1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2021-2022 NVIDIA Corporation
4 *
5 * Author: Dipen Patel <dipenp@nvidia.com>
6 */
7
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/err.h>
11 #include <linux/slab.h>
12 #include <linux/of.h>
13 #include <linux/mutex.h>
14 #include <linux/uaccess.h>
15 #include <linux/hte.h>
16 #include <linux/delay.h>
17 #include <linux/debugfs.h>
18 #include <linux/device.h>
19
20 /* Global list of the HTE devices */
21 static DEFINE_SPINLOCK(hte_lock);
22 static LIST_HEAD(hte_devices);
23
24 enum {
25 HTE_TS_REGISTERED,
26 HTE_TS_REQ,
27 HTE_TS_DISABLE,
28 HTE_TS_QUEUE_WK,
29 };
30
31 /**
32 * struct hte_ts_info - Information related to requested timestamp.
33 *
34 * @xlated_id: Timestamp ID as understood between HTE subsys and HTE provider,
35 * See xlate callback API.
36 * @flags: Flags holding state information.
37 * @hte_cb_flags: Callback related flags.
38 * @seq: Timestamp sequence counter.
39 * @line_name: HTE allocated line name.
40 * @free_attr_name: If set, free the attr name.
41 * @cb: A nonsleeping callback function provided by clients.
42 * @tcb: A secondary sleeping callback function provided by clients.
43 * @dropped_ts: Dropped timestamps.
44 * @slock: Spin lock to synchronize between disable/enable,
45 * request/release APIs.
46 * @cb_work: callback workqueue, used when tcb is specified.
47 * @req_mlock: Lock during timestamp request/release APIs.
48 * @ts_dbg_root: Root for the debug fs.
49 * @gdev: HTE abstract device that this timestamp information belongs to.
50 * @cl_data: Client specific data.
51 */
52 struct hte_ts_info {
53 u32 xlated_id;
54 unsigned long flags;
55 unsigned long hte_cb_flags;
56 u64 seq;
57 char *line_name;
58 bool free_attr_name;
59 hte_ts_cb_t cb;
60 hte_ts_sec_cb_t tcb;
61 atomic_t dropped_ts;
62 spinlock_t slock;
63 struct work_struct cb_work;
64 struct mutex req_mlock;
65 struct dentry *ts_dbg_root;
66 struct hte_device *gdev;
67 void *cl_data;
68 };
69
70 /**
71 * struct hte_device - HTE abstract device
72 * @nlines: Number of entities this device supports.
73 * @ts_req: Total number of entities requested.
74 * @sdev: Device used at various debug prints.
75 * @dbg_root: Root directory for debug fs.
76 * @list: List node to store hte_device for each provider.
77 * @chip: HTE chip providing this HTE device.
78 * @owner: helps prevent removal of modules when in use.
79 * @ei: Timestamp information.
80 */
81 struct hte_device {
82 u32 nlines;
83 atomic_t ts_req;
84 struct device *sdev;
85 struct dentry *dbg_root;
86 struct list_head list;
87 struct hte_chip *chip;
88 struct module *owner;
89 struct hte_ts_info ei[] __counted_by(nlines);
90 };
91
92 #ifdef CONFIG_DEBUG_FS
93
94 static struct dentry *hte_root;
95
hte_subsys_dbgfs_init(void)96 static int __init hte_subsys_dbgfs_init(void)
97 {
98 /* creates /sys/kernel/debug/hte/ */
99 hte_root = debugfs_create_dir("hte", NULL);
100
101 return 0;
102 }
103 subsys_initcall(hte_subsys_dbgfs_init);
104
hte_chip_dbgfs_init(struct hte_device * gdev)105 static void hte_chip_dbgfs_init(struct hte_device *gdev)
106 {
107 const struct hte_chip *chip = gdev->chip;
108 const char *name = chip->name ? chip->name : dev_name(chip->dev);
109
110 gdev->dbg_root = debugfs_create_dir(name, hte_root);
111
112 debugfs_create_atomic_t("ts_requested", 0444, gdev->dbg_root,
113 &gdev->ts_req);
114 debugfs_create_u32("total_ts", 0444, gdev->dbg_root,
115 &gdev->nlines);
116 }
117
hte_ts_dbgfs_init(const char * name,struct hte_ts_info * ei)118 static void hte_ts_dbgfs_init(const char *name, struct hte_ts_info *ei)
119 {
120 if (!ei->gdev->dbg_root || !name)
121 return;
122
123 ei->ts_dbg_root = debugfs_create_dir(name, ei->gdev->dbg_root);
124
125 debugfs_create_atomic_t("dropped_timestamps", 0444, ei->ts_dbg_root,
126 &ei->dropped_ts);
127 }
128
129 #else
130
hte_chip_dbgfs_init(struct hte_device * gdev)131 static void hte_chip_dbgfs_init(struct hte_device *gdev)
132 {
133 }
134
hte_ts_dbgfs_init(const char * name,struct hte_ts_info * ei)135 static void hte_ts_dbgfs_init(const char *name, struct hte_ts_info *ei)
136 {
137 }
138
139 #endif
140
141 /**
142 * hte_ts_put() - Release and disable timestamp for the given desc.
