xref: /openbmc/linux/include/drm/drm_fb_helper.h (revision e7c5c29a)
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_clip_rect;
34 struct drm_fb_helper;
35 
36 #include <linux/fb.h>
37 
38 #include <drm/drm_client.h>
39 
40 enum mode_set_atomic {
41 	LEAVE_ATOMIC_MODE_SET,
42 	ENTER_ATOMIC_MODE_SET,
43 };
44 
45 /**
46  * struct drm_fb_helper_surface_size - describes fbdev size and scanout surface size
47  * @fb_width: fbdev width
48  * @fb_height: fbdev height
49  * @surface_width: scanout buffer width
50  * @surface_height: scanout buffer height
51  * @surface_bpp: scanout buffer bpp
52  * @surface_depth: scanout buffer depth
53  *
54  * Note that the scanout surface width/height may be larger than the fbdev
55  * width/height.  In case of multiple displays, the scanout surface is sized
56  * according to the largest width/height (so it is large enough for all CRTCs
57  * to scanout).  But the fbdev width/height is sized to the minimum width/
58  * height of all the displays.  This ensures that fbcon fits on the smallest
59  * of the attached displays. fb_width/fb_height is used by
60  * drm_fb_helper_fill_info() to fill out the &fb_info.var structure.
61  */
62 struct drm_fb_helper_surface_size {
63 	u32 fb_width;
64 	u32 fb_height;
65 	u32 surface_width;
66 	u32 surface_height;
67 	u32 surface_bpp;
68 	u32 surface_depth;
69 };
70 
71 /**
72  * struct drm_fb_helper_funcs - driver callbacks for the fbdev emulation library
73  *
74  * Driver callbacks used by the fbdev emulation helper library.
75  */
76 struct drm_fb_helper_funcs {
77 	/**
78 	 * @fb_probe:
79 	 *
80 	 * Driver callback to allocate and initialize the fbdev info structure.
81 	 * Furthermore it also needs to allocate the DRM framebuffer used to
82 	 * back the fbdev.
83 	 *
84 	 * This callback is mandatory.
85 	 *
86 	 * RETURNS:
87 	 *
88 	 * The driver should return 0 on success and a negative error code on
89 	 * failure.
90 	 */
91 	int (*fb_probe)(struct drm_fb_helper *helper,
92 			struct drm_fb_helper_surface_size *sizes);
93 
94 	/**
95 	 * @fb_dirty:
96 	 *
97 	 * Driver callback to update the framebuffer memory. If set, fbdev
98 	 * emulation will invoke this callback in regular intervals after
99 	 * the framebuffer has been written.
100 	 *
101 	 * This callback is optional.
102 	 *
103 	 * Returns:
104 	 * 0 on success, or an error code otherwise.
105 	 */
106 	int (*fb_dirty)(struct drm_fb_helper *helper, struct drm_clip_rect *clip);
107 };
108 
109 /**
110  * struct drm_fb_helper - main structure to emulate fbdev on top of KMS
111  * @fb: Scanout framebuffer object
112  * @dev: DRM device
113  * @funcs: driver callbacks for fb helper
114  * @info: emulated fbdev device info struct
115  * @pseudo_palette: fake palette of 16 colors
116  * @damage_clip: clip rectangle used with deferred_io to accumulate damage to
117  *                the screen buffer
118  * @damage_lock: spinlock protecting @damage_clip
119  * @damage_work: worker used to flush the framebuffer
120  * @resume_work: worker used during resume if the console lock is already taken
121  *
122  * This is the main structure used by the fbdev helpers. Drivers supporting
123  * fbdev emulation should embedded this into their overall driver structure.
124  * Drivers must also fill out a &struct drm_fb_helper_funcs with a few
125  * operations.
126  */
127 struct drm_fb_helper {
128 	/**
129 	 * @client:
130 	 *
131 	 * DRM client used by the generic fbdev emulation.
132 	 */
133 	struct drm_client_dev client;
134 
135 	/**
136 	 * @buffer:
137 	 *
138 	 * Framebuffer used by the generic fbdev emulation.
139 	 */
140 	struct drm_client_buffer *buffer;
141 
142 	struct drm_framebuffer *fb;
143 	struct drm_device *dev;
144 	const struct drm_fb_helper_funcs *funcs;
145 	struct fb_info *info;
146 	u32 pseudo_palette[17];
147 	struct drm_clip_rect damage_clip;
148 	spinlock_t damage_lock;
149 	struct work_struct damage_work;
150 	struct work_struct resume_work;
151 
152 	/**
153 	 * @lock:
154 	 *
155 	 * Top-level FBDEV helper lock. This protects all internal data
156 	 * structures and lists, such as @connector_info and @crtc_info.
157 	 *
158 	 * FIXME: fbdev emulation locking is a mess and long term we want to
159 	 * protect all helper internal state with this lock as well as reduce
160 	 * core KMS locking as much as possible.
