper_funcs.disable,
 170	 * &drm_encoder_helper_funcs.prepare or &drm_encoder_helper_funcs.dpms
 171	 * hook.
 172	 *
 173	 * The bridge can assume that the display pipe (i.e. clocks and timing
 174	 * signals) feeding it is still running when this callback is called.
 175	 *
 176	 * The @disable callback is optional.
 177	 *
 178	 * NOTE:
 179	 *
 180	 * This is deprecated, do not use!
 181	 * New drivers shall use &drm_bridge_funcs.atomic_disable.
 182	 */
 183	void (*disable)(struct drm_bridge *bridge);
 184
 185	/**
 186	 * @post_disable:
 187	 *
 188	 * This callback should disable the bridge. It is called right after the
 189	 * preceding element in the display pipe is disabled. If the preceding
 190	 * element is a bridge this means it's called after that bridge's
 191	 * @post_disable function. If the preceding element is a &drm_encoder
 192	 * it's called right after the encoder's
 193	 * &drm_encoder_helper_funcs.disable, &drm_encoder_helper_funcs.prepare
 194	 * or &drm_encoder_helper_funcs.dpms hook.
 195	 *
 196	 * The bridge must assume that the display pipe (i.e. clocks and timing
 197	 * signals) feeding it is no longer running when this callback is
 198	 * called.
 199	 *
 200	 * The @post_disable callback is optional.
 201	 *
 202	 * NOTE:
 203	 *
 204	 * This is deprecated, do not use!
 205	 * New drivers shall use &drm_bridge_funcs.atomic_post_disable.
 206	 */
 207	void (*post_disable)(struct drm_bridge *bridge);
 208
 209	/**
 210	 * @mode_set:
 211	 *
 212	 * This callback should set the given mode on the bridge. It is called
 213	 * after the @mode_set callback for the preceding element in the display
 214	 * pipeline has been called already. If the bridge is the first element
 215	 * then this would be &drm_encoder_helper_funcs.mode_set. The display
 216	 * pipe (i.e.  clocks and timing signals) is off when this function is
 217	 * called.
 218	 *
 219	 * The adjusted_mode parameter is the mode output by the CRTC for the
 220	 * first bridge in the chain. It can be different from the mode
 221	 * parameter that contains the desired mode for the connector at the end
 222	 * of the bridges chain, for instance when the first bridge in the chain
 223	 * performs scaling. The adjusted mode is mostly useful for the first
 224	 * bridge in the chain and is likely irrelevant for the other bridges.
 225	 *
 226	 * For atomic drivers the adjusted_mode is the mode stored in
 227	 * &drm_crtc_state.adjusted_mode.
 228	 *
 229	 * NOTE:
 230	 *
 231	 * This is deprecated, do not use!
 232	 * New drivers shall set their mode in the
 233	 * &drm_bridge_funcs.atomic_enable operation.
 234	 */
 235	void (*mode_set)(struct drm_bridge *bridge,
 236			 const struct drm_display_mode *mode,
 237			 const struct drm_display_mode *adjusted_mode);
 238	/**
 239	 * @pre_enable:
 240	 *
 241	 * This callback should enable the bridge. It is called right before
 242	 * the preceding element in the display pipe is enabled. If the
 243	 * preceding element is a bridge this means it's called before that
 244	 * bridge's @pre_enable function. If the preceding element is a
 245	 * &drm_encoder it's called right before the encoder's
 246	 * &drm_encoder_helper_funcs.enable, &drm_encoder_helper_funcs.commit or
 247	 * &drm_encoder_helper_funcs.dpms hook.
 248	 *
 249	 * The display pipe (i.e. clocks and timing signals) feeding this bridge
 250	 * will not yet be running when this callback is called. The bridge must
 251	 * not enable the display link feeding the next bridge in the chain (if
 252	 * there is one) when this callback is called.
 253	 *
 254	 * The @pre_enable callback is optional.
 255	 *
 256	 * NOTE:
 257	 *
 258	 * This is deprecated, do not use!
 259	 * New drivers shall use &drm_bridge_funcs.atomic_pre_enable.
 260	 */
 261	void (*pre_enable)(struct drm_bridge *bridge);
 262
 263	/**
 264	 * @enable:
 265	 *
 266	 * This callback should enable the bridge. It is called right after
 267	 * the preceding element in the display pipe is enabled. If the
 268	 * preceding element is a bridge this means it's called after that
 269	 * bridge's @enable function. If the preceding element is a
 270	 * &drm_encoder it's called right after the encoder's
 271	 * &drm_encoder_helper_funcs.enable, &drm_encoder_helper_funcs.commit or
 272	 * &drm_encoder_helper_funcs.dpms hook.
 273	 *
 274	 * The bridge can assume that the display pipe (i.e. clocks and timing
 275	 * signals) feeding it is running when this callback is called. This
 276	 * callback must enable the display link feeding the next bridge in the
 277	 * chain if there is one.
 278	 *
 279	 * The @enable callback is optional.
 280	 *
 281	 * NOTE:
 282	 *
 283	 * This is deprecated, do not use!
 284	 * New drivers shall use &drm_bridge_funcs.atomic_enable.
 285	 */
 286	void (*enable)(struct drm_bridge *bridge);
 287
 288	/**
 289	 * @atomic_pre_enable:
 290	 *
 291	 * This callback should enable the bridge. It is called right before
 292	 * the preceding element in the display pipe is enabled. If the
 293	 * preceding element is a bridge this means it's called before that
 294	 * bridge's @atomic_pre_enable or @pre_enable function. If the preceding
 295	 * element is a &drm_encoder it's called right before the encoder's
 296	 * &drm_encoder_helper_funcs.atomic_enable hook.
 297	 *
 298	 * The display pipe (i.e. clocks and timing signals) feeding this bridge
 299	 * will not yet be running when this callback is called. The bridge must
 300	 * not enable the display link feeding the next bridge in the chain (if
 301	 * there is one) when this callback is called.
 302	 *
 
