xref: /linux/include/drm/drm_fb_helper.h (revision fa84cf094ef9667e2b91c104b0a788fd1896f482)
1 /*
2  * Copyright (c) 2006-2009 Red Hat Inc.
3  * Copyright (c) 2006-2008 Intel Corporation
4  * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
5  *
6  * DRM framebuffer helper functions
7  *
8  * Permission to use, copy, modify, distribute, and sell this software and its
9  * documentation for any purpose is hereby granted without fee, provided that
10  * the above copyright notice appear in all copies and that both that copyright
11  * notice and this permission notice appear in supporting documentation, and
12  * that the name of the copyright holders not be used in advertising or
13  * publicity pertaining to distribution of the software without specific,
14  * written prior permission.  The copyright holders make no representations
15  * about the suitability of this software for any purpose.  It is provided "as
16  * is" without express or implied warranty.
17  *
18  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
19  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
20  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
21  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
22  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
23  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
24  * OF THIS SOFTWARE.
25  *
26  * Authors:
27  *      Dave Airlie <airlied@linux.ie>
28  *      Jesse Barnes <jesse.barnes@intel.com>
29  */
30 #ifndef DRM_FB_HELPER_H
31 #define DRM_FB_HELPER_H
32 
33 struct drm_fb_helper;
34 
35 #include <drm/drm_crtc.h>
36 #include <drm/drm_device.h>
37 #include <linux/kgdb.h>
38 
39 enum mode_set_atomic {
40 	LEAVE_ATOMIC_MODE_SET,
41 	ENTER_ATOMIC_MODE_SET,
42 };
43 
44 struct drm_fb_offset {
45 	int x, y;
46 };
47 
48 struct drm_fb_helper_crtc {
49 	struct drm_mode_set mode_set;
50 	struct drm_display_mode *desired_mode;
51 	int x, y;
52 	int rotation;
53 };
54 
55 /**
56  * struct drm_fb_helper_surface_size - describes fbdev size and scanout surface size
57  * @fb_width: fbdev width
58  * @fb_height: fbdev height
59  * @surface_width: scanout buffer width
60  * @surface_height: scanout buffer height
61  * @surface_bpp: scanout buffer bpp
62  * @surface_depth: scanout buffer depth
63  *
64  * Note that the scanout surface width/height may be larger than the fbdev
65  * width/height.  In case of multiple displays, the scanout surface is sized
66  * according to the largest width/height (so it is large enough for all CRTCs
67  * to scanout).  But the fbdev width/height is sized to the minimum width/
68  * height of all the displays.  This ensures that fbcon fits on the smallest
69  * of the attached displays.
70  *
71  * So what is passed to drm_fb_helper_fill_var() should be fb_width/fb_height,
72  * rather than the surface size.
73  */
74 struct drm_fb_helper_surface_size {
75 	u32 fb_width;
76 	u32 fb_height;
77 	u32 surface_width;
78 	u32 surface_height;
79 	u32 surface_bpp;
80 	u32 surface_depth;
81 };
82 
83 /**
84  * struct drm_fb_helper_funcs - driver callbacks for the fbdev emulation library
85  *
86  * Driver callbacks used by the fbdev emulation helper library.
87  */
88 struct drm_fb_helper_funcs {
89 	/**
90 	 * @fb_probe:
91 	 *
92 	 * Driver callback to allocate and initialize the fbdev info structure.
93 	 * Furthermore it also needs to allocate the DRM framebuffer used to
94 	 * back the fbdev.
95 	 *
96 	 * This callback is mandatory.
97 	 *
98 	 * RETURNS:
99 	 *
100 	 * The driver should return 0 on success and a negative error code on
101 	 * failure.
102 	 */
103 	int (*fb_probe)(struct drm_fb_helper *helper,
104 			struct drm_fb_helper_surface_size *sizes);
105 
106 	/**
107 	 * @initial_config:
108 	 *
109 	 * Driver callback to setup an initial fbdev display configuration.
110 	 * Drivers can use this callback to tell the fbdev emulation what the
111 	 * preferred initial configuration is. This is useful to implement
112 	 * smooth booting where the fbdev (and subsequently all userspace) never
113 	 * changes the mode, but always inherits the existing configuration.
114 	 *
115 	 * This callback is optional.
116 	 *
117 	 * RETURNS:
118 	 *
119 	 * The driver should return true if a suitable initial configuration has
120 	 * been filled out and false when the fbdev helper should fall back to
121 	 * the default probing logic.
