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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
32static bool host_mode __read_mostly;
33module_param(host_mode, bool, 0444);
34
35static DEFINE_IDA(intel_th_ida);
36
37static 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
49static int intel_th_child_remove(struct device *dev, void *data)
50{
51 device_release_driver(dev);
52
53 return 0;
54}
55
56static 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
93out:
94 if (ret)
95 thdrv->remove(thdev);
96
97out_pm:
98 if (ret)
99 pm_runtime_disable(dev);
100
101 return ret;
102}
103
104static 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
140static 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
148static void intel_th_device_free(struct intel_th_device *thdev);
149
150static void intel_th_device_release(struct device *dev)
151{
152 intel_th_device_free(to_intel_th_device(dev));
153}
154
155static struct device_type intel_th_source_device_type = {
156 .name = "intel_th_source_device",
157 .release = intel_th_device_release,
158};
159
160static 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
175static 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
192static 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
203static DEVICE_ATTR_RO(port);
204
205static 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 module_put(thdrv->driver.owner);
227 }
228
229 return ret;
230}
231
232static void intel_th_output_deactivate(struct intel_th_device *thdev)
233{
234 struct intel_th_driver *thdrv =
235 to_intel_th_driver_or_null(thdev->dev.driver);
236
237 if (!thdrv)
238 return;
239
240 if (thdrv->deactivate)
241 thdrv->deactivate(thdev);
242 else
243 intel_th_trace_disable(thdev);
244
245 pm_runtime_put(&thdev->dev);
246 module_put(thdrv->driver.owner);
247}
248
249static ssize_t active_show(struct device *dev, struct device_attribute *attr,
250 char *buf)
251{
252 struct intel_th_device *thdev = to_intel_th_device(dev);
253
254 return scnprintf(buf, PAGE_SIZE, "%d\n", thdev->output.active);
255}
256
257static ssize_t active_store(struct device *dev, struct device_attribute *attr,
258 const char *buf, size_t size)
259{
260 struct intel_th_device *thdev = to_intel_th_device(dev);
261 unsigned long val;
262 int ret;
263
264 ret = kstrtoul(buf, 10, &val);
265 if (ret)
266 return ret;
267
268 if (!!val != thdev->output.active) {
269 if (val)
270 ret = intel_th_output_activate(thdev);
271 else
272 intel_th_output_deactivate(thdev);
273 }
274
275 return ret ? ret : size;
276}
277
278static DEVICE_ATTR_RW(active);
279
280static struct attribute *intel_th_output_attrs[] = {
281 &dev_attr_port.attr,
282 &dev_attr_active.attr,
283 NULL,
284};
285
286ATTRIBUTE_GROUPS(intel_th_output);
287
288static struct device_type intel_th_output_device_type = {
289 .name = "intel_th_output_device",
290 .groups = intel_th_output_groups,
291 .release = intel_th_device_release,
292 .devnode = intel_th_output_devnode,
293};
294
295static struct device_type intel_th_switch_device_type = {
296 .name = "intel_th_switch_device",
297 .release = intel_th_device_release,
298};
299
300static struct device_type *intel_th_device_type[] = {
301 [INTEL_TH_SOURCE] = &intel_th_source_device_type,
302 [INTEL_TH_OUTPUT] = &intel_th_output_device_type,
303 [INTEL_TH_SWITCH] = &intel_th_switch_device_type,
304};
305
306int intel_th_driver_register(struct intel_th_driver *thdrv)
307{
308 if (!thdrv->probe || !thdrv->remove)
309 return -EINVAL;
310
311 thdrv->driver.bus = &intel_th_bus;
312
313 return driver_register(&thdrv->driver);
314}
315EXPORT_SYMBOL_GPL(intel_th_driver_register);
316
317void intel_th_driver_unregister(struct intel_th_driver *thdrv)
318{
319 driver_unregister(&thdrv->driver);
320}
321EXPORT_SYMBOL_GPL(intel_th_driver_unregister);
322
323static struct intel_th_device *
324intel_th_device_alloc(struct intel_th *th, unsigned int type, const char *name,
325 int id)
326{
327 struct device *parent;
