drivers/hwtracing/intel_th/core.c

   1 /*
   2  * Intel(R) Trace Hub driver core
   3  *
   4  * Copyright (C) 2014-2015 Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  */
  15
  16 #define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
  17
  18 #include <linux/types.h>
  19 #include <linux/module.h>
  20 #include <linux/device.h>
  21 #include <linux/sysfs.h>
  22 #include <linux/kdev_t.h>
  23 #include <linux/debugfs.h>
  24 #include <linux/idr.h>
  25 #include <linux/pci.h>
  26 #include <linux/pm_runtime.h>
  27 #include <linux/dma-mapping.h>
  28
  29 #include "intel_th.h"
  30 #include "debug.h"
  31
  32 static bool host_mode __read_mostly;
  33 module_param(host_mode, bool, 0444);
  34
  35 static DEFINE_IDA(intel_th_ida);
  36
  37 static int intel_th_match(struct device *dev, struct device_driver *driver)
  38 {
  39         struct intel_th_driver *thdrv = to_intel_th_driver(driver);
  40         struct intel_th_device *thdev = to_intel_th_device(dev);
  41
  42         if (thdev->type == INTEL_TH_SWITCH &&
  43             (!thdrv->enable || !thdrv->disable))
  44                 return 0;
  45
  46         return !strcmp(thdev->name, driver->name);
  47 }
  48
  49 static int intel_th_child_remove(struct device *dev, void *data)
  50 {
  51         device_release_driver(dev);
  52
  53         return 0;
  54 }
  55
  56 static int intel_th_probe(struct device *dev)
  57 {
  58         struct intel_th_driver *thdrv = to_intel_th_driver(dev->driver);
  59         struct intel_th_device *thdev = to_intel_th_device(dev);
  60         struct intel_th_driver *hubdrv;
  61         struct intel_th_device *hub = NULL;
  62         int ret;
  63
  64         if (thdev->type == INTEL_TH_SWITCH)
  65                 hub = thdev;
  66         else if (dev->parent)
  67                 hub = to_intel_th_device(dev->parent);
  68
  69         if (!hub || !hub->dev.driver)
  70                 return -EPROBE_DEFER;
  71
  72         hubdrv = to_intel_th_driver(hub->dev.driver);
  73
  74         pm_runtime_set_active(dev);
  75         pm_runtime_no_callbacks(dev);
  76         pm_runtime_enable(dev);
  77
  78         ret = thdrv->probe(to_intel_th_device(dev));
  79         if (ret)
  80                 goto out_pm;
  81
  82         if (thdrv->attr_group) {
  83                 ret = sysfs_create_group(&thdev->dev.kobj, thdrv->attr_group);
  84                 if (ret)
  85                         goto out;
  86         }
  87
  88         if (thdev->type == INTEL_TH_OUTPUT &&
  89             !intel_th_output_assigned(thdev))
  90                 /* does not talk to hardware */
  91                 ret = hubdrv->assign(hub, thdev);
  92
  93 out:
  94         if (ret)
  95                 thdrv->remove(thdev);
  96
  97 out_pm:
  98         if (ret)
  99                 pm_runtime_disable(dev);
 100
 101         return ret;
 102 }
 103
 104 static int intel_th_remove(struct device *dev)
 105 {
 106         struct intel_th_driver *thdrv = to_intel_th_driver(dev->driver);
 107         struct intel_th_device *thdev = to_intel_th_device(dev);
 108         struct intel_th_device *hub = to_intel_th_device(dev->parent);
 109         int err;
 110
 111         if (thdev->type == INTEL_TH_SWITCH) {
 112                 err = device_for_each_child(dev, thdev, intel_th_child_remove);
 113                 if (err)
 114                         return err;
 115         }
 116
 117         if (thdrv->attr_group)
 118                 sysfs_remove_group(&thdev->dev.kobj, thdrv->attr_group);
 119
 120         pm_runtime_get_sync(dev);
 121
 122         thdrv->remove(thdev);
 123
 124         if (intel_th_output_assigned(thdev)) {
 125                 struct intel_th_driver *hubdrv =
 126                         to_intel_th_driver(dev->parent->driver);
 127
 128                 if (hub->dev.driver)
 129                         /* does not talk to hardware */
