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1/*
2 * PTP 1588 clock support
3 *
4 * Copyright (C) 2010 OMICRON electronics GmbH
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
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
32#include "ptp_private.h"
33
34#define PTP_MAX_ALARMS 4
35#define PTP_PPS_DEFAULTS (PPS_CAPTUREASSERT | PPS_OFFSETASSERT)
36#define PTP_PPS_EVENT PPS_CAPTUREASSERT
37#define PTP_PPS_MODE (PTP_PPS_DEFAULTS | PPS_CANWAIT | PPS_TSFMT_TSPEC)
38
39/* private globals */
40
41static dev_t ptp_devt;
42static struct class *ptp_class;
43
44static DEFINE_IDA(ptp_clocks_map);
45
46/* time stamp event queue operations */
47
48static inline int queue_free(struct timestamp_event_queue *q)
49{
50 return PTP_MAX_TIMESTAMPS - queue_cnt(q) - 1;
51}
52
53static void enqueue_external_timestamp(struct timestamp_event_queue *queue,
54 struct ptp_clock_event *src)
55{
56 struct ptp_extts_event *dst;
57 unsigned long flags;
58 s64 seconds;
59 u32 remainder;
60
61 seconds = div_u64_rem(src->timestamp, 1000000000, &remainder);
62
63 spin_lock_irqsave(&queue->lock, flags);
64
65 dst = &queue->buf[queue->tail];
66 dst->index = src->index;
67 dst->t.sec = seconds;
68 dst->t.nsec = remainder;
69
70 if (!queue_free(queue))
71 queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
72
73 queue->tail = (queue->tail + 1) % PTP_MAX_TIMESTAMPS;
74
75 spin_unlock_irqrestore(&queue->lock, flags);
76}
77
78static s32 scaled_ppm_to_ppb(long ppm)
79{
80 /*
81 * The 'freq' field in the 'struct timex' is in parts per
82 * million, but with a 16 bit binary fractional field.
83 *
84 * We want to calculate
85 *
86 * ppb = scaled_ppm * 1000 / 2^16
87 *
88 * which simplifies to
89 *
90 * ppb = scaled_ppm * 125 / 2^13
91 */
92 s64 ppb = 1 + ppm;
93 ppb *= 125;
94 ppb >>= 13;
95 return (s32) ppb;
96}
97
98/* posix clock implementation */
99
100static int ptp_clock_getres(struct posix_clock *pc, struct timespec *tp)
101{
102 tp->tv_sec = 0;
103 tp->tv_nsec = 1;
104 return 0;
105}
106
107static int ptp_clock_settime(struct posix_clock *pc, const struct timespec *tp)
108{
109 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
110 return ptp->info->settime(ptp->info, tp);
111}
112
113static int ptp_clock_gettime(struct posix_clock *pc, struct timespec *tp)
114{
115 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
116 return ptp->info->gettime(ptp->info, tp);
117}
118
119static int ptp_clock_adjtime(struct posix_clock *pc, struct timex *tx)
120{
121 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
122 struct ptp_clock_info *ops;
123 int err = -EOPNOTSUPP;
124
125 ops = ptp->info;
126
127 if (tx->modes & ADJ_SETOFFSET) {
128 struct timespec ts;
129 ktime_t kt;
130 s64 delta;
131
132 ts.tv_sec = tx->time.tv_sec;
133 ts.tv_nsec = tx->time.tv_usec;
134
135 if (!(tx->modes & ADJ_NANO))
136 ts.tv_nsec *= 1000;
137
138 if ((unsigned long) ts.tv_nsec >= NSEC_PER_SEC)
139 return -EINVAL;
140
