[mirror_ubuntu-jammy-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 "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_sys_offset sysoff;
	struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
	struct ptp_clock_info *ops = ptp->info;
	struct ptp_clock_time *pct;
	struct timespec ts;
	int enable, err = 0;
	unsigned int i;

	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;
		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:
		if (copy_from_user(&sysoff, (void __user *)arg,
				   sizeof(sysoff))) {
			err = -EFAULT;
			break;
		}
		if (sysoff.n_samples > PTP_MAX_SAMPLES) {
			err = -EINVAL;
			break;
		}
		pct = &sysoff.ts[0];
		for (i = 0; i < sysoff.n_samples; i++) {
			getnstimeofday(&ts);
			pct->sec = ts.tv_sec;
			pct->nsec = ts.tv_nsec;
			pct++;
			ptp->info->gettime(ptp->info, &ts);
			pct->sec = ts.tv_sec;
			pct->nsec = ts.tv_nsec;
			pct++;
		}
		getnstimeofday(&ts);
		pct->sec = ts.tv_sec;
		pct->nsec = ts.tv_nsec;
		if (copy_to_user((void __user *)arg, &sysoff, sizeof(sysoff)))
			err = -EFAULT;
		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;
}

#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>
d94ba80e RC	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;
215b13dd	37	struct ptp_sys_offset sysoff;
d94ba80e RC	38	struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
d94ba80e RC	39	struct ptp_clock_info *ops = ptp->info;
215b13dd RC	40	struct ptp_clock_time *pct;
215b13dd RC	41	struct timespec ts;
d94ba80e	42	int enable, err = 0;
215b13dd	43	unsigned int i;
d94ba80e RC	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;
e23ef227 DC	54	if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
e23ef227 DC	55	err = -EFAULT;
d94ba80e RC	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
215b13dd RC	96	case PTP_SYS_OFFSET:
	97	if (copy_from_user(&sysoff, (void __user *)arg,
	98	sizeof(sysoff))) {
	99	err = -EFAULT;
	100	break;
	101	}
	102	if (sysoff.n_samples > PTP_MAX_SAMPLES) {
	103	err = -EINVAL;
	104	break;
	105	}
	106	pct = &sysoff.ts[0];
	107	for (i = 0; i < sysoff.n_samples; i++) {
	108	getnstimeofday(&ts);
	109	pct->sec = ts.tv_sec;
	110	pct->nsec = ts.tv_nsec;
	111	pct++;
	112	ptp->info->gettime(ptp->info, &ts);
	113	pct->sec = ts.tv_sec;
	114	pct->nsec = ts.tv_nsec;
	115	pct++;
	116	}
	117	getnstimeofday(&ts);
	118	pct->sec = ts.tv_sec;
	119	pct->nsec = ts.tv_nsec;
	120	if (copy_to_user((void __user *)arg, &sysoff, sizeof(sysoff)))
	121	err = -EFAULT;
	122	break;
	123
d94ba80e RC	124	default:
	125	err = -ENOTTY;
	126	break;
	127	}
	128	return err;
	129	}
	130
	131	unsigned int ptp_poll(struct posix_clock pc, struct file fp, poll_table *wait)
	132	{
	133	struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
	134
	135	poll_wait(fp, &ptp->tsev_wq, wait);
	136
	137	return queue_cnt(&ptp->tsevq) ? POLLIN : 0;
	138	}
	139
c7ec0bad RC	140	#define EXTTS_BUFSIZE (PTP_BUF_TIMESTAMPS * sizeof(struct ptp_extts_event))
c7ec0bad RC	141
d94ba80e RC	142	ssize_t ptp_read(struct posix_clock *pc,
	143	uint rdflags, char __user *buf, size_t cnt)
	144	{
	145	struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
	146	struct timestamp_event_queue *queue = &ptp->tsevq;
c7ec0bad	147	struct ptp_extts_event *event;
d94ba80e RC	148	unsigned long flags;
d94ba80e RC	149	size_t qcnt, i;
c7ec0bad	150	int result;
d94ba80e RC	151
	152	if (cnt % sizeof(struct ptp_extts_event) != 0)
	153	return -EINVAL;
	154
c7ec0bad RC	155	if (cnt > EXTTS_BUFSIZE)
c7ec0bad RC	156	cnt = EXTTS_BUFSIZE;
d94ba80e RC	157
	158	cnt = cnt / sizeof(struct ptp_extts_event);
	159
	160	if (mutex_lock_interruptible(&ptp->tsevq_mux))
	161	return -ERESTARTSYS;
	162
	163	if (wait_event_interruptible(ptp->tsev_wq,
	164	ptp->defunct \|\| queue_cnt(queue))) {
	165	mutex_unlock(&ptp->tsevq_mux);
	166	return -ERESTARTSYS;
	167	}
	168
fb5a18cf DC	169	if (ptp->defunct) {
fb5a18cf DC	170	mutex_unlock(&ptp->tsevq_mux);
d94ba80e	171	return -ENODEV;
fb5a18cf	172	}
d94ba80e	173
c7ec0bad RC	174	event = kmalloc(EXTTS_BUFSIZE, GFP_KERNEL);
	175	if (!event) {
	176	mutex_unlock(&ptp->tsevq_mux);
	177	return -ENOMEM;
	178	}
	179
d94ba80e RC	180	spin_lock_irqsave(&queue->lock, flags);
	181
	182	qcnt = queue_cnt(queue);
	183
	184	if (cnt > qcnt)
	185	cnt = qcnt;
	186
	187	for (i = 0; i < cnt; i++) {
	188	event[i] = queue->buf[queue->head];
	189	queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
	190	}
	191
	192	spin_unlock_irqrestore(&queue->lock, flags);
	193
	194	cnt = cnt * sizeof(struct ptp_extts_event);
	195
	196	mutex_unlock(&ptp->tsevq_mux);
	197
c7ec0bad	198	result = cnt;
fb5a18cf	199	if (copy_to_user(buf, event, cnt))
c7ec0bad	200	result = -EFAULT;
d94ba80e	201
c7ec0bad RC	202	kfree(event);
c7ec0bad RC	203	return result;
d94ba80e	204	}