drivers/gpu/drm/tiny/simpledrm.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2
   3 #include <linux/clk.h>
   4 #include <linux/of_clk.h>
   5 #include <linux/minmax.h>
   6 #include <linux/of_address.h>
   7 #include <linux/platform_data/simplefb.h>
   8 #include <linux/platform_device.h>
   9 #include <linux/pm_domain.h>
  10 #include <linux/regulator/consumer.h>
  11
  12 #include <drm/drm_aperture.h>
  13 #include <drm/drm_atomic.h>
  14 #include <drm/drm_atomic_state_helper.h>
  15 #include <drm/drm_connector.h>
  16 #include <drm/drm_crtc_helper.h>
  17 #include <drm/drm_damage_helper.h>
  18 #include <drm/drm_device.h>
  19 #include <drm/drm_drv.h>
  20 #include <drm/drm_fbdev_generic.h>
  21 #include <drm/drm_format_helper.h>
  22 #include <drm/drm_gem_atomic_helper.h>
  23 #include <drm/drm_gem_framebuffer_helper.h>
  24 #include <drm/drm_gem_shmem_helper.h>
  25 #include <drm/drm_managed.h>
  26 #include <drm/drm_modeset_helper_vtables.h>
  27 #include <drm/drm_plane_helper.h>
  28 #include <drm/drm_probe_helper.h>
  29
  30 #define DRIVER_NAME     "simpledrm"
  31 #define DRIVER_DESC     "DRM driver for simple-framebuffer platform devices"
  32 #define DRIVER_DATE     "20200625"
  33 #define DRIVER_MAJOR    1
  34 #define DRIVER_MINOR    0
  35
  36 /*
  37  * Helpers for simplefb
  38  */
  39
  40 static int
  41 simplefb_get_validated_int(struct drm_device *dev, const char *name,
  42                            uint32_t value)
  43 {
  44         if (value > INT_MAX) {
  45                 drm_err(dev, "simplefb: invalid framebuffer %s of %u\n",
  46                         name, value);
  47                 return -EINVAL;
  48         }
  49         return (int)value;
  50 }
  51
  52 static int
  53 simplefb_get_validated_int0(struct drm_device *dev, const char *name,
  54                             uint32_t value)
  55 {
  56         if (!value) {
  57                 drm_err(dev, "simplefb: invalid framebuffer %s of %u\n",
  58                         name, value);
  59                 return -EINVAL;
  60         }
  61         return simplefb_get_validated_int(dev, name, value);
  62 }
  63
  64 static const struct drm_format_info *
  65 simplefb_get_validated_format(struct drm_device *dev, const char *format_name)
  66 {
  67         static const struct simplefb_format formats[] = SIMPLEFB_FORMATS;
  68         const struct simplefb_format *fmt = formats;
  69         const struct simplefb_format *end = fmt + ARRAY_SIZE(formats);
  70         const struct drm_format_info *info;
  71
  72         if (!format_name) {
  73                 drm_err(dev, "simplefb: missing framebuffer format\n");
  74                 return ERR_PTR(-EINVAL);
  75         }
  76
  77         while (fmt < end) {
  78                 if (!strcmp(format_name, fmt->name)) {
  79                         info = drm_format_info(fmt->fourcc);
  80                         if (!info)
  81                                 return ERR_PTR(-EINVAL);
  82                         return info;
  83                 }
  84                 ++fmt;
  85         }
  86
  87         drm_err(dev, "simplefb: unknown framebuffer format %s\n",
  88                 format_name);
  89
  90         return ERR_PTR(-EINVAL);
  91 }
  92
  93 static int
  94 simplefb_get_width_pd(struct drm_device *dev,
  95                       const struct simplefb_platform_data *pd)
  96 {
  97         return simplefb_get_validated_int0(dev, "width", pd->width);
  98 }
  99
 100 static int
 101 simplefb_get_height_pd(struct drm_device *dev,
 102                        const struct simplefb_platform_data *pd)
 103 {
 104         return simplefb_get_validated_int0(dev, "height", pd->height);
 105 }
 106
 107 static int
 108 simplefb_get_stride_pd(struct drm_device *dev,
 109                        const struct simplefb_platform_data *pd)
 110 {
 111         return simplefb_get_validated_int(dev, "stride", pd->stride);
 112 }
 113
 114 static const struct drm_format_info *
 115 simplefb_get_format_pd(struct drm_device *dev,
 116                        const struct simplefb_platform_data *pd)
 117 {
 118         return simplefb_get_validated_format(dev, pd->format);
 119 }
 120
 121 static int
 122 simplefb_read_u32_of(struct drm_device *dev, struct device_node *of_node,
 123                      const char *name, u32 *value)
 124 {
 125         int ret = of_property_read_u32(of_node, name, value);
 126
 127         if (ret)
 128                 drm_err(dev, "simplefb: cannot parse framebuffer %s: error %d\n",
 129                         name, ret);
 130         return ret;
 131 }
 132
 133 static int
 134 simplefb_read_string_of(struct drm_device *dev, struct device_node *of_node,
 135                         const char *name, const char **value)
 136 {
 137         int ret = of_property_read_string(of_node, name, value);
 138
