[mirror_ubuntu-zesty-kernel.git] / drivers / ptp / ptp_chardev.c

/*
 * 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 <linux/slab.h>
#include <linux/timekeeping.h>

#include "ptp_private.h"

static int ptp_disable_pinfunc(struct ptp_clock_info *ops,
			       enum ptp_pin_function func, unsigned int chan)
{
	struct ptp_clock_request rq;
	int err = 0;

	memset(&rq, 0, sizeof(rq));

	switch (func) {
	case PTP_PF_NONE:
		break;
	case PTP_PF_EXTTS:
		rq.type = PTP_CLK_REQ_EXTTS;
		rq.extts.index = chan;
		err = ops->enable(ops, &rq, 0);
		break;
	case PTP_PF_PEROUT:
		rq.type = PTP_CLK_REQ_PEROUT;
		rq.perout.index = chan;
		err = ops->enable(ops, &rq, 0);
		break;
	case PTP_PF_PHYSYNC:
		break;
	default:
		return -EINVAL;
	}

	return err;
}

int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
		    enum ptp_pin_function func, unsigned int chan)
{
	struct ptp_clock_info *info = ptp->info;
	struct ptp_pin_desc *pin1 = NULL, *pin2 = &info->pin_config[pin];
	unsigned int i;

	/* Check to see if any other pin previously had this function. */
	for (i = 0; i < info->n_pins; i++) {
		if (info->pin_config[i].func == func &&
		    info->pin_config[i].chan == chan) {
			pin1 = &info->pin_config[i];
			break;
		}
	}
	if (pin1 && i == pin)
		return 0;

	/* Check the desired function and channel. */
	switch (func) {
	case PTP_PF_NONE:
		break;
	case PTP_PF_EXTTS:
		if (chan >= info->n_ext_ts)
			return -EINVAL;
		break;
	case PTP_PF_PEROUT:
		if (chan >= info->n_per_out)
			return -EINVAL;
		break;
	case PTP_PF_PHYSYNC:
		if (chan != 0)
			return -EINVAL;
	default:
		return -EINVAL;
	}

	if (info->verify(info, pin, func, chan)) {
		pr_err("driver cannot use function %u on pin %u\n", func, chan);
		return -EOPNOTSUPP;
	}

	/* Disable whatever function was previously assigned. */
	if (pin1) {
		ptp_disable_pinfunc(info, func, chan);
		pin1->func = PTP_PF_NONE;
		pin1->chan = 0;
	}
	ptp_disable_pinfunc(info, pin2->func, pin2->chan);
	pin2->func = func;
	pin2->chan = chan;

	return 0;
}

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_sys_offset *sysoff = NULL;
	struct ptp_sys_offset_precise precise_offset;
	struct ptp_pin_desc pd;
	struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
	struct ptp_clock_info *ops = ptp->info;
	struct ptp_clock_time *pct;
	struct timespec64 ts;
	struct system_device_crosststamp xtstamp;
	int enable, err = 0;
	unsigned int i, pin_index;

	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;
		caps.n_pins = ptp->info->n_pins;
		caps.cross_timestamping = ptp->info->getcrosststamp != NULL;
		if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
			err = -EFAULT;
		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;

	case PTP_SYS_OFFSET_PRECISE:
		if (!ptp->info->getcrosststamp) {
			err = -EOPNOTSUPP;
			break;
		}
		err = ptp->info->getcrosststamp(ptp->info, &xtstamp);
		if (err)
			break;

		memset(&precise_offset, 0, sizeof(precise_offset));
		ts = ktime_to_timespec64(xtstamp.device);
		precise_offset.device.sec = ts.tv_sec;
		precise_offset.device.nsec = ts.tv_nsec;
		ts = ktime_to_timespec64(xtstamp.sys_realtime);
		precise_offset.sys_realtime.sec = ts.tv_sec;
		precise_offset.sys_realtime.nsec = ts.tv_nsec;
		ts = ktime_to_timespec64(xtstamp.sys_monoraw);
		precise_offset.sys_monoraw.sec = ts.tv_sec;
		precise_offset.sys_monoraw.nsec = ts.tv_nsec;
		if (copy_to_user((void __user *)arg, &precise_offset,
				 sizeof(precise_offset)))
			err = -EFAULT;
		break;

