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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Intel(R) Trace Hub driver core
   4 *
   5 * Copyright (C) 2014-2015 Intel Corporation.
   6 */
   7
   8#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
   9
  10#include <linux/types.h>
  11#include <linux/module.h>
  12#include <linux/device.h>
  13#include <linux/sysfs.h>
  14#include <linux/kdev_t.h>
  15#include <linux/debugfs.h>
  16#include <linux/idr.h>
  17#include <linux/pci.h>
  18#include <linux/pm_runtime.h>
  19#include <linux/dma-mapping.h>
  20
  21#include "intel_th.h"
  22#include "debug.h"
  23
  24static bool host_mode __read_mostly;
  25module_param(host_mode, bool, 0444);
  26
  27static DEFINE_IDA(intel_th_ida);
  28
  29static int intel_th_match(struct device *dev, const struct device_driver *driver)
  30{
  31	const struct intel_th_driver *thdrv = to_intel_th_driver(driver);
  32	struct intel_th_device *thdev = to_intel_th_device(dev);
  33
  34	if (thdev->type == INTEL_TH_SWITCH &&
  35	    (!thdrv->enable || !thdrv->disable))
  36		return 0;
  37
  38	return !strcmp(thdev->name, driver->name);
  39}
  40
  41static int intel_th_child_remove(struct device *dev, void *data)
  42{
  43	device_release_driver(dev);
  44
  45	return 0;
  46}
  47
  48static int intel_th_probe(struct device *dev)
  49{
  50	struct intel_th_driver *thdrv = to_intel_th_driver(dev->driver);
  51	struct intel_th_device *thdev = to_intel_th_device(dev);
  52	struct intel_th_driver *hubdrv;
  53	struct intel_th_device *hub = NULL;
  54	int ret;
  55
  56	if (thdev->type == INTEL_TH_SWITCH)
  57		hub = thdev;
  58	else if (dev->parent)
  59		hub = to_intel_th_device(dev->parent);
  60
  61	if (!hub || !hub->dev.driver)
  62		return -EPROBE_DEFER;
  63
  64	hubdrv = to_intel_th_driver(hub->dev.driver);
  65
  66	pm_runtime_set_active(dev);
  67	pm_runtime_no_callbacks(dev);
  68	pm_runtime_enable(dev);
  69
  70	ret = thdrv->probe(to_intel_th_device(dev));
  71	if (ret)
  72		goto out_pm;
  73
  74	if (thdrv->attr_group) {
  75		ret = sysfs_create_group(&thdev->dev.kobj, thdrv->attr_group);
  76		if (ret)
  77			goto out;
  78	}
  79
  80	if (thdev->type == INTEL_TH_OUTPUT &&
  81	    !intel_th_output_assigned(thdev))
  82		/* does not talk to hardware */
  83		ret = hubdrv->assign(hub, thdev);
  84
  85out:
  86	if (ret)
  87		thdrv->remove(thdev);
  88
  89out_pm:
  90	if (ret)
  91		pm_runtime_disable(dev);
  92
  93	return ret;
  94}
  95
  96static void intel_th_device_remove(struct intel_th_device *thdev);
  97
  98static void intel_th_remove(struct device *dev)
  99{
 100	struct intel_th_driver *thdrv = to_intel_th_driver(dev->driver);
 101	struct intel_th_device *thdev = to_intel_th_device(dev);
 102	struct intel_th_device *hub = to_intel_th_hub(thdev);
 103
 104	if (thdev->type == INTEL_TH_SWITCH) {
 105		struct intel_th *th = to_intel_th(hub);
 106		int i, lowest;
 107
 108		/*
 109		 * disconnect outputs
 110		 *
 111		 * intel_th_child_remove returns 0 unconditionally, so there is
 112		 * no need to check the return value of device_for_each_child.
 113		 */
 114		device_for_each_child(dev, thdev, intel_th_child_remove);
 115
 116		/*
 117		 * Remove outputs, that is, hub's children: they are created
 118		 * at hub's probe time by having the hub call
 119		 * intel_th_output_enable() for each of them.
 120		 */
 121		for (i = 0, lowest = -1; i < th->num_thdevs; i++) {
 122			/*
 123			 * Move the non-output devices from higher up the
 124			 * th->thdev[] array to lower positions to maintain
 125			 * a contiguous array.
