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 #include <linux/timekeeping.h> 26 27 #include <linux/nospec.h> 28 29 #include "ptp_private.h" 30 31 static int ptp_disable_pinfunc(struct ptp_clock_info *ops, 32 enum ptp_pin_function func, unsigned int chan) 33 { 34 struct ptp_clock_request rq; 35 int err = 0; 36 37 memset(&rq, 0, sizeof(rq)); 38 39 switch (func) { 40 case PTP_PF_NONE: 41 break; 42 case PTP_PF_EXTTS: 43 rq.type = PTP_CLK_REQ_EXTTS; 44 rq.extts.index = chan; 45 err = ops->enable(ops, &rq, 0); 46 break; 47 case PTP_PF_PEROUT: 48 rq.type = PTP_CLK_REQ_PEROUT; 49 rq.perout.index = chan; 50 err = ops->enable(ops, &rq, 0); 51 break; 52 case PTP_PF_PHYSYNC: 53 break; 54 default: 55 return -EINVAL; 56 } 57 58 return err; 59 } 60 61 int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin, 62 enum ptp_pin_function func, unsigned int chan) 63 { 64 struct ptp_clock_info *info = ptp->info; 65 struct ptp_pin_desc *pin1 = NULL, *pin2 = &info->pin_config[pin]; 66 unsigned int i; 67 68 /* Check to see if any other pin previously had this function. */ 69 for (i = 0; i < info->n_pins; i++) { 70 if (info->pin_config[i].func == func && 71 info->pin_config[i].chan == chan) { 72 pin1 = &info->pin_config[i]; 73 break; 74 } 75 } 76 if (pin1 && i == pin) 77 return 0; 78 79 /* Check the desired function and channel. */ 80 switch (func) { 81 case PTP_PF_NONE: 82 break; 83 case PTP_PF_EXTTS: 84 if (chan >= info->n_ext_ts) 85 return -EINVAL; 86 break; 87 case PTP_PF_PEROUT: 88 if (chan >= info->n_per_out) 89 return -EINVAL; 90 break; 91 case PTP_PF_PHYSYNC: 92 if (chan != 0) 93 return -EINVAL; 94 break; 95 default: 96 return -EINVAL; 97 } 98 99 if (info->verify(info, pin, func, chan)) { 100 pr_err("driver cannot use function %u on pin %u\n", func, chan); 101 return -EOPNOTSUPP; 102 } 103 104 /* Disable whatever function was previously assigned. */ 105 if (pin1) { 106 ptp_disable_pinfunc(info, func, chan); 107 pin1->func = PTP_PF_NONE; 108 pin1->chan = 0; 109 } 110 ptp_disable_pinfunc(info, pin2->func, pin2->chan); 111 pin2->func = func; 112 pin2->chan = chan; 113 114 return 0; 115 } 116 117 int ptp_open(struct posix_clock *pc, fmode_t fmode) 118 { 119 return 0; 120 } 121 122 long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg) 123 { 124 struct ptp_clock_caps caps; 125 struct ptp_clock_request req; 126 struct ptp_sys_offset *sysoff = NULL; 127 struct ptp_sys_offset_precise precise_offset; 128 struct ptp_pin_desc pd; 129 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock); 130 struct ptp_clock_info *ops = ptp->info; 131 struct ptp_clock_time *pct; 132 struct timespec64 ts; 133 struct system_device_crosststamp xtstamp; 134 int enable, err = 0; 135 unsigned int i, pin_index; 136 137 switch (cmd) { 138 139 case PTP_CLOCK_GETCAPS: 140 memset(&caps, 0, sizeof(caps)); 141 caps.max_adj = ptp->info->max_adj; 142 caps.n_alarm = ptp->info->n_alarm; 143 caps.n_ext_ts = ptp->info->n_ext_ts; 144 caps.n_per_out = ptp->info->n_per_out; 145 caps.pps = ptp->info->pps; 146 caps.n_pins = ptp->info->n_pins; 147 caps.cross_timestamping = ptp->info->getcrosststamp != NULL; 148 if (copy_to_user((void __user *)arg, &caps, sizeof(caps))) 149 err = -EFAULT; 150 break; 151 152 case PTP_EXTTS_REQUEST: 153 if (copy_from_user(&req.extts, (void __user *)arg, 154 sizeof(req.extts))) { 155 err = -EFAULT; 156 break; 157 } 158 if (req.extts.index >= ops->n_ext_ts) { 159 err = -EINVAL; 160 break; 161 } 162 req.type = PTP_CLK_REQ_EXTTS; 163 enable = req.extts.flags & PTP_ENABLE_FEATURE ? 1 : 0; 164 err = ops->enable(ops, &req, enable); 165 break; 166 167 case PTP_PEROUT_REQUEST: 168 if (copy_from_user(&req.perout, (void __user *)arg, 169 sizeof(req.perout))) { 170 err = -EFAULT; 171 break; 172 } 173 if (req.perout.index >= ops->n_per_out) { 174 err = -EINVAL; 175 break; 176 } 177 req.type = PTP_CLK_REQ_PEROUT; 178 enable = req.perout.period.sec || req.perout.period.nsec; 179 err = ops->enable(ops, &req, enable); 180 break; 181 182 case PTP_ENABLE_PPS: 183 if (!capable(CAP_SYS_TIME)) 184 return -EPERM; 185 req.type = PTP_CLK_REQ_PPS; 186 enable = arg ? 1 : 0; 187 err = ops->enable(ops, &req, enable); 188 break; 189 190 case PTP_SYS_OFFSET_PRECISE: 191 if (!ptp->info->getcrosststamp) { 192 err = -EOPNOTSUPP; 193 break; 194 } 195 err = ptp->info->getcrosststamp(ptp->info, &xtstamp); 196 if (err) 197 break; 198 199 memset(&precise_offset, 0, sizeof(precise_offset)); 200 ts = ktime_to_timespec64(xtstamp.device); 201 precise_offset.device.sec = ts.tv_sec; 202 precise_offset.device.nsec = ts.tv_nsec; 203 ts = ktime_to_timespec64(xtstamp.sys_realtime); 204 precise_offset.sys_realtime.sec = ts.tv_sec; 205 precise_offset.sys_realtime.nsec = ts.tv_nsec; 206 ts = ktime_to_timespec64(xtstamp.sys_monoraw); 207 precise_offset.sys_monoraw.sec = ts.tv_sec; 208 precise_offset.sys_monoraw.nsec = ts.tv_nsec; 209 if (copy_to_user((void __user *)arg, &precise_offset, 210 sizeof(precise_offset))) 211 err = -EFAULT; 212 break; 213 214 case PTP_SYS_OFFSET: 215 sysoff = memdup_user((void __user *)arg, sizeof(*sysoff)); 216 if (IS_ERR(sysoff)) { 217 err = PTR_ERR(sysoff); 218 sysoff = NULL; 219 break; 220 } 221 if (sysoff->n_samples > PTP_MAX_SAMPLES) { 222 err = -EINVAL; 223 break; 224 } 225 pct = &sysoff->ts[0]; 226 for (i = 0; i < sysoff->n_samples; i++) { 227 ktime_get_real_ts64(&ts); 228 pct->sec = ts.tv_sec; 229 pct->nsec = ts.tv_nsec; 230 pct++; 231 ptp->info->gettime64(ptp->info, &ts); 232 pct->sec = ts.tv_sec; 233 pct->nsec = ts.tv_nsec; 234 pct++; 235 } 236 ktime_get_real_ts64(&ts); 237 pct->sec = ts.tv_sec; 238 pct->nsec = ts.tv_nsec; 239 if (copy_to_user((void __user *)arg, sysoff, sizeof(*sysoff))) 240 err = -EFAULT; 241 break; 242 243 case PTP_PIN_GETFUNC: 244 if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) { 