/*
* PTP 1588 clock support - character device implementation.
*
* Copyright (C) 2010 OMICRON electronics GmbH
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/posix-clock.h>
#include <linux/poll.h>
#include <linux/sched.h>
#include "ptp_private.h"
int ptp_open(struct posix_clock *pc, fmode_t fmode)
{
return 0;
}
long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
{
struct ptp_clock_caps caps;
struct ptp_clock_request req;
struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
struct ptp_clock_info *ops = ptp->info;
int enable, err = 0;
switch (cmd) {
case PTP_CLOCK_GETCAPS:
memset(&caps, 0, sizeof(caps));
caps.max_adj = ptp->info->max_adj;
caps.n_alarm = ptp->info->n_alarm;
caps.n_ext_ts = ptp->info->n_ext_ts;
caps.n_per_out = ptp->info->n_per_out;
caps.pps = ptp->info->pps;
err = copy_to_user((void __user *)arg, &caps, sizeof(caps));
break;
case PTP_EXTTS_REQUEST:
if (copy_from_user(&req.extts, (void __user *)arg,
sizeof(req.extts))) {
err = -EFAULT;
break;
}
if (req.extts.index >= ops->n_ext_ts) {
err = -EINVAL;
break;
}
req.type = PTP_CLK_REQ_EXTTS;
enable = req.extts.flags & PTP_ENABLE_FEATURE ? 1 : 0;
err = ops->enable(ops, &req, enable);
break;
case PTP_PEROUT_REQUEST:
if (copy_from_user(&req.perout, (void __user *)arg,
sizeof(req.perout))) {
err = -EFAULT;
break;
}
if (req.perout.index >= ops->n_per_out) {
err = -EINVAL;
break;
}
req.type = PTP_CLK_REQ_PEROUT;
enable = req.perout.period.sec || req.perout.period.nsec;
err = ops->enable(ops, &req, enable);
break;
case PTP_ENABLE_PPS:
if (!capable(CAP_SYS_TIME))
return -EPERM;
req.type = PTP_CLK_REQ_PPS;
enable = arg ? 1 : 0;
err = ops->enable(ops, &req, enable);
break;
default:
err = -ENOTTY;
break;
}
return err;
}
unsigned int ptp_poll(struct posix_clock *pc, struct file *fp, poll_table *wait)
{
struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
poll_wait(fp, &ptp->tsev_wq, wait);
return queue_cnt(&ptp->tsevq) ? POLLIN : 0;
}
ssize_t ptp_read(struct posix_clock *pc,
uint rdflags, char __user *buf, size_t cnt)
{
struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
struct timestamp_event_queue *queue = &ptp->tsevq;
struct ptp_extts_event event[PTP_BUF_TIMESTAMPS];
unsigned long flags;
size_t qcnt, i;
if (cnt % sizeof(struct ptp_extts_event) != 0)
return -EINVAL;
if (cnt > sizeof(event))
cnt = sizeof(event);
cnt = cnt / sizeof(struct ptp_extts_event);
if (mutex_lock_interruptible(&ptp->tsevq_mux))
return -ERESTARTSYS;
if (wait_event_interruptible(ptp->tsev_wq,
ptp->defunct || queue_cnt(queue))) {
mutex_unlock(&ptp->tsevq_mux);
return -ERESTARTSYS;
}
if (ptp->defunct)
return -ENODEV;
spin_lock_irqsave(&queue->lock, flags);
qcnt = queue_cnt(queue);
if (cnt > qcnt)
cnt = qcnt;
for (i = 0; i < cnt; i++) {
event[i] = queue->buf[queue->head];
queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
}
spin_unlock_irqrestore(&queue->lock, flags);
cnt = cnt * sizeof(struct ptp_extts_event);
mutex_unlock(&ptp->tsevq_mux);
if (copy_to_user(buf, event, cnt)) {
mutex_unlock(&ptp->tsevq_mux);
return -EFAULT;
}
return cnt;
}
