Merge branch 'fix/bcm2835-code' of git://git.kernel.org/pub/scm/linux/kernel/git...
[firefly-linux-kernel-4.4.55.git] / drivers / ptp / ptp_chardev.c
1 /*
2  * PTP 1588 clock support - character device implementation.
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/module.h>
21 #include <linux/posix-clock.h>
22 #include <linux/poll.h>
23 #include <linux/sched.h>
24 #include <linux/slab.h>
25
26 #include "ptp_private.h"
27
28 static int ptp_disable_pinfunc(struct ptp_clock_info *ops,
29                                enum ptp_pin_function func, unsigned int chan)
30 {
31         struct ptp_clock_request rq;
32         int err = 0;
33
34         memset(&rq, 0, sizeof(rq));
35
36         switch (func) {
37         case PTP_PF_NONE:
38                 break;
39         case PTP_PF_EXTTS:
40                 rq.type = PTP_CLK_REQ_EXTTS;
41                 rq.extts.index = chan;
42                 err = ops->enable(ops, &rq, 0);
43                 break;
44         case PTP_PF_PEROUT:
45                 rq.type = PTP_CLK_REQ_PEROUT;
46                 rq.perout.index = chan;
47                 err = ops->enable(ops, &rq, 0);
48                 break;
49         case PTP_PF_PHYSYNC:
50                 break;
51         default:
52                 return -EINVAL;
53         }
54
55         return err;
56 }
57
58 int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
59                     enum ptp_pin_function func, unsigned int chan)
60 {
61         struct ptp_clock_info *info = ptp->info;
62         struct ptp_pin_desc *pin1 = NULL, *pin2 = &info->pin_config[pin];
63         unsigned int i;
64
65         /* Check to see if any other pin previously had this function. */
66         for (i = 0; i < info->n_pins; i++) {
67                 if (info->pin_config[i].func == func &&
68                     info->pin_config[i].chan == chan) {
69                         pin1 = &info->pin_config[i];
70                         break;
71                 }
72         }
73         if (pin1 && i == pin)
74                 return 0;
75
76         /* Check the desired function and channel. */
77         switch (func) {
78         case PTP_PF_NONE:
79                 break;
80         case PTP_PF_EXTTS:
81                 if (chan >= info->n_ext_ts)
82                         return -EINVAL;
83                 break;
84         case PTP_PF_PEROUT:
85                 if (chan >= info->n_per_out)
86                         return -EINVAL;
87                 break;
88         case PTP_PF_PHYSYNC:
89                 if (chan != 0)
90                         return -EINVAL;
91         default:
92                 return -EINVAL;
93         }
94
95         if (info->verify(info, pin, func, chan)) {
96                 pr_err("driver cannot use function %u on pin %u\n", func, chan);
97                 return -EOPNOTSUPP;
98         }
99
100         /* Disable whatever function was previously assigned. */
101         if (pin1) {
102                 ptp_disable_pinfunc(info, func, chan);
103                 pin1->func = PTP_PF_NONE;
104                 pin1->chan = 0;
105         }
106         ptp_disable_pinfunc(info, pin2->func, pin2->chan);
107         pin2->func = func;
108         pin2->chan = chan;
109
110         return 0;
111 }
112
113 int ptp_open(struct posix_clock *pc, fmode_t fmode)
114 {
115         return 0;
116 }
117
118 long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
119 {
120         struct ptp_clock_caps caps;
121         struct ptp_clock_request req;
122         struct ptp_sys_offset *sysoff = NULL;
123         struct ptp_pin_desc pd;
124         struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
125         struct ptp_clock_info *ops = ptp->info;
126         struct ptp_clock_time *pct;
127         struct timespec64 ts;
128         int enable, err = 0;
129         unsigned int i, pin_index;
130
131         switch (cmd) {
132
133         case PTP_CLOCK_GETCAPS:
134                 memset(&caps, 0, sizeof(caps));
135                 caps.max_adj = ptp->info->max_adj;
136                 caps.n_alarm = ptp->info->n_alarm;
137                 caps.n_ext_ts = ptp->info->n_ext_ts;
138                 caps.n_per_out = ptp->info->n_per_out;
139                 caps.pps = ptp->info->pps;
140                 caps.n_pins = ptp->info->n_pins;
141                 if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
142                         err = -EFAULT;
143                 break;
144
145         case PTP_EXTTS_REQUEST:
146                 if (copy_from_user(&req.extts, (void __user *)arg,
147                                    sizeof(req.extts))) {
148                         err = -EFAULT;
149                         break;
150                 }
151                 if (req.extts.index >= ops->n_ext_ts) {
152                         err = -EINVAL;
153                         break;
154                 }
155                 req.type = PTP_CLK_REQ_EXTTS;
156                 enable = req.extts.flags & PTP_ENABLE_FEATURE ? 1 : 0;
157                 err = ops->enable(ops, &req, enable);
158                 break;
159
160         case PTP_PEROUT_REQUEST:
161                 if (copy_from_user(&req.perout, (void __user *)arg,
162                                    sizeof(req.perout))) {
163                         err = -EFAULT;
164                         break;
165                 }
166                 if (req.perout.index >= ops->n_per_out) {
167                         err = -EINVAL;
168                         break;
169                 }
170                 req.type = PTP_CLK_REQ_PEROUT;
171                 enable = req.perout.period.sec || req.perout.period.nsec;
172                 err = ops->enable(ops, &req, enable);
