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 int ptp_open(struct posix_clock *pc, fmode_t fmode) 29 { 30 return 0; 31 } 32 33 long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg) 34 { 35 struct ptp_clock_caps caps; 36 struct ptp_clock_request req; 37 struct ptp_sys_offset *sysoff = NULL; 38 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock); 39 struct ptp_clock_info *ops = ptp->info; 40 struct ptp_clock_time *pct; 41 struct timespec ts; 42 int enable, err = 0; 43 unsigned int i; 44 45 switch (cmd) { 46 47 case PTP_CLOCK_GETCAPS: 48 memset(&caps, 0, sizeof(caps)); 49 caps.max_adj = ptp->info->max_adj; 50 caps.n_alarm = ptp->info->n_alarm; 51 caps.n_ext_ts = ptp->info->n_ext_ts; 52 caps.n_per_out = ptp->info->n_per_out; 53 caps.pps = ptp->info->pps; 54 if (copy_to_user((void __user *)arg, &caps, sizeof(caps))) 55 err = -EFAULT; 56 break; 57 58 case PTP_EXTTS_REQUEST: 59 if (copy_from_user(&req.extts, (void __user *)arg, 60 sizeof(req.extts))) { 61 err = -EFAULT; 62 break; 63 } 64 if (req.extts.index >= ops->n_ext_ts) { 65 err = -EINVAL; 66 break; 67 } 68 req.type = PTP_CLK_REQ_EXTTS; 69 enable = req.extts.flags & PTP_ENABLE_FEATURE ? 1 : 0; 70 err = ops->enable(ops, &req, enable); 71 break; 72 73 case PTP_PEROUT_REQUEST: 74 if (copy_from_user(&req.perout, (void __user *)arg, 75 sizeof(req.perout))) { 76 err = -EFAULT; 77 break; 78 } 79 if (req.perout.index >= ops->n_per_out) { 80 err = -EINVAL; 81 break; 82 } 83 req.type = PTP_CLK_REQ_PEROUT; 84 enable = req.perout.period.sec || req.perout.period.nsec; 85 err = ops->enable(ops, &req, enable); 86 break; 87 88 case PTP_ENABLE_PPS: 89 if (!capable(CAP_SYS_TIME)) 90 return -EPERM; 91 req.type = PTP_CLK_REQ_PPS; 92 enable = arg ? 1 : 0; 93 err = ops->enable(ops, &req, enable); 94 break; 95 96 case PTP_SYS_OFFSET: 97 sysoff = kmalloc(sizeof(*sysoff), GFP_KERNEL); 98 if (!sysoff) { 99 err = -ENOMEM; 100 break; 101 } 102 if (copy_from_user(sysoff, (void __user *)arg, 103 sizeof(*sysoff))) { 104 err = -EFAULT; 105 break; 106 } 107 if (sysoff->n_samples > PTP_MAX_SAMPLES) { 108 err = -EINVAL; 109 break; 110 } 111 pct = &sysoff->ts[0]; 112 for (i = 0; i < sysoff->n_samples; i++) { 113 getnstimeofday(&ts); 114 pct->sec = ts.tv_sec; 115 pct->nsec = ts.tv_nsec; 116 pct++; 117 ptp->info->gettime(ptp->info, &ts); 118 pct->sec = ts.tv_sec; 119 pct->nsec = ts.tv_nsec; 120 pct++; 121 } 122 getnstimeofday(&ts); 123 pct->sec = ts.tv_sec; 124 pct->nsec = ts.tv_nsec; 125 if (copy_to_user((void __user *)arg, sysoff, sizeof(*sysoff))) 126 err = -EFAULT; 127 break; 128 129 default: 130 err = -ENOTTY; 131 break; 132 } 133 134 kfree(sysoff); 135 return err; 136 } 137 138 unsigned int ptp_poll(struct posix_clock *pc, struct file *fp, poll_table *wait) 139 { 140 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock); 141 142 poll_wait(fp, &ptp->tsev_wq, wait); 143 144 return queue_cnt(&ptp->tsevq) ? POLLIN : 0; 145 } 146 147 #define EXTTS_BUFSIZE (PTP_BUF_TIMESTAMPS * sizeof(struct ptp_extts_event)) 148 149 ssize_t ptp_read(struct posix_clock *pc, 150 uint rdflags, char __user *buf, size_t cnt) 151 { 152 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock); 153 struct timestamp_event_queue *queue = &ptp->tsevq; 154 struct ptp_extts_event *event; 155 unsigned long flags; 156 size_t qcnt, i; 157 int result; 158 159 if (cnt % sizeof(struct ptp_extts_event) != 0) 160 return -EINVAL; 161 162 if (cnt > EXTTS_BUFSIZE) 163 cnt = EXTTS_BUFSIZE; 164 165 cnt = cnt / sizeof(struct ptp_extts_event); 166 167 if (mutex_lock_interruptible(&ptp->tsevq_mux)) 168 return -ERESTARTSYS; 169 170 if (wait_event_interruptible(ptp->tsev_wq, 171 ptp->defunct || queue_cnt(queue))) { 172 mutex_unlock(&ptp->tsevq_mux); 173 return -ERESTARTSYS; 174 } 175 176 if (ptp->defunct) { 177 mutex_unlock(&ptp->tsevq_mux); 178 return -ENODEV; 179 } 180 181 event = kmalloc(EXTTS_BUFSIZE, GFP_KERNEL); 182 if (!event) { 183 mutex_unlock(&ptp->tsevq_mux); 184 return -ENOMEM; 185 } 186 187 spin_lock_irqsave(&queue->lock, flags); 188 189 qcnt = queue_cnt(queue); 190 191 if (cnt > qcnt) 192 cnt = qcnt; 193 194 for (i = 0; i < cnt; i++) { 195 event[i] = queue->buf[queue->head]; 196 queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS; 197 } 198 199 spin_unlock_irqrestore(&queue->lock, flags); 200 201 cnt = cnt * sizeof(struct ptp_extts_event); 202 203 mutex_unlock(&ptp->tsevq_mux); 204 205 result = cnt; 206 if (copy_to_user(buf, event, cnt)) 207 result = -EFAULT; 208 209 kfree(event); 210 return result; 211 } 212