143 *
144 * @desc: timestamp descriptor.
145 *
146 * Context: debugfs_remove_recursive() function call may use sleeping locks,
147 * not suitable from atomic context.
148 * Returns: 0 on success or a negative error code on failure.
149 */
hte_ts_put(struct hte_ts_desc * desc)150 int hte_ts_put(struct hte_ts_desc *desc)
151 {
152 int ret = 0;
153 unsigned long flag;
154 struct hte_device *gdev;
155 struct hte_ts_info *ei;
156
157 if (!desc)
158 return -EINVAL;
159
160 ei = desc->hte_data;
161
162 if (!ei || !ei->gdev)
163 return -EINVAL;
164
165 gdev = ei->gdev;
166
167 mutex_lock(&ei->req_mlock);
168
169 if (unlikely(!test_bit(HTE_TS_REQ, &ei->flags) &&
170 !test_bit(HTE_TS_REGISTERED, &ei->flags))) {
171 dev_info(gdev->sdev, "id:%d is not requested\n",
172 desc->attr.line_id);
173 ret = -EINVAL;
174 goto unlock;
175 }
176
177 if (unlikely(!test_bit(HTE_TS_REQ, &ei->flags) &&
178 test_bit(HTE_TS_REGISTERED, &ei->flags))) {
179 dev_info(gdev->sdev, "id:%d is registered but not requested\n",
180 desc->attr.line_id);
181 ret = -EINVAL;
182 goto unlock;
183 }
184
185 if (test_bit(HTE_TS_REQ, &ei->flags) &&
186 !test_bit(HTE_TS_REGISTERED, &ei->flags)) {
187 clear_bit(HTE_TS_REQ, &ei->flags);
188 desc->hte_data = NULL;
189 ret = 0;
190 goto mod_put;
191 }
192
193 ret = gdev->chip->ops->release(gdev->chip, desc, ei->xlated_id);
194 if (ret) {
195 dev_err(gdev->sdev, "id: %d free failed\n",
196 desc->attr.line_id);
197 goto unlock;
198 }
199
200 kfree(ei->line_name);
201 if (ei->free_attr_name)
202 kfree_const(desc->attr.name);
203
204 debugfs_remove_recursive(ei->ts_dbg_root);
205
206 spin_lock_irqsave(&ei->slock, flag);
207
208 if (test_bit(HTE_TS_QUEUE_WK, &ei->flags)) {
209 spin_unlock_irqrestore(&ei->slock, flag);
210 flush_work(&ei->cb_work);
211 spin_lock_irqsave(&ei->slock, flag);
212 }
213
214 atomic_dec(&gdev->ts_req);
215 atomic_set(&ei->dropped_ts, 0);
216
217 ei->seq = 1;
218 ei->flags = 0;
219 desc->hte_data = NULL;
220
221 spin_unlock_irqrestore(&ei->slock, flag);
222
223 ei->cb = NULL;
224 ei->tcb = NULL;
225 ei->cl_data = NULL;
226
227 mod_put:
228 module_put(gdev->owner);
229 unlock:
230 mutex_unlock(&ei->req_mlock);
231 dev_dbg(gdev->sdev, "release id: %d\n", desc->attr.line_id);
232
233 return ret;
234 }
235 EXPORT_SYMBOL_GPL(hte_ts_put);
236
hte_ts_dis_en_common(struct hte_ts_desc * desc,bool en)237 static int hte_ts_dis_en_common(struct hte_ts_desc *desc, bool en)
238 {
239 u32 ts_id;
240 struct hte_device *gdev;
241 struct hte_ts_info *ei;
242 int ret;
243 unsigned long flag;
244
245 if (!desc)
246 return -EINVAL;
247
248 ei = desc->hte_data;
249
250 if (!ei || !ei->gdev)
251 return -EINVAL;
252
253 gdev = ei->gdev;
254 ts_id = desc->attr.line_id;
255
256 mutex_lock(&ei->req_mlock);
257
258 if (!test_bit(HTE_TS_REGISTERED, &ei->flags)) {
259 dev_dbg(gdev->sdev, "id:%d is not registered", ts_id);
260 ret = -EUSERS;