 
 
 
 
 303	 * The @atomic_pre_enable callback is optional.
 304	 */
 305	void (*atomic_pre_enable)(struct drm_bridge *bridge,
 306				  struct drm_bridge_state *old_bridge_state);
 307
 308	/**
 309	 * @atomic_enable:
 310	 *
 311	 * This callback should enable the bridge. It is called right after
 312	 * the preceding element in the display pipe is enabled. If the
 313	 * preceding element is a bridge this means it's called after that
 314	 * bridge's @atomic_enable or @enable function. If the preceding element
 315	 * is a &drm_encoder it's called right after the encoder's
 316	 * &drm_encoder_helper_funcs.atomic_enable hook.
 317	 *
 318	 * The bridge can assume that the display pipe (i.e. clocks and timing
 319	 * signals) feeding it is running when this callback is called. This
 320	 * callback must enable the display link feeding the next bridge in the
 321	 * chain if there is one.
 322	 *
 323	 * The @atomic_enable callback is optional.
 
 
 
 
 
 324	 */
 325	void (*atomic_enable)(struct drm_bridge *bridge,
 326			      struct drm_bridge_state *old_bridge_state);
 327	/**
 328	 * @atomic_disable:
 329	 *
 330	 * This callback should disable the bridge. It is called right before
 331	 * the preceding element in the display pipe is disabled. If the
 332	 * preceding element is a bridge this means it's called before that
 333	 * bridge's @atomic_disable or @disable vfunc. If the preceding element
 334	 * is a &drm_encoder it's called right before the
 335	 * &drm_encoder_helper_funcs.atomic_disable hook.
 336	 *
 337	 * The bridge can assume that the display pipe (i.e. clocks and timing
 338	 * signals) feeding it is still running when this callback is called.
 339	 *
 340	 * The @atomic_disable callback is optional.
 
 
 
 
 
 341	 */
 342	void (*atomic_disable)(struct drm_bridge *bridge,
 343			       struct drm_bridge_state *old_bridge_state);
 344
 345	/**
 346	 * @atomic_post_disable:
 347	 *
 348	 * This callback should disable the bridge. It is called right after the
 349	 * preceding element in the display pipe is disabled. If the preceding
 350	 * element is a bridge this means it's called after that bridge's
 351	 * @atomic_post_disable or @post_disable function. If the preceding
 352	 * element is a &drm_encoder it's called right after the encoder's
 353	 * &drm_encoder_helper_funcs.atomic_disable hook.
 354	 *
 355	 * The bridge must assume that the display pipe (i.e. clocks and timing
 356	 * signals) feeding it is no longer running when this callback is
 357	 * called.
 358	 *
 359	 * The @atomic_post_disable callback is optional.
 
 
 
 
 