 130                         hubdrv->unassign(hub, thdev);
 131         }
 132
 133         pm_runtime_disable(dev);
 134         pm_runtime_set_active(dev);
 135         pm_runtime_enable(dev);
 136
 137         return 0;
 138 }
 139
 140 static struct bus_type intel_th_bus = {
 141         .name           = "intel_th",
 142         .dev_attrs      = NULL,
 143         .match          = intel_th_match,
 144         .probe          = intel_th_probe,
 145         .remove         = intel_th_remove,
 146 };
 147
 148 static void intel_th_device_free(struct intel_th_device *thdev);
 149
 150 static void intel_th_device_release(struct device *dev)
 151 {
 152         intel_th_device_free(to_intel_th_device(dev));
 153 }
 154
 155 static struct device_type intel_th_source_device_type = {
 156         .name           = "intel_th_source_device",
 157         .release        = intel_th_device_release,
 158 };
 159
 160 static struct intel_th *to_intel_th(struct intel_th_device *thdev)
 161 {
 162         /*
 163          * subdevice tree is flat: if this one is not a switch, its
 164          * parent must be
 165          */
 166         if (thdev->type != INTEL_TH_SWITCH)
 167                 thdev = to_intel_th_hub(thdev);
 168
 169         if (WARN_ON_ONCE(!thdev || thdev->type != INTEL_TH_SWITCH))
 170                 return NULL;
 171
 172         return dev_get_drvdata(thdev->dev.parent);
 173 }
 174
 175 static char *intel_th_output_devnode(struct device *dev, umode_t *mode,
 176                                      kuid_t *uid, kgid_t *gid)
 177 {
 178         struct intel_th_device *thdev = to_intel_th_device(dev);
 179         struct intel_th *th = to_intel_th(thdev);
 180         char *node;
 181
 182         if (thdev->id >= 0)
 183                 node = kasprintf(GFP_KERNEL, "intel_th%d/%s%d", th->id,
 184                                  thdev->name, thdev->id);
 185         else
 186                 node = kasprintf(GFP_KERNEL, "intel_th%d/%s", th->id,
 187                                  thdev->name);
 188
 189         return node;
 190 }
 191
 192 static ssize_t port_show(struct device *dev, struct device_attribute *attr,
 193                          char *buf)
 194 {
 195         struct intel_th_device *thdev = to_intel_th_device(dev);
 196
 197         if (thdev->output.port >= 0)
 198                 return scnprintf(buf, PAGE_SIZE, "%u\n", thdev->output.port);
 199
 200         return scnprintf(buf, PAGE_SIZE, "unassigned\n");
 201 }
 202
 203 static DEVICE_ATTR_RO(port);
 204
 205 static int intel_th_output_activate(struct intel_th_device *thdev)
 206 {
 207         struct intel_th_driver *thdrv =
 208                 to_intel_th_driver_or_null(thdev->dev.driver);
 209         int ret = 0;
 210
 211         if (!thdrv)
 212                 return -ENODEV;
 213
 214         if (!try_module_get(thdrv->driver.owner))
 215                 return -ENODEV;
 216
 217         pm_runtime_get_sync(&thdev->dev);
 218
 219         if (thdrv->activate)
 220                 ret = thdrv->activate(thdev);
 221         else
 222                 intel_th_trace_enable(thdev);
 223
 224         if (ret)
 225                 pm_runtime_put(&thdev->dev);
 226
 227         return ret;
 228 }
 229
 230 static void intel_th_output_deactivate(struct intel_th_device *thdev)
 231 {
 232         struct intel_th_driver *thdrv =
 233                 to_intel_th_driver_or_null(thdev->dev.driver);
 234
 235         if (!thdrv)
 236                 return;
 237
 238         if (thdrv->deactivate)
 239                 thdrv->deactivate(thdev);
 240         else
 241                 intel_th_trace_disable(thdev);
 242
 243         pm_runtime_put(&thdev->dev);
 244         module_put(thdrv->driver.owner);
 245 }
 246
 247 static ssize_t active_show(struct device *dev, struct device_attribute *attr,
 248                            char *buf)
 249 {