 126			 */
 127			if (th->thdev[i]->type != INTEL_TH_OUTPUT) {
 128				if (lowest >= 0) {
 129					th->thdev[lowest] = th->thdev[i];
 130					th->thdev[i] = NULL;
 131					++lowest;
 132				}
 133
 134				continue;
 135			}
 136
 137			if (lowest == -1)
 138				lowest = i;
 139
 140			intel_th_device_remove(th->thdev[i]);
 141			th->thdev[i] = NULL;
 142		}
 143
 144		if (lowest >= 0)
 145			th->num_thdevs = lowest;
 146	}
 147
 148	if (thdrv->attr_group)
 149		sysfs_remove_group(&thdev->dev.kobj, thdrv->attr_group);
 150
 151	pm_runtime_get_sync(dev);
 152
 153	thdrv->remove(thdev);
 154
 155	if (intel_th_output_assigned(thdev)) {
 156		struct intel_th_driver *hubdrv =
 157			to_intel_th_driver(dev->parent->driver);
 158
 159		if (hub->dev.driver)
 160			/* does not talk to hardware */
 161			hubdrv->unassign(hub, thdev);
 162	}
 163
 164	pm_runtime_disable(dev);
 165	pm_runtime_set_active(dev);
 166	pm_runtime_enable(dev);
 167}
 168
 169static struct bus_type intel_th_bus = {
 170	.name		= "intel_th",
 171	.match		= intel_th_match,
 172	.probe		= intel_th_probe,
 173	.remove		= intel_th_remove,
 174};
 175
 176static void intel_th_device_free(struct intel_th_device *thdev);
 177
 178static void intel_th_device_release(struct device *dev)
 179{
 180	intel_th_device_free(to_intel_th_device(dev));
 181}
 182
 183static const struct device_type intel_th_source_device_type = {
 184	.name		= "intel_th_source_device",
 185	.release	= intel_th_device_release,
 186};
 187
 188static char *intel_th_output_devnode(const struct device *dev, umode_t *mode,
 189				     kuid_t *uid, kgid_t *gid)
 190{
 191	const struct intel_th_device *thdev = to_intel_th_device(dev);
 192	const struct intel_th *th = to_intel_th(thdev);
 193	char *node;
 194
 195	if (thdev->id >= 0)
 196		node = kasprintf(GFP_KERNEL, "intel_th%d/%s%d", th->id,
 197				 thdev->name, thdev->id);
 198	else
 199		node = kasprintf(GFP_KERNEL, "intel_th%d/%s", th->id,
 200				 thdev->name);
 201
 202	return node;
 203}
 204
 205static ssize_t port_show(struct device *dev, struct device_attribute *attr,
 206			 char *buf)
 207{
 208	struct intel_th_device *thdev = to_intel_th_device(dev);
 209
 210	if (thdev->output.port >= 0)
 211		return scnprintf(buf, PAGE_SIZE, "%u\n", thdev->output.port);
 212
 213	return scnprintf(buf, PAGE_SIZE, "unassigned\n");
 214}
 215
 216static DEVICE_ATTR_RO(port);
 217
 218static void intel_th_trace_prepare(struct intel_th_device *thdev)
 219{
 220	struct intel_th_device *hub = to_intel_th_hub(thdev);
 221	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 222
 223	if (hub->type != INTEL_TH_SWITCH)
 224		return;
 225
 226	if (thdev->type != INTEL_TH_OUTPUT)
 227		return;
 228
 229	pm_runtime_get_sync(&thdev->dev);
 230	hubdrv->prepare(hub, &thdev->output);
 231	pm_runtime_put(&thdev->dev);
 232}
 233
 234static int intel_th_output_activate(struct intel_th_device *thdev)
 235{
 236	struct intel_th_driver *thdrv =
 237		to_intel_th_driver_or_null(thdev->dev.driver);
 238	struct intel_th *th = to_intel_th(thdev);
 239	int ret = 0;
 240
 241	if (!thdrv)
 242		return -ENODEV;
 243
 244	if (!try_module_get(thdrv->driver.owner))
 245		return -ENODEV;
 246
 247	pm_runtime_get_sync(&thdev->dev);
 248
 249	if (th->activate)
 250		ret = th->activate(th);
 251	if (ret)
 252		goto fail_put;
 253
 254	intel_th_trace_prepare(thdev);
 255	if (thdrv->activate)
 256		ret = thdrv->activate(thdev);