 
 360	 */
 361	void (*atomic_post_disable)(struct drm_bridge *bridge,
 362				    struct drm_bridge_state *old_bridge_state);
 363
 364	/**
 365	 * @atomic_duplicate_state:
 366	 *
 367	 * Duplicate the current bridge state object (which is guaranteed to be
 368	 * non-NULL).
 369	 *
 370	 * The atomic_duplicate_state hook is mandatory if the bridge
 371	 * implements any of the atomic hooks, and should be left unassigned
 372	 * otherwise. For bridges that don't subclass &drm_bridge_state, the
 373	 * drm_atomic_helper_bridge_duplicate_state() helper function shall be
 374	 * used to implement this hook.
 375	 *
 376	 * RETURNS:
 377	 * A valid drm_bridge_state object or NULL if the allocation fails.
 378	 */
 379	struct drm_bridge_state *(*atomic_duplicate_state)(struct drm_bridge *bridge);
 380
 381	/**
 382	 * @atomic_destroy_state:
 383	 *
 384	 * Destroy a bridge state object previously allocated by
 385	 * &drm_bridge_funcs.atomic_duplicate_state().
 386	 *
 387	 * The atomic_destroy_state hook is mandatory if the bridge implements
 388	 * any of the atomic hooks, and should be left unassigned otherwise.
 389	 * For bridges that don't subclass &drm_bridge_state, the
 390	 * drm_atomic_helper_bridge_destroy_state() helper function shall be
 391	 * used to implement this hook.
 392	 */
 393	void (*atomic_destroy_state)(struct drm_bridge *bridge,
 394				     struct drm_bridge_state *state);
 395
 396	/**
 397	 * @atomic_get_output_bus_fmts:
 398	 *
 399	 * Return the supported bus formats on the output end of a bridge.
 400	 * The returned array must be allocated with kmalloc() and will be
 401	 * freed by the caller. If the allocation fails, NULL should be
 402	 * returned. num_output_fmts must be set to the returned array size.
 403	 * Formats listed in the returned array should be listed in decreasing
 404	 * preference order (the core will try all formats until it finds one
 405	 * that works).
 406	 *
 407	 * This method is only called on the last element of the bridge chain
 408	 * as part of the bus format negotiation process that happens in
 409	 * &drm_atomic_bridge_chain_select_bus_fmts().
 410	 * This method is optional. When not implemented, the core will
 411	 * fall back to &drm_connector.display_info.bus_formats[0] if
 412	 * &drm_connector.display_info.num_bus_formats > 0,
 413	 * or to MEDIA_BUS_FMT_FIXED otherwise.
 414	 */
 415	u32 *(*atomic_get_output_bus_fmts)(struct drm_bridge *bridge,
 416					   struct drm_bridge_state *bridge_state,
 417					   struct drm_crtc_state *crtc_state,
 418					   struct drm_connector_state *conn_state,
 419					   unsigned int *num_output_fmts);
 420
 421	/**
 422	 * @atomic_get_input_bus_fmts:
 423	 *
 424	 * Return the supported bus formats on the input end of a bridge for
 425	 * a specific output bus format.
 426	 *
 427	 * The returned array must be allocated with kmalloc() and will be
 428	 * freed by the caller. If the allocation fails, NULL should be
 429	 * returned. num_input_fmts must be set to the returned array size.
 430	 * Formats listed in the returned array should be listed in decreasing
 431	 * preference order (the core will try all formats until it finds one
 432	 * that works). When the format is not supported NULL should be
 433	 * returned and num_input_fmts should be set to 0.
 434	 *
 435	 * This method is called on all elements of the bridge chain as part of
 436	 * the bus format negotiation process that happens in
 437	 * drm_atomic_bridge_chain_select_bus_fmts().
 438	 * This method is optional. When not implemented, the core will bypass
 439	 * bus format negotiation on this element of the bridge without
 440	 * failing, and the previous element in the chain will be passed
 441	 * MEDIA_BUS_FMT_FIXED as its output bus format.
 442	 *
 443	 * Bridge drivers that need to support being linked to bridges that are
 444	 * not supporting bus format negotiation should handle the
 445	 * output_fmt == MEDIA_BUS_FMT_FIXED case appropriately, by selecting a
 446	 * sensible default value or extracting this information from somewhere
 447	 * else (FW property, &drm_display_mode, &drm_display_info, ...)
 448	 *
 449	 * Note: Even if input format selection on the first bridge has no
