include/drm/drm_fb_helper.h

   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_crtc.h>
  36 #include <linux/kgdb.h>
  37
  38 enum mode_set_atomic {
  39         LEAVE_ATOMIC_MODE_SET,
  40         ENTER_ATOMIC_MODE_SET,
  41 };
  42
  43 struct drm_fb_offset {
  44         int x, y;
  45 };
  46
  47 struct drm_fb_helper_crtc {
  48         struct drm_mode_set mode_set;
  49         struct drm_display_mode *desired_mode;
  50         int x, y;
  51 };
  52
  53 /**
  54  * struct drm_fb_helper_surface_size - describes fbdev size and scanout surface size
  55  * @fb_width: fbdev width
  56  * @fb_height: fbdev height
  57  * @surface_width: scanout buffer width
  58  * @surface_height: scanout buffer height
  59  * @surface_bpp: scanout buffer bpp
  60  * @surface_depth: scanout buffer depth
  61  *
  62  * Note that the scanout surface width/height may be larger than the fbdev
  63  * width/height.  In case of multiple displays, the scanout surface is sized
  64  * according to the largest width/height (so it is large enough for all CRTCs
  65  * to scanout).  But the fbdev width/height is sized to the minimum width/
  66  * height of all the displays.  This ensures that fbcon fits on the smallest
  67  * of the attached displays.
  68  *
  69  * So what is passed to drm_fb_helper_fill_var() should be fb_width/fb_height,
  70  * rather than the surface size.
  71  */
  72 struct drm_fb_helper_surface_size {
  73         u32 fb_width;
  74         u32 fb_height;
  75         u32 surface_width;
  76         u32 surface_height;
  77         u32 surface_bpp;
  78         u32 surface_depth;
  79 };
  80
  81 /**
  82  * struct drm_fb_helper_funcs - driver callbacks for the fbdev emulation library
  83  *
  84  * Driver callbacks used by the fbdev emulation helper library.
  85  */
  86 struct drm_fb_helper_funcs {
  87         /**
  88          * @gamma_set:
  89          *
  90          * Set the given gamma LUT register on the given CRTC.
  91          *
  92          * This callback is optional.
  93          *
  94          * FIXME:
  95          *
  96          * This callback is functionally redundant with the core gamma table
  97          * support and simply exists because the fbdev hasn't yet been
  98          * refactored to use the core gamma table interfaces.
  99          */
 100         void (*gamma_set)(struct drm_crtc *crtc, u16 red, u16 green,
 101                           u16 blue, int regno);
 102         /**
 103          * @gamma_get:
 104          *
 105          * Read the given gamma LUT register on the given CRTC, used to save the
 106          * current LUT when force-restoring the fbdev for e.g. kdbg.
 107          *
 108          * This callback is optional.
 109          *
 110          * FIXME:
 111          *
 112          * This callback is functionally redundant with the core gamma table
 113          * support and simply exists because the fbdev hasn't yet been
 114          * refactored to use the core gamma table interfaces.
 115          */
 116         void (*gamma_get)(struct drm_crtc *crtc, u16 *red, u16 *green,
 117                           u16 *blue, int regno);
 118
 119         /**
 120          * @fb_probe:
 121          *
 122          * Driver callback to allocate and initialize the fbdev info structure.
 123          * Furthermore it also needs to allocate the DRM framebuffer used to
 124          * back the fbdev.
 125          *
 126          * This callback is mandatory.
 127          *
 128          * RETURNS:
 129          *
 130          * The driver should return 0 on success and a negative error code on
 131          * failure.
 132          */
 133         int (*fb_probe)(struct drm_fb_helper *helper,
 134                         struct drm_fb_helper_surface_size *sizes);
 135
 136         /**
 137          * @initial_config:
 138          *
 139          * Driver callback to setup an initial fbdev display configuration.
 140          * Drivers can use this callback to tell the fbdev emulation what the
 141          * preferred initial configuration is. This is useful to implement
 142          * smooth booting where the fbdev (and subsequently all userspace) never
 143          * changes the mode, but always inherits the existing configuration.