 257	else
 258		intel_th_trace_enable(thdev);
 259
 260	if (ret)
 261		goto fail_deactivate;
 262
 263	return 0;
 264
 265fail_deactivate:
 266	if (th->deactivate)
 267		th->deactivate(th);
 268
 269fail_put:
 270	pm_runtime_put(&thdev->dev);
 271	module_put(thdrv->driver.owner);
 272
 273	return ret;
 274}
 275
 276static void intel_th_output_deactivate(struct intel_th_device *thdev)
 277{
 278	struct intel_th_driver *thdrv =
 279		to_intel_th_driver_or_null(thdev->dev.driver);
 280	struct intel_th *th = to_intel_th(thdev);
 281
 282	if (!thdrv)
 283		return;
 284
 285	if (thdrv->deactivate)
 286		thdrv->deactivate(thdev);
 287	else
 288		intel_th_trace_disable(thdev);
 289
 290	if (th->deactivate)
 291		th->deactivate(th);
 292
 293	pm_runtime_put(&thdev->dev);
 294	module_put(thdrv->driver.owner);
 295}
 296
 297static ssize_t active_show(struct device *dev, struct device_attribute *attr,
 298			   char *buf)
 299{
 300	struct intel_th_device *thdev = to_intel_th_device(dev);
 301
 302	return scnprintf(buf, PAGE_SIZE, "%d\n", thdev->output.active);
 303}
 304
 305static ssize_t active_store(struct device *dev, struct device_attribute *attr,
 306			    const char *buf, size_t size)
 307{
 308	struct intel_th_device *thdev = to_intel_th_device(dev);
 309	unsigned long val;
 310	int ret;
 311
 312	ret = kstrtoul(buf, 10, &val);
 313	if (ret)
 314		return ret;
 315
 316	if (!!val != thdev->output.active) {
 317		if (val)
 318			ret = intel_th_output_activate(thdev);
 319		else
 320			intel_th_output_deactivate(thdev);
 321	}
 322
 323	return ret ? ret : size;
 324}
 325
 326static DEVICE_ATTR_RW(active);
 327
 328static struct attribute *intel_th_output_attrs[] = {
 329	&dev_attr_port.attr,
 330	&dev_attr_active.attr,
 331	NULL,
 332};
 333
 334ATTRIBUTE_GROUPS(intel_th_output);
 335
 336static const struct device_type intel_th_output_device_type = {
 337	.name		= "intel_th_output_device",
 338	.groups		= intel_th_output_groups,
 339	.release	= intel_th_device_release,
 340	.devnode	= intel_th_output_devnode,
 341};
 342
 343static const struct device_type intel_th_switch_device_type = {
 344	.name		= "intel_th_switch_device",
 345	.release	= intel_th_device_release,
 346};
 347
 348static const struct device_type *intel_th_device_type[] = {
 349	[INTEL_TH_SOURCE]	= &intel_th_source_device_type,
 350	[INTEL_TH_OUTPUT]	= &intel_th_output_device_type,
 351	[INTEL_TH_SWITCH]	= &intel_th_switch_device_type,
 352};
 353
 354int intel_th_driver_register(struct intel_th_driver *thdrv)
 355{
 356	if (!thdrv->probe || !thdrv->remove)
 357		return -EINVAL;
 358
 359	thdrv->driver.bus = &intel_th_bus;
 360
 361	return driver_register(&thdrv->driver);
 362}
 363EXPORT_SYMBOL_GPL(intel_th_driver_register);
 364
 365void intel_th_driver_unregister(struct intel_th_driver *thdrv)
 366{
 367	driver_unregister(&thdrv->driver);
 368}
 369EXPORT_SYMBOL_GPL(intel_th_driver_unregister);
 370
 371static struct intel_th_device *
 372intel_th_device_alloc(struct intel_th *th, unsigned int type, const char *name,
 373		      int id)
 374{
 375	struct device *parent;
 376	struct intel_th_device *thdev;
 377
 378	if (type == INTEL_TH_OUTPUT)
 379		parent = &th->hub->dev;
 380	else
 381		parent = th->dev;
 382
 383	thdev = kzalloc(sizeof(*thdev) + strlen(name) + 1, GFP_KERNEL);
 384	if (!thdev)
 385		return NULL;
 386
 387	thdev->id = id;
 388	thdev->type = type;
 389
 390	strcpy(thdev->name, name);
