xref: /openbmc/linux/include/drm/drm_fb_helper.h (revision 3d8853dd)
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 /**
41  * struct drm_fb_helper_surface_size - describes fbdev size and scanout surface size
42  * @fb_width: fbdev width
43  * @fb_height: fbdev height
44  * @surface_width: scanout buffer width
45  * @surface_height: scanout buffer height
46  * @surface_bpp: scanout buffer bpp
47  * @surface_depth: scanout buffer depth
48  *
49  * Note that the scanout surface width/height may be larger than the fbdev
50  * width/height.  In case of multiple displays, the scanout surface is sized
51  * according to the largest width/height (so it is large enough for all CRTCs
52  * to scanout).  But the fbdev width/height is sized to the minimum width/
53  * height of all the displays.  This ensures that fbcon fits on the smallest
54  * of the attached displays. fb_width/fb_height is used by
55  * drm_fb_helper_fill_info() to fill out the &fb_info.var structure.
56  */
57 struct drm_fb_helper_surface_size {
58 	u32 fb_width;
59 	u32 fb_height;
60 	u32 surface_width;
61 	u32 surface_height;
62 	u32 surface_bpp;
63 	u32 surface_depth;
64 };
65 
66 /**
67  * struct drm_fb_helper_funcs - driver callbacks for the fbdev emulation library
68  *
69  * Driver callbacks used by the fbdev emulation helper library.
70  */
71 struct drm_fb_helper_funcs {
72 	/**
73 	 * @fb_probe:
74 	 *
75 	 * Driver callback to allocate and initialize the fbdev info structure.
76 	 * Furthermore it also needs to allocate the DRM framebuffer used to
77 	 * back the fbdev.
78 	 *
79 	 * This callback is mandatory.
80 	 *
81 	 * RETURNS:
82 	 *
83 	 * The driver should return 0 on success and a negative error code on
84 	 * failure.
85 	 */
86 	int (*fb_probe)(struct drm_fb_helper *helper,
87 			struct drm_fb_helper_surface_size *sizes);
88 
89 	/**
90 	 * @fb_dirty:
91 	 *
92 	 * Driver callback to update the framebuffer memory. If set, fbdev
93 	 * emulation will invoke this callback in regular intervals after
94 	 * the framebuffer has been written.
95 	 *
96 	 * This callback is optional.
97 	 *
98 	 * Returns:
99 	 * 0 on success, or an error code otherwise.
100 	 */
101 	int (*fb_dirty)(struct drm_fb_helper *helper, struct drm_clip_rect *clip);
102 };
103 
104 /**
105  * struct drm_fb_helper - main structure to emulate fbdev on top of KMS
106  * @fb: Scanout framebuffer object
107  * @dev: DRM device
108  * @funcs: driver callbacks for fb helper
109  * @info: emulated fbdev device info struct
110  * @pseudo_palette: fake palette of 16 colors
111  * @damage_clip: clip rectangle used with deferred_io to accumulate damage to
112  *                the screen buffer
113  * @damage_lock: spinlock protecting @damage_clip
114  * @damage_work: worker used to flush the framebuffer
115  * @resume_work: worker used during resume if the console lock is already taken
116  *
117  * This is the main structure used by the fbdev helpers. Drivers supporting
118  * fbdev emulation should embedded this into their overall driver structure.
119  * Drivers must also fill out a &struct drm_fb_helper_funcs with a few
120  * operations.
121  */
122 struct drm_fb_helper {
123 	/**
124 	 * @client:
125 	 *
126 	 * DRM client used by the generic fbdev emulation.
127 	 */
128 	struct drm_client_dev client;
129 
130 	/**
131 	 * @buffer:
132 	 *
133 	 * Framebuffer used by the generic fbdev emulation.
134 	 */
135 	struct drm_client_buffer *buffer;
136 
137 	struct drm_framebuffer *fb;
138 	struct drm_device *dev;
139 	const struct drm_fb_helper_funcs *funcs;
140 	struct fb_info *info;
141 	u32 pseudo_palette[17];
142 	struct drm_clip_rect damage_clip;
143 	spinlock_t damage_lock;
144 	struct work_struct damage_work;
145 	struct work_struct resume_work;
146 
147 	/**
148 	 * @lock:
149 	 *
150 	 * Top-level FBDEV helper lock. This protects all internal data
151 	 * structures and lists, such as @connector_info and @crtc_info.
152 	 *
153 	 * FIXME: fbdev emulation locking is a mess and long term we want to
154 	 * protect all helper internal state with this lock as well as reduce
155 	 * core KMS locking as much as possible.
156 	 */
157 	struct mutex lock;
158 
159 	/**
160 	 * @kernel_fb_list:
161 	 *
162 	 * Entry on the global kernel_fb_helper_list, used for kgdb entry/exit.
