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
33struct drm_clip_rect;
34struct 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 */
57struct 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 */
71struct drm_fb_helper_funcs {
72 /**
73 * @fb_dirty:
74 *
75 * Driver callback to update the framebuffer memory. If set, fbdev
76 * emulation will invoke this callback in regular intervals after
77 * the framebuffer has been written.
78 *
79 * This callback is optional.
80 *
81 * Returns:
82 * 0 on success, or an error code otherwise.
83 */
84 int (*fb_dirty)(struct drm_fb_helper *helper, struct drm_clip_rect *clip);
85
86 /**
87 * @fb_restore:
88 *
89 * Driver callback to restore internal fbdev state. If set, fbdev
90 * emulation will invoke this callback after restoring the display
91 * mode.
92 *
93 * Only for i915. Do not use in new code.
94 *
95 * TODO: Fix i915 to not require this callback.
96 */
97 void (*fb_restore)(struct drm_fb_helper *helper);
98
99 /**
100 * @fb_set_suspend:
101 *
102 * Driver callback to suspend or resume, if set, fbdev emulation will
103 * invoke this callback during suspend and resume. Driver should call
104 * fb_set_suspend() from their implementation. If not set, fbdev
105 * emulation will invoke fb_set_suspend() directly.
106 *
107 * Only for i915. Do not use in new code.
108 *
109 * TODO: Fix i915 to not require this callback.
110 */
111 void (*fb_set_suspend)(struct drm_fb_helper *helper, bool suspend);
112};
113
114/**
115 * struct drm_fb_helper - main structure to emulate fbdev on top of KMS
116 * @fb: Scanout framebuffer object
117 * @dev: DRM device
118 * @funcs: driver callbacks for fb helper
119 * @info: emulated fbdev device info struct
120 * @pseudo_palette: fake palette of 16 colors
121 * @damage_clip: clip rectangle used with deferred_io to accumulate damage to
122 * the screen buffer
123 * @damage_lock: spinlock protecting @damage_clip
124 * @damage_work: worker used to flush the framebuffer
125 * @resume_work: worker used during resume if the console lock is already taken
126 *
127 * This is the main structure used by the fbdev helpers. Drivers supporting
128 * fbdev emulation should embedded this into their overall driver structure.
129 * Drivers must also fill out a &struct drm_fb_helper_funcs with a few
130 * operations.
131 */
132struct drm_fb_helper {
133 /**
134 * @client:
135 *
136 * DRM client used by the generic fbdev emulation.
137 */
138 struct drm_client_dev client;
139
140 /**
141 * @buffer:
142 *
143 * Framebuffer used by the generic fbdev emulation.
144 */
145 struct drm_client_buffer *buffer;
146
147 struct drm_framebuffer *fb;
148 struct drm_device *dev;
149 const struct drm_fb_helper_funcs *funcs;
150 struct fb_info *info;
151 u32 pseudo_palette[17];
152 struct drm_clip_rect damage_clip;
153 spinlock_t damage_lock;
154 struct work_struct damage_work;
155 struct work_struct resume_work;
156
157 /**
158 * @lock:
159 *
160 * Top-level FBDEV helper lock. This protects all internal data
161 * structures and lists, such as @connector_info and @crtc_info.
162 *
163 * FIXME: fbdev emulation locking is a mess and long term we want to
164 * protect all helper internal state with this lock as well as reduce
165 * core KMS locking as much as possible.
166 */
167 struct mutex lock;
168
169 /**
170 * @kernel_fb_list:
171 *
172 * Entry on the global kernel_fb_helper_list, used for kgdb entry/exit.
173 */
174 struct list_head kernel_fb_list;
175
176 /**
177 * @delayed_hotplug:
178 *
179 * A hotplug was received while fbdev wasn't in control of the DRM
180 * device, i.e. another KMS master was active. The output configuration
181 * needs to be reprobe when fbdev is in control again.
182 */
183 bool delayed_hotplug;
184
185 /**
186 * @deferred_setup:
187 *
188 * If no outputs are connected (disconnected or unknown) the FB helper
189 * code will defer setup until at least one of the outputs shows up.
190 * This field keeps track of the status so that setup can be retried
191 * at every hotplug event until it succeeds eventually.
192 *
193 * Protected by @lock.
194 */
195 bool deferred_setup;
196
197 /**
198 * @preferred_bpp:
199 *
200 * Temporary storage for the driver's preferred BPP setting passed to
201 * FB helper initialization. This needs to be tracked so that deferred
202 * FB helper setup can pass this on.
203 *
204 * See also: @deferred_setup
205 */
206 int preferred_bpp;
207
208#ifdef CONFIG_FB_DEFERRED_IO
209 /**
210 * @fbdefio:
211 *
212 * Temporary storage for the driver's FB deferred I/O handler. If the
213 * driver uses the DRM fbdev emulation layer, this is set by the core
214 * to a generic deferred I/O handler if a driver is preferring to use
215 * a shadow buffer.
