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          * @fb_probe:
  89          *
  90          * Driver callback to allocate and initialize the fbdev info structure.
  91          * Furthermore it also needs to allocate the DRM framebuffer used to
  92          * back the fbdev.
  93          *
  94          * This callback is mandatory.
  95          *
  96          * RETURNS:
  97          *
  98          * The driver should return 0 on success and a negative error code on
  99          * failure.
 100          */
 101         int (*fb_probe)(struct drm_fb_helper *helper,
 102                         struct drm_fb_helper_surface_size *sizes);
 103
 104         /**
 105          * @initial_config:
 106          *
 107          * Driver callback to setup an initial fbdev display configuration.
 108          * Drivers can use this callback to tell the fbdev emulation what the
 109          * preferred initial configuration is. This is useful to implement
 110          * smooth booting where the fbdev (and subsequently all userspace) never
 111          * changes the mode, but always inherits the existing configuration.
 112          *
 113          * This callback is optional.
 114          *
 115          * RETURNS:
 116          *
 117          * The driver should return true if a suitable initial configuration has
 118          * been filled out and false when the fbdev helper should fall back to
 119          * the default probing logic.
 120          */
 121         bool (*initial_config)(struct drm_fb_helper *fb_helper,
 122                                struct drm_fb_helper_crtc **crtcs,
 123                                struct drm_display_mode **modes,
 124                                struct drm_fb_offset *offsets,
 125                                bool *enabled, int width, int height);
 126 };
 127
 128 struct drm_fb_helper_connector {
 129         struct drm_connector *connector;
 130 };
 131
 132 /**
 133  * struct drm_fb_helper - main structure to emulate fbdev on top of KMS
 134  * @fb: Scanout framebuffer object
 135  * @dev: DRM device
 136  * @crtc_count: number of possible CRTCs
 137  * @crtc_info: per-CRTC helper state (mode, x/y offset, etc)
 138  * @connector_count: number of connected connectors
 139  * @connector_info_alloc_count: size of connector_info
 140  * @funcs: driver callbacks for fb helper
 141  * @fbdev: emulated fbdev device info struct
 142  * @pseudo_palette: fake palette of 16 colors
 143  * @dirty_clip: clip rectangle used with deferred_io to accumulate damage to
 144  *              the screen buffer
 145  * @dirty_lock: spinlock protecting @dirty_clip
 146  * @dirty_work: worker used to flush the framebuffer
 147  * @resume_work: worker used during resume if the console lock is already taken
 148  *
 149  * This is the main structure used by the fbdev helpers. Drivers supporting
 150  * fbdev emulation should embedded this into their overall driver structure.
 151  * Drivers must also fill out a &struct drm_fb_helper_funcs with a few
 152  * operations.
 153  */
 154 struct drm_fb_helper {
 155         struct drm_framebuffer *fb;
 156         struct drm_device *dev;
 157         int crtc_count;
 158         struct drm_fb_helper_crtc *crtc_info;
 159         int connector_count;
 160         int connector_info_alloc_count;
 161         /**
 162          * @connector_info:
 163          *
 164          * Array of per-connector information. Do not iterate directly, but use
 165          * drm_fb_helper_for_each_connector.
 166          */
 167         struct drm_fb_helper_connector **connector_info;
 168         const struct drm_fb_helper_funcs *funcs;
 169         struct fb_info *fbdev;
 170         u32 pseudo_palette[17];
 171         struct drm_clip_rect dirty_clip;
 172         spinlock_t dirty_lock;
 173         struct work_struct dirty_work;
 174         struct work_struct resume_work;
 175
 176         /**
 177          * @lock:
 178          *
 179          * Top-level FBDEV helper lock. This protects all internal data
 180          * structures and lists, such as @connector_info and @crtc_info.
 181          *
 182          * FIXME: fbdev emulation locking is a mess and long term we want to
 183          * protect all helper internal state with this lock as well as reduce
 184          * core KMS locking as much as possible.
 185          */
 186         struct mutex lock;
 187
 188         /**
 189          * @kernel_fb_list:
 190          *
 191          * Entry on the global kernel_fb_helper_list, used for kgdb entry/exit.
 192          */
 193         struct list_head kernel_fb_list;
 194
 195         /**
 196          * @delayed_hotplug:
 197          *
 198          * A hotplug was received while fbdev wasn't in control of the DRM
 199          * device, i.e. another KMS master was active. The output configuration
 200          * needs to be reprobe when fbdev is in control again.
 201          */
 202         bool delayed_hotplug;
 203
 204         /**
 205          * @deferred_setup:
 206          *
 207          * If no outputs are connected (disconnected or unknown) the FB helper
 208          * code will defer setup until at least one of the outputs shows up.
