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_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 */
122struct 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#ifdef CONFIG_FB_DEFERRED_IO
199 /**
200 * @fbdefio:
201 *
202 * Temporary storage for the driver's FB deferred I/O handler. If the
203 * driver uses the DRM fbdev emulation layer, this is set by the core
204 * to a generic deferred I/O handler if a driver is preferring to use
205 * a shadow buffer.
206 */
207 struct fb_deferred_io fbdefio;
208#endif
209};
210
211static inline struct drm_fb_helper *
212drm_fb_helper_from_client(struct drm_client_dev *client)
213{
214 return container_of(client, struct drm_fb_helper, client);
215}
216
217/**
218 * define DRM_FB_HELPER_DEFAULT_OPS - helper define for drm drivers
219 *
220 * Helper define to register default implementations of drm_fb_helper
221 * functions. To be used in struct fb_ops of drm drivers.
222 */
223#define DRM_FB_HELPER_DEFAULT_OPS \
224 .fb_check_var = drm_fb_helper_check_var, \
225 .fb_set_par = drm_fb_helper_set_par, \
226 .fb_setcmap = drm_fb_helper_setcmap, \
227 .fb_blank = drm_fb_helper_blank, \
228 .fb_pan_display = drm_fb_helper_pan_display, \
229 .fb_debug_enter = drm_fb_helper_debug_enter, \
230 .fb_debug_leave = drm_fb_helper_debug_leave, \
231 .fb_ioctl = drm_fb_helper_ioctl
232
233#ifdef CONFIG_DRM_FBDEV_EMULATION
234void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
235 unsigned int preferred_bpp,
236 const struct drm_fb_helper_funcs *funcs);
237void drm_fb_helper_unprepare(struct drm_fb_helper *fb_helper);
238int drm_fb_helper_init(struct drm_device *dev, struct drm_fb_helper *helper);
239void drm_fb_helper_fini(struct drm_fb_helper *helper);
240int drm_fb_helper_blank(int blank, struct fb_info *info);
241int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
242 struct fb_info *info);
243int drm_fb_helper_set_par(struct fb_info *info);
244int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
245 struct fb_info *info);
246
247int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper);
248
249struct fb_info *drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper);
250void drm_fb_helper_release_info(struct drm_fb_helper *fb_helper);
251void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper);
252void drm_fb_helper_fill_info(struct fb_info *info,
253 struct drm_fb_helper *fb_helper,
254 struct drm_fb_helper_surface_size *sizes);
255
256void drm_fb_helper_damage_range(struct fb_info *info, off_t off, size_t len);
257void drm_fb_helper_damage_area(struct fb_info *info, u32 x, u32 y, u32 width, u32 height);
258
259void drm_fb_helper_deferred_io(struct fb_info *info, struct list_head *pagereflist);
260
261void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend);
262void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
263 bool suspend);
264
265int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info);
266
267int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
268 unsigned long arg);
269
270int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper);
271int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper);
272int drm_fb_helper_debug_enter(struct fb_info *info);
273int drm_fb_helper_debug_leave(struct fb_info *info);
274
275void drm_fb_helper_lastclose(struct drm_device *dev);
276void drm_fb_helper_output_poll_changed(struct drm_device *dev);
277#else
278static inline void drm_fb_helper_prepare(struct drm_device *dev,
279 struct drm_fb_helper *helper,
280 unsigned int preferred_bpp,
281 const struct drm_fb_helper_funcs *funcs)
282{
283}
284
285static inline void drm_fb_helper_unprepare(struct drm_fb_helper *fb_helper)
286{
287}
288
289static inline int drm_fb_helper_init(struct drm_device *dev,
290 struct drm_fb_helper *helper)
291{
292 /* So drivers can use it to free the struct */
293 helper->dev = dev;
294 dev->fb_helper = helper;
295
296 return 0;
297}
298
299static inline void drm_fb_helper_fini(struct drm_fb_helper *helper)
300{
301 if (helper && helper->dev)
302 helper->dev->fb_helper = NULL;
303}
304
305static inline int drm_fb_helper_blank(int blank, struct fb_info *info)
306{
307 return 0;
308}
309
310static inline int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
311 struct fb_info *info)
312{
313 return 0;
314}
315
316static inline int drm_fb_helper_set_par(struct fb_info *info)
317{
318 return 0;
319}
320
321static inline int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
322 struct fb_info *info)
323{
324 return 0;
325}
326
327static inline int
328drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
329{
330 return 0;
331}
332
333static inline struct fb_info *
334drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper)
335{
336 return NULL;
337}
338
339static inline void drm_fb_helper_release_info(struct drm_fb_helper *fb_helper)
340{
341}
342
343static inline void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper)
344{
345}
346
347static inline void
348drm_fb_helper_fill_info(struct fb_info *info,
349 struct drm_fb_helper *fb_helper,
350 struct drm_fb_helper_surface_size *sizes)
351{
352}
353
354static inline int drm_fb_helper_setcmap(struct fb_cmap *cmap,
355 struct fb_info *info)
356{
357 return 0;
358}
359
360static inline int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
361 unsigned long arg)
362{
363 return 0;
364}
365
366static inline void drm_fb_helper_deferred_io(struct fb_info *info,
367 struct list_head *pagelist)
368{
369}
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
401static inline void drm_fb_helper_lastclose(struct drm_device *dev)
402{
403}
404
405static inline void drm_fb_helper_output_poll_changed(struct drm_device *dev)
406{
407}
408#endif
409
410#endif
411

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