261 goto out;
262 }
263
264 spin_lock_irqsave(&ei->slock, flag);
265
266 if (en) {
267 if (!test_bit(HTE_TS_DISABLE, &ei->flags)) {
268 ret = 0;
269 goto out_unlock;
270 }
271
272 spin_unlock_irqrestore(&ei->slock, flag);
273 ret = gdev->chip->ops->enable(gdev->chip, ei->xlated_id);
274 if (ret) {
275 dev_warn(gdev->sdev, "id: %d enable failed\n",
276 ts_id);
277 goto out;
278 }
279
280 spin_lock_irqsave(&ei->slock, flag);
281 clear_bit(HTE_TS_DISABLE, &ei->flags);
282 } else {
283 if (test_bit(HTE_TS_DISABLE, &ei->flags)) {
284 ret = 0;
285 goto out_unlock;
286 }
287
288 spin_unlock_irqrestore(&ei->slock, flag);
289 ret = gdev->chip->ops->disable(gdev->chip, ei->xlated_id);
290 if (ret) {
291 dev_warn(gdev->sdev, "id: %d disable failed\n",
292 ts_id);
293 goto out;
294 }
295
296 spin_lock_irqsave(&ei->slock, flag);
297 set_bit(HTE_TS_DISABLE, &ei->flags);
298 }
299
300 out_unlock:
301 spin_unlock_irqrestore(&ei->slock, flag);
302 out:
303 mutex_unlock(&ei->req_mlock);
304 return ret;
305 }
306
307 /**
308 * hte_disable_ts() - Disable timestamp on given descriptor.
309 *
310 * The API does not release any resources associated with desc.
311 *
312 * @desc: ts descriptor, this is the same as returned by the request API.
313 *
314 * Context: Holds mutex lock, not suitable from atomic context.
315 * Returns: 0 on success or a negative error code on failure.
316 */
hte_disable_ts(struct hte_ts_desc * desc)317 int hte_disable_ts(struct hte_ts_desc *desc)
318 {
319 return hte_ts_dis_en_common(desc, false);
320 }
321 EXPORT_SYMBOL_GPL(hte_disable_ts);
322
323 /**
324 * hte_enable_ts() - Enable timestamp on given descriptor.
325 *
326 * @desc: ts descriptor, this is the same as returned by the request API.
327 *
328 * Context: Holds mutex lock, not suitable from atomic context.
329 * Returns: 0 on success or a negative error code on failure.
330 */
hte_enable_ts(struct hte_ts_desc * desc)331 int hte_enable_ts(struct hte_ts_desc *desc)
332 {
333 return hte_ts_dis_en_common(desc, true);
334 }
335 EXPORT_SYMBOL_GPL(hte_enable_ts);
336
hte_do_cb_work(struct work_struct * w)337 static void hte_do_cb_work(struct work_struct *w)
338 {
339 unsigned long flag;
340 struct hte_ts_info *ei = container_of(w, struct hte_ts_info, cb_work);
341
342 if (unlikely(!ei->tcb))
343 return;
344
345 ei->tcb(ei->cl_data);
346
347 spin_lock_irqsave(&ei->slock, flag);
348 clear_bit(HTE_TS_QUEUE_WK, &ei->flags);
349 spin_unlock_irqrestore(&ei->slock, flag);
350 }
351
__hte_req_ts(struct hte_ts_desc * desc,hte_ts_cb_t cb,hte_ts_sec_cb_t tcb,void * data)352 static int __hte_req_ts(struct hte_ts_desc *desc, hte_ts_cb_t cb,
353 hte_ts_sec_cb_t tcb, void *data)
354 {
355 int ret;
356 struct hte_device *gdev;
357 struct hte_ts_info *ei = desc->hte_data;
358
359 gdev = ei->gdev;
360 /*
361 * There is a chance that multiple consumers requesting same entity,
362 * lock here.