 139         if (ret)
 140                 drm_err(dev, "simplefb: cannot parse framebuffer %s: error %d\n",
 141                         name, ret);
 142         return ret;
 143 }
 144
 145 static int
 146 simplefb_get_width_of(struct drm_device *dev, struct device_node *of_node)
 147 {
 148         u32 width;
 149         int ret = simplefb_read_u32_of(dev, of_node, "width", &width);
 150
 151         if (ret)
 152                 return ret;
 153         return simplefb_get_validated_int0(dev, "width", width);
 154 }
 155
 156 static int
 157 simplefb_get_height_of(struct drm_device *dev, struct device_node *of_node)
 158 {
 159         u32 height;
 160         int ret = simplefb_read_u32_of(dev, of_node, "height", &height);
 161
 162         if (ret)
 163                 return ret;
 164         return simplefb_get_validated_int0(dev, "height", height);
 165 }
 166
 167 static int
 168 simplefb_get_stride_of(struct drm_device *dev, struct device_node *of_node)
 169 {
 170         u32 stride;
 171         int ret = simplefb_read_u32_of(dev, of_node, "stride", &stride);
 172
 173         if (ret)
 174                 return ret;
 175         return simplefb_get_validated_int(dev, "stride", stride);
 176 }
 177
 178 static const struct drm_format_info *
 179 simplefb_get_format_of(struct drm_device *dev, struct device_node *of_node)
 180 {
 181         const char *format;
 182         int ret = simplefb_read_string_of(dev, of_node, "format", &format);
 183
 184         if (ret)
 185                 return ERR_PTR(ret);
 186         return simplefb_get_validated_format(dev, format);
 187 }
 188
 189 static struct resource *
 190 simplefb_get_memory_of(struct drm_device *dev, struct device_node *of_node)
 191 {
 192         struct device_node *np;
 193         struct resource *res;
 194         int err;
 195
 196         np = of_parse_phandle(of_node, "memory-region", 0);
 197         if (!np)
 198                 return NULL;
 199
 200         res = devm_kzalloc(dev->dev, sizeof(*res), GFP_KERNEL);
 201         if (!res)
 202                 return ERR_PTR(-ENOMEM);
 203
 204         err = of_address_to_resource(np, 0, res);
 205         if (err)
 206                 return ERR_PTR(err);
 207
 208         if (of_property_present(of_node, "reg"))
 209                 drm_warn(dev, "preferring \"memory-region\" over \"reg\" property\n");
 210
 211         return res;
 212 }
 213
 214 /*
 215  * Simple Framebuffer device
 216  */
 217
 218 struct simpledrm_device {
 219         struct drm_device dev;
 220
 221         /* clocks */
 222 #if defined CONFIG_OF && defined CONFIG_COMMON_CLK
 223         unsigned int clk_count;
 224         struct clk **clks;
 225 #endif
 226         /* regulators */
 227 #if defined CONFIG_OF && defined CONFIG_REGULATOR
 228         unsigned int regulator_count;
 229         struct regulator **regulators;
 230 #endif
 231         /* power-domains */
 232 #if defined CONFIG_OF && defined CONFIG_PM_GENERIC_DOMAINS
 233         int pwr_dom_count;
 234         struct device **pwr_dom_devs;
 235         struct device_link **pwr_dom_links;
 236 #endif
 237
 238         /* simplefb settings */
 239         struct drm_display_mode mode;
 240         const struct drm_format_info *format;
 241         unsigned int pitch;
 242
 243         /* memory management */
 244         struct iosys_map screen_base;
 245
 246         /* modesetting */
 247         uint32_t formats[8];
 248         size_t nformats;
 249         struct drm_plane primary_plane;
 250         struct drm_crtc crtc;
 251         struct drm_encoder encoder;
 252         struct drm_connector connector;
 253 };
 254
 255 static struct simpledrm_device *simpledrm_device_of_dev(struct drm_device *dev)
 256 {
 257         return container_of(dev, struct simpledrm_device, dev);
 258 }
 259
 260 /*
 261  * Hardware
 262  */
 263
 264 #if defined CONFIG_OF && defined CONFIG_COMMON_CLK
 265 /*
 266  * Clock handling code.
 267  *
 268  * Here we handle the clocks property of our "simple-framebuffer" dt node.
 269  * This is necessary so that we can make sure that any clocks needed by
 270  * the display engine that the bootloader set up for us (and for which it
 271  * provided a simplefb dt node), stay up, for the life of the simplefb
 272  * driver.
 273  *
 274  * When the driver unloads, we cleanly disable, and then release the clocks.
 275  *
 276  * We only complain about errors here, no action is taken as the most likely
 277  * error can only happen due to a mismatch between the bootloader which set
 278  * up simplefb, and the clock definitions in the device tree. Chances are
 279  * that there are no adverse effects, and if there are, a clean teardown of
 280  * the fb probe will not help us much either. So just complain and carry on,
 281  * and hope that the user actually gets a working fb at the end of things.