 250         struct intel_th_device *thdev = to_intel_th_device(dev);
 251
 252         return scnprintf(buf, PAGE_SIZE, "%d\n", thdev->output.active);
 253 }
 254
 255 static ssize_t active_store(struct device *dev, struct device_attribute *attr,
 256                             const char *buf, size_t size)
 257 {
 258         struct intel_th_device *thdev = to_intel_th_device(dev);
 259         unsigned long val;
 260         int ret;
 261
 262         ret = kstrtoul(buf, 10, &val);
 263         if (ret)
 264                 return ret;
 265
 266         if (!!val != thdev->output.active) {
 267                 if (val)
 268                         ret = intel_th_output_activate(thdev);
 269                 else
 270                         intel_th_output_deactivate(thdev);
 271         }
 272
 273         return ret ? ret : size;
 274 }
 275
 276 static DEVICE_ATTR_RW(active);
 277
 278 static struct attribute *intel_th_output_attrs[] = {
 279         &dev_attr_port.attr,
 280         &dev_attr_active.attr,
 281         NULL,
 282 };
 283
 284 ATTRIBUTE_GROUPS(intel_th_output);
 285
 286 static struct device_type intel_th_output_device_type = {
 287         .name           = "intel_th_output_device",
 288         .groups         = intel_th_output_groups,
 289         .release        = intel_th_device_release,
 290         .devnode        = intel_th_output_devnode,
 291 };
 292
 293 static struct device_type intel_th_switch_device_type = {
 294         .name           = "intel_th_switch_device",
 295         .release        = intel_th_device_release,
 296 };
 297
 298 static struct device_type *intel_th_device_type[] = {
 299         [INTEL_TH_SOURCE]       = &intel_th_source_device_type,
 300         [INTEL_TH_OUTPUT]       = &intel_th_output_device_type,
 301         [INTEL_TH_SWITCH]       = &intel_th_switch_device_type,
 302 };
 303
 304 int intel_th_driver_register(struct intel_th_driver *thdrv)
 305 {
 306         if (!thdrv->probe || !thdrv->remove)
 307                 return -EINVAL;
 308
 309         thdrv->driver.bus = &intel_th_bus;
 310
 311         return driver_register(&thdrv->driver);
 312 }
 313 EXPORT_SYMBOL_GPL(intel_th_driver_register);
 314
 315 void intel_th_driver_unregister(struct intel_th_driver *thdrv)
 316 {
 317         driver_unregister(&thdrv->driver);
 318 }
 319 EXPORT_SYMBOL_GPL(intel_th_driver_unregister);
 320
 321 static struct intel_th_device *
 322 intel_th_device_alloc(struct intel_th *th, unsigned int type, const char *name,
 323                       int id)
 324 {
 325         struct device *parent;
 326         struct intel_th_device *thdev;
 327
 328         if (type == INTEL_TH_SWITCH)
 329                 parent = th->dev;
 330         else
 331                 parent = &th->hub->dev;
 332
 333         thdev = kzalloc(sizeof(*thdev) + strlen(name) + 1, GFP_KERNEL);
 334         if (!thdev)
 335                 return NULL;
 336
 337         thdev->id = id;
 338         thdev->type = type;
 339
 340         strcpy(thdev->name, name);
 341         device_initialize(&thdev->dev);
 342         thdev->dev.bus = &intel_th_bus;
 343         thdev->dev.type = intel_th_device_type[type];
 344         thdev->dev.parent = parent;
 345         thdev->dev.dma_mask = parent->dma_mask;
 346         thdev->dev.dma_parms = parent->dma_parms;
 347         dma_set_coherent_mask(&thdev->dev, parent->coherent_dma_mask);
 348         if (id >= 0)
 349                 dev_set_name(&thdev->dev, "%d-%s%d", th->id, name, id);
 350         else
 351                 dev_set_name(&thdev->dev, "%d-%s", th->id, name);
 352
 353         return thdev;
 354 }
 355
 356 static int intel_th_device_add_resources(struct intel_th_device *thdev,
 357                                          struct resource *res, int nres)
 358 {
 359         struct resource *r;
 360
 361         r = kmemdup(res, sizeof(*res) * nres, GFP_KERNEL);