328 struct intel_th_device *thdev;
329
330 if (type == INTEL_TH_SWITCH)
331 parent = th->dev;
332 else
333 parent = &th->hub->dev;
334
335 thdev = kzalloc(sizeof(*thdev) + strlen(name) + 1, GFP_KERNEL);
336 if (!thdev)
337 return NULL;
338
339 thdev->id = id;
340 thdev->type = type;
341
342 strcpy(thdev->name, name);
343 device_initialize(&thdev->dev);
344 thdev->dev.bus = &intel_th_bus;
345 thdev->dev.type = intel_th_device_type[type];
346 thdev->dev.parent = parent;
347 thdev->dev.dma_mask = parent->dma_mask;
348 thdev->dev.dma_parms = parent->dma_parms;
349 dma_set_coherent_mask(&thdev->dev, parent->coherent_dma_mask);
350 if (id >= 0)
351 dev_set_name(&thdev->dev, "%d-%s%d", th->id, name, id);
352 else
353 dev_set_name(&thdev->dev, "%d-%s", th->id, name);
354
355 return thdev;
356}
357
358static int intel_th_device_add_resources(struct intel_th_device *thdev,
359 struct resource *res, int nres)
360{
361 struct resource *r;
362
363 r = kmemdup(res, sizeof(*res) * nres, GFP_KERNEL);
364 if (!r)
365 return -ENOMEM;
366
367 thdev->resource = r;
368 thdev->num_resources = nres;
369
370 return 0;
371}
372
373static void intel_th_device_remove(struct intel_th_device *thdev)
374{
375 device_del(&thdev->dev);
376 put_device(&thdev->dev);
377}
378
379static void intel_th_device_free(struct intel_th_device *thdev)
380{
381 kfree(thdev->resource);
382 kfree(thdev);
383}
384
385/*
386 * Intel(R) Trace Hub subdevices
387 */
388static const struct intel_th_subdevice {
389 const char *name;
390 struct resource res[3];
391 unsigned nres;
392 unsigned type;
393 unsigned otype;
394 unsigned scrpd;
395 int id;
396} intel_th_subdevices[TH_SUBDEVICE_MAX] = {
397 {
398 .nres = 1,
399 .res = {
400 {
401 .start = REG_GTH_OFFSET,
402 .end = REG_GTH_OFFSET + REG_GTH_LENGTH - 1,
403 .flags = IORESOURCE_MEM,
404 },
405 },
406 .name = "gth",
407 .type = INTEL_TH_SWITCH,
408 .id = -1,
409 },
410 {
411 .nres = 2,
412 .res = {
413 {
414 .start = REG_MSU_OFFSET,
415 .end = REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
416 .flags = IORESOURCE_MEM,
417 },
418 {
419 .start = BUF_MSU_OFFSET,
420 .end = BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
421 .flags = IORESOURCE_MEM,
422 },
423 },
424 .name = "msc",
425 .id = 0,
426 .type = INTEL_TH_OUTPUT,
427 .otype = GTH_MSU,
428 .scrpd = SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC0_IS_ENABLED,
429 },
430 {
431 .nres = 2,
432 .res = {
433 {
434 .start = REG_MSU_OFFSET,
435 .end = REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
436 .flags = IORESOURCE_MEM,
437 },
438 {
439 .start = BUF_MSU_OFFSET,
440 .end = BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
441 .flags = IORESOURCE_MEM,
442 },
443 },
444 .name = "msc",
445 .id = 1,
446 .type = INTEL_TH_OUTPUT,
447 .otype = GTH_MSU,
448 .scrpd = SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC1_IS_ENABLED,
449 },
450 {
451 .nres = 2,
452 .res = {
453 {
454 .start = REG_STH_OFFSET,
455 .end = REG_STH_OFFSET + REG_STH_LENGTH - 1,
456 .flags = IORESOURCE_MEM,
457 },
458 {
459 .start = TH_MMIO_SW,
460 .end = 0,
461 .flags = IORESOURCE_MEM,
462 },
463 },
464 .id = -1,
465 .name = "sth",
466 .type = INTEL_TH_SOURCE,
467 },
468 {
469 .nres = 1,
470 .res = {
471 {
472 .start = REG_PTI_OFFSET,
473 .end = REG_PTI_OFFSET + REG_PTI_LENGTH - 1,
474 .flags = IORESOURCE_MEM,
475 },
476 },
477 .id = -1,
478 .name = "pti",
479 .type = INTEL_TH_OUTPUT,
480 .otype = GTH_PTI,
481 .scrpd = SCRPD_PTI_IS_PRIM_DEST,
482 },
483 {
484 .nres = 1,
485 .res = {
486 {
487 .start = REG_DCIH_OFFSET,
488 .end = REG_DCIH_OFFSET + REG_DCIH_LENGTH - 1,
489 .flags = IORESOURCE_MEM,
490 },
491 },
492 .id = -1,
493 .name = "dcih",
494 .type = INTEL_TH_OUTPUT,
495 },
496};
497
498#ifdef CONFIG_MODULES
499static void __intel_th_request_hub_module(struct work_struct *work)
500{
501 struct intel_th *th = container_of(work, struct intel_th,
502 request_module_work);
503
504 request_module("intel_th_%s", th->hub->name);
505}
506
