xref: /openbmc/linux/drivers/ptp/ptp_sysfs.c (revision 8730046c)
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 #include <linux/slab.h>
22 
23 #include "ptp_private.h"
24 
25 static ssize_t clock_name_show(struct device *dev,
26 			       struct device_attribute *attr, char *page)
27 {
28 	struct ptp_clock *ptp = dev_get_drvdata(dev);
29 	return snprintf(page, PAGE_SIZE-1, "%s\n", ptp->info->name);
30 }
31 static DEVICE_ATTR_RO(clock_name);
32 
33 #define PTP_SHOW_INT(name, var)						\
34 static ssize_t var##_show(struct device *dev,				\
35 			   struct device_attribute *attr, char *page)	\
36 {									\
37 	struct ptp_clock *ptp = dev_get_drvdata(dev);			\
38 	return snprintf(page, PAGE_SIZE-1, "%d\n", ptp->info->var);	\
39 }									\
40 static DEVICE_ATTR(name, 0444, var##_show, NULL);
41 
42 PTP_SHOW_INT(max_adjustment, max_adj);
43 PTP_SHOW_INT(n_alarms, n_alarm);
44 PTP_SHOW_INT(n_external_timestamps, n_ext_ts);
45 PTP_SHOW_INT(n_periodic_outputs, n_per_out);
46 PTP_SHOW_INT(n_programmable_pins, n_pins);
47 PTP_SHOW_INT(pps_available, pps);
48 
49 static struct attribute *ptp_attrs[] = {
50 	&dev_attr_clock_name.attr,
51 	&dev_attr_max_adjustment.attr,
52 	&dev_attr_n_alarms.attr,
53 	&dev_attr_n_external_timestamps.attr,
54 	&dev_attr_n_periodic_outputs.attr,
55 	&dev_attr_n_programmable_pins.attr,
56 	&dev_attr_pps_available.attr,
57 	NULL,
58 };
59 
60 static const struct attribute_group ptp_group = {
61 	.attrs = ptp_attrs,
62 };
63 
64 const struct attribute_group *ptp_groups[] = {
65 	&ptp_group,
66 	NULL,
67 };
68 
69 
70 static ssize_t extts_enable_store(struct device *dev,
71 				  struct device_attribute *attr,
72 				  const char *buf, size_t count)
73 {
74 	struct ptp_clock *ptp = dev_get_drvdata(dev);
75 	struct ptp_clock_info *ops = ptp->info;
76 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_EXTTS };
77 	int cnt, enable;
78 	int err = -EINVAL;
79 
80 	cnt = sscanf(buf, "%u %d", &req.extts.index, &enable);
81 	if (cnt != 2)
82 		goto out;
83 	if (req.extts.index >= ops->n_ext_ts)
84 		goto out;
85 
86 	err = ops->enable(ops, &req, enable ? 1 : 0);
87 	if (err)
88 		goto out;
89 
90 	return count;
91 out:
92 	return err;
93 }
94 
95 static ssize_t extts_fifo_show(struct device *dev,
96 			       struct device_attribute *attr, char *page)
97 {
98 	struct ptp_clock *ptp = dev_get_drvdata(dev);
99 	struct timestamp_event_queue *queue = &ptp->tsevq;
100 	struct ptp_extts_event event;
101 	unsigned long flags;
102 	size_t qcnt;
103 	int cnt = 0;
104 
105 	memset(&event, 0, sizeof(event));
106 
107 	if (mutex_lock_interruptible(&ptp->tsevq_mux))
108 		return -ERESTARTSYS;
109 
110 	spin_lock_irqsave(&queue->lock, flags);
111 	qcnt = queue_cnt(queue);
112 	if (qcnt) {
113 		event = queue->buf[queue->head];
114 		queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
115 	}
116 	spin_unlock_irqrestore(&queue->lock, flags);
117 
118 	if (!qcnt)
119 		goto out;
120 
121 	cnt = snprintf(page, PAGE_SIZE, "%u %lld %u\n",
122 		       event.index, event.t.sec, event.t.nsec);
123 out:
124 	mutex_unlock(&ptp->tsevq_mux);
125 	return cnt;
126 }
127 
128 static ssize_t period_store(struct device *dev,
129 			    struct device_attribute *attr,
130 			    const char *buf, size_t count)