 450	 * impact on the negotiation process (bus format negotiation stops once
 451	 * we reach the first element of the chain), drivers are expected to
 452	 * return accurate input formats as the input format may be used to
 453	 * configure the CRTC output appropriately.
 454	 */
 455	u32 *(*atomic_get_input_bus_fmts)(struct drm_bridge *bridge,
 456					  struct drm_bridge_state *bridge_state,
 457					  struct drm_crtc_state *crtc_state,
 458					  struct drm_connector_state *conn_state,
 459					  u32 output_fmt,
 460					  unsigned int *num_input_fmts);
 461
 462	/**
 463	 * @atomic_check:
 464	 *
 465	 * This method is responsible for checking bridge state correctness.
 466	 * It can also check the state of the surrounding components in chain
 467	 * to make sure the whole pipeline can work properly.
 468	 *
 469	 * &drm_bridge_funcs.atomic_check() hooks are called in reverse
 470	 * order (from the last to the first bridge).
 471	 *
 472	 * This method is optional. &drm_bridge_funcs.mode_fixup() is not
 473	 * called when &drm_bridge_funcs.atomic_check() is implemented, so only
 474	 * one of them should be provided.
 475	 *
 476	 * If drivers need to tweak &drm_bridge_state.input_bus_cfg.flags or
 477	 * &drm_bridge_state.output_bus_cfg.flags it should happen in
 478	 * this function. By default the &drm_bridge_state.output_bus_cfg.flags
 479	 * field is set to the next bridge
 480	 * &drm_bridge_state.input_bus_cfg.flags value or
 481	 * &drm_connector.display_info.bus_flags if the bridge is the last
 482	 * element in the chain.
 483	 *
 484	 * RETURNS:
 485	 * zero if the check passed, a negative error code otherwise.
 486	 */
 487	int (*atomic_check)(struct drm_bridge *bridge,
 488			    struct drm_bridge_state *bridge_state,
 489			    struct drm_crtc_state *crtc_state,
 490			    struct drm_connector_state *conn_state);
 491
 492	/**
 493	 * @atomic_reset:
 494	 *
 495	 * Reset the bridge to a predefined state (or retrieve its current
 496	 * state) and return a &drm_bridge_state object matching this state.
 497	 * This function is called at attach time.
 498	 *
 499	 * The atomic_reset hook is mandatory if the bridge implements any of
 500	 * the atomic hooks, and should be left unassigned otherwise. For
 501	 * bridges that don't subclass &drm_bridge_state, the
 502	 * drm_atomic_helper_bridge_reset() helper function shall be used to
 503	 * implement this hook.
 504	 *
 505	 * Note that the atomic_reset() semantics is not exactly matching the
 506	 * reset() semantics found on other components (connector, plane, ...).
 507	 *
 508	 * 1. The reset operation happens when the bridge is attached, not when
 509	 *    drm_mode_config_reset() is called
 510	 * 2. It's meant to be used exclusively on bridges that have been
 511	 *    converted to the ATOMIC API
 512	 *
 513	 * RETURNS:
 514	 * A valid drm_bridge_state object in case of success, an ERR_PTR()
 515	 * giving the reason of the failure otherwise.
 516	 */
 517	struct drm_bridge_state *(*atomic_reset)(struct drm_bridge *bridge);
 518
 519	/**
 520	 * @detect:
 521	 *
 522	 * Check if anything is attached to the bridge output.
 523	 *
 524	 * This callback is optional, if not implemented the bridge will be
 525	 * considered as always having a component attached to its output.
 526	 * Bridges that implement this callback shall set the
 527	 * DRM_BRIDGE_OP_DETECT flag in their &drm_bridge->ops.
 528	 *
 529	 * RETURNS:
 530	 *
 531	 * drm_connector_status indicating the bridge output status.
 532	 */
 533	enum drm_connector_status (*detect)(struct drm_bridge *bridge);
 534
 535	/**
 536	 * @get_modes:
 537	 *
 538	 * Fill all modes currently valid for the sink into the &drm_connector
 539	 * with drm_mode_probed_add().
 540	 *
 541	 * The @get_modes callback is mostly intended to support non-probeable
 542	 * displays such as many fixed panels. Bridges that support reading
 543	 * EDID shall leave @get_modes unimplemented and implement the
 544	 * &drm_bridge_funcs->edid_read callback instead.
 545	 *
 546	 * This callback is optional. Bridges that implement it shall set the
 547	 * DRM_BRIDGE_OP_MODES flag in their &drm_bridge->ops.
 548	 *
 549	 * The connector parameter shall be used for the sole purpose of