161 	 */
162 	struct mutex lock;
163 
164 	/**
165 	 * @kernel_fb_list:
166 	 *
167 	 * Entry on the global kernel_fb_helper_list, used for kgdb entry/exit.
168 	 */
169 	struct list_head kernel_fb_list;
170 
171 	/**
172 	 * @delayed_hotplug:
173 	 *
174 	 * A hotplug was received while fbdev wasn't in control of the DRM
175 	 * device, i.e. another KMS master was active. The output configuration
176 	 * needs to be reprobe when fbdev is in control again.
177 	 */
178 	bool delayed_hotplug;
179 
180 	/**
181 	 * @deferred_setup:
182 	 *
183 	 * If no outputs are connected (disconnected or unknown) the FB helper
184 	 * code will defer setup until at least one of the outputs shows up.
185 	 * This field keeps track of the status so that setup can be retried
186 	 * at every hotplug event until it succeeds eventually.
187 	 *
188 	 * Protected by @lock.
189 	 */
190 	bool deferred_setup;
191 
192 	/**
193 	 * @preferred_bpp:
194 	 *
195 	 * Temporary storage for the driver's preferred BPP setting passed to
196 	 * FB helper initialization. This needs to be tracked so that deferred
197 	 * FB helper setup can pass this on.
198 	 *
199 	 * See also: @deferred_setup
200 	 */
201 	int preferred_bpp;
202 
203 	bool hint_leak_smem_start;
204 };
205 
206 static inline struct drm_fb_helper *
207 drm_fb_helper_from_client(struct drm_client_dev *client)
208 {
209 	return container_of(client, struct drm_fb_helper, client);
210 }
211 
212 /**
213  * define DRM_FB_HELPER_DEFAULT_OPS - helper define for drm drivers
214  *
215  * Helper define to register default implementations of drm_fb_helper
216  * functions. To be used in struct fb_ops of drm drivers.
217  */
218 #define DRM_FB_HELPER_DEFAULT_OPS \
219 	.fb_check_var	= drm_fb_helper_check_var, \
220 	.fb_set_par	= drm_fb_helper_set_par, \
221 	.fb_setcmap	= drm_fb_helper_setcmap, \
222 	.fb_blank	= drm_fb_helper_blank, \
223 	.fb_pan_display	= drm_fb_helper_pan_display, \
224 	.fb_debug_enter = drm_fb_helper_debug_enter, \
225 	.fb_debug_leave = drm_fb_helper_debug_leave, \
226 	.fb_ioctl	= drm_fb_helper_ioctl
227 
228 #ifdef CONFIG_DRM_FBDEV_EMULATION
229 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
230 			   const struct drm_fb_helper_funcs *funcs);
231 int drm_fb_helper_init(struct drm_device *dev, struct drm_fb_helper *helper);
232 void drm_fb_helper_fini(struct drm_fb_helper *helper);
233 int drm_fb_helper_blank(int blank, struct fb_info *info);
234 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
235 			      struct fb_info *info);
236 int drm_fb_helper_set_par(struct fb_info *info);
237 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
238 			    struct fb_info *info);
239 
240 int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper);
241 
242 struct fb_info *drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper);
243 void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper);
244 void drm_fb_helper_fill_info(struct fb_info *info,
245 			     struct drm_fb_helper *fb_helper,
246 			     struct drm_fb_helper_surface_size *sizes);
247 
248 void drm_fb_helper_deferred_io(struct fb_info *info, struct list_head *pagereflist);
249 
250 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
251 			       size_t count, loff_t *ppos);
252 ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
253 				size_t count, loff_t *ppos);
254 
255 void drm_fb_helper_sys_fillrect(struct fb_info *info,
256 				const struct fb_fillrect *rect);
257 void drm_fb_helper_sys_copyarea(struct fb_info *info,
258 				const struct fb_copyarea *area);
259 void drm_fb_helper_sys_imageblit(struct fb_info *info,
260 				 const struct fb_image *image);
261 
262 ssize_t drm_fb_helper_cfb_read(struct fb_info *info, char __user *buf,
263 			       size_t count, loff_t *ppos);
264 ssize_t drm_fb_helper_cfb_write(struct fb_info *info, const char __user *buf,
265 				size_t count, loff_t *ppos);
266 
267 void drm_fb_helper_cfb_fillrect(struct fb_info *info,
268 				const struct fb_fillrect *rect);
269 void drm_fb_helper_cfb_copyarea(struct fb_info *info,
270 				const struct fb_copyarea *area);
271 void drm_fb_helper_cfb_imageblit(struct fb_info *info,
272 				 const struct fb_image *image);
273 
274 void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend);
275 void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
276 					bool suspend);
277 
278 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info);
279 
280 int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
281 			unsigned long arg);
282 
283 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper);
284 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel);
285 int drm_fb_helper_debug_enter(struct fb_info *info);
286 int drm_fb_helper_debug_leave(struct fb_info *info);
287 
288 void drm_fb_helper_lastclose(struct drm_device *dev);