 282  */
 283
 284 static void simpledrm_device_release_clocks(void *res)
 285 {
 286         struct simpledrm_device *sdev = simpledrm_device_of_dev(res);
 287         unsigned int i;
 288
 289         for (i = 0; i < sdev->clk_count; ++i) {
 290                 if (sdev->clks[i]) {
 291                         clk_disable_unprepare(sdev->clks[i]);
 292                         clk_put(sdev->clks[i]);
 293                 }
 294         }
 295 }
 296
 297 static int simpledrm_device_init_clocks(struct simpledrm_device *sdev)
 298 {
 299         struct drm_device *dev = &sdev->dev;
 300         struct platform_device *pdev = to_platform_device(dev->dev);
 301         struct device_node *of_node = pdev->dev.of_node;
 302         struct clk *clock;
 303         unsigned int i;
 304         int ret;
 305
 306         if (dev_get_platdata(&pdev->dev) || !of_node)
 307                 return 0;
 308
 309         sdev->clk_count = of_clk_get_parent_count(of_node);
 310         if (!sdev->clk_count)
 311                 return 0;
 312
 313         sdev->clks = drmm_kzalloc(dev, sdev->clk_count * sizeof(sdev->clks[0]),
 314                                   GFP_KERNEL);
 315         if (!sdev->clks)
 316                 return -ENOMEM;
 317
 318         for (i = 0; i < sdev->clk_count; ++i) {
 319                 clock = of_clk_get(of_node, i);
 320                 if (IS_ERR(clock)) {
 321                         ret = PTR_ERR(clock);
 322                         if (ret == -EPROBE_DEFER)
 323                                 goto err;
 324                         drm_err(dev, "clock %u not found: %d\n", i, ret);
 325                         continue;
 326                 }
 327                 ret = clk_prepare_enable(clock);
 328                 if (ret) {
 329                         drm_err(dev, "failed to enable clock %u: %d\n",
 330                                 i, ret);
 331                         clk_put(clock);
 332                         continue;
 333                 }
 334                 sdev->clks[i] = clock;
 335         }
 336
 337         return devm_add_action_or_reset(&pdev->dev,
 338                                         simpledrm_device_release_clocks,
 339                                         sdev);
 340
 341 err:
 342         while (i) {
 343                 --i;
 344                 if (sdev->clks[i]) {
 345                         clk_disable_unprepare(sdev->clks[i]);
 346                         clk_put(sdev->clks[i]);
 347                 }
 348         }
 349         return ret;
 350 }
 351 #else
 352 static int simpledrm_device_init_clocks(struct simpledrm_device *sdev)
 353 {
 354         return 0;
 355 }
 356 #endif
 357
 358 #if defined CONFIG_OF && defined CONFIG_REGULATOR
 359
 360 #define SUPPLY_SUFFIX "-supply"
 361
 362 /*
 363  * Regulator handling code.
 364  *
 365  * Here we handle the num-supplies and vin*-supply properties of our
 366  * "simple-framebuffer" dt node. This is necessary so that we can make sure
 367  * that any regulators needed by the display hardware that the bootloader
 368  * set up for us (and for which it provided a simplefb dt node), stay up,
 369  * for the life of the simplefb driver.
 370  *
 371  * When the driver unloads, we cleanly disable, and then release the
 372  * regulators.
 373  *
 374  * We only complain about errors here, no action is taken as the most likely
 375  * error can only happen due to a mismatch between the bootloader which set
 376  * up simplefb, and the regulator definitions in the device tree. Chances are
 377  * that there are no adverse effects, and if there are, a clean teardown of
 378  * the fb probe will not help us much either. So just complain and carry on,
 379  * and hope that the user actually gets a working fb at the end of things.
