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20#include <linux/idr.h>
21#include <linux/device.h>
22#include <linux/err.h>
23#include <linux/init.h>
24#include <linux/kernel.h>
25#include <linux/module.h>
26#include <linux/posix-clock.h>
27#include <linux/pps_kernel.h>
28#include <linux/slab.h>
29#include <linux/syscalls.h>
30#include <linux/uaccess.h>
31#include <uapi/linux/sched/types.h>
32
33#include "ptp_private.h"
34
35#define PTP_MAX_ALARMS 4
36#define PTP_PPS_DEFAULTS (PPS_CAPTUREASSERT | PPS_OFFSETASSERT)
37#define PTP_PPS_EVENT PPS_CAPTUREASSERT
38#define PTP_PPS_MODE (PTP_PPS_DEFAULTS | PPS_CANWAIT | PPS_TSFMT_TSPEC)
39
40
41
42static dev_t ptp_devt;
43static struct class *ptp_class;
44
45static DEFINE_IDA(ptp_clocks_map);
46
47
48
49static inline int queue_free(struct timestamp_event_queue *q)
50{
51 return PTP_MAX_TIMESTAMPS - queue_cnt(q) - 1;
52}
53
54static void enqueue_external_timestamp(struct timestamp_event_queue *queue,
55 struct ptp_clock_event *src)
56{
57 struct ptp_extts_event *dst;
58 unsigned long flags;
59 s64 seconds;
60 u32 remainder;
61
62 seconds = div_u64_rem(src->timestamp, 1000000000, &remainder);
63
64 spin_lock_irqsave(&queue->lock, flags);
65
66 dst = &queue->buf[queue->tail];
67 dst->index = src->index;
68 dst->t.sec = seconds;
69 dst->t.nsec = remainder;
70
71 if (!queue_free(queue))
72 queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
73
74 queue->tail = (queue->tail + 1) % PTP_MAX_TIMESTAMPS;
75
76 spin_unlock_irqrestore(&queue->lock, flags);
77}
78
79static s32 scaled_ppm_to_ppb(long ppm)
80{
81
82
83
84
85
86
87
88
89
90
91
92
93 s64 ppb = 1 + ppm;
94 ppb *= 125;
95 ppb >>= 13;
96 return (s32) ppb;
97}
98
99
100
101static int ptp_clock_getres(struct posix_clock *pc, struct timespec64 *tp)
102{
103 tp->tv_sec = 0;
104 tp->tv_nsec = 1;
105 return 0;
106}
107
108static int ptp_clock_settime(struct posix_clock *pc, const struct timespec64 *tp)
109{
110 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
111
112 return ptp->info->settime64(ptp->info, tp);
113}
114
115static int ptp_clock_gettime(struct posix_clock *pc, struct timespec64 *tp)
116{
117 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
118 int err;
119
120 err = ptp->info->gettime64(ptp->info, tp);
121 return err;
122}
123
124static int ptp_clock_adjtime(struct posix_clock *pc, struct timex *tx)
125{
126 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
127 struct ptp_clock_info *ops;
128 int err = -EOPNOTSUPP;
129
130 ops = ptp->info;
131
132 if (tx->modes & ADJ_SETOFFSET) {
133 struct timespec64 ts;
134 ktime_t kt;
135 s64 delta;
136
137 ts.tv_sec = tx->time.tv_sec;
138 ts.tv_nsec = tx->time.tv_usec;
139
140 if (!(tx->modes & ADJ_NANO))
141 ts.tv_nsec *= 1000;
142
143 if ((unsigned long) ts.tv_nsec >= NSEC_PER_SEC)
144 return -EINVAL;
145
146 kt = timespec64_to_ktime(ts);
147 delta = ktime_to_ns(kt);
148 err = ops->adjtime(ops, delta);
149 } else if (tx->modes & ADJ_FREQUENCY) {
150 s32 ppb = scaled_ppm_to_ppb(tx->freq);
151 if (ppb > ops->max_adj || ppb < -ops->max_adj)
152 return -ERANGE;
153 if (ops->adjfine)
154 err = ops->adjfine(ops, tx->freq);
155 else
156 err = ops->adjfreq(ops, ppb);
157 ptp->dialed_frequency = tx->freq;
158 } else if (tx->modes == 0) {