122 	 */
123 	bool (*initial_config)(struct drm_fb_helper *fb_helper,
124 			       struct drm_fb_helper_crtc **crtcs,
125 			       struct drm_display_mode **modes,
126 			       struct drm_fb_offset *offsets,
127 			       bool *enabled, int width, int height);
128 };
129 
130 struct drm_fb_helper_connector {
131 	struct drm_connector *connector;
132 };
133 
134 /**
135  * struct drm_fb_helper - main structure to emulate fbdev on top of KMS
136  * @fb: Scanout framebuffer object
137  * @dev: DRM device
138  * @crtc_count: number of possible CRTCs
139  * @crtc_info: per-CRTC helper state (mode, x/y offset, etc)
140  * @connector_count: number of connected connectors
141  * @connector_info_alloc_count: size of connector_info
142  * @funcs: driver callbacks for fb helper
143  * @fbdev: emulated fbdev device info struct
144  * @pseudo_palette: fake palette of 16 colors
145  * @dirty_clip: clip rectangle used with deferred_io to accumulate damage to
146  *              the screen buffer
147  * @dirty_lock: spinlock protecting @dirty_clip
148  * @dirty_work: worker used to flush the framebuffer
149  * @resume_work: worker used during resume if the console lock is already taken
150  *
151  * This is the main structure used by the fbdev helpers. Drivers supporting
152  * fbdev emulation should embedded this into their overall driver structure.
153  * Drivers must also fill out a &struct drm_fb_helper_funcs with a few
154  * operations.
155  */
156 struct drm_fb_helper {
157 	struct drm_framebuffer *fb;
158 	struct drm_device *dev;
159 	int crtc_count;
160 	struct drm_fb_helper_crtc *crtc_info;
161 	int connector_count;
162 	int connector_info_alloc_count;
163 	/**
164 	 * @sw_rotations:
165 	 * Bitmask of all rotations requested for panel-orientation which
166 	 * could not be handled in hardware. If only one bit is set
167 	 * fbdev->fbcon_rotate_hint gets set to the requested rotation.
168 	 */
169 	int sw_rotations;
170 	/**
171 	 * @connector_info:
172 	 *
173 	 * Array of per-connector information. Do not iterate directly, but use
174 	 * drm_fb_helper_for_each_connector.
175 	 */
176 	struct drm_fb_helper_connector **connector_info;
177 	const struct drm_fb_helper_funcs *funcs;
178 	struct fb_info *fbdev;
179 	u32 pseudo_palette[17];
180 	struct drm_clip_rect dirty_clip;
181 	spinlock_t dirty_lock;
182 	struct work_struct dirty_work;
183 	struct work_struct resume_work;
184 
185 	/**
186 	 * @lock:
187 	 *
188 	 * Top-level FBDEV helper lock. This protects all internal data
189 	 * structures and lists, such as @connector_info and @crtc_info.
190 	 *
191 	 * FIXME: fbdev emulation locking is a mess and long term we want to
192 	 * protect all helper internal state with this lock as well as reduce
193 	 * core KMS locking as much as possible.
194 	 */
195 	struct mutex lock;
196 
197 	/**
198 	 * @kernel_fb_list:
199 	 *
200 	 * Entry on the global kernel_fb_helper_list, used for kgdb entry/exit.
201 	 */
202 	struct list_head kernel_fb_list;
203 
204 	/**
205 	 * @delayed_hotplug:
206 	 *
207 	 * A hotplug was received while fbdev wasn't in control of the DRM
208 	 * device, i.e. another KMS master was active. The output configuration
209 	 * needs to be reprobe when fbdev is in control again.
210 	 */
211 	bool delayed_hotplug;
212 
213 	/**
214 	 * @deferred_setup:
215 	 *
216 	 * If no outputs are connected (disconnected or unknown) the FB helper
217 	 * code will defer setup until at least one of the outputs shows up.
218 	 * This field keeps track of the status so that setup can be retried
219 	 * at every hotplug event until it succeeds eventually.
220 	 *
221 	 * Protected by @lock.
222 	 */
223 	bool deferred_setup;
224 
225 	/**
226 	 * @preferred_bpp:
227 	 *
228 	 * Temporary storage for the driver's preferred BPP setting passed to
229 	 * FB helper initialization. This needs to be tracked so that deferred
230 	 * FB helper setup can pass this on.
231 	 *
232 	 * See also: @deferred_setup
233 	 */
234 	int preferred_bpp;
235 };
236 
237 /**
238  * define DRM_FB_HELPER_DEFAULT_OPS - helper define for drm drivers
239  *
240  * Helper define to register default implementations of drm_fb_helper
241  * functions. To be used in struct fb_ops of drm drivers.
