1/*
  2 * PTP 1588 clock support - sysfs interface.
  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/capability.h>
 21
 22#include "ptp_private.h"
 23
 24static ssize_t clock_name_show(struct device *dev,
 25			       struct device_attribute *attr, char *page)
 26{
 27	struct ptp_clock *ptp = dev_get_drvdata(dev);
 28	return snprintf(page, PAGE_SIZE-1, "%s\n", ptp->info->name);
 29}
 30
 31#define PTP_SHOW_INT(name)						\
 32static ssize_t name##_show(struct device *dev,				\
 33			   struct device_attribute *attr, char *page)	\
 34{									\
 35	struct ptp_clock *ptp = dev_get_drvdata(dev);			\
 36	return snprintf(page, PAGE_SIZE-1, "%d\n", ptp->info->name);	\
 37}
 38
 39PTP_SHOW_INT(max_adj);
 40PTP_SHOW_INT(n_alarm);
 41PTP_SHOW_INT(n_ext_ts);
 42PTP_SHOW_INT(n_per_out);
 43PTP_SHOW_INT(pps);
 44
 45#define PTP_RO_ATTR(_var, _name) {				\
 46	.attr	= { .name = __stringify(_name), .mode = 0444 },	\
 47	.show	= _var##_show,					\
 48}
 49
 50struct device_attribute ptp_dev_attrs[] = {
 51	PTP_RO_ATTR(clock_name,	clock_name),
 52	PTP_RO_ATTR(max_adj,	max_adjustment),
 53	PTP_RO_ATTR(n_alarm,	n_alarms),
 54	PTP_RO_ATTR(n_ext_ts,	n_external_timestamps),
 55	PTP_RO_ATTR(n_per_out,	n_periodic_outputs),
 56	PTP_RO_ATTR(pps,	pps_available),
 57	__ATTR_NULL,
 58};
 59
 60static ssize_t extts_enable_store(struct device *dev,
 61				  struct device_attribute *attr,
 62				  const char *buf, size_t count)
 63{
 64	struct ptp_clock *ptp = dev_get_drvdata(dev);
 65	struct ptp_clock_info *ops = ptp->info;
 66	struct ptp_clock_request req = { .type = PTP_CLK_REQ_EXTTS };
 67	int cnt, enable;
 68	int err = -EINVAL;
 69
 70	cnt = sscanf(buf, "%u %d", &req.extts.index, &enable);
 71	if (cnt != 2)
 72		goto out;
 73	if (req.extts.index >= ops->n_ext_ts)
 74		goto out;
 75
 76	err = ops->enable(ops, &req, enable ? 1 : 0);
 77	if (err)
 78		goto out;
 79
 80	return count;
 81out:
 82	return err;
 83}
 84
 85static ssize_t extts_fifo_show(struct device *dev,
 86			       struct device_attribute *attr, char *page)
 87{
 88	struct ptp_clock *ptp = dev_get_drvdata(dev);
 89	struct timestamp_event_queue *queue = &ptp->tsevq;
 90	struct ptp_extts_event event;
 91	unsigned long flags;
 92	size_t qcnt;
 93	int cnt = 0;
 94
 95	memset(&event, 0, sizeof(event));
 96
 97	if (mutex_lock_interruptible(&ptp->tsevq_mux))
 98		return -ERESTARTSYS;
 99
100	spin_lock_irqsave(&queue->lock, flags);
101	qcnt = queue_cnt(queue);
102	if (qcnt) {
103		event = queue->buf[queue->head];
104		queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
105	}
106	spin_unlock_irqrestore(&queue->lock, flags);
107
108	if (!qcnt)
109		goto out;
110
111	cnt = snprintf(page, PAGE_SIZE, "%u %lld %u\n",
112		       event.index, event.t.sec, event.t.nsec);
113out:
114	mutex_unlock(&ptp->tsevq_mux);
115	return cnt;
116}
117
118static ssize_t period_store(struct device *dev,
119			    struct device_attribute *attr,
120			    const char *buf, size_t count)
121{
122	struct ptp_clock *ptp = dev_get_drvdata(dev);
123	struct ptp_clock_info *ops = ptp->info;
124	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PEROUT };
125	int cnt, enable, err = -EINVAL;
126
127	cnt = sscanf(buf, "%u %lld %u %lld %u", &req.perout.index,
128		     &req.perout.start.sec, &req.perout.start.nsec,
129		     &req.perout.period.sec, &req.perout.period.nsec);
130	if (cnt != 5)
131		goto out;
132	if (req.perout.index >= ops->n_per_out)
133		goto out;
134
135	enable = req.perout.period.sec || req.perout.period.nsec;
136	err = ops->enable(ops, &req, enable);
137	if (err)
138		goto out;
139
140	return count;
141out:
142	return err;
143}
144
145static ssize_t pps_enable_store(struct device *dev,
146				struct device_attribute *attr,
147				const char *buf, size_t count)
148{
149	struct ptp_clock *ptp = dev_get_drvdata(dev);
150	struct ptp_clock_info *ops = ptp->info;
151	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PPS };
152	int cnt, enable;
153	int err = -EINVAL;
154
155	if (!capable(CAP_SYS_TIME))
156		return -EPERM;
157
158	cnt = sscanf(buf, "%d", &enable);
159	if (cnt != 1)
160		goto out;
161
162	err = ops->enable(ops, &req, enable ? 1 : 0);
163	if (err)
164		goto out;
165
166	return count;
167out:
168	return err;
169}
170
171static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store);
172static DEVICE_ATTR(fifo,         0444, extts_fifo_show, NULL);
173static DEVICE_ATTR(period,       0220, NULL, period_store);
174static DEVICE_ATTR(pps_enable,   0220, NULL, pps_enable_store);
175
176int ptp_cleanup_sysfs(struct ptp_clock *ptp)
177{
178	struct device *dev = ptp->dev;
179	struct ptp_clock_info *info = ptp->info;
180
181	if (info->n_ext_ts) {
182		device_remove_file(dev, &dev_attr_extts_enable);
183		device_remove_file(dev, &dev_attr_fifo);
184	}
185	if (info->n_per_out)
186		device_remove_file(dev, &dev_attr_period);
187
188	if (info->pps)
189		device_remove_file(dev, &dev_attr_pps_enable);
190
191	return 0;
192}
193
194int ptp_populate_sysfs(struct ptp_clock *ptp)
195{
196	struct device *dev = ptp->dev;
197	struct ptp_clock_info *info = ptp->info;
198	int err;
199
200	if (info->n_ext_ts) {
201		err = device_create_file(dev, &dev_attr_extts_enable);
202		if (err)
203			goto out1;
204		err = device_create_file(dev, &dev_attr_fifo);
205		if (err)
206			goto out2;
207	}
208	if (info->n_per_out) {
209		err = device_create_file(dev, &dev_attr_period);
210		if (err)
211			goto out3;
212	}
213	if (info->pps) {
214		err = device_create_file(dev, &dev_attr_pps_enable);
215		if (err)
216			goto out4;
217	}
218	return 0;
219out4:
220	if (info->n_per_out)
221		device_remove_file(dev, &dev_attr_period);
222out3:
223	if (info->n_ext_ts)
224		device_remove_file(dev, &dev_attr_fifo);
225out2:
226	if (info->n_ext_ts)
227		device_remove_file(dev, &dev_attr_extts_enable);
228out1:
229	return err;
230}