 550	 * filling modes, and shall not be stored internally by bridge drivers
 551	 * for future usage.
 552	 *
 553	 * RETURNS:
 554	 *
 555	 * The number of modes added by calling drm_mode_probed_add().
 556	 */
 557	int (*get_modes)(struct drm_bridge *bridge,
 558			 struct drm_connector *connector);
 559
 560	/**
 561	 * @edid_read:
 562	 *
 563	 * Read the EDID data of the connected display.
 564	 *
 565	 * The @edid_read callback is the preferred way of reporting mode
 566	 * information for a display connected to the bridge output. Bridges
 567	 * that support reading EDID shall implement this callback and leave
 568	 * the @get_modes callback unimplemented.
 569	 *
 570	 * The caller of this operation shall first verify the output
 571	 * connection status and refrain from reading EDID from a disconnected
 572	 * output.
 573	 *
 574	 * This callback is optional. Bridges that implement it shall set the
 575	 * DRM_BRIDGE_OP_EDID flag in their &drm_bridge->ops.
 576	 *
 577	 * The connector parameter shall be used for the sole purpose of EDID
 578	 * retrieval, and shall not be stored internally by bridge drivers for
 579	 * future usage.
 580	 *
 581	 * RETURNS:
 582	 *
 583	 * An edid structure newly allocated with drm_edid_alloc() or returned
 584	 * from drm_edid_read() family of functions on success, or NULL
 585	 * otherwise. The caller is responsible for freeing the returned edid
 586	 * structure with drm_edid_free().
 587	 */
 588	const struct drm_edid *(*edid_read)(struct drm_bridge *bridge,
 589					    struct drm_connector *connector);
 590
 591	/**
 592	 * @hpd_notify:
 593	 *
 594	 * Notify the bridge of hot plug detection.
 595	 *
 596	 * This callback is optional, it may be implemented by bridges that
 597	 * need to be notified of display connection or disconnection for
 598	 * internal reasons. One use case is to reset the internal state of CEC
 599	 * controllers for HDMI bridges.
 600	 */
 601	void (*hpd_notify)(struct drm_bridge *bridge,
 602			   enum drm_connector_status status);
 603
 604	/**
 605	 * @hpd_enable:
 606	 *
 607	 * Enable hot plug detection. From now on the bridge shall call
 608	 * drm_bridge_hpd_notify() each time a change is detected in the output
 609	 * connection status, until hot plug detection gets disabled with
 610	 * @hpd_disable.
 611	 *
 612	 * This callback is optional and shall only be implemented by bridges
 613	 * that support hot-plug notification without polling. Bridges that
 614	 * implement it shall also implement the @hpd_disable callback and set
 615	 * the DRM_BRIDGE_OP_HPD flag in their &drm_bridge->ops.
 616	 */
 617	void (*hpd_enable)(struct drm_bridge *bridge);
 618
 619	/**
 620	 * @hpd_disable:
 621	 *
 622	 * Disable hot plug detection. Once this function returns the bridge
 623	 * shall not call drm_bridge_hpd_notify() when a change in the output
 624	 * connection status occurs.
 625	 *
 626	 * This callback is optional and shall only be implemented by bridges
 627	 * that support hot-plug notification without polling. Bridges that
 628	 * implement it shall also implement the @hpd_enable callback and set
 629	 * the DRM_BRIDGE_OP_HPD flag in their &drm_bridge->ops.
 630	 */
 631	void (*hpd_disable)(struct drm_bridge *bridge);
 632
 633	/**
 634	 * @hdmi_tmds_char_rate_valid:
 635	 *
 636	 * Check whether a particular TMDS character rate is supported by the
 637	 * driver.
 638	 *
 639	 * This callback is optional and should only be implemented by the
 640	 * bridges that take part in the HDMI connector implementation. Bridges
 641	 * that implement it shall set the DRM_BRIDGE_OP_HDMI flag in their
 642	 * &drm_bridge->ops.
 643	 *
 644	 * Returns:
 645	 *
 646	 * Either &drm_mode_status.MODE_OK or one of the failure reasons
 647	 * in &enum drm_mode_status.
 648	 */
 649	enum drm_mode_status
 650	(*hdmi_tmds_char_rate_valid)(const struct drm_bridge *bridge,
 651				     const struct drm_display_mode *mode,
 652				     unsigned long long tmds_rate);
 653
 654	/**
 655	 * @hdmi_clear_infoframe:
 656	 *
 657	 * This callback clears the infoframes in the hardware during commit.
 658	 * It will be called multiple times, once for every disabled infoframe
 659	 * type.
 660	 *