242  */
243 #define DRM_FB_HELPER_DEFAULT_OPS \
244 	.fb_check_var	= drm_fb_helper_check_var, \
245 	.fb_set_par	= drm_fb_helper_set_par, \
246 	.fb_setcmap	= drm_fb_helper_setcmap, \
247 	.fb_blank	= drm_fb_helper_blank, \
248 	.fb_pan_display	= drm_fb_helper_pan_display, \
249 	.fb_debug_enter = drm_fb_helper_debug_enter, \
250 	.fb_debug_leave = drm_fb_helper_debug_leave, \
251 	.fb_ioctl	= drm_fb_helper_ioctl
252 
253 #ifdef CONFIG_DRM_FBDEV_EMULATION
254 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
255 			   const struct drm_fb_helper_funcs *funcs);
256 int drm_fb_helper_init(struct drm_device *dev,
257 		       struct drm_fb_helper *helper, int max_conn);
258 void drm_fb_helper_fini(struct drm_fb_helper *helper);
259 int drm_fb_helper_blank(int blank, struct fb_info *info);
260 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
261 			      struct fb_info *info);
262 int drm_fb_helper_set_par(struct fb_info *info);
263 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
264 			    struct fb_info *info);
265 
266 int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper);
267 
268 struct fb_info *drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper);
269 void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper);
270 void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
271 			    uint32_t fb_width, uint32_t fb_height);
272 void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
273 			    uint32_t depth);
274 
275 void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper);
276 
277 void drm_fb_helper_deferred_io(struct fb_info *info,
278 			       struct list_head *pagelist);
279 int drm_fb_helper_defio_init(struct drm_fb_helper *fb_helper);
280 
281 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
282 			       size_t count, loff_t *ppos);
283 ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
284 				size_t count, loff_t *ppos);
285 
286 void drm_fb_helper_sys_fillrect(struct fb_info *info,
287 				const struct fb_fillrect *rect);
288 void drm_fb_helper_sys_copyarea(struct fb_info *info,
289 				const struct fb_copyarea *area);
290 void drm_fb_helper_sys_imageblit(struct fb_info *info,
291 				 const struct fb_image *image);
292 
293 void drm_fb_helper_cfb_fillrect(struct fb_info *info,
294 				const struct fb_fillrect *rect);
295 void drm_fb_helper_cfb_copyarea(struct fb_info *info,
296 				const struct fb_copyarea *area);
297 void drm_fb_helper_cfb_imageblit(struct fb_info *info,
298 				 const struct fb_image *image);
299 
300 void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend);
301 void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
302 					bool suspend);
303 
304 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info);
305 
306 int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
307 			unsigned long arg);
308 
309 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper);
310 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel);
311 int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper);
312 int drm_fb_helper_debug_enter(struct fb_info *info);
313 int drm_fb_helper_debug_leave(struct fb_info *info);
314 struct drm_display_mode *
315 drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector,
316 			int width, int height);
317 struct drm_display_mode *
318 drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn);
319 
320 int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper, struct drm_connector *connector);
321 int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
322 				       struct drm_connector *connector);
323 
324 int drm_fb_helper_fbdev_setup(struct drm_device *dev,
325 			      struct drm_fb_helper *fb_helper,
326 			      const struct drm_fb_helper_funcs *funcs,
327 			      unsigned int preferred_bpp,
328 			      unsigned int max_conn_count);
329 void drm_fb_helper_fbdev_teardown(struct drm_device *dev);
330 
331 void drm_fb_helper_lastclose(struct drm_device *dev);
332 void drm_fb_helper_output_poll_changed(struct drm_device *dev);
333 #else
334 static inline void drm_fb_helper_prepare(struct drm_device *dev,
335 					struct drm_fb_helper *helper,
336 					const struct drm_fb_helper_funcs *funcs)
337 {
338 }
339 
340 static inline int drm_fb_helper_init(struct drm_device *dev,
341 		       struct drm_fb_helper *helper,
342 		       int max_conn)
343 {
344 	/* So drivers can use it to free the struct */
345 	helper->dev = dev;
346 	dev->fb_helper = helper;
347 
348 	return 0;
349 }
350 
351 static inline void drm_fb_helper_fini(struct drm_fb_helper *helper)
352 {
353 	if (helper && helper->dev)
354 		helper->dev->fb_helper = NULL;
355 }
356 
357 static inline int drm_fb_helper_blank(int blank, struct fb_info *info)
358 {
359 	return 0;
360 }
361 
362 static inline int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
363 					    struct fb_info *info)
364 {
365 	return 0;
366 }
367 
368 static inline int drm_fb_helper_set_par(struct fb_info *info)
369 {
370 	return 0;
371 }
372 
373 static inline int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