 362         if (!r)
 363                 return -ENOMEM;
 364
 365         thdev->resource = r;
 366         thdev->num_resources = nres;
 367
 368         return 0;
 369 }
 370
 371 static void intel_th_device_remove(struct intel_th_device *thdev)
 372 {
 373         device_del(&thdev->dev);
 374         put_device(&thdev->dev);
 375 }
 376
 377 static void intel_th_device_free(struct intel_th_device *thdev)
 378 {
 379         kfree(thdev->resource);
 380         kfree(thdev);
 381 }
 382
 383 /*
 384  * Intel(R) Trace Hub subdevices
 385  */
 386 static const struct intel_th_subdevice {
 387         const char              *name;
 388         struct resource         res[3];
 389         unsigned                nres;
 390         unsigned                type;
 391         unsigned                otype;
 392         unsigned                scrpd;
 393         int                     id;
 394 } intel_th_subdevices[TH_SUBDEVICE_MAX] = {
 395         {
 396                 .nres   = 1,
 397                 .res    = {
 398                         {
 399                                 .start  = REG_GTH_OFFSET,
 400                                 .end    = REG_GTH_OFFSET + REG_GTH_LENGTH - 1,
 401                                 .flags  = IORESOURCE_MEM,
 402                         },
 403                 },
 404                 .name   = "gth",
 405                 .type   = INTEL_TH_SWITCH,
 406                 .id     = -1,
 407         },
 408         {
 409                 .nres   = 2,
 410                 .res    = {
 411                         {
 412                                 .start  = REG_MSU_OFFSET,
 413                                 .end    = REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
 414                                 .flags  = IORESOURCE_MEM,
 415                         },
 416                         {
 417                                 .start  = BUF_MSU_OFFSET,
 418                                 .end    = BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
 419                                 .flags  = IORESOURCE_MEM,
 420                         },
 421                 },
 422                 .name   = "msc",
 423                 .id     = 0,
 424                 .type   = INTEL_TH_OUTPUT,
 425                 .otype  = GTH_MSU,
 426                 .scrpd  = SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC0_IS_ENABLED,
 427         },
 428         {
 429                 .nres   = 2,
 430                 .res    = {
 431                         {
 432                                 .start  = REG_MSU_OFFSET,
 433                                 .end    = REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
 434                                 .flags  = IORESOURCE_MEM,
 435                         },
 436                         {
 437                                 .start  = BUF_MSU_OFFSET,
 438                                 .end    = BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
 439                                 .flags  = IORESOURCE_MEM,
 440                         },
 441                 },
 442                 .name   = "msc",
 443                 .id     = 1,
 444                 .type   = INTEL_TH_OUTPUT,
 445                 .otype  = GTH_MSU,
 446                 .scrpd  = SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC1_IS_ENABLED,
 447         },
 448         {
 449                 .nres   = 2,
 450                 .res    = {
 451                         {
 452                                 .start  = REG_STH_OFFSET,
 453                                 .end    = REG_STH_OFFSET + REG_STH_LENGTH - 1,
 454                                 .flags  = IORESOURCE_MEM,
 455                         },
 456                         {
 457                                 .start  = TH_MMIO_SW,
 458                                 .end    = 0,
 459                                 .flags  = IORESOURCE_MEM,