 661	 * This callback is optional but it must be implemented by bridges that
 662	 * set the DRM_BRIDGE_OP_HDMI flag in their &drm_bridge->ops.
 663	 */
 664	int (*hdmi_clear_infoframe)(struct drm_bridge *bridge,
 665				    enum hdmi_infoframe_type type);
 666	/**
 667	 * @hdmi_write_infoframe:
 668	 *
 669	 * Program the infoframe into the hardware. It will be called multiple
 670	 * times, once for every updated infoframe type.
 671	 *
 672	 * This callback is optional but it must be implemented by bridges that
 673	 * set the DRM_BRIDGE_OP_HDMI flag in their &drm_bridge->ops.
 674	 */
 675	int (*hdmi_write_infoframe)(struct drm_bridge *bridge,
 676				    enum hdmi_infoframe_type type,
 677				    const u8 *buffer, size_t len);
 678
 679	/**
 680	 * @debugfs_init:
 681	 *
 682	 * Allows bridges to create bridge-specific debugfs files.
 683	 */
 684	void (*debugfs_init)(struct drm_bridge *bridge, struct dentry *root);
 685};
 686
 687/**
 688 * struct drm_bridge_timings - timing information for the bridge
 689 */
 690struct drm_bridge_timings {
 691	/**
 692	 * @input_bus_flags:
 693	 *
 694	 * Tells what additional settings for the pixel data on the bus
 695	 * this bridge requires (like pixel signal polarity). See also
 696	 * &drm_display_info->bus_flags.
 697	 */
 698	u32 input_bus_flags;
 699	/**
 700	 * @setup_time_ps:
 701	 *
 702	 * Defines the time in picoseconds the input data lines must be
 703	 * stable before the clock edge.
 704	 */
 705	u32 setup_time_ps;
 706	/**
 707	 * @hold_time_ps:
 708	 *
 709	 * Defines the time in picoseconds taken for the bridge to sample the
 710	 * input signal after the clock edge.
 711	 */
 712	u32 hold_time_ps;
 713	/**
 714	 * @dual_link:
 715	 *
 716	 * True if the bus operates in dual-link mode. The exact meaning is
 717	 * dependent on the bus type. For LVDS buses, this indicates that even-
 718	 * and odd-numbered pixels are received on separate links.
 719	 */
 720	bool dual_link;
 721};
 722
 723/**
 724 * enum drm_bridge_ops - Bitmask of operations supported by the bridge
 725 */
 726enum drm_bridge_ops {
 727	/**
 728	 * @DRM_BRIDGE_OP_DETECT: The bridge can detect displays connected to
 729	 * its output. Bridges that set this flag shall implement the
 730	 * &drm_bridge_funcs->detect callback.
 731	 */
 732	DRM_BRIDGE_OP_DETECT = BIT(0),
 733	/**
 734	 * @DRM_BRIDGE_OP_EDID: The bridge can retrieve the EDID of the display
 735	 * connected to its output. Bridges that set this flag shall implement
 736	 * the &drm_bridge_funcs->edid_read callback.
 737	 */
 738	DRM_BRIDGE_OP_EDID = BIT(1),
 739	/**
 740	 * @DRM_BRIDGE_OP_HPD: The bridge can detect hot-plug and hot-unplug
 741	 * without requiring polling. Bridges that set this flag shall
 742	 * implement the &drm_bridge_funcs->hpd_enable and
 743	 * &drm_bridge_funcs->hpd_disable callbacks if they support enabling
 744	 * and disabling hot-plug detection dynamically.
 745	 */
 746	DRM_BRIDGE_OP_HPD = BIT(2),
 747	/**
 748	 * @DRM_BRIDGE_OP_MODES: The bridge can retrieve the modes supported
 749	 * by the display at its output. This does not include reading EDID
 750	 * which is separately covered by @DRM_BRIDGE_OP_EDID. Bridges that set
 751	 * this flag shall implement the &drm_bridge_funcs->get_modes callback.
 752	 */
 753	DRM_BRIDGE_OP_MODES = BIT(3),
 754	/**
 755	 * @DRM_BRIDGE_OP_HDMI: The bridge provides HDMI connector operations,
 756	 * including infoframes support. Bridges that set this flag must
 757	 * implement the &drm_bridge_funcs->write_infoframe callback.
 758	 *
 759	 * Note: currently there can be at most one bridge in a chain that sets
 760	 * this bit. This is to simplify corresponding glue code in connector
 761	 * drivers.
 762	 */
 763	DRM_BRIDGE_OP_HDMI = BIT(4),
 764};
 765
 766/**
 767 * struct drm_bridge - central DRM bridge control structure
 768 */
 769struct drm_bridge {
 770	/** @base: inherit from &drm_private_object */
 771	struct drm_private_obj base;
 772	/** @dev: DRM device this bridge belongs to */
 773	struct drm_device *dev;
 774	/** @encoder: encoder to which this bridge is connected */
 775	struct drm_encoder *encoder;
 776	/** @chain_node: used to form a bridge chain */
 777	struct list_head chain_node;
 