173                 break;
174
175         case PTP_ENABLE_PPS:
176                 if (!capable(CAP_SYS_TIME))
177                         return -EPERM;
178                 req.type = PTP_CLK_REQ_PPS;
179                 enable = arg ? 1 : 0;
180                 err = ops->enable(ops, &req, enable);
181                 break;
182
183         case PTP_SYS_OFFSET:
184                 sysoff = kmalloc(sizeof(*sysoff), GFP_KERNEL);
185                 if (!sysoff) {
186                         err = -ENOMEM;
187                         break;
188                 }
189                 if (copy_from_user(sysoff, (void __user *)arg,
190                                    sizeof(*sysoff))) {
191                         err = -EFAULT;
192                         break;
193                 }
194                 if (sysoff->n_samples > PTP_MAX_SAMPLES) {
195                         err = -EINVAL;
196                         break;
197                 }
198                 pct = &sysoff->ts[0];
199                 for (i = 0; i < sysoff->n_samples; i++) {
200                         getnstimeofday64(&ts);
201                         pct->sec = ts.tv_sec;
202                         pct->nsec = ts.tv_nsec;
203                         pct++;
204                         ptp->info->gettime64(ptp->info, &ts);
205                         pct->sec = ts.tv_sec;
206                         pct->nsec = ts.tv_nsec;
207                         pct++;
208                 }
209                 getnstimeofday64(&ts);
210                 pct->sec = ts.tv_sec;
211                 pct->nsec = ts.tv_nsec;
212                 if (copy_to_user((void __user *)arg, sysoff, sizeof(*sysoff)))
213                         err = -EFAULT;
214                 break;
215
216         case PTP_PIN_GETFUNC:
217                 if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
218                         err = -EFAULT;
219                         break;
220                 }
221                 pin_index = pd.index;
222                 if (pin_index >= ops->n_pins) {
223                         err = -EINVAL;
224                         break;
225                 }
226                 if (mutex_lock_interruptible(&ptp->pincfg_mux))
227                         return -ERESTARTSYS;
228                 pd = ops->pin_config[pin_index];
229                 mutex_unlock(&ptp->pincfg_mux);
230                 if (!err && copy_to_user((void __user *)arg, &pd, sizeof(pd)))
231                         err = -EFAULT;
232                 break;
233
234         case PTP_PIN_SETFUNC:
235                 if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
236                         err = -EFAULT;
237                         break;
238                 }
239                 pin_index = pd.index;
240                 if (pin_index >= ops->n_pins) {
241                         err = -EINVAL;
242                         break;
243                 }
244                 if (mutex_lock_interruptible(&ptp->pincfg_mux))
245                         return -ERESTARTSYS;
246                 err = ptp_set_pinfunc(ptp, pin_index, pd.func, pd.chan);
247                 mutex_unlock(&ptp->pincfg_mux);
248                 break;
249
250         default:
251                 err = -ENOTTY;
252                 break;
253         }
254
255         kfree(sysoff);
256         return err;
257 }
258
259 unsigned int ptp_poll(struct posix_clock *pc, struct file *fp, poll_table *wait)
260 {
261         struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
262
263         poll_wait(fp, &ptp->tsev_wq, wait);
264
265         return queue_cnt(&ptp->tsevq) ? POLLIN : 0;
266 }
267
268 #define EXTTS_BUFSIZE (PTP_BUF_TIMESTAMPS * sizeof(struct ptp_extts_event))
269
270 ssize_t ptp_read(struct posix_clock *pc,
271                  uint rdflags, char __user *buf, size_t cnt)
272 {
273         struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
274         struct timestamp_event_queue *queue = &ptp->tsevq;
275         struct ptp_extts_event *event;
276         unsigned long flags;
277         size_t qcnt, i;
278         int result;
279
280         if (cnt % sizeof(struct ptp_extts_event) != 0)
281                 return -EINVAL;
282
283         if (cnt > EXTTS_BUFSIZE)
284                 cnt = EXTTS_BUFSIZE;
285
286         cnt = cnt / sizeof(struct ptp_extts_event);
287
288         if (mutex_lock_interruptible(&ptp->tsevq_mux))
289                 return -ERESTARTSYS;
290
291         if (wait_event_interruptible(ptp->tsev_wq,
292                                      ptp->defunct || queue_cnt(queue))) {
293                 mutex_unlock(&ptp->tsevq_mux);
294                 return -ERESTARTSYS;
295         }
296
297         if (ptp->defunct) {
298                 mutex_unlock(&ptp->tsevq_mux);
299                 return -ENODEV;
300         }
301
302         event = kmalloc(EXTTS_BUFSIZE, GFP_KERNEL);
303         if (!event) {
304                 mutex_unlock(&ptp->tsevq_mux);
305                 return -ENOMEM;
306         }
307
308         spin_lock_irqsave(&queue->lock, flags);
309
310         qcnt = queue_cnt(queue);
311
312         if (cnt > qcnt)
313                 cnt = qcnt;
314
315         for (i = 0; i < cnt; i++) {
316                 event[i] = queue->buf[queue->head];
317                 queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
318         }
319
320         spin_unlock_irqrestore(&queue->lock, flags);
321
322         cnt = cnt * sizeof(struct ptp_extts_event);
323
324         mutex_unlock(&ptp->tsevq_mux);
325
326         result = cnt;
327         if (copy_to_user(buf, event, cnt))
328                 result = -EFAULT;
329
330         kfree(event);
331         return result;
332 }