xref: /openbmc/linux/include/drm/drm_fb_helper.h (revision c059ee9d)
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_client.h>
36 #include <drm/drm_crtc.h>
37 #include <drm/drm_device.h>
38 #include <linux/kgdb.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 /**
96  * struct drm_fb_helper - main structure to emulate fbdev on top of KMS
97  * @fb: Scanout framebuffer object
98  * @dev: DRM device
99  * @funcs: driver callbacks for fb helper
100  * @fbdev: emulated fbdev device info struct
101  * @pseudo_palette: fake palette of 16 colors
102  * @damage_clip: clip rectangle used with deferred_io to accumulate damage to
103  *                the screen buffer
104  * @damage_lock: spinlock protecting @damage_clip
105  * @damage_work: worker used to flush the framebuffer
106  * @resume_work: worker used during resume if the console lock is already taken
107  *
108  * This is the main structure used by the fbdev helpers. Drivers supporting
109  * fbdev emulation should embedded this into their overall driver structure.
110  * Drivers must also fill out a &struct drm_fb_helper_funcs with a few
111  * operations.
112  */
113 struct drm_fb_helper {
114 	/**
115 	 * @client:
116 	 *
117 	 * DRM client used by the generic fbdev emulation.
118 	 */
119 	struct drm_client_dev client;
120 
121 	/**
122 	 * @buffer:
123 	 *
124 	 * Framebuffer used by the generic fbdev emulation.
125 	 */
126 	struct drm_client_buffer *buffer;
127 
128 	struct drm_framebuffer *fb;
129 	struct drm_device *dev;
130 	const struct drm_fb_helper_funcs *funcs;
131 	struct fb_info *fbdev;
132 	u32 pseudo_palette[17];
133 	struct drm_clip_rect damage_clip;
134 	spinlock_t damage_lock;
135 	struct work_struct damage_work;
136 	struct work_struct resume_work;
137 
138 	/**
139 	 * @lock:
140 	 *
141 	 * Top-level FBDEV helper lock. This protects all internal data
142 	 * structures and lists, such as @connector_info and @crtc_info.
143 	 *
144 	 * FIXME: fbdev emulation locking is a mess and long term we want to
145 	 * protect all helper internal state with this lock as well as reduce
146 	 * core KMS locking as much as possible.
147 	 */
148 	struct mutex lock;
149 
150 	/**
151 	 * @kernel_fb_list:
152 	 *
153 	 * Entry on the global kernel_fb_helper_list, used for kgdb entry/exit.
154 	 */
155 	struct list_head kernel_fb_list;
156 
157 	/**
158 	 * @delayed_hotplug:
159 	 *
160 	 * A hotplug was received while fbdev wasn't in control of the DRM
161 	 * device, i.e. another KMS master was active. The output configuration
162 	 * needs to be reprobe when fbdev is in control again.
163 	 */
164 	bool delayed_hotplug;
165 
166 	/**
167 	 * @deferred_setup:
168 	 *
169 	 * If no outputs are connected (disconnected or unknown) the FB helper
170 	 * code will defer setup until at least one of the outputs shows up.
171 	 * This field keeps track of the status so that setup can be retried
172 	 * at every hotplug event until it succeeds eventually.
173 	 *
174 	 * Protected by @lock.
175 	 */
176 	bool deferred_setup;
177 
178 	/**
179 	 * @preferred_bpp:
180 	 *
181 	 * Temporary storage for the driver's preferred BPP setting passed to
182 	 * FB helper initialization. This needs to be tracked so that deferred
183 	 * FB helper setup can pass this on.
184 	 *
185 	 * See also: @deferred_setup
186 	 */
187 	int preferred_bpp;
188 };
189 
190 static inline struct drm_fb_helper *
191 drm_fb_helper_from_client(struct drm_client_dev *client)
192 {
193 	return container_of(client, struct drm_fb_helper, client);
194 }
195 
196 /**
197  * define DRM_FB_HELPER_DEFAULT_OPS - helper define for drm drivers
198  *
199  * Helper define to register default implementations of drm_fb_helper
200  * functions. To be used in struct fb_ops of drm drivers.