 778	/** @of_node: device node pointer to the bridge */
 779	struct device_node *of_node;
 
 780	/** @list: to keep track of all added bridges */
 781	struct list_head list;
 782	/**
 783	 * @timings:
 784	 *
 785	 * the timing specification for the bridge, if any (may be NULL)
 786	 */
 787	const struct drm_bridge_timings *timings;
 788	/** @funcs: control functions */
 789	const struct drm_bridge_funcs *funcs;
 790	/** @driver_private: pointer to the bridge driver's internal context */
 791	void *driver_private;
 792	/** @ops: bitmask of operations supported by the bridge */
 793	enum drm_bridge_ops ops;
 794	/**
 795	 * @type: Type of the connection at the bridge output
 796	 * (DRM_MODE_CONNECTOR_*). For bridges at the end of this chain this
 797	 * identifies the type of connected display.
 798	 */
 799	int type;
 800	/**
 801	 * @interlace_allowed: Indicate that the bridge can handle interlaced
 802	 * modes.
 803	 */
 804	bool interlace_allowed;
 805	/**
 806	 * @ycbcr_420_allowed: Indicate that the bridge can handle YCbCr 420
 807	 * output.
 808	 */
 809	bool ycbcr_420_allowed;
 810	/**
 811	 * @pre_enable_prev_first: The bridge requires that the prev
 812	 * bridge @pre_enable function is called before its @pre_enable,
 813	 * and conversely for post_disable. This is most frequently a
 814	 * requirement for DSI devices which need the host to be initialised
 815	 * before the peripheral.
 816	 */
 817	bool pre_enable_prev_first;
 818	/**
 819	 * @ddc: Associated I2C adapter for DDC access, if any.
 820	 */
 821	struct i2c_adapter *ddc;
 822	/** private: */
 823	/**
 824	 * @hpd_mutex: Protects the @hpd_cb and @hpd_data fields.
 825	 */
 826	struct mutex hpd_mutex;
 827	/**
 828	 * @hpd_cb: Hot plug detection callback, registered with
 829	 * drm_bridge_hpd_enable().
 830	 */
 831	void (*hpd_cb)(void *data, enum drm_connector_status status);
 832	/**
 833	 * @hpd_data: Private data passed to the Hot plug detection callback
 834	 * @hpd_cb.
 835	 */
 836	void *hpd_data;
 837
 838	/**
 839	 * @vendor: Vendor of the product to be used for the SPD InfoFrame
 840	 * generation. This is required if @DRM_BRIDGE_OP_HDMI is set.
 841	 */
 842	const char *vendor;
 843
 844	/**
 845	 * @product: Name of the product to be used for the SPD InfoFrame
 846	 * generation. This is required if @DRM_BRIDGE_OP_HDMI is set.
 847	 */
 848	const char *product;
 849
 850	/**
 851	 * @supported_formats: Bitmask of @hdmi_colorspace listing supported
 852	 * output formats. This is only relevant if @DRM_BRIDGE_OP_HDMI is set.
 853	 */
 854	unsigned int supported_formats;
 855
 856	/**
 857	 * @max_bpc: Maximum bits per char the HDMI bridge supports. Allowed
 858	 * values are 8, 10 and 12. This is only relevant if
 859	 * @DRM_BRIDGE_OP_HDMI is set.
 860	 */
 861	unsigned int max_bpc;
 862};
 863
 864static inline struct drm_bridge *
 865drm_priv_to_bridge(struct drm_private_obj *priv)
 866{
 867	return container_of(priv, struct drm_bridge, base);
 868}
 869
 870void drm_bridge_add(struct drm_bridge *bridge);
 871int devm_drm_bridge_add(struct device *dev, struct drm_bridge *bridge);
 872void drm_bridge_remove(struct drm_bridge *bridge);
 