 391	device_initialize(&thdev->dev);
 392	thdev->dev.bus = &intel_th_bus;
 393	thdev->dev.type = intel_th_device_type[type];
 394	thdev->dev.parent = parent;
 395	thdev->dev.dma_mask = parent->dma_mask;
 396	thdev->dev.dma_parms = parent->dma_parms;
 397	dma_set_coherent_mask(&thdev->dev, parent->coherent_dma_mask);
 398	if (id >= 0)
 399		dev_set_name(&thdev->dev, "%d-%s%d", th->id, name, id);
 400	else
 401		dev_set_name(&thdev->dev, "%d-%s", th->id, name);
 402
 403	return thdev;
 404}
 405
 406static int intel_th_device_add_resources(struct intel_th_device *thdev,
 407					 struct resource *res, int nres)
 408{
 409	struct resource *r;
 410
 411	r = kmemdup(res, sizeof(*res) * nres, GFP_KERNEL);
 412	if (!r)
 413		return -ENOMEM;
 414
 415	thdev->resource = r;
 416	thdev->num_resources = nres;
 417
 418	return 0;
 419}
 420
 421static void intel_th_device_remove(struct intel_th_device *thdev)
 422{
 423	device_del(&thdev->dev);
 424	put_device(&thdev->dev);
 425}
 426
 427static void intel_th_device_free(struct intel_th_device *thdev)
 428{
 429	kfree(thdev->resource);
 430	kfree(thdev);
 431}
 432
 433/*
 434 * Intel(R) Trace Hub subdevices
 435 */
 436static const struct intel_th_subdevice {
 437	const char		*name;
 438	struct resource		res[3];
 439	unsigned		nres;
 440	unsigned		type;
 441	unsigned		otype;
 442	bool			mknode;
 443	unsigned		scrpd;
 444	int			id;
 445} intel_th_subdevices[] = {
 446	{
 447		.nres	= 1,
 448		.res	= {
 449			{
 450				/* Handle TSCU and CTS from GTH driver */
 451				.start	= REG_GTH_OFFSET,
 452				.end	= REG_CTS_OFFSET + REG_CTS_LENGTH - 1,
 453				.flags	= IORESOURCE_MEM,
 454			},
 455		},
 456		.name	= "gth",
 457		.type	= INTEL_TH_SWITCH,
 458		.id	= -1,
 459	},
 460	{
 461		.nres	= 2,
 462		.res	= {
 463			{
 464				.start	= REG_MSU_OFFSET,
 465				.end	= REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
 466				.flags	= IORESOURCE_MEM,
 467			},
 468			{
 469				.start	= BUF_MSU_OFFSET,
 470				.end	= BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
 471				.flags	= IORESOURCE_MEM,
 472			},
 473		},
 474		.name	= "msc",
 475		.id	= 0,
 476		.type	= INTEL_TH_OUTPUT,
 477		.mknode	= true,
 478		.otype	= GTH_MSU,
 479		.scrpd	= SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC0_IS_ENABLED,
 480	},
 481	{
 482		.nres	= 2,
 483		.res	= {
 484			{
 485				.start	= REG_MSU_OFFSET,
 486				.end	= REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
 487				.flags	= IORESOURCE_MEM,
 488			},
 489			{
 490				.start	= BUF_MSU_OFFSET,
 491				.end	= BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
 492				.flags	= IORESOURCE_MEM,
 493			},
 494		},
 495		.name	= "msc",
 496		.id	= 1,
 497		.type	= INTEL_TH_OUTPUT,
 498		.mknode	= true,
 499		.otype	= GTH_MSU,
 500		.scrpd	= SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC1_IS_ENABLED,
 501	},
 502	{
 503		.nres	= 2,
 504		.res	= {
 505			{
 506				.start	= REG_STH_OFFSET,
 507				.end	= REG_STH_OFFSET + REG_STH_LENGTH - 1,
 508				.flags	= IORESOURCE_MEM,
 509			},
 510			{
 511				.start	= TH_MMIO_SW,
 512				.end	= 0,
 513				.flags	= IORESOURCE_MEM,
 514			},
 515		},
 516		.id	= -1,
 517		.name	= "sth",
 518		.type	= INTEL_TH_SOURCE,
 519	},
 520	{
 521		.nres	= 2,
 522		.res	= {
 523			{
 524				.start	= REG_STH_OFFSET,
 525				.end	= REG_STH_OFFSET + REG_STH_LENGTH - 1,
 526				.flags	= IORESOURCE_MEM,
 527			},
 528			{