289 void drm_fb_helper_output_poll_changed(struct drm_device *dev);
290 
291 void drm_fbdev_generic_setup(struct drm_device *dev,
292 			     unsigned int preferred_bpp);
293 #else
294 static inline void drm_fb_helper_prepare(struct drm_device *dev,
295 					struct drm_fb_helper *helper,
296 					const struct drm_fb_helper_funcs *funcs)
297 {
298 }
299 
300 static inline int drm_fb_helper_init(struct drm_device *dev,
301 		       struct drm_fb_helper *helper)
302 {
303 	/* So drivers can use it to free the struct */
304 	helper->dev = dev;
305 	dev->fb_helper = helper;
306 
307 	return 0;
308 }
309 
310 static inline void drm_fb_helper_fini(struct drm_fb_helper *helper)
311 {
312 	if (helper && helper->dev)
313 		helper->dev->fb_helper = NULL;
314 }
315 
316 static inline int drm_fb_helper_blank(int blank, struct fb_info *info)
317 {
318 	return 0;
319 }
320 
321 static inline int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
322 					    struct fb_info *info)
323 {
324 	return 0;
325 }
326 
327 static inline int drm_fb_helper_set_par(struct fb_info *info)
328 {
329 	return 0;
330 }
331 
332 static inline int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
333 					  struct fb_info *info)
334 {
335 	return 0;
336 }
337 
338 static inline int
339 drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
340 {
341 	return 0;
342 }
343 
344 static inline struct fb_info *
345 drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper)
346 {
347 	return NULL;
348 }
349 
350 static inline void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper)
351 {
352 }
353 
354 static inline void
355 drm_fb_helper_fill_info(struct fb_info *info,
356 			struct drm_fb_helper *fb_helper,
357 			struct drm_fb_helper_surface_size *sizes)
358 {
359 }
360 
361 static inline int drm_fb_helper_setcmap(struct fb_cmap *cmap,
362 					struct fb_info *info)
363 {
364 	return 0;
365 }
366 
367 static inline int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
368 				      unsigned long arg)
369 {
370 	return 0;
371 }
372 
373 static inline void drm_fb_helper_deferred_io(struct fb_info *info,
374 					     struct list_head *pagelist)
375 {
376 }
377 
378 static inline int drm_fb_helper_defio_init(struct drm_fb_helper *fb_helper)
379 {
380 	return -ENODEV;
381 }
382 
383 static inline ssize_t drm_fb_helper_sys_read(struct fb_info *info,
384 					     char __user *buf, size_t count,
385 					     loff_t *ppos)
386 {
387 	return -ENODEV;
388 }
389 
390 static inline ssize_t drm_fb_helper_sys_write(struct fb_info *info,
391 					      const char __user *buf,
392 					      size_t count, loff_t *ppos)
393 {
394 	return -ENODEV;
395 }
396 
397 static inline void drm_fb_helper_sys_fillrect(struct fb_info *info,
398 					      const struct fb_fillrect *rect)
399 {
400 }
401 
402 static inline void drm_fb_helper_sys_copyarea(struct fb_info *info,
403 					      const struct fb_copyarea *area)
404 {
405 }
406 
407 static inline void drm_fb_helper_sys_imageblit(struct fb_info *info,
408 					       const struct fb_image *image)
409 {
410 }
411 
412 static inline ssize_t drm_fb_helper_cfb_read(struct fb_info *info, char __user *buf,
413 					     size_t count, loff_t *ppos)
414 {
415 	return -ENODEV;
416 }
417 
418 static inline ssize_t drm_fb_helper_cfb_write(struct fb_info *info, const char __user *buf,
419 					      size_t count, loff_t *ppos)
420 {
421 	return -ENODEV;
422 }
423 
424 static inline void drm_fb_helper_cfb_fillrect(struct fb_info *info,
425 					      const struct fb_fillrect *rect)
426 {
427 }
428 
429 static inline void drm_fb_helper_cfb_copyarea(struct fb_info *info,
430 					      const struct fb_copyarea *area)
431 {
432 }
433 
434 static inline void drm_fb_helper_cfb_imageblit(struct fb_info *info,
435 					       const struct fb_image *image)
436 {
437 }
438 
439 static inline void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper,
440 					     bool suspend)
441 {
442 }
443 
444 static inline void
445 drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper, bool suspend)
446 {
447 }
448 
449 static inline int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
450 {
451 	return 0;
452 }
453 
454 static inline int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper,
455 					       int bpp_sel)
456 {
457 	return 0;
458 }
459 
460 static inline int drm_fb_helper_debug_enter(struct fb_info *info)
461 {
462 	return 0;
463 }
464 
465 static inline int drm_fb_helper_debug_leave(struct fb_info *info)
466 {
467 	return 0;
468 }
469 
470 static inline void drm_fb_helper_lastclose(struct drm_device *dev)
471 {
472 }
473 
474 static inline void drm_fb_helper_output_poll_changed(struct drm_device *dev)
475 {
476 }
477 
478 static inline void
479 drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp)
480 {
481 }
482 
483 #endif
484 
485 #endif
486