 460                         },
 461                 },
 462                 .id     = -1,
 463                 .name   = "sth",
 464                 .type   = INTEL_TH_SOURCE,
 465         },
 466         {
 467                 .nres   = 1,
 468                 .res    = {
 469                         {
 470                                 .start  = REG_PTI_OFFSET,
 471                                 .end    = REG_PTI_OFFSET + REG_PTI_LENGTH - 1,
 472                                 .flags  = IORESOURCE_MEM,
 473                         },
 474                 },
 475                 .id     = -1,
 476                 .name   = "pti",
 477                 .type   = INTEL_TH_OUTPUT,
 478                 .otype  = GTH_PTI,
 479                 .scrpd  = SCRPD_PTI_IS_PRIM_DEST,
 480         },
 481         {
 482                 .nres   = 1,
 483                 .res    = {
 484                         {
 485                                 .start  = REG_DCIH_OFFSET,
 486                                 .end    = REG_DCIH_OFFSET + REG_DCIH_LENGTH - 1,
 487                                 .flags  = IORESOURCE_MEM,
 488                         },
 489                 },
 490                 .id     = -1,
 491                 .name   = "dcih",
 492                 .type   = INTEL_TH_OUTPUT,
 493         },
 494 };
 495
 496 #ifdef CONFIG_MODULES
 497 static void __intel_th_request_hub_module(struct work_struct *work)
 498 {
 499         struct intel_th *th = container_of(work, struct intel_th,
 500                                            request_module_work);
 501
 502         request_module("intel_th_%s", th->hub->name);
 503 }
 504
 505 static int intel_th_request_hub_module(struct intel_th *th)
 506 {
 507         INIT_WORK(&th->request_module_work, __intel_th_request_hub_module);
 508         schedule_work(&th->request_module_work);
 509
 510         return 0;
 511 }
 512
 513 static void intel_th_request_hub_module_flush(struct intel_th *th)
 514 {
 515         flush_work(&th->request_module_work);
 516 }
 517 #else
 518 static inline int intel_th_request_hub_module(struct intel_th *th)
 519 {
 520         return -EINVAL;
 521 }
 522
 523 static inline void intel_th_request_hub_module_flush(struct intel_th *th)
 524 {
 525 }
 526 #endif /* CONFIG_MODULES */
 527
 528 static int intel_th_populate(struct intel_th *th, struct resource *devres,
 529                              unsigned int ndevres, int irq)
 530 {
 531         struct resource res[3];
 532         unsigned int req = 0;
 533         int src, dst, err;
 534
 535         /* create devices for each intel_th_subdevice */
 536         for (src = 0, dst = 0; src < ARRAY_SIZE(intel_th_subdevices); src++) {
 537                 const struct intel_th_subdevice *subdev =
 538                         &intel_th_subdevices[src];
 539                 struct intel_th_device *thdev;
 540                 int r;
 541
 542                 /* only allow SOURCE and SWITCH devices in host mode */
 543                 if (host_mode && subdev->type == INTEL_TH_OUTPUT)
 544                         continue;
 545
 546                 thdev = intel_th_device_alloc(th, subdev->type, subdev->name,
 547                                               subdev->id);
 548                 if (!thdev) {
 549                         err = -ENOMEM;
 550                         goto kill_subdevs;
 551                 }
 552
 553                 memcpy(res, subdev->res,
 554                        sizeof(struct resource) * subdev->nres);
 555
 556                 for (r = 0; r < subdev->nres; r++) {
 557                         int bar = TH_MMIO_CONFIG;
 558
 559                         /*
 560                          * Take .end == 0 to mean 'take the whole bar',
 561                          * .start then tells us which bar it is. Default to
 562                          * TH_MMIO_CONFIG.