 529				.start	= TH_MMIO_RTIT,
 530				.end	= 0,
 531				.flags	= IORESOURCE_MEM,
 532			},
 533		},
 534		.id	= -1,
 535		.name	= "rtit",
 536		.type	= INTEL_TH_SOURCE,
 537	},
 538	{
 539		.nres	= 1,
 540		.res	= {
 541			{
 542				.start	= REG_PTI_OFFSET,
 543				.end	= REG_PTI_OFFSET + REG_PTI_LENGTH - 1,
 544				.flags	= IORESOURCE_MEM,
 545			},
 546		},
 547		.id	= -1,
 548		.name	= "pti",
 549		.type	= INTEL_TH_OUTPUT,
 550		.otype	= GTH_PTI,
 551		.scrpd	= SCRPD_PTI_IS_PRIM_DEST,
 552	},
 553	{
 554		.nres	= 1,
 555		.res	= {
 556			{
 557				.start	= REG_PTI_OFFSET,
 558				.end	= REG_PTI_OFFSET + REG_PTI_LENGTH - 1,
 559				.flags	= IORESOURCE_MEM,
 560			},
 561		},
 562		.id	= -1,
 563		.name	= "lpp",
 564		.type	= INTEL_TH_OUTPUT,
 565		.otype	= GTH_LPP,
 566		.scrpd	= SCRPD_PTI_IS_PRIM_DEST,
 567	},
 568	{
 569		.nres	= 1,
 570		.res	= {
 571			{
 572				.start	= REG_DCIH_OFFSET,
 573				.end	= REG_DCIH_OFFSET + REG_DCIH_LENGTH - 1,
 574				.flags	= IORESOURCE_MEM,
 575			},
 576		},
 577		.id	= -1,
 578		.name	= "dcih",
 579		.type	= INTEL_TH_OUTPUT,
 580	},
 581};
 582
 583#ifdef CONFIG_MODULES
 584static void __intel_th_request_hub_module(struct work_struct *work)
 585{
 586	struct intel_th *th = container_of(work, struct intel_th,
 587					   request_module_work);
 588
 589	request_module("intel_th_%s", th->hub->name);
 590}
 591
 592static int intel_th_request_hub_module(struct intel_th *th)
 593{
 594	INIT_WORK(&th->request_module_work, __intel_th_request_hub_module);
 595	schedule_work(&th->request_module_work);
 596
 597	return 0;
 598}
 599
 600static void intel_th_request_hub_module_flush(struct intel_th *th)
 601{
 602	flush_work(&th->request_module_work);
 603}
 604#else
 605static inline int intel_th_request_hub_module(struct intel_th *th)
 606{
 607	return -EINVAL;
 608}
 609
 610static inline void intel_th_request_hub_module_flush(struct intel_th *th)
 611{
 612}
 613#endif /* CONFIG_MODULES */
 614
 615static struct intel_th_device *
 616intel_th_subdevice_alloc(struct intel_th *th,
 617			 const struct intel_th_subdevice *subdev)
 618{
 619	struct intel_th_device *thdev;
 620	struct resource res[3];
 621	unsigned int req = 0;
 622	int r, err;
 623
 624	thdev = intel_th_device_alloc(th, subdev->type, subdev->name,
 625				      subdev->id);
 626	if (!thdev)
 627		return ERR_PTR(-ENOMEM);
 628
 629	thdev->drvdata = th->drvdata;
 630
 631	memcpy(res, subdev->res,
 632	       sizeof(struct resource) * subdev->nres);
 633
 634	for (r = 0; r < subdev->nres; r++) {
 635		struct resource *devres = th->resource;
 636		int bar = TH_MMIO_CONFIG;
 637
 638		/*
 639		 * Take .end == 0 to mean 'take the whole bar',
 640		 * .start then tells us which bar it is. Default to
 641		 * TH_MMIO_CONFIG.
 642		 */
 643		if (!res[r].end && res[r].flags == IORESOURCE_MEM) {
 644			bar = res[r].start;
 645			err = -ENODEV;
 646			if (bar >= th->num_resources)
 647				goto fail_put_device;
 648			res[r].start = 0;
 649			res[r].end = resource_size(&devres[bar]) - 1;
 650		}
 651
 652		if (res[r].flags & IORESOURCE_MEM) {
 653			res[r].start	+= devres[bar].start;
 654			res[r].end	+= devres[bar].start;
 655
 656			dev_dbg(th->dev, "%s:%d @ %pR\n",
 657				subdev->name, r, &res[r]);
 658		} else if (res[r].flags & IORESOURCE_IRQ) {
 659			/*
 660			 * Only pass on the IRQ if we have useful interrupts:
 661			 * the ones that can be configured via MINTCTL.