 380  */
 381
 382 static void simpledrm_device_release_regulators(void *res)
 383 {
 384         struct simpledrm_device *sdev = simpledrm_device_of_dev(res);
 385         unsigned int i;
 386
 387         for (i = 0; i < sdev->regulator_count; ++i) {
 388                 if (sdev->regulators[i]) {
 389                         regulator_disable(sdev->regulators[i]);
 390                         regulator_put(sdev->regulators[i]);
 391                 }
 392         }
 393 }
 394
 395 static int simpledrm_device_init_regulators(struct simpledrm_device *sdev)
 396 {
 397         struct drm_device *dev = &sdev->dev;
 398         struct platform_device *pdev = to_platform_device(dev->dev);
 399         struct device_node *of_node = pdev->dev.of_node;
 400         struct property *prop;
 401         struct regulator *regulator;
 402         const char *p;
 403         unsigned int count = 0, i = 0;
 404         int ret;
 405
 406         if (dev_get_platdata(&pdev->dev) || !of_node)
 407                 return 0;
 408
 409         /* Count the number of regulator supplies */
 410         for_each_property_of_node(of_node, prop) {
 411                 p = strstr(prop->name, SUPPLY_SUFFIX);
 412                 if (p && p != prop->name)
 413                         ++count;
 414         }
 415
 416         if (!count)
 417                 return 0;
 418
 419         sdev->regulators = drmm_kzalloc(dev,
 420                                         count * sizeof(sdev->regulators[0]),
 421                                         GFP_KERNEL);
 422         if (!sdev->regulators)
 423                 return -ENOMEM;
 424
 425         for_each_property_of_node(of_node, prop) {
 426                 char name[32]; /* 32 is max size of property name */
 427                 size_t len;
 428
 429                 p = strstr(prop->name, SUPPLY_SUFFIX);
 430                 if (!p || p == prop->name)
 431                         continue;
 432                 len = strlen(prop->name) - strlen(SUPPLY_SUFFIX) + 1;
 433                 strscpy(name, prop->name, min(sizeof(name), len));
 434
 435                 regulator = regulator_get_optional(&pdev->dev, name);
 436                 if (IS_ERR(regulator)) {
 437                         ret = PTR_ERR(regulator);
 438                         if (ret == -EPROBE_DEFER)
 439                                 goto err;
 440                         drm_err(dev, "regulator %s not found: %d\n",
 441                                 name, ret);
 442                         continue;
 443                 }
 444
 445                 ret = regulator_enable(regulator);
 446                 if (ret) {
 447                         drm_err(dev, "failed to enable regulator %u: %d\n",
 448                                 i, ret);
 449                         regulator_put(regulator);
 450                         continue;
 451                 }
 452
 453                 sdev->regulators[i++] = regulator;
 454         }
 455         sdev->regulator_count = i;
 456
 457         return devm_add_action_or_reset(&pdev->dev,
 458                                         simpledrm_device_release_regulators,
 459                                         sdev);
 460
 461 err:
 462         while (i) {
 463                 --i;
 464                 if (sdev->regulators[i]) {
 465                         regulator_disable(sdev->regulators[i]);
 466                         regulator_put(sdev->regulators[i]);
 467                 }
 468         }
 469         return ret;
 470 }
 471 #else
 472 static int simpledrm_device_init_regulators(struct simpledrm_device *sdev)
 473 {
 474         return 0;
 475 }
 476 #endif
 477
 478 #if defined CONFIG_OF && defined CONFIG_PM_GENERIC_DOMAINS
 479 /*
 480  * Generic power domain handling code.
 481  *
 482  * Here we handle the power-domains properties of our "simple-framebuffer"
 483  * dt node. This is only necessary if there is more than one power-domain.
 484  * A single power-domains is handled automatically by the driver core. Multiple
 485  * power-domains have to be handled by drivers since the driver core can't know
 486  * the correct power sequencing. Power sequencing is not an issue for simpledrm
 487  * since the bootloader has put the power domains already in the correct state.
 488  * simpledrm has only to ensure they remain active for its lifetime.
 489  *
 490  * When the driver unloads, we detach from the power-domains.
 491  *
 492  * We only complain about errors here, no action is taken as the most likely
 493  * error can only happen due to a mismatch between the bootloader which set
 494  * up the "simple-framebuffer" dt node, and the PM domain providers in the
 495  * device tree. Chances are that there are no adverse effects, and if there are,
 496  * a clean teardown of the fb probe will not help us much either. So just
 497  * complain and carry on, and hope that the user actually gets a working fb at
 498  * the end of things.
 499  */
 500 static void simpledrm_device_detach_genpd(void *res)
 501 {
 502         int i;
 503         struct simpledrm_device *sdev = res;
 504
 505         if (sdev->pwr_dom_count <= 1)
 506                 return;
 507
 508         for (i = sdev->pwr_dom_count - 1; i >= 0; i--) {
 509                 if (sdev->pwr_dom_links[i])
 510                         device_link_del(sdev->pwr_dom_links[i]);
 511                 if (!IS_ERR_OR_NULL(sdev->pwr_dom_devs[i]))
 512                         dev_pm_domain_detach(sdev->pwr_dom_devs[i], true);
 513         }
 514 }
 515
 516 static int simpledrm_device_attach_genpd(struct simpledrm_device *sdev)
 517 {
 518         struct device *dev = sdev->dev.dev;
 519         int i;
 520
 521         sdev->pwr_dom_count = of_count_phandle_with_args(dev->of_node, "power-domains",
 522                                                          "#power-domain-cells");
 523         /*
 524          * Single power-domain devices are handled by driver core nothing to do
 525          * here. The same for device nodes without "power-domains" property.