141 kt = timespec_to_ktime(ts);
142 delta = ktime_to_ns(kt);
143 err = ops->adjtime(ops, delta);
144 } else if (tx->modes & ADJ_FREQUENCY) {
145 err = ops->adjfreq(ops, scaled_ppm_to_ppb(tx->freq));
146 ptp->dialed_frequency = tx->freq;
147 } else if (tx->modes == 0) {
148 tx->freq = ptp->dialed_frequency;
149 err = 0;
150 }
151
152 return err;
153}
154
155static struct posix_clock_operations ptp_clock_ops = {
156 .owner = THIS_MODULE,
157 .clock_adjtime = ptp_clock_adjtime,
158 .clock_gettime = ptp_clock_gettime,
159 .clock_getres = ptp_clock_getres,
160 .clock_settime = ptp_clock_settime,
161 .ioctl = ptp_ioctl,
162 .open = ptp_open,
163 .poll = ptp_poll,
164 .read = ptp_read,
165};
166
167static void delete_ptp_clock(struct posix_clock *pc)
168{
169 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
170
171 mutex_destroy(&ptp->tsevq_mux);
172 mutex_destroy(&ptp->pincfg_mux);
173 ida_simple_remove(&ptp_clocks_map, ptp->index);
174 kfree(ptp);
175}
176
177/* public interface */
178
179struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
180 struct device *parent)
181{
182 struct ptp_clock *ptp;
183 int err = 0, index, major = MAJOR(ptp_devt);
184
185 if (info->n_alarm > PTP_MAX_ALARMS)
186 return ERR_PTR(-EINVAL);
187
188 /* Initialize a clock structure. */
189 err = -ENOMEM;
190 ptp = kzalloc(sizeof(struct ptp_clock), GFP_KERNEL);
191 if (ptp == NULL)
192 goto no_memory;
193
194 index = ida_simple_get(&ptp_clocks_map, 0, MINORMASK + 1, GFP_KERNEL);
195 if (index < 0) {
196 err = index;
197 goto no_slot;
198 }
199
200 ptp->clock.ops = ptp_clock_ops;
201 ptp->clock.release = delete_ptp_clock;
202 ptp->info = info;
203 ptp->devid = MKDEV(major, index);
204 ptp->index = index;
205 spin_lock_init(&ptp->tsevq.lock);
206 mutex_init(&ptp->tsevq_mux);
207 mutex_init(&ptp->pincfg_mux);
208 init_waitqueue_head(&ptp->tsev_wq);
209
210 /* Create a new device in our class. */
211 ptp->dev = device_create(ptp_class, parent, ptp->devid, ptp,
212 "ptp%d", ptp->index);
213 if (IS_ERR(ptp->dev))
214 goto no_device;
215
216 dev_set_drvdata(ptp->dev, ptp);
217
218 err = ptp_populate_sysfs(ptp);
219 if (err)
220 goto no_sysfs;
221
222 /* Register a new PPS source. */
223 if (info->pps) {
224 struct pps_source_info pps;
225 memset(&pps, 0, sizeof(pps));
226 snprintf(pps.name, PPS_MAX_NAME_LEN, "ptp%d", index);
227 pps.mode = PTP_PPS_MODE;
228 pps.owner = info->owner;
229 ptp->pps_source = pps_register_source(&pps, PTP_PPS_DEFAULTS);
230 if (!ptp->pps_source) {
231 pr_err("failed to register pps source\n");
232 goto no_pps;
233 }
234 }
235
236 /* Create a posix clock. */
237 err = posix_clock_register(&ptp->clock, ptp->devid);
238 if (err) {
239 pr_err("failed to create posix clock\n");
240 goto no_clock;
241 }
242
243 return ptp;
244
245no_clock:
246 if (ptp->pps_source)
247 pps_unregister_source(ptp->pps_source);
248no_pps:
249 ptp_cleanup_sysfs(ptp);
250no_sysfs:
251 device_destroy(ptp_class, ptp->devid);
252no_device:
253 mutex_destroy(&ptp->tsevq_mux);
254 mutex_destroy(&ptp->pincfg_mux);
255no_slot:
256 kfree(ptp);
257no_memory:
258 return ERR_PTR(err);
259}
260EXPORT_SYMBOL(ptp_clock_register);
261
262int ptp_clock_unregister(struct ptp_clock *ptp)
263{
264 ptp->defunct = 1;
265 wake_up_interruptible(&ptp->tsev_wq);
266
267 /* Release the clock's resources. */
268 if (ptp->pps_source)
269 pps_unregister_source(ptp->pps_source);
270 ptp_cleanup_sysfs(ptp);
271 device_destroy(ptp_class, ptp->devid);
272
273 posix_clock_unregister(&ptp->clock);
274 return 0;
275}
276EXPORT_SYMBOL(ptp_clock_unregister);
277
278void ptp_clock_event(struct ptp_clock *ptp, struct ptp_clock_event *event)
279{
280 struct pps_event_time evt;
281
282 switch (event->type) {
283
284 case PTP_CLOCK_ALARM:
285 break;
286
287 case PTP_CLOCK_EXTTS:
288 enqueue_external_timestamp(&ptp->tsevq, event);
289 wake_up_interruptible(&ptp->tsev_wq);
290 break;
291
292 case PTP_CLOCK_PPS:
293 pps_get_ts(&evt);
294 pps_event(ptp->pps_source, &evt, PTP_PPS_EVENT, NULL);
295 break;
296
297 case PTP_CLOCK_PPSUSR:
298 pps_event(ptp->pps_source, &event->pps_times,
299 PTP_PPS_EVENT, NULL);
300 break;
301 }
302}
303EXPORT_SYMBOL(ptp_clock_event);
304
305int ptp_clock_index(struct ptp_clock *ptp)
306{
307 return ptp->index;
308}
309EXPORT_SYMBOL(ptp_clock_index);
310
311int ptp_find_pin(struct ptp_clock *ptp,
312 enum ptp_pin_function func, unsigned int chan)
313{
314 struct ptp_pin_desc *pin = NULL;
315 int i;
316
317 mutex_lock(&ptp->pincfg_mux);
318 for (i = 0; i < ptp->info->n_pins; i++) {
319 if (ptp->info->pin_config[i].func == func &&
320 ptp->info->pin_config[i].chan == chan) {
321 pin = &ptp->info->pin_config[i];
322 break;
323 }
324 }
325 mutex_unlock(&ptp->pincfg_mux);
326
327 return pin ? i : -1;
328}
329EXPORT_SYMBOL(ptp_find_pin);
330
331/* module operations */
332
333static void __exit ptp_exit(void)
334{
335 class_destroy(ptp_class);
336 unregister_chrdev_region(ptp_devt, MINORMASK + 1);
337 ida_destroy(&ptp_clocks_map);
338}
339
340static int __init ptp_init(void)
341{
342 int err;
343
344 ptp_class = class_create(THIS_MODULE, "ptp");
345 if (IS_ERR(ptp_class)) {
346 pr_err("ptp: failed to allocate class\n");
347 return PTR_ERR(ptp_class);
348 }
349
350 err = alloc_chrdev_region(&ptp_devt, 0, MINORMASK + 1, "ptp");
351 if (err < 0) {
352 pr_err("ptp: failed to allocate device region\n");
353 goto no_region;
354 }
355
356 ptp_class->dev_groups = ptp_groups;
357 pr_info("PTP clock support registered\n");
358 return 0;
359
360no_region:
361 class_destroy(ptp_class);
362 return err;
363}
364
365subsys_initcall(ptp_init);
366module_exit(ptp_exit);
367
368MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
369MODULE_DESCRIPTION("PTP clocks support");
370MODULE_LICENSE("GPL");
1/*
2 * PTP 1588 clock support
3 *
4 * Copyright (C) 2010 OMICRON electronics GmbH
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
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