 662			 */
 663			if (INTEL_TH_CAP(th, has_mintctl) && th->irq != -1)
 664				res[r].start = th->irq;
 665		}
 666	}
 667
 668	err = intel_th_device_add_resources(thdev, res, subdev->nres);
 669	if (err)
 670		goto fail_put_device;
 671
 672	if (subdev->type == INTEL_TH_OUTPUT) {
 673		if (subdev->mknode)
 674			thdev->dev.devt = MKDEV(th->major, th->num_thdevs);
 675		thdev->output.type = subdev->otype;
 676		thdev->output.port = -1;
 677		thdev->output.scratchpad = subdev->scrpd;
 678	} else if (subdev->type == INTEL_TH_SWITCH) {
 679		thdev->host_mode =
 680			INTEL_TH_CAP(th, host_mode_only) ? true : host_mode;
 681		th->hub = thdev;
 682	}
 683
 684	err = device_add(&thdev->dev);
 685	if (err)
 686		goto fail_free_res;
 687
 688	/* need switch driver to be loaded to enumerate the rest */
 689	if (subdev->type == INTEL_TH_SWITCH && !req) {
 690		err = intel_th_request_hub_module(th);
 691		if (!err)
 692			req++;
 693	}
 694
 695	return thdev;
 696
 697fail_free_res:
 698	kfree(thdev->resource);
 699
 700fail_put_device:
 701	put_device(&thdev->dev);
 702
 703	return ERR_PTR(err);
 704}
 705
 706/**
 707 * intel_th_output_enable() - find and enable a device for a given output type
 708 * @th:		Intel TH instance
 709 * @otype:	output type
 710 *
 711 * Go through the unallocated output devices, find the first one whos type
 712 * matches @otype and instantiate it. These devices are removed when the hub
 713 * device is removed, see intel_th_remove().
 714 */
 715int intel_th_output_enable(struct intel_th *th, unsigned int otype)
 716{
 717	struct intel_th_device *thdev;
 718	int src = 0, dst = 0;
 719
 720	for (src = 0, dst = 0; dst <= th->num_thdevs; src++, dst++) {
 721		for (; src < ARRAY_SIZE(intel_th_subdevices); src++) {
 722			if (intel_th_subdevices[src].type != INTEL_TH_OUTPUT)
 723				continue;
 724
 725			if (intel_th_subdevices[src].otype != otype)
 726				continue;
 727
 728			break;
 729		}
 730
 731		/* no unallocated matching subdevices */
 732		if (src == ARRAY_SIZE(intel_th_subdevices))
 733			return -ENODEV;
 734
 735		for (; dst < th->num_thdevs; dst++) {
 736			if (th->thdev[dst]->type != INTEL_TH_OUTPUT)
 737				continue;
 738
 739			if (th->thdev[dst]->output.type != otype)
 740				continue;
 741
 742			break;
 743		}
 744
 745		/*
 746		 * intel_th_subdevices[src] matches our requirements and is
 747		 * not matched in th::thdev[]
 748		 */
 749		if (dst == th->num_thdevs)
 750			goto found;
 751	}
 752
 753	return -ENODEV;
 754
 755found:
 756	thdev = intel_th_subdevice_alloc(th, &intel_th_subdevices[src]);
 757	if (IS_ERR(thdev))
 758		return PTR_ERR(thdev);
 759
 760	th->thdev[th->num_thdevs++] = thdev;
 761
 762	return 0;
 763}
 764EXPORT_SYMBOL_GPL(intel_th_output_enable);
 765
 766static int intel_th_populate(struct intel_th *th)
 767{
 768	int src;
 769
 770	/* create devices for each intel_th_subdevice */
 771	for (src = 0; src < ARRAY_SIZE(intel_th_subdevices); src++) {
 772		const struct intel_th_subdevice *subdev =
 773			&intel_th_subdevices[src];
 774		struct intel_th_device *thdev;
 775
 776		/* only allow SOURCE and SWITCH devices in host mode */
 777		if ((INTEL_TH_CAP(th, host_mode_only) || host_mode) &&
 778		    subdev->type == INTEL_TH_OUTPUT)
 779			continue;
 780
 781		/*
 782		 * don't enable port OUTPUTs in this path; SWITCH enables them
 783		 * via intel_th_output_enable()
 784		 */
 785		if (subdev->type == INTEL_TH_OUTPUT &&
 786		    subdev->otype != GTH_NONE)
 787			continue;
 788
 789		thdev = intel_th_subdevice_alloc(th, subdev);
 790		/* note: caller should free subdevices from th::thdev[] */
 791		if (IS_ERR(thdev)) {
 792			/* ENODEV for individual subdevices is allowed */
 793			if (PTR_ERR(thdev) == -ENODEV)
 794				continue;
 795