 526          */
 527         if (sdev->pwr_dom_count <= 1)
 528                 return 0;
 529
 530         sdev->pwr_dom_devs = devm_kcalloc(dev, sdev->pwr_dom_count,
 531                                                sizeof(*sdev->pwr_dom_devs),
 532                                                GFP_KERNEL);
 533         if (!sdev->pwr_dom_devs)
 534                 return -ENOMEM;
 535
 536         sdev->pwr_dom_links = devm_kcalloc(dev, sdev->pwr_dom_count,
 537                                                 sizeof(*sdev->pwr_dom_links),
 538                                                 GFP_KERNEL);
 539         if (!sdev->pwr_dom_links)
 540                 return -ENOMEM;
 541
 542         for (i = 0; i < sdev->pwr_dom_count; i++) {
 543                 sdev->pwr_dom_devs[i] = dev_pm_domain_attach_by_id(dev, i);
 544                 if (IS_ERR(sdev->pwr_dom_devs[i])) {
 545                         int ret = PTR_ERR(sdev->pwr_dom_devs[i]);
 546                         if (ret == -EPROBE_DEFER) {
 547                                 simpledrm_device_detach_genpd(sdev);
 548                                 return ret;
 549                         }
 550                         drm_warn(&sdev->dev,
 551                                  "pm_domain_attach_by_id(%u) failed: %d\n", i, ret);
 552                         continue;
 553                 }
 554
 555                 sdev->pwr_dom_links[i] = device_link_add(dev,
 556                                                          sdev->pwr_dom_devs[i],
 557                                                          DL_FLAG_STATELESS |
 558                                                          DL_FLAG_PM_RUNTIME |
 559                                                          DL_FLAG_RPM_ACTIVE);
 560                 if (!sdev->pwr_dom_links[i])
 561                         drm_warn(&sdev->dev, "failed to link power-domain %d\n", i);
 562         }
 563
 564         return devm_add_action_or_reset(dev, simpledrm_device_detach_genpd, sdev);
 565 }
 566 #else
 567 static int simpledrm_device_attach_genpd(struct simpledrm_device *sdev)
 568 {
 569         return 0;
 570 }
 571 #endif
 572
 573 /*
 574  * Modesetting
 575  */
 576
 577 static const uint64_t simpledrm_primary_plane_format_modifiers[] = {
 578         DRM_FORMAT_MOD_LINEAR,
 579         DRM_FORMAT_MOD_INVALID
 580 };
 581
 582 static void simpledrm_primary_plane_helper_atomic_update(struct drm_plane *plane,
 583                                                          struct drm_atomic_state *state)
 584 {
 585         struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state, plane);
 586         struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(state, plane);
 587         struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
 588         struct drm_framebuffer *fb = plane_state->fb;
 589         struct drm_device *dev = plane->dev;
 590         struct simpledrm_device *sdev = simpledrm_device_of_dev(dev);
 591         struct drm_atomic_helper_damage_iter iter;
 592         struct drm_rect damage;
 593         int ret, idx;
 594
 595         ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
 596         if (ret)
 597                 return;
 598
 599         if (!drm_dev_enter(dev, &idx))
 600                 goto out_drm_gem_fb_end_cpu_access;
 601
 602         drm_atomic_helper_damage_iter_init(&iter, old_plane_state, plane_state);
 603         drm_atomic_for_each_plane_damage(&iter, &damage) {
 604                 struct drm_rect dst_clip = plane_state->dst;
 605                 struct iosys_map dst = sdev->screen_base;
 606
 607                 if (!drm_rect_intersect(&dst_clip, &damage))
 608                         continue;
 609
 610                 iosys_map_incr(&dst, drm_fb_clip_offset(sdev->pitch, sdev->format, &dst_clip));
 611                 drm_fb_blit(&dst, &sdev->pitch, sdev->format->format, shadow_plane_state->data,
 612                             fb, &damage);
 613         }
 614
 615         drm_dev_exit(idx);
 616 out_drm_gem_fb_end_cpu_access:
 617         drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
 618 }
 619
 620 static void simpledrm_primary_plane_helper_atomic_disable(struct drm_plane *plane,
 621                                                           struct drm_atomic_state *state)
 622 {
 623         struct drm_device *dev = plane->dev;
 624         struct simpledrm_device *sdev = simpledrm_device_of_dev(dev);
 625         int idx;
 626
 627         if (!drm_dev_enter(dev, &idx))
 628                 return;
 629
 630         /* Clear screen to black if disabled */
 631         iosys_map_memset(&sdev->screen_base, 0, 0, sdev->pitch * sdev->mode.vdisplay);
 632
 633         drm_dev_exit(idx);
 634 }
 635
 636 static const struct drm_plane_helper_funcs simpledrm_primary_plane_helper_funcs = {
 637         DRM_GEM_SHADOW_PLANE_HELPER_FUNCS,
 638         .atomic_check = drm_plane_helper_atomic_check,
 639         .atomic_update = simpledrm_primary_plane_helper_atomic_update,
 640         .atomic_disable = simpledrm_primary_plane_helper_atomic_disable,
 641 };
 642
 643 static const struct drm_plane_funcs simpledrm_primary_plane_funcs = {
 644         .update_plane = drm_atomic_helper_update_plane,
 645         .disable_plane = drm_atomic_helper_disable_plane,
 646         .destroy = drm_plane_cleanup,
 647         DRM_GEM_SHADOW_PLANE_FUNCS,
 648 };
 649
 650 static enum drm_mode_status simpledrm_crtc_helper_mode_valid(struct drm_crtc *crtc,
 651                                                              const struct drm_display_mode *mode)
 652 {
 653         struct simpledrm_device *sdev = simpledrm_device_of_dev(crtc->dev);
 654
 655         return drm_crtc_helper_mode_valid_fixed(crtc, mode, &sdev->mode);
 656 }
 657
 658 /*
 659  * The CRTC is always enabled. Screen updates are performed by
 660  * the primary plane's atomic_update function. Disabling clears
 661  * the screen in the primary plane's atomic_disable function.