507static int intel_th_request_hub_module(struct intel_th *th)
508{
509 INIT_WORK(&th->request_module_work, __intel_th_request_hub_module);
510 schedule_work(&th->request_module_work);
511
512 return 0;
513}
514
515static void intel_th_request_hub_module_flush(struct intel_th *th)
516{
517 flush_work(&th->request_module_work);
518}
519#else
520static inline int intel_th_request_hub_module(struct intel_th *th)
521{
522 return -EINVAL;
523}
524
525static inline void intel_th_request_hub_module_flush(struct intel_th *th)
526{
527}
528#endif /* CONFIG_MODULES */
529
530static int intel_th_populate(struct intel_th *th, struct resource *devres,
531 unsigned int ndevres, int irq)
532{
533 struct resource res[3];
534 unsigned int req = 0;
535 int src, dst, err;
536
537 /* create devices for each intel_th_subdevice */
538 for (src = 0, dst = 0; src < ARRAY_SIZE(intel_th_subdevices); src++) {
539 const struct intel_th_subdevice *subdev =
540 &intel_th_subdevices[src];
541 struct intel_th_device *thdev;
542 int r;
543
544 /* only allow SOURCE and SWITCH devices in host mode */
545 if (host_mode && subdev->type == INTEL_TH_OUTPUT)
546 continue;
547
548 thdev = intel_th_device_alloc(th, subdev->type, subdev->name,
549 subdev->id);
550 if (!thdev) {
551 err = -ENOMEM;
552 goto kill_subdevs;
553 }
554
555 memcpy(res, subdev->res,
556 sizeof(struct resource) * subdev->nres);
557
558 for (r = 0; r < subdev->nres; r++) {
559 int bar = TH_MMIO_CONFIG;
560
561 /*
562 * Take .end == 0 to mean 'take the whole bar',
563 * .start then tells us which bar it is. Default to
564 * TH_MMIO_CONFIG.
565 */
566 if (!res[r].end && res[r].flags == IORESOURCE_MEM) {
567 bar = res[r].start;
568 res[r].start = 0;
569 res[r].end = resource_size(&devres[bar]) - 1;
570 }
571
572 if (res[r].flags & IORESOURCE_MEM) {
573 res[r].start += devres[bar].start;
574 res[r].end += devres[bar].start;
575
576 dev_dbg(th->dev, "%s:%d @ %pR\n",
577 subdev->name, r, &res[r]);
578 } else if (res[r].flags & IORESOURCE_IRQ) {
579 res[r].start = irq;
580 }
581 }
582
583 err = intel_th_device_add_resources(thdev, res, subdev->nres);
584 if (err) {
585 put_device(&thdev->dev);
586 goto kill_subdevs;
587 }
588
589 if (subdev->type == INTEL_TH_OUTPUT) {
590 thdev->dev.devt = MKDEV(th->major, dst);
591 thdev->output.type = subdev->otype;
592 thdev->output.port = -1;
593 thdev->output.scratchpad = subdev->scrpd;
594 } else if (subdev->type == INTEL_TH_SWITCH) {
595 thdev->host_mode = host_mode;
596 }
597
598 err = device_add(&thdev->dev);
599 if (err) {
600 put_device(&thdev->dev);
601 goto kill_subdevs;
602 }
603
604 /* need switch driver to be loaded to enumerate the rest */
605 if (subdev->type == INTEL_TH_SWITCH && !req) {
606 th->hub = thdev;
607 err = intel_th_request_hub_module(th);
608 if (!err)
609 req++;
610 }
611
612 th->thdev[dst++] = thdev;
613 }
614
615 return 0;
616
617kill_subdevs:
618 for (; dst >= 0; dst--)
619 intel_th_device_remove(th->thdev[dst]);
620
621 return err;
622}
623
624static int match_devt(struct device *dev, void *data)
625{
626 dev_t devt = (dev_t)(unsigned long)data;
627
628 return dev->devt == devt;
629}
630
631static int intel_th_output_open(struct inode *inode, struct file *file)
632{
633 const struct file_operations *fops;
634 struct intel_th_driver *thdrv;
635 struct device *dev;
636 int err;
637
638 dev = bus_find_device(&intel_th_bus, NULL,
639 (void *)(unsigned long)inode->i_rdev,
640 match_devt);
641 if (!dev || !dev->driver)
642 return -ENODEV;
643
644 thdrv = to_intel_th_driver(dev->driver);
645 fops = fops_get(thdrv->fops);
646 if (!fops)
647 return -ENODEV;
648
649 replace_fops(file, fops);
650
651 file->private_data = to_intel_th_device(dev);
652
653 if (file->f_op->open) {
654 err = file->f_op->open(inode, file);
655 return err;
656 }
657
658 return 0;
659}
660
661static const struct file_operations intel_th_output_fops = {
662 .open = intel_th_output_open,
663 .llseek = noop_llseek,
664};
665
666/**