159 tx->freq = ptp->dialed_frequency;
160 err = 0;
161 }
162
163 return err;
164}
165
166static struct posix_clock_operations ptp_clock_ops = {
167 .owner = THIS_MODULE,
168 .clock_adjtime = ptp_clock_adjtime,
169 .clock_gettime = ptp_clock_gettime,
170 .clock_getres = ptp_clock_getres,
171 .clock_settime = ptp_clock_settime,
172 .ioctl = ptp_ioctl,
173 .open = ptp_open,
174 .poll = ptp_poll,
175 .read = ptp_read,
176};
177
178static void delete_ptp_clock(struct posix_clock *pc)
179{
180 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
181
182 mutex_destroy(&ptp->tsevq_mux);
183 mutex_destroy(&ptp->pincfg_mux);
184 ida_simple_remove(&ptp_clocks_map, ptp->index);
185 kfree(ptp);
186}
187
188static void ptp_aux_kworker(struct kthread_work *work)
189{
190 struct ptp_clock *ptp = container_of(work, struct ptp_clock,
191 aux_work.work);
192 struct ptp_clock_info *info = ptp->info;
193 long delay;
194
195 delay = info->do_aux_work(info);
196
197 if (delay >= 0)
198 kthread_queue_delayed_work(ptp->kworker, &ptp->aux_work, delay);
199}
200
201
202
203struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
204 struct device *parent)
205{
206 struct ptp_clock *ptp;
207 int err = 0, index, major = MAJOR(ptp_devt);
208
209 if (info->n_alarm > PTP_MAX_ALARMS)
210 return ERR_PTR(-EINVAL);
211
212
213 err = -ENOMEM;
214 ptp = kzalloc(sizeof(struct ptp_clock), GFP_KERNEL);
215 if (ptp == NULL)
216 goto no_memory;
217
218 index = ida_simple_get(&ptp_clocks_map, 0, MINORMASK + 1, GFP_KERNEL);
219 if (index < 0) {
220 err = index;
221 goto no_slot;
222 }
223
224 ptp->clock.ops = ptp_clock_ops;
225 ptp->clock.release = delete_ptp_clock;
226 ptp->info = info;
227 ptp->devid = MKDEV(major, index);
228 ptp->index = index;
229 spin_lock_init(&ptp->tsevq.lock);
230 mutex_init(&ptp->tsevq_mux);
231 mutex_init(&ptp->pincfg_mux);
232 init_waitqueue_head(&ptp->tsev_wq);
233
234 if (ptp->info->do_aux_work) {
235 char *worker_name = kasprintf(GFP_KERNEL, "ptp%d", ptp->index);
236
237 kthread_init_delayed_work(&ptp->aux_work, ptp_aux_kworker);
238 ptp->kworker = kthread_create_worker(0, worker_name ?
239 worker_name : info->name);
240 kfree(worker_name);
241 if (IS_ERR(ptp->kworker)) {
242 err = PTR_ERR(ptp->kworker);
243 pr_err("failed to create ptp aux_worker %d\n", err);
244 goto kworker_err;
245 }
246 }
247
248 err = ptp_populate_pin_groups(ptp);
249 if (err)
250 goto no_pin_groups;
251
252
253 ptp->dev = device_create_with_groups(ptp_class, parent, ptp->devid,
254 ptp, ptp->pin_attr_groups,
255 "ptp%d", ptp->index);
256 if (IS_ERR(ptp->dev))
257 goto no_device;
258
259
260 if (info->pps) {
261 struct pps_source_info pps;
262 memset(&pps, 0, sizeof(pps));
263 snprintf(pps.name, PPS_MAX_NAME_LEN, "ptp%d", index);
264 pps.mode = PTP_PPS_MODE;
265 pps.owner = info->owner;
266 ptp->pps_source = pps_register_source(&pps, PTP_PPS_DEFAULTS);
267 if (!ptp->pps_source) {
268 pr_err("failed to register pps source\n");
269 goto no_pps;
270 }
271 }
272
273
274 err = posix_clock_register(&ptp->clock, ptp->devid);
275 if (err) {
276 pr_err("failed to create posix clock\n");
277 goto no_clock;
278 }
279
280 return ptp;
281
282no_clock:
283 if (ptp->pps_source)
284 pps_unregister_source(ptp->pps_source);
285no_pps:
286 device_destroy(ptp_class, ptp->devid);