163 	 */
164 	struct list_head kernel_fb_list;
165 
166 	/**
167 	 * @delayed_hotplug:
168 	 *
169 	 * A hotplug was received while fbdev wasn't in control of the DRM
170 	 * device, i.e. another KMS master was active. The output configuration
171 	 * needs to be reprobe when fbdev is in control again.
172 	 */
173 	bool delayed_hotplug;
174 
175 	/**
176 	 * @deferred_setup:
177 	 *
178 	 * If no outputs are connected (disconnected or unknown) the FB helper
179 	 * code will defer setup until at least one of the outputs shows up.
180 	 * This field keeps track of the status so that setup can be retried
181 	 * at every hotplug event until it succeeds eventually.
182 	 *
183 	 * Protected by @lock.
184 	 */
185 	bool deferred_setup;
186 
187 	/**
188 	 * @preferred_bpp:
189 	 *
190 	 * Temporary storage for the driver's preferred BPP setting passed to
191 	 * FB helper initialization. This needs to be tracked so that deferred
192 	 * FB helper setup can pass this on.
193 	 *
194 	 * See also: @deferred_setup
195 	 */
196 	int preferred_bpp;
197 
198 	/**
199 	 * @hint_leak_smem_start:
200 	 *
201 	 * Hint to the fbdev emulation to store the framebuffer's physical
202 	 * address in struct &fb_info.fix.smem_start. If the hint is unset,
203 	 * the smem_start field should always be cleared to zero.
204 	 */
205 	bool hint_leak_smem_start;
206 };
207 
208 static inline struct drm_fb_helper *
209 drm_fb_helper_from_client(struct drm_client_dev *client)
210 {
211 	return container_of(client, struct drm_fb_helper, client);
212 }
213 
214 /**
215  * define DRM_FB_HELPER_DEFAULT_OPS - helper define for drm drivers
216  *
217  * Helper define to register default implementations of drm_fb_helper
218  * functions. To be used in struct fb_ops of drm drivers.
219  */
220 #define DRM_FB_HELPER_DEFAULT_OPS \
221 	.fb_check_var	= drm_fb_helper_check_var, \
222 	.fb_set_par	= drm_fb_helper_set_par, \
223 	.fb_setcmap	= drm_fb_helper_setcmap, \
224 	.fb_blank	= drm_fb_helper_blank, \
225 	.fb_pan_display	= drm_fb_helper_pan_display, \
226 	.fb_debug_enter = drm_fb_helper_debug_enter, \
227 	.fb_debug_leave = drm_fb_helper_debug_leave, \
228 	.fb_ioctl	= drm_fb_helper_ioctl
229 
230 #ifdef CONFIG_DRM_FBDEV_EMULATION
231 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
232 			   const struct drm_fb_helper_funcs *funcs);
233 int drm_fb_helper_init(struct drm_device *dev, struct drm_fb_helper *helper);
234 void drm_fb_helper_fini(struct drm_fb_helper *helper);
235 int drm_fb_helper_blank(int blank, struct fb_info *info);
236 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
237 			      struct fb_info *info);
238 int drm_fb_helper_set_par(struct fb_info *info);
239 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
240 			    struct fb_info *info);
241 
242 int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper);
243 
244 struct fb_info *drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper);
245 void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper);
246 void drm_fb_helper_fill_info(struct fb_info *info,
247 			     struct drm_fb_helper *fb_helper,
248 			     struct drm_fb_helper_surface_size *sizes);
249 
250 void drm_fb_helper_deferred_io(struct fb_info *info, struct list_head *pagereflist);
251 
252 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
253 			       size_t count, loff_t *ppos);
254 ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
255 				size_t count, loff_t *ppos);
256 
257 void drm_fb_helper_sys_fillrect(struct fb_info *info,
258 				const struct fb_fillrect *rect);
259 void drm_fb_helper_sys_copyarea(struct fb_info *info,
260 				const struct fb_copyarea *area);
261 void drm_fb_helper_sys_imageblit(struct fb_info *info,
262 				 const struct fb_image *image);
263 
264 ssize_t drm_fb_helper_cfb_read(struct fb_info *info, char __user *buf,
265 			       size_t count, loff_t *ppos);
266 ssize_t drm_fb_helper_cfb_write(struct fb_info *info, const char __user *buf,
267 				size_t count, loff_t *ppos);
268 
269 void drm_fb_helper_cfb_fillrect(struct fb_info *info,
270 				const struct fb_fillrect *rect);
271 void drm_fb_helper_cfb_copyarea(struct fb_info *info,
272 				const struct fb_copyarea *area);
273 void drm_fb_helper_cfb_imageblit(struct fb_info *info,
274 				 const struct fb_image *image);
275 
276 void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend);
277 void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
278 					bool suspend);
279 
280 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info);
281 
282 int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
283 			unsigned long arg);
284 
285 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper);
286 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel);