216 */
217 struct fb_deferred_io fbdefio;
218#endif
219};
220
221static inline struct drm_fb_helper *
222drm_fb_helper_from_client(struct drm_client_dev *client)
223{
224 return container_of(client, struct drm_fb_helper, client);
225}
226
227/**
228 * define DRM_FB_HELPER_DEFAULT_OPS - helper define for drm drivers
229 *
230 * Helper define to register default implementations of drm_fb_helper
231 * functions. To be used in struct fb_ops of drm drivers.
232 */
233#define DRM_FB_HELPER_DEFAULT_OPS \
234 .fb_check_var = drm_fb_helper_check_var, \
235 .fb_set_par = drm_fb_helper_set_par, \
236 .fb_setcmap = drm_fb_helper_setcmap, \
237 .fb_blank = drm_fb_helper_blank, \
238 .fb_pan_display = drm_fb_helper_pan_display, \
239 .fb_debug_enter = drm_fb_helper_debug_enter, \
240 .fb_debug_leave = drm_fb_helper_debug_leave, \
241 .fb_ioctl = drm_fb_helper_ioctl
242
243#ifdef CONFIG_DRM_FBDEV_EMULATION
244void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
245 unsigned int preferred_bpp,
246 const struct drm_fb_helper_funcs *funcs);
247void drm_fb_helper_unprepare(struct drm_fb_helper *fb_helper);
248int drm_fb_helper_init(struct drm_device *dev, struct drm_fb_helper *helper);
249void drm_fb_helper_fini(struct drm_fb_helper *helper);
250int drm_fb_helper_blank(int blank, struct fb_info *info);
251int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
252 struct fb_info *info);
253int drm_fb_helper_set_par(struct fb_info *info);
254int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
255 struct fb_info *info);
256
257int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper,
258 bool force);
259
260void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper);
261void drm_fb_helper_fill_info(struct fb_info *info,
262 struct drm_fb_helper *fb_helper,
263 struct drm_fb_helper_surface_size *sizes);
264
265void drm_fb_helper_damage_range(struct fb_info *info, off_t off, size_t len);
266void drm_fb_helper_damage_area(struct fb_info *info, u32 x, u32 y, u32 width, u32 height);
267
268#ifdef CONFIG_FB_DEFERRED_IO
269void drm_fb_helper_deferred_io(struct fb_info *info, struct list_head *pagereflist);
270#endif
271
272void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend);
273void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
274 bool suspend);
275
276int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info);
277
278int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
279 unsigned long arg);
280
281int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper);
282int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper);
283int drm_fb_helper_debug_enter(struct fb_info *info);
284int drm_fb_helper_debug_leave(struct fb_info *info);
285#else
286static inline void drm_fb_helper_prepare(struct drm_device *dev,
287 struct drm_fb_helper *helper,
288 unsigned int preferred_bpp,
289 const struct drm_fb_helper_funcs *funcs)
290{
291}
292
293static inline void drm_fb_helper_unprepare(struct drm_fb_helper *fb_helper)
294{
295}
296
297static inline int drm_fb_helper_init(struct drm_device *dev,
298 struct drm_fb_helper *helper)
299{
300 /* So drivers can use it to free the struct */
301 helper->dev = dev;
302 dev->fb_helper = helper;
303
304 return 0;
305}
306
307static inline void drm_fb_helper_fini(struct drm_fb_helper *helper)
308{
309 if (helper && helper->dev)
310 helper->dev->fb_helper = NULL;
311}
312
313static inline int drm_fb_helper_blank(int blank, struct fb_info *info)
314{
315 return 0;
316}
317
318static inline int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
319 struct fb_info *info)
320{
321 return 0;
322}
323
324static inline int drm_fb_helper_set_par(struct fb_info *info)
325{
326 return 0;
327}
328
329static inline int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
330 struct fb_info *info)
331{
332 return 0;
333}
334
335static inline int
336drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
337{
338 return 0;
339}
340
341static inline void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper)
342{
343}
344
345static inline void
346drm_fb_helper_fill_info(struct fb_info *info,
347 struct drm_fb_helper *fb_helper,
348 struct drm_fb_helper_surface_size *sizes)
349{
350}
351
352static inline int drm_fb_helper_setcmap(struct fb_cmap *cmap,
353 struct fb_info *info)
354{
355 return 0;
356}
357
358static inline int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
359 unsigned long arg)
360{
361 return 0;
362}
363
364#ifdef CONFIG_FB_DEFERRED_IO
365static inline void drm_fb_helper_deferred_io(struct fb_info *info,
366 struct list_head *pagelist)
367{
368}
369#endif
370
371static inline void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper,
372 bool suspend)
373{
374}
375
376static inline void
377drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper, bool suspend)
378{
379}
380
381static inline int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
382{
383 return 0;
384}
385
386static inline int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper)
387{
388 return 0;
389}
390
391static inline int drm_fb_helper_debug_enter(struct fb_info *info)
392{
393 return 0;
394}
395
396static inline int drm_fb_helper_debug_leave(struct fb_info *info)
397{
398 return 0;
399}
400#endif
401
402#endif
403

source code of linux/include/drm/drm_fb_helper.h