 144          *
 145          * This callback is optional.
 146          *
 147          * RETURNS:
 148          *
 149          * The driver should return true if a suitable initial configuration has
 150          * been filled out and false when the fbdev helper should fall back to
 151          * the default probing logic.
 152          */
 153         bool (*initial_config)(struct drm_fb_helper *fb_helper,
 154                                struct drm_fb_helper_crtc **crtcs,
 155                                struct drm_display_mode **modes,
 156                                struct drm_fb_offset *offsets,
 157                                bool *enabled, int width, int height);
 158 };
 159
 160 struct drm_fb_helper_connector {
 161         struct drm_connector *connector;
 162 };
 163
 164 /**
 165  * struct drm_fb_helper - main structure to emulate fbdev on top of KMS
 166  * @fb: Scanout framebuffer object
 167  * @dev: DRM device
 168  * @crtc_count: number of possible CRTCs
 169  * @crtc_info: per-CRTC helper state (mode, x/y offset, etc)
 170  * @connector_count: number of connected connectors
 171  * @connector_info_alloc_count: size of connector_info
 172  * @connector_info: array of per-connector information
 173  * @funcs: driver callbacks for fb helper
 174  * @fbdev: emulated fbdev device info struct
 175  * @pseudo_palette: fake palette of 16 colors
 176  * @dirty_clip: clip rectangle used with deferred_io to accumulate damage to
 177  *              the screen buffer
 178  * @dirty_lock: spinlock protecting @dirty_clip
 179  * @dirty_work: worker used to flush the framebuffer
 180  * @resume_work: worker used during resume if the console lock is already taken
 181  *
 182  * This is the main structure used by the fbdev helpers. Drivers supporting
 183  * fbdev emulation should embedded this into their overall driver structure.
 184  * Drivers must also fill out a &struct drm_fb_helper_funcs with a few
 185  * operations.
 186  */
 187 struct drm_fb_helper {
 188         struct drm_framebuffer *fb;
 189         struct drm_device *dev;
 190         int crtc_count;
 191         struct drm_fb_helper_crtc *crtc_info;
 192         int connector_count;
 193         int connector_info_alloc_count;
 194         struct drm_fb_helper_connector **connector_info;
 195         const struct drm_fb_helper_funcs *funcs;
 196         struct fb_info *fbdev;
 197         u32 pseudo_palette[17];
 198         struct drm_clip_rect dirty_clip;
 199         spinlock_t dirty_lock;
 200         struct work_struct dirty_work;
 201         struct work_struct resume_work;
 202
 203         /**
 204          * @kernel_fb_list:
 205          *
 206          * Entry on the global kernel_fb_helper_list, used for kgdb entry/exit.
 207          */
 208         struct list_head kernel_fb_list;
 209
 210         /**
 211          * @delayed_hotplug:
 212          *
 213          * A hotplug was received while fbdev wasn't in control of the DRM
 214          * device, i.e. another KMS master was active. The output configuration
 215          * needs to be reprobe when fbdev is in control again.
 216          */
 217         bool delayed_hotplug;
 218 };
 219
 220 /**
 221  * define DRM_FB_HELPER_DEFAULT_OPS - helper define for drm drivers
 222  *
 223  * Helper define to register default implementations of drm_fb_helper
 224  * functions. To be used in struct fb_ops of drm drivers.