 873int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
 874		      struct drm_bridge *previous,
 875		      enum drm_bridge_attach_flags flags);
 876
 877#ifdef CONFIG_OF
 878struct drm_bridge *of_drm_find_bridge(struct device_node *np);
 879#else
 880static inline struct drm_bridge *of_drm_find_bridge(struct device_node *np)
 881{
 882	return NULL;
 883}
 884#endif
 
 
 
 
 885
 886/**
 887 * drm_bridge_get_next_bridge() - Get the next bridge in the chain
 888 * @bridge: bridge object
 889 *
 890 * RETURNS:
 891 * the next bridge in the chain after @bridge, or NULL if @bridge is the last.
 892 */
 893static inline struct drm_bridge *
 894drm_bridge_get_next_bridge(struct drm_bridge *bridge)
 895{
 896	if (list_is_last(&bridge->chain_node, &bridge->encoder->bridge_chain))
 897		return NULL;
 898
 899	return list_next_entry(bridge, chain_node);
 900}
 901
 902/**
 903 * drm_bridge_get_prev_bridge() - Get the previous bridge in the chain
 904 * @bridge: bridge object
 905 *
 906 * RETURNS:
 907 * the previous bridge in the chain, or NULL if @bridge is the first.
 908 */
 909static inline struct drm_bridge *
 910drm_bridge_get_prev_bridge(struct drm_bridge *bridge)
 911{
 912	if (list_is_first(&bridge->chain_node, &bridge->encoder->bridge_chain))
 913		return NULL;
 914
 915	return list_prev_entry(bridge, chain_node);
 916}
 917
 918/**
 919 * drm_bridge_chain_get_first_bridge() - Get the first bridge in the chain
 920 * @encoder: encoder object
 921 *
 922 * RETURNS:
 923 * the first bridge in the chain, or NULL if @encoder has no bridge attached
 924 * to it.
 925 */
 926static inline struct drm_bridge *
 927drm_bridge_chain_get_first_bridge(struct drm_encoder *encoder)
 928{
 929	return list_first_entry_or_null(&encoder->bridge_chain,
 930					struct drm_bridge, chain_node);
 931}
 932
 933/**
 934 * drm_for_each_bridge_in_chain() - Iterate over all bridges present in a chain
 935 * @encoder: the encoder to iterate bridges on
 936 * @bridge: a bridge pointer updated to point to the current bridge at each
 937 *	    iteration
 938 *
 939 * Iterate over all bridges present in the bridge chain attached to @encoder.
 940 */
 941#define drm_for_each_bridge_in_chain(encoder, bridge)			\
 942	list_for_each_entry(bridge, &(encoder)->bridge_chain, chain_node)
 943
 944enum drm_mode_status
 945drm_bridge_chain_mode_valid(struct drm_bridge *bridge,
 946			    const struct drm_display_info *info,
 947			    const struct drm_display_mode *mode);
 948void drm_bridge_chain_mode_set(struct drm_bridge *bridge,
 949			       const struct drm_display_mode *mode,
 950			       const struct drm_display_mode *adjusted_mode);
 951
 952int drm_atomic_bridge_chain_check(struct drm_bridge *bridge,
 953				  struct drm_crtc_state *crtc_state,
 954				  struct drm_connector_state *conn_state);
 955void drm_atomic_bridge_chain_disable(struct drm_bridge *bridge,
 956				     struct drm_atomic_state *state);
 957void drm_atomic_bridge_chain_post_disable(struct drm_bridge *bridge,
 958					  struct drm_atomic_state *state);
 959void drm_atomic_bridge_chain_pre_enable(struct drm_bridge *bridge,
 960					struct drm_atomic_state *state);
 961void drm_atomic_bridge_chain_enable(struct drm_bridge *bridge,
 962				    struct drm_atomic_state *state);
 963
 964u32 *
 965drm_atomic_helper_bridge_propagate_bus_fmt(struct drm_bridge *bridge,
 966					struct drm_bridge_state *bridge_state,
 967					struct drm_crtc_state *crtc_state,
 968					struct drm_connector_state *conn_state,
 969					u32 output_fmt,
 970					unsigned int *num_input_fmts);
 971
 972enum drm_connector_status drm_bridge_detect(struct drm_bridge *bridge);
 973int drm_bridge_get_modes(struct drm_bridge *bridge,
 974			 struct drm_connector *connector);
 975const struct drm_edid *drm_bridge_edid_read(struct drm_bridge *bridge,
 976					    struct drm_connector *connector);
 977void drm_bridge_hpd_enable(struct drm_bridge *bridge,
 978			   void (*cb)(void *data,
 979				      enum drm_connector_status status),
 980			   void *data);
 981void drm_bridge_hpd_disable(struct drm_bridge *bridge);
 982void drm_bridge_hpd_notify(struct drm_bridge *bridge,
 983			   enum drm_connector_status status);
 984
 985#ifdef CONFIG_DRM_PANEL_BRIDGE
 986bool drm_bridge_is_panel(const struct drm_bridge *bridge);
 987struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel);
 988struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel,
 989					      u32 connector_type);
 990void drm_panel_bridge_remove(struct drm_bridge *bridge);
 991int drm_panel_bridge_set_orientation(struct drm_connector *connector,
 992				     struct drm_bridge *bridge);
 993struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev,
 994					     struct drm_panel *panel);
 995struct drm_bridge *devm_drm_panel_bridge_add_typed(struct device *dev,
 996						   struct drm_panel *panel,
 997						   u32 connector_type);
 998struct drm_bridge *drmm_panel_bridge_add(struct drm_device *drm,
 999					     struct drm_panel *panel);
1000struct drm_connector *drm_panel_bridge_connector(struct drm_bridge *bridge);
1001#else
1002static inline bool drm_bridge_is_panel(const struct drm_bridge *bridge)
1003{
1004	return false;
1005}
1006
1007static inline int drm_panel_bridge_set_orientation(struct drm_connector *connector,
1008						   struct drm_bridge *bridge)
1009{
1010	return -EINVAL;
1011}
1012#endif
1013
1014#if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL_BRIDGE)
1015struct drm_bridge *devm_drm_of_get_bridge(struct device *dev, struct device_node *node,
1016					  u32 port, u32 endpoint);
1017struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm, struct device_node *node,
1018					  u32 port, u32 endpoint);
1019#else
1020static inline struct drm_bridge *devm_drm_of_get_bridge(struct device *dev,
1021							struct device_node *node,
1022							u32 port,
1023							u32 endpoint)
1024{
1025	return ERR_PTR(-ENODEV);
1026}
1027
1028static inline struct drm_bridge *drmm_of_get_bridge(struct drm_device *drm,
1029						     struct device_node *node,
1030						     u32 port,
1031						     u32 endpoint)
1032{
1033	return ERR_PTR(-ENODEV);
1034}
1035#endif
1036
1037#endif