 662  */
 663 static const struct drm_crtc_helper_funcs simpledrm_crtc_helper_funcs = {
 664         .mode_valid = simpledrm_crtc_helper_mode_valid,
 665         .atomic_check = drm_crtc_helper_atomic_check,
 666 };
 667
 668 static const struct drm_crtc_funcs simpledrm_crtc_funcs = {
 669         .reset = drm_atomic_helper_crtc_reset,
 670         .destroy = drm_crtc_cleanup,
 671         .set_config = drm_atomic_helper_set_config,
 672         .page_flip = drm_atomic_helper_page_flip,
 673         .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
 674         .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
 675 };
 676
 677 static const struct drm_encoder_funcs simpledrm_encoder_funcs = {
 678         .destroy = drm_encoder_cleanup,
 679 };
 680
 681 static int simpledrm_connector_helper_get_modes(struct drm_connector *connector)
 682 {
 683         struct simpledrm_device *sdev = simpledrm_device_of_dev(connector->dev);
 684
 685         return drm_connector_helper_get_modes_fixed(connector, &sdev->mode);
 686 }
 687
 688 static const struct drm_connector_helper_funcs simpledrm_connector_helper_funcs = {
 689         .get_modes = simpledrm_connector_helper_get_modes,
 690 };
 691
 692 static const struct drm_connector_funcs simpledrm_connector_funcs = {
 693         .reset = drm_atomic_helper_connector_reset,
 694         .fill_modes = drm_helper_probe_single_connector_modes,
 695         .destroy = drm_connector_cleanup,
 696         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 697         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 698 };
 699
 700 static const struct drm_mode_config_funcs simpledrm_mode_config_funcs = {
 701         .fb_create = drm_gem_fb_create_with_dirty,
 702         .atomic_check = drm_atomic_helper_check,
 703         .atomic_commit = drm_atomic_helper_commit,
 704 };
 705
 706 /*
 707  * Init / Cleanup
 708  */
 709
 710 static struct drm_display_mode simpledrm_mode(unsigned int width,
 711                                               unsigned int height,
 712                                               unsigned int width_mm,
 713                                               unsigned int height_mm)
 714 {
 715         const struct drm_display_mode mode = {
 716                 DRM_MODE_INIT(60, width, height, width_mm, height_mm)
 717         };
 718
 719         return mode;
 720 }
 721
 722 static struct simpledrm_device *simpledrm_device_create(struct drm_driver *drv,
 723                                                         struct platform_device *pdev)
 724 {
 725         const struct simplefb_platform_data *pd = dev_get_platdata(&pdev->dev);
 726         struct device_node *of_node = pdev->dev.of_node;
 727         struct simpledrm_device *sdev;
 728         struct drm_device *dev;
 729         int width, height, stride;
 730         int width_mm = 0, height_mm = 0;
 731         struct device_node *panel_node;
 732         const struct drm_format_info *format;
 733         struct resource *res, *mem = NULL;
 734         struct drm_plane *primary_plane;
 735         struct drm_crtc *crtc;
 736         struct drm_encoder *encoder;
 737         struct drm_connector *connector;
 738         unsigned long max_width, max_height;
 739         size_t nformats;
 740         int ret;
 741
 742         sdev = devm_drm_dev_alloc(&pdev->dev, drv, struct simpledrm_device, dev);
 743         if (IS_ERR(sdev))
 744                 return ERR_CAST(sdev);
 745         dev = &sdev->dev;
 746         platform_set_drvdata(pdev, sdev);
 747
 748         /*
 749          * Hardware settings
 750          */
 751
 752         ret = simpledrm_device_init_clocks(sdev);
 753         if (ret)
 754                 return ERR_PTR(ret);
 755         ret = simpledrm_device_init_regulators(sdev);
 756         if (ret)
 757                 return ERR_PTR(ret);
 758         ret = simpledrm_device_attach_genpd(sdev);
 759         if (ret)
 760                 return ERR_PTR(ret);
 761
 762         if (pd) {
 763                 width = simplefb_get_width_pd(dev, pd);
 764                 if (width < 0)
 765                         return ERR_PTR(width);
 766                 height = simplefb_get_height_pd(dev, pd);
 767                 if (height < 0)
 768                         return ERR_PTR(height);
 769                 stride = simplefb_get_stride_pd(dev, pd);
 770                 if (stride < 0)
 771                         return ERR_PTR(stride);
 772                 format = simplefb_get_format_pd(dev, pd);
 773                 if (IS_ERR(format))
 774                         return ERR_CAST(format);
 775         } else if (of_node) {
 776                 width = simplefb_get_width_of(dev, of_node);
 777                 if (width < 0)
 778                         return ERR_PTR(width);
 779                 height = simplefb_get_height_of(dev, of_node);
 780                 if (height < 0)
 781                         return ERR_PTR(height);
 782                 stride = simplefb_get_stride_of(dev, of_node);
 783                 if (stride < 0)
 784                         return ERR_PTR(stride);
 785                 format = simplefb_get_format_of(dev, of_node);
 786                 if (IS_ERR(format))
 787                         return ERR_CAST(format);
 788                 mem = simplefb_get_memory_of(dev, of_node);
 789                 if (IS_ERR(mem))
 790                         return ERR_CAST(mem);
 791                 panel_node = of_parse_phandle(of_node, "panel", 0);
 792                 if (panel_node) {
 793                         simplefb_read_u32_of(dev, panel_node, "width-mm", &width_mm);
 794                         simplefb_read_u32_of(dev, panel_node, "height-mm", &height_mm);
 795                         of_node_put(panel_node);
 796                 }
 797         } else {
 798                 drm_err(dev, "no simplefb configuration found\n");
 799                 return ERR_PTR(-ENODEV);
 800         }
 801         if (!stride) {
 802                 stride = drm_format_info_min_pitch(format, 0, width);
 803                 if (drm_WARN_ON(dev, !stride))
 804                         return ERR_PTR(-EINVAL);
 805         }
 806
 807         /*
 808          * Assume a monitor resolution of 96 dpi if physical dimensions
 809          * are not specified to get a somewhat reasonable screen size.