 225  */
 226 #define DRM_FB_HELPER_DEFAULT_OPS \
 227         .fb_check_var   = drm_fb_helper_check_var, \
 228         .fb_set_par     = drm_fb_helper_set_par, \
 229         .fb_setcmap     = drm_fb_helper_setcmap, \
 230         .fb_blank       = drm_fb_helper_blank, \
 231         .fb_pan_display = drm_fb_helper_pan_display, \
 232         .fb_debug_enter = drm_fb_helper_debug_enter, \
 233         .fb_debug_leave = drm_fb_helper_debug_leave
 234
 235 #ifdef CONFIG_DRM_FBDEV_EMULATION
 236 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
 237                            const struct drm_fb_helper_funcs *funcs);
 238 int drm_fb_helper_init(struct drm_device *dev,
 239                        struct drm_fb_helper *helper, int max_conn);
 240 void drm_fb_helper_fini(struct drm_fb_helper *helper);
 241 int drm_fb_helper_blank(int blank, struct fb_info *info);
 242 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
 243                               struct fb_info *info);
 244 int drm_fb_helper_set_par(struct fb_info *info);
 245 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
 246                             struct fb_info *info);
 247
 248 int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper);
 249
 250 struct fb_info *drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper);
 251 void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper);
 252 void drm_fb_helper_release_fbi(struct drm_fb_helper *fb_helper);
 253 void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
 254                             uint32_t fb_width, uint32_t fb_height);
 255 void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
 256                             uint32_t depth);
 257
 258 void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper);
 259
 260 void drm_fb_helper_deferred_io(struct fb_info *info,
 261                                struct list_head *pagelist);
 262
 263 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
 264                                size_t count, loff_t *ppos);
 265 ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
 266                                 size_t count, loff_t *ppos);
 267
 268 void drm_fb_helper_sys_fillrect(struct fb_info *info,
 269                                 const struct fb_fillrect *rect);
 270 void drm_fb_helper_sys_copyarea(struct fb_info *info,
 271                                 const struct fb_copyarea *area);
 272 void drm_fb_helper_sys_imageblit(struct fb_info *info,
 273                                  const struct fb_image *image);
 274
 275 void drm_fb_helper_cfb_fillrect(struct fb_info *info,
 276                                 const struct fb_fillrect *rect);
 277 void drm_fb_helper_cfb_copyarea(struct fb_info *info,
 278                                 const struct fb_copyarea *area);
 279 void drm_fb_helper_cfb_imageblit(struct fb_info *info,
 280                                  const struct fb_image *image);
 281
 282 void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend);
 283 void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
 284                                         bool suspend);
 285
 286 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info);
 287
 288 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper);
 289 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel);
 290 int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper);
 291 int drm_fb_helper_debug_enter(struct fb_info *info);
 292 int drm_fb_helper_debug_leave(struct fb_info *info);
 293 struct drm_display_mode *
 294 drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector,
 295                         int width, int height);
 296 struct drm_display_mode *
 297 drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn);
 298
 299 int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper, struct drm_connector *connector);
 300 int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 301                                        struct drm_connector *connector);
 302 #else
 303 static inline void drm_fb_helper_prepare(struct drm_device *dev,
 304                                         struct drm_fb_helper *helper,
 305                                         const struct drm_fb_helper_funcs *funcs)
 306 {
 307 }
 308
 309 static inline int drm_fb_helper_init(struct drm_device *dev,
 310                        struct drm_fb_helper *helper,
 311                        int max_conn)
 312 {
 313         return 0;
 314 }
 315
 316 static inline void drm_fb_helper_fini(struct drm_fb_helper *helper)
 317 {
 318 }
 319
 320 static inline int drm_fb_helper_blank(int blank, struct fb_info *info)
 321 {
 322         return 0;
 323 }
 324
 325 static inline int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
 326                                             struct fb_info *info)
 327 {
 328         return 0;
 329 }
 330
 331 static inline int drm_fb_helper_set_par(struct fb_info *info)
 332 {
 333         return 0;
 334 }
 335
 336 static inline int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
 337                                           struct fb_info *info)