32#include "ptp_private.h"
33
34#define PTP_MAX_ALARMS 4
35#define PTP_PPS_DEFAULTS (PPS_CAPTUREASSERT | PPS_OFFSETASSERT)
36#define PTP_PPS_EVENT PPS_CAPTUREASSERT
37#define PTP_PPS_MODE (PTP_PPS_DEFAULTS | PPS_CANWAIT | PPS_TSFMT_TSPEC)
38
39/* private globals */
40
41static dev_t ptp_devt;
42static struct class *ptp_class;
43
44static DEFINE_IDA(ptp_clocks_map);
45
46/* time stamp event queue operations */
47
48static inline int queue_free(struct timestamp_event_queue *q)
49{
50 return PTP_MAX_TIMESTAMPS - queue_cnt(q) - 1;
51}
52
53static void enqueue_external_timestamp(struct timestamp_event_queue *queue,
54 struct ptp_clock_event *src)
55{
56 struct ptp_extts_event *dst;
57 unsigned long flags;
58 s64 seconds;
59 u32 remainder;
60
61 seconds = div_u64_rem(src->timestamp, 1000000000, &remainder);
62
63 spin_lock_irqsave(&queue->lock, flags);
64
65 dst = &queue->buf[queue->tail];
66 dst->index = src->index;
67 dst->t.sec = seconds;
68 dst->t.nsec = remainder;
69
70 if (!queue_free(queue))
71 queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
72
73 queue->tail = (queue->tail + 1) % PTP_MAX_TIMESTAMPS;
74
75 spin_unlock_irqrestore(&queue->lock, flags);
76}
77
78static s32 scaled_ppm_to_ppb(long ppm)
79{
80 /*
81 * The 'freq' field in the 'struct timex' is in parts per
82 * million, but with a 16 bit binary fractional field.
83 *
84 * We want to calculate
85 *
86 * ppb = scaled_ppm * 1000 / 2^16
87 *
88 * which simplifies to
89 *
90 * ppb = scaled_ppm * 125 / 2^13
91 */
92 s64 ppb = 1 + ppm;
93 ppb *= 125;
94 ppb >>= 13;
95 return (s32) ppb;
96}
97
98/* posix clock implementation */
99
100static int ptp_clock_getres(struct posix_clock *pc, struct timespec *tp)
101{
102 tp->tv_sec = 0;
103 tp->tv_nsec = 1;
104 return 0;
105}
106
107static int ptp_clock_settime(struct posix_clock *pc, const struct timespec *tp)
108{
109 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
110 struct timespec64 ts = timespec_to_timespec64(*tp);
111
112 return ptp->info->settime64(ptp->info, &ts);
113}
114
115static int ptp_clock_gettime(struct posix_clock *pc, struct timespec *tp)
116{
117 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
118 struct timespec64 ts;
119 int err;
120
121 err = ptp->info->gettime64(ptp->info, &ts);
122 if (!err)
123 *tp = timespec64_to_timespec(ts);
124 return err;
125}
126
127static int ptp_clock_adjtime(struct posix_clock *pc, struct timex *tx)
128{
129 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
130 struct ptp_clock_info *ops;
131 int err = -EOPNOTSUPP;
132
133 ops = ptp->info;
134
135 if (tx->modes & ADJ_SETOFFSET) {
136 struct timespec ts;
137 ktime_t kt;
138 s64 delta;
139
140 ts.tv_sec = tx->time.tv_sec;
141 ts.tv_nsec = tx->time.tv_usec;
142
143 if (!(tx->modes & ADJ_NANO))
144 ts.tv_nsec *= 1000;
145
146 if ((unsigned long) ts.tv_nsec >= NSEC_PER_SEC)
147 return -EINVAL;
148
149 kt = timespec_to_ktime(ts);
150 delta = ktime_to_ns(kt);