363 */
364 mutex_lock(&ei->req_mlock);
365
366 if (test_bit(HTE_TS_REGISTERED, &ei->flags) ||
367 !test_bit(HTE_TS_REQ, &ei->flags)) {
368 dev_dbg(gdev->chip->dev, "id:%u req failed\n",
369 desc->attr.line_id);
370 ret = -EUSERS;
371 goto unlock;
372 }
373
374 ei->cb = cb;
375 ei->tcb = tcb;
376 if (tcb)
377 INIT_WORK(&ei->cb_work, hte_do_cb_work);
378
379 ret = gdev->chip->ops->request(gdev->chip, desc, ei->xlated_id);
380 if (ret < 0) {
381 dev_err(gdev->chip->dev, "ts request failed\n");
382 goto unlock;
383 }
384
385 ei->cl_data = data;
386 ei->seq = 1;
387
388 atomic_inc(&gdev->ts_req);
389
390 if (desc->attr.name)
391 ei->line_name = NULL;
392 else
393 ei->line_name = kasprintf(GFP_KERNEL, "ts_%u", desc->attr.line_id);
394
395 hte_ts_dbgfs_init(desc->attr.name == NULL ?
396 ei->line_name : desc->attr.name, ei);
397 set_bit(HTE_TS_REGISTERED, &ei->flags);
398
399 dev_dbg(gdev->chip->dev, "id: %u, xlated id:%u",
400 desc->attr.line_id, ei->xlated_id);
401
402 ret = 0;
403
404 unlock:
405 mutex_unlock(&ei->req_mlock);
406
407 return ret;
408 }
409
hte_bind_ts_info_locked(struct hte_ts_info * ei,struct hte_ts_desc * desc,u32 x_id)410 static int hte_bind_ts_info_locked(struct hte_ts_info *ei,
411 struct hte_ts_desc *desc, u32 x_id)
412 {
413 int ret = 0;
414
415 mutex_lock(&ei->req_mlock);
416
417 if (test_bit(HTE_TS_REQ, &ei->flags)) {
418 dev_dbg(ei->gdev->chip->dev, "id:%u is already requested\n",
419 desc->attr.line_id);
420 ret = -EUSERS;
421 goto out;
422 }
423
424 set_bit(HTE_TS_REQ, &ei->flags);
425 desc->hte_data = ei;
426 ei->xlated_id = x_id;
427
428 out:
429 mutex_unlock(&ei->req_mlock);
430
431 return ret;
432 }
433
of_node_to_htedevice(struct device_node * np)434 static struct hte_device *of_node_to_htedevice(struct device_node *np)
435 {
436 struct hte_device *gdev;
437
438 spin_lock(&hte_lock);
439
440 list_for_each_entry(gdev, &hte_devices, list)
441 if (gdev->chip && gdev->chip->dev &&
442 device_match_of_node(gdev->chip->dev, np)) {
443 spin_unlock(&hte_lock);
444 return gdev;
445 }
446
447 spin_unlock(&hte_lock);
448
449 return ERR_PTR(-ENODEV);
450 }
451
hte_find_dev_from_linedata(struct hte_ts_desc * desc)452 static struct hte_device *hte_find_dev_from_linedata(struct hte_ts_desc *desc)
453 {
454 struct hte_device *gdev;
455
456 spin_lock(&hte_lock);
457
458 list_for_each_entry(gdev, &hte_devices, list)
459 if (gdev->chip && gdev->chip->match_from_linedata) {
460 if (!gdev->chip->match_from_linedata(gdev->chip, desc))
461 continue;
462 spin_unlock(&hte_lock);
463 return gdev;
464 }
465
466 spin_unlock(&hte_lock);
467
468 return ERR_PTR(-ENODEV);
469 }
470
471 /**
472 * of_hte_req_count - Return the number of entities to timestamp.