287 int drm_fb_helper_debug_enter(struct fb_info *info);
288 int drm_fb_helper_debug_leave(struct fb_info *info);
289 
290 void drm_fb_helper_lastclose(struct drm_device *dev);
291 void drm_fb_helper_output_poll_changed(struct drm_device *dev);
292 #else
293 static inline void drm_fb_helper_prepare(struct drm_device *dev,
294 					struct drm_fb_helper *helper,
295 					const struct drm_fb_helper_funcs *funcs)
296 {
297 }
298 
299 static inline int drm_fb_helper_init(struct drm_device *dev,
300 		       struct drm_fb_helper *helper)
301 {
302 	/* So drivers can use it to free the struct */
303 	helper->dev = dev;
304 	dev->fb_helper = helper;
305 
306 	return 0;
307 }
308 
309 static inline void drm_fb_helper_fini(struct drm_fb_helper *helper)
310 {
311 	if (helper && helper->dev)
312 		helper->dev->fb_helper = NULL;
313 }
314 
315 static inline int drm_fb_helper_blank(int blank, struct fb_info *info)
316 {
317 	return 0;
318 }
319 
320 static inline int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
321 					    struct fb_info *info)
322 {
323 	return 0;
324 }
325 
326 static inline int drm_fb_helper_set_par(struct fb_info *info)
327 {
328 	return 0;
329 }
330 
331 static inline int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
332 					  struct fb_info *info)
333 {
334 	return 0;
335 }
336 
337 static inline int
338 drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
339 {
340 	return 0;
341 }
342 
343 static inline struct fb_info *
344 drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper)
345 {
346 	return NULL;
347 }
348 
349 static inline void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper)
350 {
351 }
352 
353 static inline void
354 drm_fb_helper_fill_info(struct fb_info *info,
355 			struct drm_fb_helper *fb_helper,
356 			struct drm_fb_helper_surface_size *sizes)
357 {
358 }
359 
360 static inline int drm_fb_helper_setcmap(struct fb_cmap *cmap,
361 					struct fb_info *info)
362 {
363 	return 0;
364 }
365 
366 static inline int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
367 				      unsigned long arg)
368 {
369 	return 0;
370 }
371 
372 static inline void drm_fb_helper_deferred_io(struct fb_info *info,
373 					     struct list_head *pagelist)
374 {
375 }
376 
377 static inline int drm_fb_helper_defio_init(struct drm_fb_helper *fb_helper)
378 {
379 	return -ENODEV;
380 }
381 
382 static inline ssize_t drm_fb_helper_sys_read(struct fb_info *info,
383 					     char __user *buf, size_t count,
384 					     loff_t *ppos)
385 {
386 	return -ENODEV;
387 }
388 
389 static inline ssize_t drm_fb_helper_sys_write(struct fb_info *info,
390 					      const char __user *buf,
391 					      size_t count, loff_t *ppos)
392 {
393 	return -ENODEV;
394 }
395 
396 static inline void drm_fb_helper_sys_fillrect(struct fb_info *info,
397 					      const struct fb_fillrect *rect)
398 {
399 }
400 
401 static inline void drm_fb_helper_sys_copyarea(struct fb_info *info,
402 					      const struct fb_copyarea *area)
403 {
404 }
405 
406 static inline void drm_fb_helper_sys_imageblit(struct fb_info *info,
407 					       const struct fb_image *image)
408 {
409 }
410 
411 static inline ssize_t drm_fb_helper_cfb_read(struct fb_info *info, char __user *buf,
412 					     size_t count, loff_t *ppos)
413 {
414 	return -ENODEV;
415 }
416 
417 static inline ssize_t drm_fb_helper_cfb_write(struct fb_info *info, const char __user *buf,
418 					      size_t count, loff_t *ppos)
419 {
420 	return -ENODEV;
421 }
422 
423 static inline void drm_fb_helper_cfb_fillrect(struct fb_info *info,
424 					      const struct fb_fillrect *rect)
425 {
426 }
427 
428 static inline void drm_fb_helper_cfb_copyarea(struct fb_info *info,
429 					      const struct fb_copyarea *area)
430 {
431 }
432 
433 static inline void drm_fb_helper_cfb_imageblit(struct fb_info *info,
434 					       const struct fb_image *image)
435 {
436 }
437 
438 static inline void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper,
439 					     bool suspend)
440 {
441 }
442 
443 static inline void
444 drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper, bool suspend)
445 {
446 }
447 
448 static inline int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
449 {
450 	return 0;
451 }
452 
453 static inline int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper,
454 					       int bpp_sel)
455 {
456 	return 0;
457 }
458 
459 static inline int drm_fb_helper_debug_enter(struct fb_info *info)
460 {
461 	return 0;
462 }
463 
464 static inline int drm_fb_helper_debug_leave(struct fb_info *info)
465 {
466 	return 0;
467 }
468 
469 static inline void drm_fb_helper_lastclose(struct drm_device *dev)
470 {
471 }
472 
473 static inline void drm_fb_helper_output_poll_changed(struct drm_device *dev)
474 {
475 }
476 #endif
477 
478 #endif
479