151 err = ops->adjtime(ops, delta);
152 } else if (tx->modes & ADJ_FREQUENCY) {
153 s32 ppb = scaled_ppm_to_ppb(tx->freq);
154 if (ppb > ops->max_adj || ppb < -ops->max_adj)
155 return -ERANGE;
156 if (ops->adjfine)
157 err = ops->adjfine(ops, tx->freq);
158 else
159 err = ops->adjfreq(ops, ppb);
160 ptp->dialed_frequency = tx->freq;
161 } else if (tx->modes == 0) {
162 tx->freq = ptp->dialed_frequency;
163 err = 0;
164 }
165
166 return err;
167}
168
169static struct posix_clock_operations ptp_clock_ops = {
170 .owner = THIS_MODULE,
171 .clock_adjtime = ptp_clock_adjtime,
172 .clock_gettime = ptp_clock_gettime,
173 .clock_getres = ptp_clock_getres,
174 .clock_settime = ptp_clock_settime,
175 .ioctl = ptp_ioctl,
176 .open = ptp_open,
177 .poll = ptp_poll,
178 .read = ptp_read,
179};
180
181static void delete_ptp_clock(struct posix_clock *pc)
182{
183 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
184
185 mutex_destroy(&ptp->tsevq_mux);
186 mutex_destroy(&ptp->pincfg_mux);
187 ida_simple_remove(&ptp_clocks_map, ptp->index);
188 kfree(ptp);
189}
190
191/* public interface */
192
193struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
194 struct device *parent)
195{
196 struct ptp_clock *ptp;
197 int err = 0, index, major = MAJOR(ptp_devt);
198
199 if (info->n_alarm > PTP_MAX_ALARMS)
200 return ERR_PTR(-EINVAL);
201
202 /* Initialize a clock structure. */
203 err = -ENOMEM;
204 ptp = kzalloc(sizeof(struct ptp_clock), GFP_KERNEL);
205 if (ptp == NULL)
206 goto no_memory;
207
208 index = ida_simple_get(&ptp_clocks_map, 0, MINORMASK + 1, GFP_KERNEL);
209 if (index < 0) {
210 err = index;
211 goto no_slot;
212 }
213
214 ptp->clock.ops = ptp_clock_ops;
215 ptp->clock.release = delete_ptp_clock;
216 ptp->info = info;
217 ptp->devid = MKDEV(major, index);
218 ptp->index = index;
219 spin_lock_init(&ptp->tsevq.lock);
220 mutex_init(&ptp->tsevq_mux);
221 mutex_init(&ptp->pincfg_mux);
222 init_waitqueue_head(&ptp->tsev_wq);
223
224 /* Create a new device in our class. */
225 ptp->dev = device_create(ptp_class, parent, ptp->devid, ptp,
226 "ptp%d", ptp->index);
227 if (IS_ERR(ptp->dev))
228 goto no_device;
229
230 dev_set_drvdata(ptp->dev, ptp);
231
232 err = ptp_populate_sysfs(ptp);
233 if (err)
234 goto no_sysfs;
235
236 /* Register a new PPS source. */
237 if (info->pps) {
238 struct pps_source_info pps;
239 memset(&pps, 0, sizeof(pps));
240 snprintf(pps.name, PPS_MAX_NAME_LEN, "ptp%d", index);
241 pps.mode = PTP_PPS_MODE;
242 pps.owner = info->owner;
243 ptp->pps_source = pps_register_source(&pps, PTP_PPS_DEFAULTS);
244 if (!ptp->pps_source) {
245 pr_err("failed to register pps source\n");
246 goto no_pps;
247 }
248 }
249
250 /* Create a posix clock. */
251 err = posix_clock_register(&ptp->clock, ptp->devid);
252 if (err) {
253 pr_err("failed to create posix clock\n");
254 goto no_clock;
255 }
256
257 return ptp;
258
259no_clock:
260 if (ptp->pps_source)
261 pps_unregister_source(ptp->pps_source);