473 *
474 * The function returns the total count of the requested entities to timestamp
475 * by parsing device tree.
476 *
477 * @dev: The HTE consumer.
478 *
479 * Returns: Positive number on success, -ENOENT if no entries,
480 * -EINVAL for other errors.
481 */
of_hte_req_count(struct device * dev)482 int of_hte_req_count(struct device *dev)
483 {
484 int count;
485
486 if (!dev || !dev->of_node)
487 return -EINVAL;
488
489 count = of_count_phandle_with_args(dev->of_node, "timestamps",
490 "#timestamp-cells");
491
492 return count ? count : -ENOENT;
493 }
494 EXPORT_SYMBOL_GPL(of_hte_req_count);
495
hte_get_dev(struct hte_ts_desc * desc)496 static inline struct hte_device *hte_get_dev(struct hte_ts_desc *desc)
497 {
498 return hte_find_dev_from_linedata(desc);
499 }
500
hte_of_get_dev(struct device * dev,struct hte_ts_desc * desc,int index,struct of_phandle_args * args,bool * free_name)501 static struct hte_device *hte_of_get_dev(struct device *dev,
502 struct hte_ts_desc *desc,
503 int index,
504 struct of_phandle_args *args,
505 bool *free_name)
506 {
507 int ret;
508 struct device_node *np;
509 char *temp;
510
511 if (!dev->of_node)
512 return ERR_PTR(-EINVAL);
513
514 np = dev->of_node;
515
516 if (!of_property_present(np, "timestamp-names")) {
517 /* Let hte core construct it during request time */
518 desc->attr.name = NULL;
519 } else {
520 ret = of_property_read_string_index(np, "timestamp-names",
521 index, &desc->attr.name);
522 if (ret) {
523 pr_err("can't parse \"timestamp-names\" property\n");
524 return ERR_PTR(ret);
525 }
526 *free_name = false;
527 if (desc->attr.name) {
528 temp = skip_spaces(desc->attr.name);
529 if (!*temp)
530 desc->attr.name = NULL;
531 }
532 }
533
534 ret = of_parse_phandle_with_args(np, "timestamps", "#timestamp-cells",
535 index, args);
536 if (ret) {
537 pr_err("%s(): can't parse \"timestamps\" property\n",
538 __func__);
539 return ERR_PTR(ret);
540 }
541
542 of_node_put(args->np);
543
544 return of_node_to_htedevice(args->np);
545 }
546
547 /**
548 * hte_ts_get() - The function to initialize and obtain HTE desc.
549 *
550 * The function initializes the consumer provided HTE descriptor. If consumer
551 * has device tree node, index is used to parse the line id and other details.
552 * The function needs to be called before using any request APIs.
553 *
554 * @dev: HTE consumer/client device, used in case of parsing device tree node.
555 * @desc: Pre-allocated timestamp descriptor.
556 * @index: The index will be used as an index to parse line_id from the
557 * device tree node if node is present.
558 *
559 * Context: Holds mutex lock.
560 * Returns: Returns 0 on success or negative error code on failure.