 563                          */
 564                         if (!res[r].end && res[r].flags == IORESOURCE_MEM) {
 565                                 bar = res[r].start;
 566                                 res[r].start = 0;
 567                                 res[r].end = resource_size(&devres[bar]) - 1;
 568                         }
 569
 570                         if (res[r].flags & IORESOURCE_MEM) {
 571                                 res[r].start    += devres[bar].start;
 572                                 res[r].end      += devres[bar].start;
 573
 574                                 dev_dbg(th->dev, "%s:%d @ %pR\n",
 575                                         subdev->name, r, &res[r]);
 576                         } else if (res[r].flags & IORESOURCE_IRQ) {
 577                                 res[r].start    = irq;
 578                         }
 579                 }
 580
 581                 err = intel_th_device_add_resources(thdev, res, subdev->nres);
 582                 if (err) {
 583                         put_device(&thdev->dev);
 584                         goto kill_subdevs;
 585                 }
 586
 587                 if (subdev->type == INTEL_TH_OUTPUT) {
 588                         thdev->dev.devt = MKDEV(th->major, dst);
 589                         thdev->output.type = subdev->otype;
 590                         thdev->output.port = -1;
 591                         thdev->output.scratchpad = subdev->scrpd;
 592                 } else if (subdev->type == INTEL_TH_SWITCH) {
 593                         thdev->host_mode = host_mode;
 594                 }
 595
 596                 err = device_add(&thdev->dev);
 597                 if (err) {
 598                         put_device(&thdev->dev);
 599                         goto kill_subdevs;
 600                 }
 601
 602                 /* need switch driver to be loaded to enumerate the rest */
 603                 if (subdev->type == INTEL_TH_SWITCH && !req) {
 604                         th->hub = thdev;
 605                         err = intel_th_request_hub_module(th);
 606                         if (!err)
 607                                 req++;
 608                 }
 609
 610                 th->thdev[dst++] = thdev;
 611         }
 612
 613         return 0;
 614
 615 kill_subdevs:
 616         for (; dst >= 0; dst--)
 617                 intel_th_device_remove(th->thdev[dst]);
 618
 619         return err;
 620 }
 621
 622 static int match_devt(struct device *dev, void *data)
 623 {
 624         dev_t devt = (dev_t)(unsigned long)data;
 625
 626         return dev->devt == devt;
 627 }
 628
 629 static int intel_th_output_open(struct inode *inode, struct file *file)
 630 {
 631         const struct file_operations *fops;
 632         struct intel_th_driver *thdrv;
 633         struct device *dev;
 634         int err;
 635
 636         dev = bus_find_device(&intel_th_bus, NULL,
 637                               (void *)(unsigned long)inode->i_rdev,
 638                               match_devt);
 639         if (!dev || !dev->driver)
 640                 return -ENODEV;
 641
 642         thdrv = to_intel_th_driver(dev->driver);
 643         fops = fops_get(thdrv->fops);
 644         if (!fops)
 645                 return -ENODEV;
 646
 647         replace_fops(file, fops);
 648
 649         file->private_data = to_intel_th_device(dev);
 650
 651         if (file->f_op->open) {
 652                 err = file->f_op->open(inode, file);
 653                 return err;
 654         }
 655
 656         return 0;
 657 }
 658
 659 static const struct file_operations intel_th_output_fops = {
 660         .open   = intel_th_output_open,
 661         .llseek = noop_llseek,
 662 };
 663
 664 /**
 665  * intel_th_alloc() - allocate a new Intel TH device and its subdevices
 666  * @dev:        parent device
 667  * @devres:     parent's resources
 668  * @ndevres:    number of resources
 669  * @irq:        irq number
 670  */
 671 struct intel_th *
 672 intel_th_alloc(struct device *dev, struct resource *devres,
 673                unsigned int ndevres, int irq)
 674 {
 675         struct intel_th *th;
 676         int err;
 677
 678         th = kzalloc(sizeof(*th), GFP_KERNEL);
 679         if (!th)
 680                 return ERR_PTR(-ENOMEM);
 681
 682         th->id = ida_simple_get(&intel_th_ida, 0, 0, GFP_KERNEL);