262no_pps:
263 ptp_cleanup_sysfs(ptp);
264no_sysfs:
265 device_destroy(ptp_class, ptp->devid);
266no_device:
267 mutex_destroy(&ptp->tsevq_mux);
268 mutex_destroy(&ptp->pincfg_mux);
269 ida_simple_remove(&ptp_clocks_map, index);
270no_slot:
271 kfree(ptp);
272no_memory:
273 return ERR_PTR(err);
274}
275EXPORT_SYMBOL(ptp_clock_register);
276
277int ptp_clock_unregister(struct ptp_clock *ptp)
278{
279 ptp->defunct = 1;
280 wake_up_interruptible(&ptp->tsev_wq);
281
282 /* Release the clock's resources. */
283 if (ptp->pps_source)
284 pps_unregister_source(ptp->pps_source);
285 ptp_cleanup_sysfs(ptp);
286 device_destroy(ptp_class, ptp->devid);
287
288 posix_clock_unregister(&ptp->clock);
289 return 0;
290}
291EXPORT_SYMBOL(ptp_clock_unregister);
292
293void ptp_clock_event(struct ptp_clock *ptp, struct ptp_clock_event *event)
294{
295 struct pps_event_time evt;
296
297 switch (event->type) {
298
299 case PTP_CLOCK_ALARM:
300 break;
301
302 case PTP_CLOCK_EXTTS:
303 enqueue_external_timestamp(&ptp->tsevq, event);
304 wake_up_interruptible(&ptp->tsev_wq);
305 break;
306
307 case PTP_CLOCK_PPS:
308 pps_get_ts(&evt);
309 pps_event(ptp->pps_source, &evt, PTP_PPS_EVENT, NULL);
310 break;
311
312 case PTP_CLOCK_PPSUSR:
313 pps_event(ptp->pps_source, &event->pps_times,
314 PTP_PPS_EVENT, NULL);
315 break;
316 }
317}
318EXPORT_SYMBOL(ptp_clock_event);
319
320int ptp_clock_index(struct ptp_clock *ptp)
321{
322 return ptp->index;
323}
324EXPORT_SYMBOL(ptp_clock_index);
325
326int ptp_find_pin(struct ptp_clock *ptp,
327 enum ptp_pin_function func, unsigned int chan)
328{
329 struct ptp_pin_desc *pin = NULL;
330 int i;
331
332 mutex_lock(&ptp->pincfg_mux);
333 for (i = 0; i < ptp->info->n_pins; i++) {
334 if (ptp->info->pin_config[i].func == func &&
335 ptp->info->pin_config[i].chan == chan) {
336 pin = &ptp->info->pin_config[i];
337 break;
338 }
339 }
340 mutex_unlock(&ptp->pincfg_mux);
341
342 return pin ? i : -1;
343}
344EXPORT_SYMBOL(ptp_find_pin);
345
346/* module operations */
347
348static void __exit ptp_exit(void)
349{
350 class_destroy(ptp_class);
351 unregister_chrdev_region(ptp_devt, MINORMASK + 1);
352 ida_destroy(&ptp_clocks_map);
353}
354
355static int __init ptp_init(void)
356{
357 int err;
358
359 ptp_class = class_create(THIS_MODULE, "ptp");
360 if (IS_ERR(ptp_class)) {
361 pr_err("ptp: failed to allocate class\n");
362 return PTR_ERR(ptp_class);
363 }
364
365 err = alloc_chrdev_region(&ptp_devt, 0, MINORMASK + 1, "ptp");
366 if (err < 0) {
367 pr_err("ptp: failed to allocate device region\n");
368 goto no_region;
369 }
370
371 ptp_class->dev_groups = ptp_groups;
372 pr_info("PTP clock support registered\n");
373 return 0;
374
375no_region:
376 class_destroy(ptp_class);
377 return err;
378}
379
380subsys_initcall(ptp_init);
381module_exit(ptp_exit);
382
383MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
384MODULE_DESCRIPTION("PTP clocks support");
385MODULE_LICENSE("GPL");