 338 {
 339         return 0;
 340 }
 341
 342 static inline int
 343 drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
 344 {
 345         return 0;
 346 }
 347
 348 static inline struct fb_info *
 349 drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper)
 350 {
 351         return NULL;
 352 }
 353
 354 static inline void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper)
 355 {
 356 }
 357 static inline void drm_fb_helper_release_fbi(struct drm_fb_helper *fb_helper)
 358 {
 359 }
 360
 361 static inline void drm_fb_helper_fill_var(struct fb_info *info,
 362                                           struct drm_fb_helper *fb_helper,
 363                                           uint32_t fb_width, uint32_t fb_height)
 364 {
 365 }
 366
 367 static inline void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
 368                                           uint32_t depth)
 369 {
 370 }
 371
 372 static inline int drm_fb_helper_setcmap(struct fb_cmap *cmap,
 373                                         struct fb_info *info)
 374 {
 375         return 0;
 376 }
 377
 378 static inline void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper)
 379 {
 380 }
 381
 382 static inline void drm_fb_helper_deferred_io(struct fb_info *info,
 383                                              struct list_head *pagelist)
 384 {
 385 }
 386
 387 static inline ssize_t drm_fb_helper_sys_read(struct fb_info *info,
 388                                              char __user *buf, size_t count,
 389                                              loff_t *ppos)
 390 {
 391         return -ENODEV;
 392 }
 393
 394 static inline ssize_t drm_fb_helper_sys_write(struct fb_info *info,
 395                                               const char __user *buf,
 396                                               size_t count, loff_t *ppos)
 397 {
 398         return -ENODEV;
 399 }
 400
 401 static inline void drm_fb_helper_sys_fillrect(struct fb_info *info,
 402                                               const struct fb_fillrect *rect)
 403 {
 404 }
 405
 406 static inline void drm_fb_helper_sys_copyarea(struct fb_info *info,
 407                                               const struct fb_copyarea *area)
 408 {
 409 }
 410
 411 static inline void drm_fb_helper_sys_imageblit(struct fb_info *info,
 412                                                const struct fb_image *image)
 413 {
 414 }
 415
 416 static inline void drm_fb_helper_cfb_fillrect(struct fb_info *info,
 417                                               const struct fb_fillrect *rect)
 418 {
 419 }
 420
 421 static inline void drm_fb_helper_cfb_copyarea(struct fb_info *info,
 422                                               const struct fb_copyarea *area)
 423 {
 424 }
 425
 426 static inline void drm_fb_helper_cfb_imageblit(struct fb_info *info,
 427                                                const struct fb_image *image)
 428 {
 429 }
 430
 431 static inline void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper,
 432                                              bool suspend)
 433 {
 434 }
 435
 436 static inline void
 437 drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper, bool suspend)
 438 {
 439 }
 440
 441 static inline int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
 442 {
 443         return 0;
 444 }
 445
 446 static inline int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper,
 447                                                int bpp_sel)
 448 {
 449         return 0;
 450 }
 451
 452 static inline int
 453 drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
 454 {
 455         return 0;
 456 }
 457
 458 static inline int drm_fb_helper_debug_enter(struct fb_info *info)
 459 {
 460         return 0;
 461 }
 462
 463 static inline int drm_fb_helper_debug_leave(struct fb_info *info)
 464 {
 465         return 0;
 466 }
 467
 468 static inline struct drm_display_mode *
 469 drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector,
 470                        int width, int height)
 471 {
 472         return NULL;
 473 }
 474
 475 static inline struct drm_display_mode *
 476 drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
 477                       int width, int height)
 478 {
 479         return NULL;
 480 }
 481
 482 static inline int
 483 drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper,
 484                                 struct drm_connector *connector)
 485 {
 486         return 0;
 487 }
 488
 489 static inline int
 490 drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 491                                    struct drm_connector *connector)
 492 {
 493         return 0;
 494 }
 495
 496 #endif
 497
 498 static inline int
 499 drm_fb_helper_remove_conflicting_framebuffers(struct apertures_struct *a,
 500                                               const char *name, bool primary)
 501 {
 502 #if IS_REACHABLE(CONFIG_FB)
 503         return remove_conflicting_framebuffers(a, name, primary);
 504 #else
 505         return 0;
 506 #endif
 507 }
 508
 509 #endif