	case PTP_SYS_OFFSET:
		sysoff = memdup_user((void __user *)arg, sizeof(*sysoff));
		if (IS_ERR(sysoff)) {
			err = PTR_ERR(sysoff);
			sysoff = NULL;
			break;
		}
		if (sysoff->n_samples > PTP_MAX_SAMPLES) {
			err = -EINVAL;
			break;
		}
		pct = &sysoff->ts[0];
		for (i = 0; i < sysoff->n_samples; i++) {
			getnstimeofday64(&ts);
			pct->sec = ts.tv_sec;
			pct->nsec = ts.tv_nsec;
			pct++;
			ptp->info->gettime64(ptp->info, &ts);
			pct->sec = ts.tv_sec;
			pct->nsec = ts.tv_nsec;
			pct++;
		}
		getnstimeofday64(&ts);
		pct->sec = ts.tv_sec;
		pct->nsec = ts.tv_nsec;
		if (copy_to_user((void __user *)arg, sysoff, sizeof(*sysoff)))
			err = -EFAULT;
		break;

	case PTP_PIN_GETFUNC:
		if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
			err = -EFAULT;
			break;
		}
		pin_index = pd.index;
		if (pin_index >= ops->n_pins) {
			err = -EINVAL;
			break;
		}
		if (mutex_lock_interruptible(&ptp->pincfg_mux))
			return -ERESTARTSYS;
		pd = ops->pin_config[pin_index];
		mutex_unlock(&ptp->pincfg_mux);
		if (!err && copy_to_user((void __user *)arg, &pd, sizeof(pd)))
			err = -EFAULT;
		break;

	case PTP_PIN_SETFUNC:
		if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
			err = -EFAULT;
			break;
		}
		pin_index = pd.index;
		if (pin_index >= ops->n_pins) {
			err = -EINVAL;
			break;
		}
		if (mutex_lock_interruptible(&ptp->pincfg_mux))
			return -ERESTARTSYS;
		err = ptp_set_pinfunc(ptp, pin_index, pd.func, pd.chan);
		mutex_unlock(&ptp->pincfg_mux);
		break;

	default:
		err = -ENOTTY;
		break;
	}

	kfree(sysoff);
	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;
}

#define EXTTS_BUFSIZE (PTP_BUF_TIMESTAMPS * sizeof(struct ptp_extts_event))

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;
	unsigned long flags;
	size_t qcnt, i;
	int result;

	if (cnt % sizeof(struct ptp_extts_event) != 0)
		return -EINVAL;

	if (cnt > EXTTS_BUFSIZE)
		cnt = EXTTS_BUFSIZE;

	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) {
		mutex_unlock(&ptp->tsevq_mux);
		return -ENODEV;
	}

	event = kmalloc(EXTTS_BUFSIZE, GFP_KERNEL);
	if (!event) {
		mutex_unlock(&ptp->tsevq_mux);
		return -ENOMEM;
	}

	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);

	result = cnt;
	if (copy_to_user(buf, event, cnt))
		result = -EFAULT;