667 * intel_th_alloc() - allocate a new Intel TH device and its subdevices
668 * @dev: parent device
669 * @devres: parent's resources
670 * @ndevres: number of resources
671 * @irq: irq number
672 */
673struct intel_th *
674intel_th_alloc(struct device *dev, struct resource *devres,
675 unsigned int ndevres, int irq)
676{
677 struct intel_th *th;
678 int err;
679
680 th = kzalloc(sizeof(*th), GFP_KERNEL);
681 if (!th)
682 return ERR_PTR(-ENOMEM);
683
684 th->id = ida_simple_get(&intel_th_ida, 0, 0, GFP_KERNEL);
685 if (th->id < 0) {
686 err = th->id;
687 goto err_alloc;
688 }
689
690 th->major = __register_chrdev(0, 0, TH_POSSIBLE_OUTPUTS,
691 "intel_th/output", &intel_th_output_fops);
692 if (th->major < 0) {
693 err = th->major;
694 goto err_ida;
695 }
696 th->dev = dev;
697
698 dev_set_drvdata(dev, th);
699
700 pm_runtime_no_callbacks(dev);
701 pm_runtime_put(dev);
702 pm_runtime_allow(dev);
703
704 err = intel_th_populate(th, devres, ndevres, irq);
705 if (err)
706 goto err_chrdev;
707
708 return th;
709
710err_chrdev:
711 pm_runtime_forbid(dev);
712
713 __unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
714 "intel_th/output");
715
716err_ida:
717 ida_simple_remove(&intel_th_ida, th->id);
718
719err_alloc:
720 kfree(th);
721
722 return ERR_PTR(err);
723}
724EXPORT_SYMBOL_GPL(intel_th_alloc);
725
726void intel_th_free(struct intel_th *th)
727{
728 int i;
729
730 intel_th_request_hub_module_flush(th);
731 for (i = 0; i < TH_SUBDEVICE_MAX; i++)
732 if (th->thdev[i] && th->thdev[i] != th->hub)
733 intel_th_device_remove(th->thdev[i]);
734
735 intel_th_device_remove(th->hub);
736
737 pm_runtime_get_sync(th->dev);
738 pm_runtime_forbid(th->dev);
739
740 __unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
741 "intel_th/output");
742
743 ida_simple_remove(&intel_th_ida, th->id);
744
745 kfree(th);
746}
747EXPORT_SYMBOL_GPL(intel_th_free);
748
749/**
750 * intel_th_trace_enable() - enable tracing for an output device
751 * @thdev: output device that requests tracing be enabled
752 */
753int intel_th_trace_enable(struct intel_th_device *thdev)
754{
755 struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
756 struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
757
758 if (WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH))
759 return -EINVAL;
760
761 if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
762 return -EINVAL;
763
764 pm_runtime_get_sync(&thdev->dev);
765 hubdrv->enable(hub, &thdev->output);
766
767 return 0;
768}
769EXPORT_SYMBOL_GPL(intel_th_trace_enable);
770
771/**
772 * intel_th_trace_disable() - disable tracing for an output device
773 * @thdev: output device that requests tracing be disabled
774 */
775int intel_th_trace_disable(struct intel_th_device *thdev)
776{
777 struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
778 struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
779
780 WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH);
781 if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
782 return -EINVAL;
783
784 hubdrv->disable(hub, &thdev->output);
785 pm_runtime_put(&thdev->dev);
786
787 return 0;
788}
789EXPORT_SYMBOL_GPL(intel_th_trace_disable);
790
791int intel_th_set_output(struct intel_th_device *thdev,
792 unsigned int master)
793{
794 struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
795 struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
796
797 if (!hubdrv->set_output)
798 return -ENOTSUPP;
799
800 return hubdrv->set_output(hub, master);
801}
802EXPORT_SYMBOL_GPL(intel_th_set_output);
803
804static int __init intel_th_init(void)
805{
806 intel_th_debug_init();
807
808 return bus_register(&intel_th_bus);
809}
810subsys_initcall(intel_th_init);
811
812static void __exit intel_th_exit(void)
813{
814 intel_th_debug_done();
815
816 bus_unregister(&intel_th_bus);
817}
818module_exit(intel_th_exit);
819
820MODULE_LICENSE("GPL v2");
821MODULE_DESCRIPTION("Intel(R) Trace Hub controller driver");
822MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");