561 */
hte_ts_get(struct device * dev,struct hte_ts_desc * desc,int index)562 int hte_ts_get(struct device *dev, struct hte_ts_desc *desc, int index)
563 {
564 struct hte_device *gdev;
565 struct hte_ts_info *ei;
566 const struct fwnode_handle *fwnode;
567 struct of_phandle_args args;
568 u32 xlated_id;
569 int ret;
570 bool free_name = false;
571
572 if (!desc)
573 return -EINVAL;
574
575 fwnode = dev ? dev_fwnode(dev) : NULL;
576
577 if (is_of_node(fwnode))
578 gdev = hte_of_get_dev(dev, desc, index, &args, &free_name);
579 else
580 gdev = hte_get_dev(desc);
581
582 if (IS_ERR(gdev)) {
583 pr_err("%s() no hte dev found\n", __func__);
584 return PTR_ERR(gdev);
585 }
586
587 if (!try_module_get(gdev->owner))
588 return -ENODEV;
589
590 if (!gdev->chip) {
591 pr_err("%s(): requested id does not have provider\n",
592 __func__);
593 ret = -ENODEV;
594 goto put;
595 }
596
597 if (is_of_node(fwnode)) {
598 if (!gdev->chip->xlate_of)
599 ret = -EINVAL;
600 else
601 ret = gdev->chip->xlate_of(gdev->chip, &args,
602 desc, &xlated_id);
603 } else {
604 if (!gdev->chip->xlate_plat)
605 ret = -EINVAL;
606 else
607 ret = gdev->chip->xlate_plat(gdev->chip, desc,
608 &xlated_id);
609 }
610
611 if (ret < 0)
612 goto put;
613
614 ei = &gdev->ei[xlated_id];
615
616 ret = hte_bind_ts_info_locked(ei, desc, xlated_id);
617 if (ret)
618 goto put;
619
620 ei->free_attr_name = free_name;
621
622 return 0;
623
624 put:
625 module_put(gdev->owner);
626 return ret;
627 }
628 EXPORT_SYMBOL_GPL(hte_ts_get);
629
__devm_hte_release_ts(void * res)630 static void __devm_hte_release_ts(void *res)
631 {
632 hte_ts_put(res);
633 }
634
635 /**
636 * hte_request_ts_ns() - The API to request and enable hardware timestamp in
637 * nanoseconds.
638 *
639 * The entity is provider specific for example, GPIO lines, signals, buses
640 * etc...The API allocates necessary resources and enables the timestamp.
641 *
642 * @desc: Pre-allocated and initialized timestamp descriptor.
643 * @cb: Callback to push the timestamp data to consumer.
644 * @tcb: Optional callback. If its provided, subsystem initializes
645 * workqueue. It is called when cb returns HTE_RUN_SECOND_CB.
646 * @data: Client data, used during cb and tcb callbacks.
647 *
648 * Context: Holds mutex lock.
649 * Returns: Returns 0 on success or negative error code on failure.
650 */
hte_request_ts_ns(struct hte_ts_desc * desc,hte_ts_cb_t cb,hte_ts_sec_cb_t tcb,void * data)651 int hte_request_ts_ns(struct hte_ts_desc *desc, hte_ts_cb_t cb,
652 hte_ts_sec_cb_t tcb, void *data)
653 {
654 int ret;
655 struct hte_ts_info *ei;
656
657 if (!desc || !desc->hte_data || !cb)
658 return -EINVAL;
659
660 ei = desc->hte_data;
661 if (!ei || !ei->gdev)
662 return -EINVAL;
663
664 ret = __hte_req_ts(desc, cb, tcb, data);
665 if (ret < 0) {
666 dev_err(ei->gdev->chip->dev,
667 "failed to request id: %d\n", desc->attr.line_id);
668 return ret;
669 }
670
671 return 0;
672 }
673 EXPORT_SYMBOL_GPL(hte_request_ts_ns);
674
675 /**
676 * devm_hte_request_ts_ns() - Resource managed API to request and enable
677 * hardware timestamp in nanoseconds.
678 *
679 * The entity is provider specific for example, GPIO lines, signals, buses
680 * etc...The API allocates necessary resources and enables the timestamp. It
681 * deallocates and disables automatically when the consumer exits.
682 *
683 * @dev: HTE consumer/client device.
684 * @desc: Pre-allocated and initialized timestamp descriptor.
685 * @cb: Callback to push the timestamp data to consumer.
686 * @tcb: Optional callback. If its provided, subsystem initializes
687 * workqueue. It is called when cb returns HTE_RUN_SECOND_CB.
688 * @data: Client data, used during cb and tcb callbacks.
689 *
690 * Context: Holds mutex lock.
691 * Returns: Returns 0 on success or negative error code on failure.