	kfree(event);
	return result;
}
Commit	Line	Data
d94ba80e RC	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>
c7ec0bad	24	#include <linux/slab.h>
719f1aa4	25	#include <linux/timekeeping.h>
d94ba80e RC	26
	27	#include "ptp_private.h"
	28
6092315d RC	29	static int ptp_disable_pinfunc(struct ptp_clock_info *ops,
	30	enum ptp_pin_function func, unsigned int chan)
	31	{
	32	struct ptp_clock_request rq;
	33	int err = 0;
	34
	35	memset(&rq, 0, sizeof(rq));
	36
	37	switch (func) {
	38	case PTP_PF_NONE:
	39	break;
	40	case PTP_PF_EXTTS:
	41	rq.type = PTP_CLK_REQ_EXTTS;
	42	rq.extts.index = chan;
	43	err = ops->enable(ops, &rq, 0);
	44	break;
	45	case PTP_PF_PEROUT:
	46	rq.type = PTP_CLK_REQ_PEROUT;
	47	rq.perout.index = chan;
	48	err = ops->enable(ops, &rq, 0);
	49	break;
	50	case PTP_PF_PHYSYNC:
	51	break;
	52	default:
	53	return -EINVAL;
	54	}
	55
	56	return err;
	57	}
	58
	59	int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
	60	enum ptp_pin_function func, unsigned int chan)
	61	{
	62	struct ptp_clock_info *info = ptp->info;
	63	struct ptp_pin_desc pin1 = NULL, pin2 = &info->pin_config[pin];
	64	unsigned int i;
	65
	66	/* Check to see if any other pin previously had this function. */
	67	for (i = 0; i < info->n_pins; i++) {
	68	if (info->pin_config[i].func == func &&
	69	info->pin_config[i].chan == chan) {
	70	pin1 = &info->pin_config[i];
	71	break;
	72	}
	73	}
	74	if (pin1 && i == pin)
	75	return 0;
	76
	77	/* Check the desired function and channel. */
	78	switch (func) {
	79	case PTP_PF_NONE:
	80	break;
	81	case PTP_PF_EXTTS:
	82	if (chan >= info->n_ext_ts)
	83	return -EINVAL;
	84	break;
	85	case PTP_PF_PEROUT:
	86	if (chan >= info->n_per_out)
	87	return -EINVAL;
	88	break;
	89	case PTP_PF_PHYSYNC:
72df7a72 SS	90	if (chan != 0)
72df7a72 SS	91	return -EINVAL;
6092315d RC	92	default:
	93	return -EINVAL;
	94	}
	95
6092315d RC	96	if (info->verify(info, pin, func, chan)) {
	97	pr_err("driver cannot use function %u on pin %u\n", func, chan);
	98	return -EOPNOTSUPP;
	99	}
	100
	101	/* Disable whatever function was previously assigned. */
	102	if (pin1) {
	103	ptp_disable_pinfunc(info, func, chan);
	104	pin1->func = PTP_PF_NONE;
	105	pin1->chan = 0;
	106	}
	107	ptp_disable_pinfunc(info, pin2->func, pin2->chan);
	108	pin2->func = func;
	109	pin2->chan = chan;
	110
	111	return 0;
	112	}
	113
d94ba80e RC	114	int ptp_open(struct posix_clock *pc, fmode_t fmode)
	115	{
	116	return 0;
	117	}
	118
	119	long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
	120	{
	121	struct ptp_clock_caps caps;
	122	struct ptp_clock_request req;
c3484c27	123	struct ptp_sys_offset *sysoff = NULL;
719f1aa4	124	struct ptp_sys_offset_precise precise_offset;
6092315d	125	struct ptp_pin_desc pd;
d94ba80e RC	126	struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
d94ba80e RC	127	struct ptp_clock_info *ops = ptp->info;
215b13dd	128	struct ptp_clock_time *pct;
e13cfcb0	129	struct timespec64 ts;
719f1aa4	130	struct system_device_crosststamp xtstamp;
d94ba80e	131	int enable, err = 0;
6092315d	132	unsigned int i, pin_index;
d94ba80e RC	133
	134	switch (cmd) {
	135
	136	case PTP_CLOCK_GETCAPS:
	137	memset(&caps, 0, sizeof(caps));
	138	caps.max_adj = ptp->info->max_adj;