 683         if (th->id < 0) {
 684                 err = th->id;
 685                 goto err_alloc;
 686         }
 687
 688         th->major = __register_chrdev(0, 0, TH_POSSIBLE_OUTPUTS,
 689                                       "intel_th/output", &intel_th_output_fops);
 690         if (th->major < 0) {
 691                 err = th->major;
 692                 goto err_ida;
 693         }
 694         th->dev = dev;
 695
 696         dev_set_drvdata(dev, th);
 697
 698         pm_runtime_no_callbacks(dev);
 699         pm_runtime_put(dev);
 700         pm_runtime_allow(dev);
 701
 702         err = intel_th_populate(th, devres, ndevres, irq);
 703         if (err)
 704                 goto err_chrdev;
 705
 706         return th;
 707
 708 err_chrdev:
 709         pm_runtime_forbid(dev);
 710
 711         __unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
 712                             "intel_th/output");
 713
 714 err_ida:
 715         ida_simple_remove(&intel_th_ida, th->id);
 716
 717 err_alloc:
 718         kfree(th);
 719
 720         return ERR_PTR(err);
 721 }
 722 EXPORT_SYMBOL_GPL(intel_th_alloc);
 723
 724 void intel_th_free(struct intel_th *th)
 725 {
 726         int i;
 727
 728         intel_th_request_hub_module_flush(th);
 729         for (i = 0; i < TH_SUBDEVICE_MAX; i++)
 730                 if (th->thdev[i] && th->thdev[i] != th->hub)
 731                         intel_th_device_remove(th->thdev[i]);
 732
 733         intel_th_device_remove(th->hub);
 734
 735         pm_runtime_get_sync(th->dev);
 736         pm_runtime_forbid(th->dev);
 737
 738         __unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
 739                             "intel_th/output");
 740
 741         ida_simple_remove(&intel_th_ida, th->id);
 742
 743         kfree(th);
 744 }
 745 EXPORT_SYMBOL_GPL(intel_th_free);
 746
 747 /**
 748  * intel_th_trace_enable() - enable tracing for an output device
 749  * @thdev:      output device that requests tracing be enabled
 750  */
 751 int intel_th_trace_enable(struct intel_th_device *thdev)
 752 {
 753         struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
 754         struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 755
 756         if (WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH))
 757                 return -EINVAL;
 758
 759         if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
 760                 return -EINVAL;
 761
 762         pm_runtime_get_sync(&thdev->dev);
 763         hubdrv->enable(hub, &thdev->output);
 764
 765         return 0;
 766 }
 767 EXPORT_SYMBOL_GPL(intel_th_trace_enable);
 768
 769 /**
 770  * intel_th_trace_disable() - disable tracing for an output device
 771  * @thdev:      output device that requests tracing be disabled
 772  */
 773 int intel_th_trace_disable(struct intel_th_device *thdev)
 774 {
 775         struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
 776         struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 777
 778         WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH);
 779         if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
 780                 return -EINVAL;
 781
 782         hubdrv->disable(hub, &thdev->output);
 783         pm_runtime_put(&thdev->dev);
 784
 785         return 0;
 786 }
 787 EXPORT_SYMBOL_GPL(intel_th_trace_disable);
 788
 789 int intel_th_set_output(struct intel_th_device *thdev,
 790                         unsigned int master)
 791 {
 792         struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
 793         struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 794
 795         if (!hubdrv->set_output)
 796                 return -ENOTSUPP;
 797
 798         return hubdrv->set_output(hub, master);
 799 }
 800 EXPORT_SYMBOL_GPL(intel_th_set_output);
 801
 802 static int __init intel_th_init(void)
 803 {
 804         intel_th_debug_init();
 805
 806         return bus_register(&intel_th_bus);
 807 }
 808 subsys_initcall(intel_th_init);
 809
 810 static void __exit intel_th_exit(void)
 811 {
 812         intel_th_debug_done();
 813
 814         bus_unregister(&intel_th_bus);
 815 }
 816 module_exit(intel_th_exit);
 817
 818 MODULE_LICENSE("GPL v2");
 819 MODULE_DESCRIPTION("Intel(R) Trace Hub controller driver");
 820 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");