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