692 */
devm_hte_request_ts_ns(struct device * dev,struct hte_ts_desc * desc,hte_ts_cb_t cb,hte_ts_sec_cb_t tcb,void * data)693 int devm_hte_request_ts_ns(struct device *dev, struct hte_ts_desc *desc,
694 hte_ts_cb_t cb, hte_ts_sec_cb_t tcb,
695 void *data)
696 {
697 int err;
698
699 if (!dev)
700 return -EINVAL;
701
702 err = hte_request_ts_ns(desc, cb, tcb, data);
703 if (err)
704 return err;
705
706 err = devm_add_action_or_reset(dev, __devm_hte_release_ts, desc);
707 if (err)
708 return err;
709
710 return 0;
711 }
712 EXPORT_SYMBOL_GPL(devm_hte_request_ts_ns);
713
714 /**
715 * hte_init_line_attr() - Initialize line attributes.
716 *
717 * Zeroes out line attributes and initializes with provided arguments.
718 * The function needs to be called before calling any consumer facing
719 * functions.
720 *
721 * @desc: Pre-allocated timestamp descriptor.
722 * @line_id: line id.
723 * @edge_flags: edge flags related to line_id.
724 * @name: name of the line.
725 * @data: line data related to line_id.
726 *
727 * Context: Any.
728 * Returns: 0 on success or negative error code for the failure.
729 */
hte_init_line_attr(struct hte_ts_desc * desc,u32 line_id,unsigned long edge_flags,const char * name,void * data)730 int hte_init_line_attr(struct hte_ts_desc *desc, u32 line_id,
731 unsigned long edge_flags, const char *name, void *data)
732 {
733 if (!desc)
734 return -EINVAL;
735
736 memset(&desc->attr, 0, sizeof(desc->attr));
737
738 desc->attr.edge_flags = edge_flags;
739 desc->attr.line_id = line_id;
740 desc->attr.line_data = data;
741 if (name) {
742 name = kstrdup_const(name, GFP_KERNEL);
743 if (!name)
744 return -ENOMEM;
745 }
746
747 desc->attr.name = name;
748
749 return 0;
750 }
751 EXPORT_SYMBOL_GPL(hte_init_line_attr);
752
753 /**
754 * hte_get_clk_src_info() - Get the clock source information for a ts
755 * descriptor.
756 *
757 * @desc: ts descriptor, same as returned from request API.
758 * @ci: The API fills this structure with the clock information data.
759 *
760 * Context: Any context.
761 * Returns: 0 on success else negative error code on failure.
762 */
hte_get_clk_src_info(const struct hte_ts_desc * desc,struct hte_clk_info * ci)763 int hte_get_clk_src_info(const struct hte_ts_desc *desc,
764 struct hte_clk_info *ci)
765 {
766 struct hte_chip *chip;
767 struct hte_ts_info *ei;
768
769 if (!desc || !desc->hte_data || !ci) {
770 pr_debug("%s:%d\n", __func__, __LINE__);
771 return -EINVAL;
772 }
773
774 ei = desc->hte_data;
775 if (!ei->gdev || !ei->gdev->chip)
776 return -EINVAL;
777
778 chip = ei->gdev->chip;
779 if (!chip->ops->get_clk_src_info)
780 return -EOPNOTSUPP;
781
782 return chip->ops->get_clk_src_info(chip, ci);
783 }
784 EXPORT_SYMBOL_GPL(hte_get_clk_src_info);
785
786 /**
787 * hte_push_ts_ns() - Push timestamp data in nanoseconds.
788 *
789 * It is used by the provider to push timestamp data.
790 *
791 * @chip: The HTE chip, used during the registration.
792 * @xlated_id: entity id understood by both subsystem and provider, this is
793 * obtained from xlate callback during request API.
794 * @data: timestamp data.
795 *
796 * Returns: 0 on success or a negative error code on failure.