 209          * This field keeps track of the status so that setup can be retried
 210          * at every hotplug event until it succeeds eventually.
 211          *
 212          * Protected by @lock.
 213          */
 214         bool deferred_setup;
 215
 216         /**
 217          * @preferred_bpp:
 218          *
 219          * Temporary storage for the driver's preferred BPP setting passed to
 220          * FB helper initialization. This needs to be tracked so that deferred
 221          * FB helper setup can pass this on.
 222          *
 223          * See also: @deferred_setup
 224          */
 225         int preferred_bpp;
 226 };
 227
 228 /**
 229  * define DRM_FB_HELPER_DEFAULT_OPS - helper define for drm drivers
 230  *
 231  * Helper define to register default implementations of drm_fb_helper
 232  * functions. To be used in struct fb_ops of drm drivers.
 233  */
 234 #define DRM_FB_HELPER_DEFAULT_OPS \
 235         .fb_check_var   = drm_fb_helper_check_var, \
 236         .fb_set_par     = drm_fb_helper_set_par, \
 237         .fb_setcmap     = drm_fb_helper_setcmap, \
 238         .fb_blank       = drm_fb_helper_blank, \
 239         .fb_pan_display = drm_fb_helper_pan_display, \
 240         .fb_debug_enter = drm_fb_helper_debug_enter, \
 241         .fb_debug_leave = drm_fb_helper_debug_leave, \
 242         .fb_ioctl       = drm_fb_helper_ioctl
 243
 244 #ifdef CONFIG_DRM_FBDEV_EMULATION
 245 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
 246                            const struct drm_fb_helper_funcs *funcs);
 247 int drm_fb_helper_init(struct drm_device *dev,
 248                        struct drm_fb_helper *helper, int max_conn);
 249 void drm_fb_helper_fini(struct drm_fb_helper *helper);
 250 int drm_fb_helper_blank(int blank, struct fb_info *info);
 251 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
 252                               struct fb_info *info);
 253 int drm_fb_helper_set_par(struct fb_info *info);
 254 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
 255                             struct fb_info *info);
 256
 257 int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper);
 258
 259 struct fb_info *drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper);
 260 void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper);
 261 void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
 262                             uint32_t fb_width, uint32_t fb_height);
 263 void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
 264                             uint32_t depth);
 265
 266 void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper);
 267
 268 void drm_fb_helper_deferred_io(struct fb_info *info,
 269                                struct list_head *pagelist);
 270
 271 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
 272                                size_t count, loff_t *ppos);
 273 ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
 274                                 size_t count, loff_t *ppos);
 275
 276 void drm_fb_helper_sys_fillrect(struct fb_info *info,
 277                                 const struct fb_fillrect *rect);
 278 void drm_fb_helper_sys_copyarea(struct fb_info *info,
 279                                 const struct fb_copyarea *area);
 280 void drm_fb_helper_sys_imageblit(struct fb_info *info,
 281                                  const struct fb_image *image);
 282
 283 void drm_fb_helper_cfb_fillrect(struct fb_info *info,
 284                                 const struct fb_fillrect *rect);
 285 void drm_fb_helper_cfb_copyarea(struct fb_info *info,
 286                                 const struct fb_copyarea *area);
 287 void drm_fb_helper_cfb_imageblit(struct fb_info *info,
 288                                  const struct fb_image *image);
 289
 290 void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend);
 291 void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
 292                                         bool suspend);
 293
 294 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info);
 295
 296 int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
 297                         unsigned long arg);
 298
 299 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper);
 300 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel);
 301 int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper);
 302 int drm_fb_helper_debug_enter(struct fb_info *info);
 303 int drm_fb_helper_debug_leave(struct fb_info *info);
 304 struct drm_display_mode *
 305 drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector,
 306                         int width, int height);
 307 struct drm_display_mode *
 308 drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn);
 309
 310 int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper, struct drm_connector *connector);
 311 int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 312                                        struct drm_connector *connector);
 313 #else
 314 static inline void drm_fb_helper_prepare(struct drm_device *dev,
 315                                         struct drm_fb_helper *helper,
 316                                         const struct drm_fb_helper_funcs *funcs)
 317 {
 318 }
 319
 320 static inline int drm_fb_helper_init(struct drm_device *dev,
 321                        struct drm_fb_helper *helper,
 322                        int max_conn)
 323 {
 324         return 0;
 325 }
 326
 327 static inline void drm_fb_helper_fini(struct drm_fb_helper *helper)
 328 {
 329 }
 330
 331 static inline int drm_fb_helper_blank(int blank, struct fb_info *info)
 332 {