287no_device:
288 ptp_cleanup_pin_groups(ptp);
289no_pin_groups:
290 if (ptp->kworker)
291 kthread_destroy_worker(ptp->kworker);
292kworker_err:
293 mutex_destroy(&ptp->tsevq_mux);
294 mutex_destroy(&ptp->pincfg_mux);
295 ida_simple_remove(&ptp_clocks_map, index);
296no_slot:
297 kfree(ptp);
298no_memory:
299 return ERR_PTR(err);
300}
301EXPORT_SYMBOL(ptp_clock_register);
302
303int ptp_clock_unregister(struct ptp_clock *ptp)
304{
305 ptp->defunct = 1;
306 wake_up_interruptible(&ptp->tsev_wq);
307
308 if (ptp->kworker) {
309 kthread_cancel_delayed_work_sync(&ptp->aux_work);
310 kthread_destroy_worker(ptp->kworker);
311 }
312
313
314 if (ptp->pps_source)
315 pps_unregister_source(ptp->pps_source);
316
317 device_destroy(ptp_class, ptp->devid);
318 ptp_cleanup_pin_groups(ptp);
319
320 posix_clock_unregister(&ptp->clock);
321 return 0;
322}
323EXPORT_SYMBOL(ptp_clock_unregister);
324
325void ptp_clock_event(struct ptp_clock *ptp, struct ptp_clock_event *event)
326{
327 struct pps_event_time evt;
328
329 switch (event->type) {
330
331 case PTP_CLOCK_ALARM:
332 break;
333
334 case PTP_CLOCK_EXTTS:
335 enqueue_external_timestamp(&ptp->tsevq, event);
336 wake_up_interruptible(&ptp->tsev_wq);
337 break;
338
339 case PTP_CLOCK_PPS:
340 pps_get_ts(&evt);
341 pps_event(ptp->pps_source, &evt, PTP_PPS_EVENT, NULL);
342 break;
343
344 case PTP_CLOCK_PPSUSR:
345 pps_event(ptp->pps_source, &event->pps_times,
346 PTP_PPS_EVENT, NULL);
347 break;
348 }
349}
350EXPORT_SYMBOL(ptp_clock_event);
351
352int ptp_clock_index(struct ptp_clock *ptp)
353{
354 return ptp->index;
355}
356EXPORT_SYMBOL(ptp_clock_index);
357
358int ptp_find_pin(struct ptp_clock *ptp,
359 enum ptp_pin_function func, unsigned int chan)
360{
361 struct ptp_pin_desc *pin = NULL;
362 int i;
363
364 mutex_lock(&ptp->pincfg_mux);
365 for (i = 0; i < ptp->info->n_pins; i++) {
366 if (ptp->info->pin_config[i].func == func &&
367 ptp->info->pin_config[i].chan == chan) {
368 pin = &ptp->info->pin_config[i];
369 break;
370 }
371 }
372 mutex_unlock(&ptp->pincfg_mux);
373
374 return pin ? i : -1;
375}
376EXPORT_SYMBOL(ptp_find_pin);
377
378int ptp_schedule_worker(struct ptp_clock *ptp, unsigned long delay)
379{
380 return kthread_mod_delayed_work(ptp->kworker, &ptp->aux_work, delay);
381}
382EXPORT_SYMBOL(ptp_schedule_worker);
383
384
385
386static void __exit ptp_exit(void)
387{
388 class_destroy(ptp_class);
389 unregister_chrdev_region(ptp_devt, MINORMASK + 1);
390 ida_destroy(&ptp_clocks_map);
391}
392
393static int __init ptp_init(void)
394{
395 int err;
396
397 ptp_class = class_create(THIS_MODULE, "ptp");
398 if (IS_ERR(ptp_class)) {
399 pr_err("ptp: failed to allocate class\n");
400 return PTR_ERR(ptp_class);
401 }
402
403 err = alloc_chrdev_region(&ptp_devt, 0, MINORMASK + 1, "ptp");
404 if (err < 0) {
405 pr_err("ptp: failed to allocate device region\n");
406 goto no_region;
407 }
408
409 ptp_class->dev_groups = ptp_groups;
410 pr_info("PTP clock support registered\n");
411 return 0;
412
413no_region:
414 class_destroy(ptp_class);
415 return err;
416}
417
418subsys_initcall(ptp_init);
419module_exit(ptp_exit);
420
421MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
422MODULE_DESCRIPTION("PTP clocks support");
423MODULE_LICENSE("GPL");
424