797 */
hte_push_ts_ns(const struct hte_chip * chip,u32 xlated_id,struct hte_ts_data * data)798 int hte_push_ts_ns(const struct hte_chip *chip, u32 xlated_id,
799 struct hte_ts_data *data)
800 {
801 enum hte_return ret;
802 int st = 0;
803 struct hte_ts_info *ei;
804 unsigned long flag;
805
806 if (!chip || !data || !chip->gdev)
807 return -EINVAL;
808
809 if (xlated_id >= chip->nlines)
810 return -EINVAL;
811
812 ei = &chip->gdev->ei[xlated_id];
813
814 spin_lock_irqsave(&ei->slock, flag);
815
816 /* timestamp sequence counter */
817 data->seq = ei->seq++;
818
819 if (!test_bit(HTE_TS_REGISTERED, &ei->flags) ||
820 test_bit(HTE_TS_DISABLE, &ei->flags)) {
821 dev_dbg(chip->dev, "Unknown timestamp push\n");
822 atomic_inc(&ei->dropped_ts);
823 st = -EINVAL;
824 goto unlock;
825 }
826
827 ret = ei->cb(data, ei->cl_data);
828 if (ret == HTE_RUN_SECOND_CB && ei->tcb) {
829 queue_work(system_unbound_wq, &ei->cb_work);
830 set_bit(HTE_TS_QUEUE_WK, &ei->flags);
831 }
832
833 unlock:
834 spin_unlock_irqrestore(&ei->slock, flag);
835
836 return st;
837 }
838 EXPORT_SYMBOL_GPL(hte_push_ts_ns);
839
hte_register_chip(struct hte_chip * chip)840 static int hte_register_chip(struct hte_chip *chip)
841 {
842 struct hte_device *gdev;
843 u32 i;
844
845 if (!chip || !chip->dev || !chip->dev->of_node)
846 return -EINVAL;
847
848 if (!chip->ops || !chip->ops->request || !chip->ops->release) {
849 dev_err(chip->dev, "Driver needs to provide ops\n");
850 return -EINVAL;
851 }
852
853 gdev = kzalloc(struct_size(gdev, ei, chip->nlines), GFP_KERNEL);
854 if (!gdev)
855 return -ENOMEM;
856
857 gdev->chip = chip;
858 chip->gdev = gdev;
859 gdev->nlines = chip->nlines;
860 gdev->sdev = chip->dev;
861
862 for (i = 0; i < chip->nlines; i++) {
863 gdev->ei[i].gdev = gdev;
864 mutex_init(&gdev->ei[i].req_mlock);
865 spin_lock_init(&gdev->ei[i].slock);
866 }
867
868 if (chip->dev->driver)
869 gdev->owner = chip->dev->driver->owner;
870 else
871 gdev->owner = THIS_MODULE;
872
873 of_node_get(chip->dev->of_node);
874
875 INIT_LIST_HEAD(&gdev->list);
876
877 spin_lock(&hte_lock);
878 list_add_tail(&gdev->list, &hte_devices);
879 spin_unlock(&hte_lock);
880
881 hte_chip_dbgfs_init(gdev);
882
883 dev_dbg(chip->dev, "Added hte chip\n");
884
885 return 0;
886 }
887
hte_unregister_chip(struct hte_chip * chip)888 static int hte_unregister_chip(struct hte_chip *chip)
889 {
890 struct hte_device *gdev;
891
892 if (!chip)
893 return -EINVAL;
894
895 gdev = chip->gdev;
896
897 spin_lock(&hte_lock);
898 list_del(&gdev->list);
899 spin_unlock(&hte_lock);
900
901 gdev->chip = NULL;
902
903 of_node_put(chip->dev->of_node);
904 debugfs_remove_recursive(gdev->dbg_root);
905 kfree(gdev);
906
907 dev_dbg(chip->dev, "Removed hte chip\n");
908
909 return 0;
910 }
911
_hte_devm_unregister_chip(void * chip)912 static void _hte_devm_unregister_chip(void *chip)
913 {
914 hte_unregister_chip(chip);
915 }
916
917 /**
918 * devm_hte_register_chip() - Resource managed API to register HTE chip.
919 *
920 * It is used by the provider to register itself with the HTE subsystem.
921 * The unregistration is done automatically when the provider exits.
922 *
923 * @chip: the HTE chip to add to subsystem.
924 *
925 * Returns: 0 on success or a negative error code on failure.
926 */
devm_hte_register_chip(struct hte_chip * chip)927 int devm_hte_register_chip(struct hte_chip *chip)
928 {
929 int err;
930
931 err = hte_register_chip(chip);
932 if (err)
933 return err;
934
935 err = devm_add_action_or_reset(chip->dev, _hte_devm_unregister_chip,
936 chip);
937 if (err)
938 return err;
939
940 return 0;
941 }
942 EXPORT_SYMBOL_GPL(devm_hte_register_chip);
943