 796			return PTR_ERR(thdev);
 797		}
 798
 799		th->thdev[th->num_thdevs++] = thdev;
 800	}
 801
 802	return 0;
 803}
 804
 805static int intel_th_output_open(struct inode *inode, struct file *file)
 806{
 807	const struct file_operations *fops;
 808	struct intel_th_driver *thdrv;
 809	struct device *dev;
 810	int err;
 811
 812	dev = bus_find_device_by_devt(&intel_th_bus, inode->i_rdev);
 813	if (!dev || !dev->driver)
 814		return -ENODEV;
 815
 816	thdrv = to_intel_th_driver(dev->driver);
 817	fops = fops_get(thdrv->fops);
 818	if (!fops)
 819		return -ENODEV;
 820
 821	replace_fops(file, fops);
 822
 823	file->private_data = to_intel_th_device(dev);
 824
 825	if (file->f_op->open) {
 826		err = file->f_op->open(inode, file);
 827		return err;
 828	}
 829
 830	return 0;
 831}
 832
 833static const struct file_operations intel_th_output_fops = {
 834	.open	= intel_th_output_open,
 835	.llseek	= noop_llseek,
 836};
 837
 838static irqreturn_t intel_th_irq(int irq, void *data)
 839{
 840	struct intel_th *th = data;
 841	irqreturn_t ret = IRQ_NONE;
 842	struct intel_th_driver *d;
 843	int i;
 844
 845	for (i = 0; i < th->num_thdevs; i++) {
 846		if (th->thdev[i]->type != INTEL_TH_OUTPUT)
 847			continue;
 848
 849		d = to_intel_th_driver(th->thdev[i]->dev.driver);
 850		if (d && d->irq)
 851			ret |= d->irq(th->thdev[i]);
 852	}
 853
 854	return ret;
 855}
 856
 857/**
 858 * intel_th_alloc() - allocate a new Intel TH device and its subdevices
 859 * @dev:	parent device
 860 * @devres:	resources indexed by th_mmio_idx
 861 * @irq:	irq number
 862 */
 863struct intel_th *
 864intel_th_alloc(struct device *dev, const struct intel_th_drvdata *drvdata,
 865	       struct resource *devres, unsigned int ndevres)
 866{
 867	int err, r, nr_mmios = 0;
 868	struct intel_th *th;
 869
 870	th = kzalloc(sizeof(*th), GFP_KERNEL);
 871	if (!th)
 872		return ERR_PTR(-ENOMEM);
 873
 874	th->id = ida_alloc(&intel_th_ida, GFP_KERNEL);
 875	if (th->id < 0) {
 876		err = th->id;
 877		goto err_alloc;
 878	}
 879
 880	th->major = __register_chrdev(0, 0, TH_POSSIBLE_OUTPUTS,
 881				      "intel_th/output", &intel_th_output_fops);
 882	if (th->major < 0) {
 883		err = th->major;
 884		goto err_ida;
 885	}
 886	th->irq = -1;
 887	th->dev = dev;
 888	th->drvdata = drvdata;
 889
 890	for (r = 0; r < ndevres; r++)
 891		switch (devres[r].flags & IORESOURCE_TYPE_BITS) {
 892		case IORESOURCE_MEM:
 893			th->resource[nr_mmios++] = devres[r];
 894			break;
 895		case IORESOURCE_IRQ:
 896			err = devm_request_irq(dev, devres[r].start,
 897					       intel_th_irq, IRQF_SHARED,
 898					       dev_name(dev), th);
 899			if (err)
 900				goto err_chrdev;
 901
 902			if (th->irq == -1)
 903				th->irq = devres[r].start;
 904			th->num_irqs++;
 905			break;
 906		default:
 907			dev_warn(dev, "Unknown resource type %lx\n",
 908				 devres[r].flags);
 909			break;
 910		}
 911
 912	th->num_resources = nr_mmios;
 913
 914	dev_set_drvdata(dev, th);
 915
 916	pm_runtime_no_callbacks(dev);
 917	pm_runtime_put(dev);
 918	pm_runtime_allow(dev);
 919
 920	err = intel_th_populate(th);
 921	if (err) {
 922		/* free the subdevices and undo everything */
 923		intel_th_free(th);
 924		return ERR_PTR(err);
 925	}
 926
 927	return th;
 928
 929err_chrdev:
 930	__unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
 931			    "intel_th/output");
 932
 933err_ida:
 934	ida_free(&intel_th_ida, th->id);
 935
 936err_alloc:
 937	kfree(th);
 938
 939	return ERR_PTR(err);
 940}
 941EXPORT_SYMBOL_GPL(intel_th_alloc);
 942
 943void intel_th_free(struct intel_th *th)
 944{
 945	int i;
 946
 947	intel_th_request_hub_module_flush(th);
 948
 949	intel_th_device_remove(th->hub);
 950	for (i = 0; i < th->num_thdevs; i++) {
 951		if (th->thdev[i] != th->hub)
 952			intel_th_device_remove(th->thdev[i]);