 810          */
 811         if (!width_mm)
 812                 width_mm = DRM_MODE_RES_MM(width, 96ul);
 813         if (!height_mm)
 814                 height_mm = DRM_MODE_RES_MM(height, 96ul);
 815
 816         sdev->mode = simpledrm_mode(width, height, width_mm, height_mm);
 817         sdev->format = format;
 818         sdev->pitch = stride;
 819
 820         drm_dbg(dev, "display mode={" DRM_MODE_FMT "}\n", DRM_MODE_ARG(&sdev->mode));
 821         drm_dbg(dev, "framebuffer format=%p4cc, size=%dx%d, stride=%d byte\n",
 822                 &format->format, width, height, stride);
 823
 824         /*
 825          * Memory management
 826          */
 827
 828         if (mem) {
 829                 void *screen_base;
 830
 831                 ret = devm_aperture_acquire_from_firmware(dev, mem->start, resource_size(mem));
 832                 if (ret) {
 833                         drm_err(dev, "could not acquire memory range %pr: %d\n", mem, ret);
 834                         return ERR_PTR(ret);
 835                 }
 836
 837                 drm_dbg(dev, "using system memory framebuffer at %pr\n", mem);
 838
 839                 screen_base = devm_memremap(dev->dev, mem->start, resource_size(mem), MEMREMAP_WC);
 840                 if (IS_ERR(screen_base))
 841                         return screen_base;
 842
 843                 iosys_map_set_vaddr(&sdev->screen_base, screen_base);
 844         } else {
 845                 void __iomem *screen_base;
 846
 847                 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 848                 if (!res)
 849                         return ERR_PTR(-EINVAL);
 850
 851                 ret = devm_aperture_acquire_from_firmware(dev, res->start, resource_size(res));
 852                 if (ret) {
 853                         drm_err(dev, "could not acquire memory range %pr: %d\n", res, ret);
 854                         return ERR_PTR(ret);
 855                 }
 856
 857                 drm_dbg(dev, "using I/O memory framebuffer at %pr\n", res);
 858
 859                 mem = devm_request_mem_region(&pdev->dev, res->start, resource_size(res),
 860                                               drv->name);
 861                 if (!mem) {
 862                         /*
 863                          * We cannot make this fatal. Sometimes this comes from magic
 864                          * spaces our resource handlers simply don't know about. Use
 865                          * the I/O-memory resource as-is and try to map that instead.