	139	caps.n_alarm = ptp->info->n_alarm;
	140	caps.n_ext_ts = ptp->info->n_ext_ts;
	141	caps.n_per_out = ptp->info->n_per_out;
	142	caps.pps = ptp->info->pps;
6092315d	143	caps.n_pins = ptp->info->n_pins;
719f1aa4	144	caps.cross_timestamping = ptp->info->getcrosststamp != NULL;
e23ef227 DC	145	if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
e23ef227 DC	146	err = -EFAULT;
d94ba80e RC	147	break;
	148
	149	case PTP_EXTTS_REQUEST:
	150	if (copy_from_user(&req.extts, (void __user *)arg,
	151	sizeof(req.extts))) {
	152	err = -EFAULT;
	153	break;
	154	}
	155	if (req.extts.index >= ops->n_ext_ts) {
	156	err = -EINVAL;
	157	break;
	158	}
	159	req.type = PTP_CLK_REQ_EXTTS;
	160	enable = req.extts.flags & PTP_ENABLE_FEATURE ? 1 : 0;
	161	err = ops->enable(ops, &req, enable);
	162	break;
	163
	164	case PTP_PEROUT_REQUEST:
	165	if (copy_from_user(&req.perout, (void __user *)arg,
	166	sizeof(req.perout))) {
	167	err = -EFAULT;
	168	break;
	169	}
	170	if (req.perout.index >= ops->n_per_out) {
	171	err = -EINVAL;
	172	break;
	173	}
	174	req.type = PTP_CLK_REQ_PEROUT;
	175	enable = req.perout.period.sec \|\| req.perout.period.nsec;
	176	err = ops->enable(ops, &req, enable);
	177	break;
	178
	179	case PTP_ENABLE_PPS:
	180	if (!capable(CAP_SYS_TIME))
	181	return -EPERM;
	182	req.type = PTP_CLK_REQ_PPS;
	183	enable = arg ? 1 : 0;
	184	err = ops->enable(ops, &req, enable);
	185	break;
	186
719f1aa4 CH	187	case PTP_SYS_OFFSET_PRECISE:
	188	if (!ptp->info->getcrosststamp) {
	189	err = -EOPNOTSUPP;
	190	break;
	191	}
	192	err = ptp->info->getcrosststamp(ptp->info, &xtstamp);
	193	if (err)
	194	break;
	195
02a9079c	196	memset(&precise_offset, 0, sizeof(precise_offset));
719f1aa4 CH	197	ts = ktime_to_timespec64(xtstamp.device);
	198	precise_offset.device.sec = ts.tv_sec;
	199	precise_offset.device.nsec = ts.tv_nsec;
	200	ts = ktime_to_timespec64(xtstamp.sys_realtime);
	201	precise_offset.sys_realtime.sec = ts.tv_sec;
	202	precise_offset.sys_realtime.nsec = ts.tv_nsec;
	203	ts = ktime_to_timespec64(xtstamp.sys_monoraw);
	204	precise_offset.sys_monoraw.sec = ts.tv_sec;
	205	precise_offset.sys_monoraw.nsec = ts.tv_nsec;
	206	if (copy_to_user((void __user *)arg, &precise_offset,
	207	sizeof(precise_offset)))
	208	err = -EFAULT;
	209	break;
	210
215b13dd	211	case PTP_SYS_OFFSET:
2ece068e MFW	212	sysoff = memdup_user((void __user )arg, sizeof(sysoff));
	213	if (IS_ERR(sysoff)) {
	214	err = PTR_ERR(sysoff);
6756325a	215	sysoff = NULL;
215b13dd RC	216	break;
215b13dd RC	217	}
c3484c27	218	if (sysoff->n_samples > PTP_MAX_SAMPLES) {
215b13dd RC	219	err = -EINVAL;
	220	break;
	221	}
c3484c27 RC	222	pct = &sysoff->ts[0];
c3484c27 RC	223	for (i = 0; i < sysoff->n_samples; i++) {
e13cfcb0	224	getnstimeofday64(&ts);
215b13dd RC	225	pct->sec = ts.tv_sec;
	226	pct->nsec = ts.tv_nsec;
	227	pct++;
ed7c6317	228	ptp->info->gettime64(ptp->info, &ts);
215b13dd RC	229	pct->sec = ts.tv_sec;
	230	pct->nsec = ts.tv_nsec;
	231	pct++;
	232	}
e13cfcb0	233	getnstimeofday64(&ts);
215b13dd RC	234	pct->sec = ts.tv_sec;
215b13dd RC	235	pct->nsec = ts.tv_nsec;
c3484c27	236	if (copy_to_user((void __user )arg, sysoff, sizeof(sysoff)))
215b13dd RC	237	err = -EFAULT;
	238	break;
	239
6092315d RC	240	case PTP_PIN_GETFUNC:
	241	if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
	242	err = -EFAULT;
	243	break;
	244	}
	245	pin_index = pd.index;
	246	if (pin_index >= ops->n_pins) {
	247	err = -EINVAL;
	248	break;
	249	}
	250	if (mutex_lock_interruptible(&ptp->pincfg_mux))
	251	return -ERESTARTSYS;
	252	pd = ops->pin_config[pin_index];
	253	mutex_unlock(&ptp->pincfg_mux);
	254	if (!err && copy_to_user((void __user *)arg, &pd, sizeof(pd)))
	255	err = -EFAULT;
	256	break;
	257
	258	case PTP_PIN_SETFUNC:
	259	if (copy_from_user(&pd, (void __user *)arg, sizeof(pd))) {
	260	err = -EFAULT;
	261	break;
	262	}
	263	pin_index = pd.index;
	264	if (pin_index >= ops->n_pins) {
	265	err = -EINVAL;
	266	break;
	267	}
	268	if (mutex_lock_interruptible(&ptp->pincfg_mux))
	269	return -ERESTARTSYS;
	270	err = ptp_set_pinfunc(ptp, pin_index, pd.func, pd.chan);
	271	mutex_unlock(&ptp->pincfg_mux);
	272	break;
	273
d94ba80e RC	274	default:
	275	err = -ENOTTY;
	276	break;
	277	}
c3484c27 RC	278
c3484c27 RC	279	kfree(sysoff);
d94ba80e RC	280	return err;
	281	}
	282
	283	unsigned int ptp_poll(struct posix_clock pc, struct file fp, poll_table *wait)
	284	{
	285	struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
	286
	287	poll_wait(fp, &ptp->tsev_wq, wait);
	288
	289	return queue_cnt(&ptp->tsevq) ? POLLIN : 0;
	290	}
	291
c7ec0bad RC	292	#define EXTTS_BUFSIZE (PTP_BUF_TIMESTAMPS * sizeof(struct ptp_extts_event))
c7ec0bad RC	293
d94ba80e RC	294	ssize_t ptp_read(struct posix_clock *pc,
	295	uint rdflags, char __user *buf, size_t cnt)
	296	{
	297	struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
	298	struct timestamp_event_queue *queue = &ptp->tsevq;
c7ec0bad	299	struct ptp_extts_event *event;
d94ba80e RC	300	unsigned long flags;
d94ba80e RC	301	size_t qcnt, i;
c7ec0bad	302	int result;
d94ba80e RC	303
	304	if (cnt % sizeof(struct ptp_extts_event) != 0)
	305	return -EINVAL;
	306
c7ec0bad RC	307	if (cnt > EXTTS_BUFSIZE)
c7ec0bad RC	308	cnt = EXTTS_BUFSIZE;
d94ba80e RC	309
	310	cnt = cnt / sizeof(struct ptp_extts_event);
	311
	312	if (mutex_lock_interruptible(&ptp->tsevq_mux))
	313	return -ERESTARTSYS;
	314
	315	if (wait_event_interruptible(ptp->tsev_wq,
	316	ptp->defunct \|\| queue_cnt(queue))) {
	317	mutex_unlock(&ptp->tsevq_mux);
	318	return -ERESTARTSYS;
	319	}
	320
fb5a18cf DC	321	if (ptp->defunct) {
fb5a18cf DC	322	mutex_unlock(&ptp->tsevq_mux);
d94ba80e	323	return -ENODEV;
fb5a18cf	324	}
d94ba80e	325
c7ec0bad RC	326	event = kmalloc(EXTTS_BUFSIZE, GFP_KERNEL);
	327	if (!event) {
	328	mutex_unlock(&ptp->tsevq_mux);
	329	return -ENOMEM;
	330	}
	331
d94ba80e RC	332	spin_lock_irqsave(&queue->lock, flags);
	333
	334	qcnt = queue_cnt(queue);
	335
	336	if (cnt > qcnt)
	337	cnt = qcnt;
	338
	339	for (i = 0; i < cnt; i++) {
	340	event[i] = queue->buf[queue->head];
	341	queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
	342	}
	343
	344	spin_unlock_irqrestore(&queue->lock, flags);
	345
	346	cnt = cnt * sizeof(struct ptp_extts_event);
	347
	348	mutex_unlock(&ptp->tsevq_mux);
	349
c7ec0bad	350	result = cnt;
fb5a18cf	351	if (copy_to_user(buf, event, cnt))
c7ec0bad	352	result = -EFAULT;
d94ba80e	353
c7ec0bad RC	354	kfree(event);
c7ec0bad RC	355	return result;
d94ba80e	356	}