245 err = -EFAULT; 246 break; 247 } 248 pin_index = pd.index; 249 if (pin_index >= ops->n_pins) { 250 err = -EINVAL; 251 break; 252 } 253 pin_index = array_index_nospec(pin_index, ops->n_pins); 254 if (mutex_lock_interruptible(&ptp->pincfg_mux)) 255 return -ERESTARTSYS; 256 pd = ops->pin_config[pin_index]; 257 mutex_unlock(&ptp->pincfg_mux); 258 if (!err && copy_to_user((void __user *)arg, &pd, sizeof(pd))) 259 err = -EFAULT; 260 break; 261 262 case PTP_PIN_SETFUNC: 263 if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) { 264 err = -EFAULT; 265 break; 266 } 267 pin_index = pd.index; 268 if (pin_index >= ops->n_pins) { 269 err = -EINVAL; 270 break; 271 } 272 pin_index = array_index_nospec(pin_index, ops->n_pins); 273 if (mutex_lock_interruptible(&ptp->pincfg_mux)) 274 return -ERESTARTSYS; 275 err = ptp_set_pinfunc(ptp, pin_index, pd.func, pd.chan); 276 mutex_unlock(&ptp->pincfg_mux); 277 break; 278 279 default: 280 err = -ENOTTY; 281 break; 282 } 283 284 kfree(sysoff); 285 return err; 286 } 287 288 __poll_t ptp_poll(struct posix_clock *pc, struct file *fp, poll_table *wait) 289 { 290 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock); 291 292 poll_wait(fp, &ptp->tsev_wq, wait); 293 294 return queue_cnt(&ptp->tsevq) ? EPOLLIN : 0; 295 } 296 297 #define EXTTS_BUFSIZE (PTP_BUF_TIMESTAMPS * sizeof(struct ptp_extts_event)) 298 299 ssize_t ptp_read(struct posix_clock *pc, 300 uint rdflags, char __user *buf, size_t cnt) 301 { 302 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock); 303 struct timestamp_event_queue *queue = &ptp->tsevq; 304 struct ptp_extts_event *event; 305 unsigned long flags; 306 size_t qcnt, i; 307 int result; 308 309 if (cnt % sizeof(struct ptp_extts_event) != 0) 310 return -EINVAL; 311 312 if (cnt > EXTTS_BUFSIZE) 313 cnt = EXTTS_BUFSIZE; 314 315 cnt = cnt / sizeof(struct ptp_extts_event); 316 317 if (mutex_lock_interruptible(&ptp->tsevq_mux)) 318 return -ERESTARTSYS; 319 320 if (wait_event_interruptible(ptp->tsev_wq, 321 ptp->defunct || queue_cnt(queue))) { 322 mutex_unlock(&ptp->tsevq_mux); 323 return -ERESTARTSYS; 324 } 325 326 if (ptp->defunct) { 327 mutex_unlock(&ptp->tsevq_mux); 328 return -ENODEV; 329 } 330 331 event = kmalloc(EXTTS_BUFSIZE, GFP_KERNEL); 332 if (!event) { 333 mutex_unlock(&ptp->tsevq_mux); 334 return -ENOMEM; 335 } 336 337 spin_lock_irqsave(&queue->lock, flags); 338 339 qcnt = queue_cnt(queue); 340 341 if (cnt > qcnt) 342 cnt = qcnt; 343 344 for (i = 0; i < cnt; i++) { 345 event[i] = queue->buf[queue->head]; 346 queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS; 347 } 348 349 spin_unlock_irqrestore(&queue->lock, flags); 350 351 cnt = cnt * sizeof(struct ptp_extts_event); 352 353 mutex_unlock(&ptp->tsevq_mux); 354 355 result = cnt; 356 if (copy_to_user(buf, event, cnt)) 357 result = -EFAULT; 358 359 kfree(event); 360 return result; 361 } 362