 333         return 0;
 334 }
 335
 336 static inline int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
 337                                             struct fb_info *info)
 338 {
 339         return 0;
 340 }
 341
 342 static inline int drm_fb_helper_set_par(struct fb_info *info)
 343 {
 344         return 0;
 345 }
 346
 347 static inline int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
 348                                           struct fb_info *info)
 349 {
 350         return 0;
 351 }
 352
 353 static inline int
 354 drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
 355 {
 356         return 0;
 357 }
 358
 359 static inline struct fb_info *
 360 drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper)
 361 {
 362         return NULL;
 363 }
 364
 365 static inline void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper)
 366 {
 367 }
 368
 369 static inline void drm_fb_helper_fill_var(struct fb_info *info,
 370                                           struct drm_fb_helper *fb_helper,
 371                                           uint32_t fb_width, uint32_t fb_height)
 372 {
 373 }
 374
 375 static inline void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
 376                                           uint32_t depth)
 377 {
 378 }
 379
 380 static inline int drm_fb_helper_setcmap(struct fb_cmap *cmap,
 381                                         struct fb_info *info)
 382 {
 383         return 0;
 384 }
 385
 386 static inline int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
 387                                       unsigned long arg)
 388 {
 389         return 0;
 390 }
 391
 392 static inline void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper)
 393 {
 394 }
 395
 396 static inline void drm_fb_helper_deferred_io(struct fb_info *info,
 397                                              struct list_head *pagelist)
 398 {
 399 }
 400
 401 static inline ssize_t drm_fb_helper_sys_read(struct fb_info *info,
 402                                              char __user *buf, size_t count,
 403                                              loff_t *ppos)
 404 {
 405         return -ENODEV;
 406 }
 407
 408 static inline ssize_t drm_fb_helper_sys_write(struct fb_info *info,
 409                                               const char __user *buf,
 410                                               size_t count, loff_t *ppos)
 411 {
 412         return -ENODEV;
 413 }
 414
 415 static inline void drm_fb_helper_sys_fillrect(struct fb_info *info,
 416                                               const struct fb_fillrect *rect)
 417 {
 418 }
 419
 420 static inline void drm_fb_helper_sys_copyarea(struct fb_info *info,
 421                                               const struct fb_copyarea *area)
 422 {
 423 }
 424
 425 static inline void drm_fb_helper_sys_imageblit(struct fb_info *info,
 426                                                const struct fb_image *image)
 427 {
 428 }
 429
 430 static inline void drm_fb_helper_cfb_fillrect(struct fb_info *info,
 431                                               const struct fb_fillrect *rect)
 432 {
 433 }
 434
 435 static inline void drm_fb_helper_cfb_copyarea(struct fb_info *info,
 436                                               const struct fb_copyarea *area)
 437 {
 438 }
 439
 440 static inline void drm_fb_helper_cfb_imageblit(struct fb_info *info,
 441                                                const struct fb_image *image)
 442 {
 443 }
 444
 445 static inline void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper,
 446                                              bool suspend)
 447 {
 448 }
 449
 450 static inline void
 451 drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper, bool suspend)
 452 {
 453 }
 454
 455 static inline int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
 456 {
 457         return 0;
 458 }
 459
 460 static inline int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper,
 461                                                int bpp_sel)
 462 {
 463         return 0;
 464 }
 465
 466 static inline int
 467 drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
 468 {
 469         return 0;
 470 }
 471
 472 static inline int drm_fb_helper_debug_enter(struct fb_info *info)
 473 {
 474         return 0;
 475 }
 476
 477 static inline int drm_fb_helper_debug_leave(struct fb_info *info)
 478 {
 479         return 0;
 480 }
 481
 482 static inline struct drm_display_mode *
 483 drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector,
 484                        int width, int height)
 485 {
 486         return NULL;
 487 }
 488
 489 static inline struct drm_display_mode *
 490 drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
 491                       int width, int height)
 492 {
 493         return NULL;
 494 }
 495
 496 static inline int
 497 drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper,
 498                                 struct drm_connector *connector)
 499 {
 500         return 0;
 501 }
 502
 503 static inline int
 504 drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 505                                    struct drm_connector *connector)
 506 {
 507         return 0;
 508 }
 509
 510 #endif
 511
 512 static inline int
 513 drm_fb_helper_remove_conflicting_framebuffers(struct apertures_struct *a,
 514                                               const char *name, bool primary)
 515 {
 516 #if IS_REACHABLE(CONFIG_FB)
 517         return remove_conflicting_framebuffers(a, name, primary);
 518 #else
 519         return 0;
 520 #endif
 521 }
 522
 523 #endif