201  */
202 #define DRM_FB_HELPER_DEFAULT_OPS \
203 	.fb_check_var	= drm_fb_helper_check_var, \
204 	.fb_set_par	= drm_fb_helper_set_par, \
205 	.fb_setcmap	= drm_fb_helper_setcmap, \
206 	.fb_blank	= drm_fb_helper_blank, \
207 	.fb_pan_display	= drm_fb_helper_pan_display, \
208 	.fb_debug_enter = drm_fb_helper_debug_enter, \
209 	.fb_debug_leave = drm_fb_helper_debug_leave, \
210 	.fb_ioctl	= drm_fb_helper_ioctl
211 
212 #ifdef CONFIG_DRM_FBDEV_EMULATION
213 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
214 			   const struct drm_fb_helper_funcs *funcs);
215 int drm_fb_helper_init(struct drm_device *dev, struct drm_fb_helper *helper);
216 void drm_fb_helper_fini(struct drm_fb_helper *helper);
217 int drm_fb_helper_blank(int blank, struct fb_info *info);
218 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
219 			      struct fb_info *info);
220 int drm_fb_helper_set_par(struct fb_info *info);
221 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
222 			    struct fb_info *info);
223 
224 int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper);
225 
226 struct fb_info *drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper);
227 void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper);
228 void drm_fb_helper_fill_info(struct fb_info *info,
229 			     struct drm_fb_helper *fb_helper,
230 			     struct drm_fb_helper_surface_size *sizes);
231 
232 void drm_fb_helper_deferred_io(struct fb_info *info, struct list_head *pagereflist);
233 
234 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
235 			       size_t count, loff_t *ppos);
236 ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
237 				size_t count, loff_t *ppos);
238 
239 void drm_fb_helper_sys_fillrect(struct fb_info *info,
240 				const struct fb_fillrect *rect);
241 void drm_fb_helper_sys_copyarea(struct fb_info *info,
242 				const struct fb_copyarea *area);
243 void drm_fb_helper_sys_imageblit(struct fb_info *info,
244 				 const struct fb_image *image);
245 
246 void drm_fb_helper_cfb_fillrect(struct fb_info *info,
247 				const struct fb_fillrect *rect);
248 void drm_fb_helper_cfb_copyarea(struct fb_info *info,
249 				const struct fb_copyarea *area);
250 void drm_fb_helper_cfb_imageblit(struct fb_info *info,
251 				 const struct fb_image *image);
252 
253 void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend);
254 void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
255 					bool suspend);
256 
257 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info);
258 
259 int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
260 			unsigned long arg);
261 
262 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper);
263 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel);
264 int drm_fb_helper_debug_enter(struct fb_info *info);
265 int drm_fb_helper_debug_leave(struct fb_info *info);
266 
267 void drm_fb_helper_lastclose(struct drm_device *dev);
268 void drm_fb_helper_output_poll_changed(struct drm_device *dev);
269 
270 void drm_fbdev_generic_setup(struct drm_device *dev,
271 			     unsigned int preferred_bpp);
272 #else
273 static inline void drm_fb_helper_prepare(struct drm_device *dev,
274 					struct drm_fb_helper *helper,
275 					const struct drm_fb_helper_funcs *funcs)
276 {
277 }
278 
279 static inline int drm_fb_helper_init(struct drm_device *dev,
280 		       struct drm_fb_helper *helper)
281 {
282 	/* So drivers can use it to free the struct */
283 	helper->dev = dev;
284 	dev->fb_helper = helper;
285 
286 	return 0;
287 }
288 
289 static inline void drm_fb_helper_fini(struct drm_fb_helper *helper)
290 {
291 	if (helper && helper->dev)
292 		helper->dev->fb_helper = NULL;
293 }
294 