374 					  struct fb_info *info)
375 {
376 	return 0;
377 }
378 
379 static inline int
380 drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
381 {
382 	return 0;
383 }
384 
385 static inline struct fb_info *
386 drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper)
387 {
388 	return NULL;
389 }
390 
391 static inline void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper)
392 {
393 }
394 
395 static inline void drm_fb_helper_fill_var(struct fb_info *info,
396 					  struct drm_fb_helper *fb_helper,
397 					  uint32_t fb_width, uint32_t fb_height)
398 {
399 }
400 
401 static inline void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
402 					  uint32_t depth)
403 {
404 }
405 
406 static inline int drm_fb_helper_setcmap(struct fb_cmap *cmap,
407 					struct fb_info *info)
408 {
409 	return 0;
410 }
411 
412 static inline int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
413 				      unsigned long arg)
414 {
415 	return 0;
416 }
417 
418 static inline void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper)
419 {
420 }
421 
422 static inline void drm_fb_helper_deferred_io(struct fb_info *info,
423 					     struct list_head *pagelist)
424 {
425 }
426 
427 static inline int drm_fb_helper_defio_init(struct drm_fb_helper *fb_helper)
428 {
429 	return -ENODEV;
430 }
431 
432 static inline ssize_t drm_fb_helper_sys_read(struct fb_info *info,
433 					     char __user *buf, size_t count,
434 					     loff_t *ppos)
435 {
436 	return -ENODEV;
437 }
438 
439 static inline ssize_t drm_fb_helper_sys_write(struct fb_info *info,
440 					      const char __user *buf,
441 					      size_t count, loff_t *ppos)
442 {
443 	return -ENODEV;
444 }
445 
446 static inline void drm_fb_helper_sys_fillrect(struct fb_info *info,
447 					      const struct fb_fillrect *rect)
448 {
449 }
450 
451 static inline void drm_fb_helper_sys_copyarea(struct fb_info *info,
452 					      const struct fb_copyarea *area)
453 {
454 }
455 
456 static inline void drm_fb_helper_sys_imageblit(struct fb_info *info,
457 					       const struct fb_image *image)
458 {
459 }
460 
461 static inline void drm_fb_helper_cfb_fillrect(struct fb_info *info,
462 					      const struct fb_fillrect *rect)
463 {
464 }
465 
466 static inline void drm_fb_helper_cfb_copyarea(struct fb_info *info,
467 					      const struct fb_copyarea *area)
468 {
469 }
470 
471 static inline void drm_fb_helper_cfb_imageblit(struct fb_info *info,
472 					       const struct fb_image *image)
473 {
474 }
475 
476 static inline void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper,
477 					     bool suspend)
478 {
479 }
480 
481 static inline void
482 drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper, bool suspend)
483 {
484 }
485 
486 static inline int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
487 {
488 	return 0;
489 }
490 
491 static inline int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper,
492 					       int bpp_sel)
493 {
494 	return 0;
495 }
496 
497 static inline int
498 drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
499 {
500 	return 0;
501 }
502 
503 static inline int drm_fb_helper_debug_enter(struct fb_info *info)
504 {
505 	return 0;
506 }
507 
508 static inline int drm_fb_helper_debug_leave(struct fb_info *info)
509 {
510 	return 0;
511 }
512 
513 static inline struct drm_display_mode *
514 drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector,
515 		       int width, int height)
516 {
517 	return NULL;
518 }
519 
520 static inline struct drm_display_mode *
521 drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
522 		      int width, int height)
523 {
524 	return NULL;
525 }
526 
527 static inline int
528 drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper,
529 				struct drm_connector *connector)
530 {
531 	return 0;
532 }
533 
534 static inline int
535 drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
536 				   struct drm_connector *connector)
537 {
538 	return 0;
539 }
540 
541 static inline int
542 drm_fb_helper_fbdev_setup(struct drm_device *dev,
543 			  struct drm_fb_helper *fb_helper,
544 			  const struct drm_fb_helper_funcs *funcs,
545 			  unsigned int preferred_bpp,
546 			  unsigned int max_conn_count)
547 {
548 	/* So drivers can use it to free the struct */
549 	dev->fb_helper = fb_helper;
550 
551 	return 0;
552 }
553 
554 static inline void drm_fb_helper_fbdev_teardown(struct drm_device *dev)
555 {
556 	dev->fb_helper = NULL;
557 }
558 
559 static inline void drm_fb_helper_lastclose(struct drm_device *dev)
560 {
561 }
562 
563 static inline void drm_fb_helper_output_poll_changed(struct drm_device *dev)
564 {
565 }
566 
567 #endif
568 
569 static inline int
570 drm_fb_helper_remove_conflicting_framebuffers(struct apertures_struct *a,
571 					      const char *name, bool primary)
572 {
573 #if IS_REACHABLE(CONFIG_FB)
574 	return remove_conflicting_framebuffers(a, name, primary);
575 #else
576 	return 0;
577 #endif
578 }
579 
580 #endif
581