 953		th->thdev[i] = NULL;
 954	}
 955
 956	th->num_thdevs = 0;
 957
 958	for (i = 0; i < th->num_irqs; i++)
 959		devm_free_irq(th->dev, th->irq + i, th);
 960
 961	pm_runtime_get_sync(th->dev);
 962	pm_runtime_forbid(th->dev);
 963
 964	__unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
 965			    "intel_th/output");
 966
 967	ida_free(&intel_th_ida, th->id);
 968
 969	kfree(th);
 970}
 971EXPORT_SYMBOL_GPL(intel_th_free);
 972
 973/**
 974 * intel_th_trace_enable() - enable tracing for an output device
 975 * @thdev:	output device that requests tracing be enabled
 976 */
 977int intel_th_trace_enable(struct intel_th_device *thdev)
 978{
 979	struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
 980	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 981
 982	if (WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH))
 983		return -EINVAL;
 984
 985	if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
 986		return -EINVAL;
 987
 988	pm_runtime_get_sync(&thdev->dev);
 989	hubdrv->enable(hub, &thdev->output);
 990
 991	return 0;
 992}
 993EXPORT_SYMBOL_GPL(intel_th_trace_enable);
 994
 995/**
 996 * intel_th_trace_switch() - execute a switch sequence
 997 * @thdev:	output device that requests tracing switch
 998 */
 999int intel_th_trace_switch(struct intel_th_device *thdev)
1000{
1001	struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
1002	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
1003
1004	if (WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH))
1005		return -EINVAL;
1006
1007	if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
1008		return -EINVAL;
1009
1010	hubdrv->trig_switch(hub, &thdev->output);
1011
1012	return 0;
1013}
1014EXPORT_SYMBOL_GPL(intel_th_trace_switch);
1015
1016/**
1017 * intel_th_trace_disable() - disable tracing for an output device
1018 * @thdev:	output device that requests tracing be disabled
1019 */
1020int intel_th_trace_disable(struct intel_th_device *thdev)
1021{
1022	struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
1023	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
1024
1025	WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH);
1026	if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
1027		return -EINVAL;
1028
1029	hubdrv->disable(hub, &thdev->output);
1030	pm_runtime_put(&thdev->dev);
1031
1032	return 0;
1033}
1034EXPORT_SYMBOL_GPL(intel_th_trace_disable);
1035
1036int intel_th_set_output(struct intel_th_device *thdev,
1037			unsigned int master)
1038{
1039	struct intel_th_device *hub = to_intel_th_hub(thdev);
1040	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
1041	int ret;
1042
1043	/* In host mode, this is up to the external debugger, do nothing. */
1044	if (hub->host_mode)
1045		return 0;
1046
1047	/*
1048	 * hub is instantiated together with the source device that
1049	 * calls here, so guaranteed to be present.
1050	 */
1051	hubdrv = to_intel_th_driver(hub->dev.driver);
1052	if (!hubdrv || !try_module_get(hubdrv->driver.owner))
1053		return -EINVAL;
1054
1055	if (!hubdrv->set_output) {
1056		ret = -ENOTSUPP;
1057		goto out;
1058	}
1059
1060	ret = hubdrv->set_output(hub, master);
1061
1062out:
1063	module_put(hubdrv->driver.owner);
1064	return ret;
1065}
1066EXPORT_SYMBOL_GPL(intel_th_set_output);
1067
1068static int __init intel_th_init(void)
1069{
1070	intel_th_debug_init();
1071
1072	return bus_register(&intel_th_bus);
1073}
1074subsys_initcall(intel_th_init);
1075
1076static void __exit intel_th_exit(void)
1077{
1078	intel_th_debug_done();
1079
1080	bus_unregister(&intel_th_bus);
1081}
1082module_exit(intel_th_exit);
1083
1084MODULE_LICENSE("GPL v2");
1085MODULE_DESCRIPTION("Intel(R) Trace Hub controller driver");
1086MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");