295 static inline int drm_fb_helper_blank(int blank, struct fb_info *info)
296 {
297 	return 0;
298 }
299 
300 static inline int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
301 					    struct fb_info *info)
302 {
303 	return 0;
304 }
305 
306 static inline int drm_fb_helper_set_par(struct fb_info *info)
307 {
308 	return 0;
309 }
310 
311 static inline int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
312 					  struct fb_info *info)
313 {
314 	return 0;
315 }
316 
317 static inline int
318 drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
319 {
320 	return 0;
321 }
322 
323 static inline struct fb_info *
324 drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper)
325 {
326 	return NULL;
327 }
328 
329 static inline void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper)
330 {
331 }
332 
333 static inline void
334 drm_fb_helper_fill_info(struct fb_info *info,
335 			struct drm_fb_helper *fb_helper,
336 			struct drm_fb_helper_surface_size *sizes)
337 {
338 }
339 
340 static inline int drm_fb_helper_setcmap(struct fb_cmap *cmap,
341 					struct fb_info *info)
342 {
343 	return 0;
344 }
345 
346 static inline int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
347 				      unsigned long arg)
348 {
349 	return 0;
350 }
351 
352 static inline void drm_fb_helper_deferred_io(struct fb_info *info,
353 					     struct list_head *pagelist)
354 {
355 }
356 
357 static inline int drm_fb_helper_defio_init(struct drm_fb_helper *fb_helper)
358 {
359 	return -ENODEV;
360 }
361 
362 static inline ssize_t drm_fb_helper_sys_read(struct fb_info *info,
363 					     char __user *buf, size_t count,
364 					     loff_t *ppos)
365 {
366 	return -ENODEV;
367 }
368 
369 static inline ssize_t drm_fb_helper_sys_write(struct fb_info *info,
370 					      const char __user *buf,
371 					      size_t count, loff_t *ppos)
372 {
373 	return -ENODEV;
374 }
375 
376 static inline void drm_fb_helper_sys_fillrect(struct fb_info *info,
377 					      const struct fb_fillrect *rect)
378 {
379 }
380 
381 static inline void drm_fb_helper_sys_copyarea(struct fb_info *info,
382 					      const struct fb_copyarea *area)
383 {
384 }
385 
386 static inline void drm_fb_helper_sys_imageblit(struct fb_info *info,
387 					       const struct fb_image *image)
388 {
389 }
390 
391 static inline void drm_fb_helper_cfb_fillrect(struct fb_info *info,
392 					      const struct fb_fillrect *rect)
393 {
394 }
395 
396 static inline void drm_fb_helper_cfb_copyarea(struct fb_info *info,
397 					      const struct fb_copyarea *area)
398 {
399 }
400 
401 static inline void drm_fb_helper_cfb_imageblit(struct fb_info *info,
402 					       const struct fb_image *image)
403 {
404 }
405 
406 static inline void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper,
407 					     bool suspend)
408 {
409 }
410 
411 static inline void
412 drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper, bool suspend)
413 {
414 }
415 
416 static inline int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
417 {
418 	return 0;
419 }
420 
421 static inline int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper,
422 					       int bpp_sel)
423 {
424 	return 0;
425 }
426 
427 static inline int drm_fb_helper_debug_enter(struct fb_info *info)
428 {
429 	return 0;
430 }
431 
432 static inline int drm_fb_helper_debug_leave(struct fb_info *info)
433 {
434 	return 0;
435 }
436 
437 static inline void drm_fb_helper_lastclose(struct drm_device *dev)
438 {
439 }
440 
441 static inline void drm_fb_helper_output_poll_changed(struct drm_device *dev)
442 {
443 }
444 
445 static inline void
446 drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp)
447 {
448 }
449 
450 #endif
451 
452 #endif
453