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 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
 223                            const struct drm_fb_helper_funcs *funcs);
 224 int drm_fb_helper_init(struct drm_device *dev,
 225                        struct drm_fb_helper *helper, int crtc_count,
 226                        int max_conn);
 227 void drm_fb_helper_fini(struct drm_fb_helper *helper);
 228 int drm_fb_helper_blank(int blank, struct fb_info *info);
 229 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
 230                               struct fb_info *info);
 231 int drm_fb_helper_set_par(struct fb_info *info);
 232 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
 233                             struct fb_info *info);
 234
 235 int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper);
 236
 237 struct fb_info *drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper);
 238 void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper);
 239 void drm_fb_helper_release_fbi(struct drm_fb_helper *fb_helper);
 240 void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
 241                             uint32_t fb_width, uint32_t fb_height);
 242 void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
 243                             uint32_t depth);
 244
 245 void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper);
 246
 247 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
 248                                size_t count, loff_t *ppos);
 249 ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
 250                                 size_t count, loff_t *ppos);
 251
 252 void drm_fb_helper_sys_fillrect(struct fb_info *info,
 253                                 const struct fb_fillrect *rect);
 254 void drm_fb_helper_sys_copyarea(struct fb_info *info,
 255                                 const struct fb_copyarea *area);
 256 void drm_fb_helper_sys_imageblit(struct fb_info *info,
 257                                  const struct fb_image *image);
 258
 259 void drm_fb_helper_cfb_fillrect(struct fb_info *info,
 260                                 const struct fb_fillrect *rect);
 261 void drm_fb_helper_cfb_copyarea(struct fb_info *info,
 262                                 const struct fb_copyarea *area);
 263 void drm_fb_helper_cfb_imageblit(struct fb_info *info,
 264                                  const struct fb_image *image);
 265
 266 void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, int state);
 267
 268 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info);
 269
 270 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper);
 271 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel);
 272 int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper);
 273 int drm_fb_helper_debug_enter(struct fb_info *info);
 274 int drm_fb_helper_debug_leave(struct fb_info *info);
 275 struct drm_display_mode *
 276 drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector,
 277                         int width, int height);
 278 struct drm_display_mode *
 279 drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
 280                       int width, int height);
 281
 282 int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper, struct drm_connector *connector);
 283 int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 284                                        struct drm_connector *connector);
 285 #else
 286 static inline void drm_fb_helper_prepare(struct drm_device *dev,
 287                                         struct drm_fb_helper *helper,
 288                                         const struct drm_fb_helper_funcs *funcs)
 289 {
 290 }
 291
 292 static inline int drm_fb_helper_init(struct drm_device *dev,
 293                        struct drm_fb_helper *helper, int crtc_count,
 294                        int max_conn)
 295 {
 296         return 0;
 297 }
 298
 299 static inline void drm_fb_helper_fini(struct drm_fb_helper *helper)
 300 {
 301 }
 302
 303 static inline int drm_fb_helper_blank(int blank, struct fb_info *info)
 304 {
 305         return 0;
 306 }
 307
 308 static inline int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
 309                                             struct fb_info *info)
 310 {
 311         return 0;
 312 }
 313
 314 static inline int drm_fb_helper_set_par(struct fb_info *info)
 315 {
 316         return 0;
 317 }
 318
 319 static inline int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
 320                                           struct fb_info *info)
 321 {
 322         return 0;
 323 }
 324
 325 static inline int
 326 drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
 327 {
 328         return 0;
 329 }
 330
 331 static inline struct fb_info *
 332 drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper)
 333 {
 334         return NULL;
 335 }
 336
 337 static inline void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper)
 338 {
 339 }
 340 static inline void drm_fb_helper_release_fbi(struct drm_fb_helper *fb_helper)
 341 {
 342 }
 343
 344 static inline void drm_fb_helper_fill_var(struct fb_info *info,
 345                                           struct drm_fb_helper *fb_helper,
 346                                           uint32_t fb_width, uint32_t fb_height)
 347 {
 348 }
 349
 350 static inline void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
 351                                           uint32_t depth)
 352 {
 353 }
 354
 355 static inline int drm_fb_helper_setcmap(struct fb_cmap *cmap,
 356                                         struct fb_info *info)
 357 {
 358         return 0;
 359 }
 360
 361 static inline void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper)
 362 {
 363 }
 364
 365 static inline ssize_t drm_fb_helper_sys_read(struct fb_info *info,
 366                                              char __user *buf, size_t count,
 367                                              loff_t *ppos)
 368 {
 369         return -ENODEV;
 370 }
 371
 372 static inline ssize_t drm_fb_helper_sys_write(struct fb_info *info,
 373                                               const char __user *buf,
 374                                               size_t count, loff_t *ppos)
 375 {
 376         return -ENODEV;
 377 }
 378
 379 static inline void drm_fb_helper_sys_fillrect(struct fb_info *info,
 380                                               const struct fb_fillrect *rect)
 381 {
 382 }
 383
 384 static inline void drm_fb_helper_sys_copyarea(struct fb_info *info,
 385                                               const struct fb_copyarea *area)
 386 {
 387 }
 388
 389 static inline void drm_fb_helper_sys_imageblit(struct fb_info *info,
 390                                                const struct fb_image *image)
 391 {
 392 }
 393
 394 static inline void drm_fb_helper_cfb_fillrect(struct fb_info *info,
 395                                               const struct fb_fillrect *rect)
 396 {
 397 }
 398
 399 static inline void drm_fb_helper_cfb_copyarea(struct fb_info *info,
 400                                               const struct fb_copyarea *area)
 401 {
 402 }
 403
 404 static inline void drm_fb_helper_cfb_imageblit(struct fb_info *info,
 405                                                const struct fb_image *image)
 406 {
 407 }
 408
 409 static inline void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper,
 410                                              int state)
 411 {
 412 }
 413
 414 static inline int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
 415 {
 416         return 0;
 417 }
 418
 419 static inline int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper,
 420                                                int bpp_sel)
 421 {
 422         return 0;
 423 }
 424
 425 static inline int
 426 drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
 427 {
 428         return 0;
 429 }
 430
 431 static inline int drm_fb_helper_debug_enter(struct fb_info *info)
 432 {
 433         return 0;
 434 }
 435
 436 static inline int drm_fb_helper_debug_leave(struct fb_info *info)
 437 {
 438         return 0;
 439 }
 440
 441 static inline struct drm_display_mode *
 442 drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector,
 443                        int width, int height)
 444 {
 445         return NULL;
 446 }
 447
 448 static inline struct drm_display_mode *
 449 drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
 450                       int width, int height)
 451 {
 452         return NULL;
 453 }
 454
 455 static inline int
 456 drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper,
 457                                 struct drm_connector *connector)
 458 {
 459         return 0;
 460 }
 461
 462 static inline int
 463 drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 464                                    struct drm_connector *connector)
 465 {
 466         return 0;
 467 }
 468 #endif
 469 #endif