 866                          */
 867                         drm_warn(dev, "could not acquire memory region %pr\n", res);
 868                         mem = res;
 869                 }
 870
 871                 screen_base = devm_ioremap_wc(&pdev->dev, mem->start, resource_size(mem));
 872                 if (!screen_base)
 873                         return ERR_PTR(-ENOMEM);
 874
 875                 iosys_map_set_vaddr_iomem(&sdev->screen_base, screen_base);
 876         }
 877
 878         /*
 879          * Modesetting
 880          */
 881
 882         ret = drmm_mode_config_init(dev);
 883         if (ret)
 884                 return ERR_PTR(ret);
 885
 886         max_width = max_t(unsigned long, width, DRM_SHADOW_PLANE_MAX_WIDTH);
 887         max_height = max_t(unsigned long, height, DRM_SHADOW_PLANE_MAX_HEIGHT);
 888
 889         dev->mode_config.min_width = width;
 890         dev->mode_config.max_width = max_width;
 891         dev->mode_config.min_height = height;
 892         dev->mode_config.max_height = max_height;
 893         dev->mode_config.preferred_depth = format->depth;
 894         dev->mode_config.funcs = &simpledrm_mode_config_funcs;
 895
 896         /* Primary plane */
 897
 898         nformats = drm_fb_build_fourcc_list(dev, &format->format, 1,
 899                                             sdev->formats, ARRAY_SIZE(sdev->formats));
 900
 901         primary_plane = &sdev->primary_plane;
 902         ret = drm_universal_plane_init(dev, primary_plane, 0, &simpledrm_primary_plane_funcs,
 903                                        sdev->formats, nformats,
 904                                        simpledrm_primary_plane_format_modifiers,
 905                                        DRM_PLANE_TYPE_PRIMARY, NULL);
 906         if (ret)
 907                 return ERR_PTR(ret);
 908         drm_plane_helper_add(primary_plane, &simpledrm_primary_plane_helper_funcs);
 909         drm_plane_enable_fb_damage_clips(primary_plane);
 910
 911         /* CRTC */
 912
 913         crtc = &sdev->crtc;
 914         ret = drm_crtc_init_with_planes(dev, crtc, primary_plane, NULL,
 915                                         &simpledrm_crtc_funcs, NULL);
 916         if (ret)
 917                 return ERR_PTR(ret);
 918         drm_crtc_helper_add(crtc, &simpledrm_crtc_helper_funcs);
 919
 920         /* Encoder */
 921
 922         encoder = &sdev->encoder;
 923         ret = drm_encoder_init(dev, encoder, &simpledrm_encoder_funcs,
 924                                DRM_MODE_ENCODER_NONE, NULL);
 925         if (ret)
 926                 return ERR_PTR(ret);
 927         encoder->possible_crtcs = drm_crtc_mask(crtc);
 928
 929         /* Connector */
 930
 931         connector = &sdev->connector;
 932         ret = drm_connector_init(dev, connector, &simpledrm_connector_funcs,
 933                                  DRM_MODE_CONNECTOR_Unknown);
 934         if (ret)
 935                 return ERR_PTR(ret);
 936         drm_connector_helper_add(connector, &simpledrm_connector_helper_funcs);
 937         drm_connector_set_panel_orientation_with_quirk(connector,
 938                                                        DRM_MODE_PANEL_ORIENTATION_UNKNOWN,
 939                                                        width, height);
 940
 941         ret = drm_connector_attach_encoder(connector, encoder);
 942         if (ret)
 943                 return ERR_PTR(ret);
 944
 945         drm_mode_config_reset(dev);
 946
 947         return sdev;
 948 }
 949
 950 /*
 951  * DRM driver
 952  */
 953
 954 DEFINE_DRM_GEM_FOPS(simpledrm_fops);
 955
 956 static struct drm_driver simpledrm_driver = {
 957         DRM_GEM_SHMEM_DRIVER_OPS,
 958         .name                   = DRIVER_NAME,
 959         .desc                   = DRIVER_DESC,
 960         .date                   = DRIVER_DATE,
 961         .major                  = DRIVER_MAJOR,
 962         .minor                  = DRIVER_MINOR,
 963         .driver_features        = DRIVER_ATOMIC | DRIVER_GEM | DRIVER_MODESET,
 964         .fops                   = &simpledrm_fops,
 965 };
 966
 967 /*
 968  * Platform driver
 969  */
 970
 971 static int simpledrm_probe(struct platform_device *pdev)
 972 {
 973         struct simpledrm_device *sdev;
 974         struct drm_device *dev;
 975         unsigned int color_mode;
 976         int ret;
 977
 978         sdev = simpledrm_device_create(&simpledrm_driver, pdev);
 979         if (IS_ERR(sdev))
 980                 return PTR_ERR(sdev);
 981         dev = &sdev->dev;
 982
 983         ret = drm_dev_register(dev, 0);
 984         if (ret)
 985                 return ret;
 986
 987         color_mode = drm_format_info_bpp(sdev->format, 0);
 988         if (color_mode == 16)
 989                 color_mode = sdev->format->depth; // can be 15 or 16
 990
 991         drm_fbdev_generic_setup(dev, color_mode);
 992
 993         return 0;
 994 }
 995
 996 static void simpledrm_remove(struct platform_device *pdev)
 997 {
 998         struct simpledrm_device *sdev = platform_get_drvdata(pdev);
 999         struct drm_device *dev = &sdev->dev;
1000
1001         drm_dev_unplug(dev);
1002 }
1003
1004 static const struct of_device_id simpledrm_of_match_table[] = {
1005         { .compatible = "simple-framebuffer", },
1006         { },
1007 };
1008 MODULE_DEVICE_TABLE(of, simpledrm_of_match_table);
1009
1010 static struct platform_driver simpledrm_platform_driver = {
1011         .driver = {
1012                 .name = "simple-framebuffer", /* connect to sysfb */
1013                 .of_match_table = simpledrm_of_match_table,
1014         },
1015         .probe = simpledrm_probe,
1016         .remove_new = simpledrm_remove,
1017 };
1018
1019 module_platform_driver(simpledrm_platform_driver);
1020
1021 MODULE_DESCRIPTION(DRIVER_DESC);
1022 MODULE_LICENSE("GPL v2");