131 {
132 	struct ptp_clock *ptp = dev_get_drvdata(dev);
133 	struct ptp_clock_info *ops = ptp->info;
134 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PEROUT };
135 	int cnt, enable, err = -EINVAL;
136 
137 	cnt = sscanf(buf, "%u %lld %u %lld %u", &req.perout.index,
138 		     &req.perout.start.sec, &req.perout.start.nsec,
139 		     &req.perout.period.sec, &req.perout.period.nsec);
140 	if (cnt != 5)
141 		goto out;
142 	if (req.perout.index >= ops->n_per_out)
143 		goto out;
144 
145 	enable = req.perout.period.sec || req.perout.period.nsec;
146 	err = ops->enable(ops, &req, enable);
147 	if (err)
148 		goto out;
149 
150 	return count;
151 out:
152 	return err;
153 }
154 
155 static ssize_t pps_enable_store(struct device *dev,
156 				struct device_attribute *attr,
157 				const char *buf, size_t count)
158 {
159 	struct ptp_clock *ptp = dev_get_drvdata(dev);
160 	struct ptp_clock_info *ops = ptp->info;
161 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PPS };
162 	int cnt, enable;
163 	int err = -EINVAL;
164 
165 	if (!capable(CAP_SYS_TIME))
166 		return -EPERM;
167 
168 	cnt = sscanf(buf, "%d", &enable);
169 	if (cnt != 1)
170 		goto out;
171 
172 	err = ops->enable(ops, &req, enable ? 1 : 0);
173 	if (err)
174 		goto out;
175 
176 	return count;
177 out:
178 	return err;
179 }
180 
181 static int ptp_pin_name2index(struct ptp_clock *ptp, const char *name)
182 {
183 	int i;
184 	for (i = 0; i < ptp->info->n_pins; i++) {
185 		if (!strcmp(ptp->info->pin_config[i].name, name))
186 			return i;
187 	}
188 	return -1;
189 }
190 
191 static ssize_t ptp_pin_show(struct device *dev, struct device_attribute *attr,
192 			    char *page)
193 {
194 	struct ptp_clock *ptp = dev_get_drvdata(dev);
195 	unsigned int func, chan;
196 	int index;
197 
198 	index = ptp_pin_name2index(ptp, attr->attr.name);
199 	if (index < 0)
200 		return -EINVAL;
201 
202 	if (mutex_lock_interruptible(&ptp->pincfg_mux))
203 		return -ERESTARTSYS;
204 
205 	func = ptp->info->pin_config[index].func;
206 	chan = ptp->info->pin_config[index].chan;
207 
208 	mutex_unlock(&ptp->pincfg_mux);
209 
210 	return snprintf(page, PAGE_SIZE, "%u %u\n", func, chan);
211 }
212 
213 static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr,
214 			     const char *buf, size_t count)
215 {
216 	struct ptp_clock *ptp = dev_get_drvdata(dev);
217 	unsigned int func, chan;
218 	int cnt, err, index;
219 
220 	cnt = sscanf(buf, "%u %u", &func, &chan);
221 	if (cnt != 2)
222 		return -EINVAL;
223 
224 	index = ptp_pin_name2index(ptp, attr->attr.name);
225 	if (index < 0)
226 		return -EINVAL;
227 
228 	if (mutex_lock_interruptible(&ptp->pincfg_mux))
229 		return -ERESTARTSYS;
230 	err = ptp_set_pinfunc(ptp, index, func, chan);
231 	mutex_unlock(&ptp->pincfg_mux);
232 	if (err)
233 		return err;
234 
235 	return count;
236 }
237 
238 static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store);
239 static DEVICE_ATTR(fifo,         0444, extts_fifo_show, NULL);
240 static DEVICE_ATTR(period,       0220, NULL, period_store);
241 static DEVICE_ATTR(pps_enable,   0220, NULL, pps_enable_store);
242 
243 int ptp_cleanup_sysfs(struct ptp_clock *ptp)
244 {
245 	struct device *dev = ptp->dev;
246 	struct ptp_clock_info *info = ptp->info;
247 
248 	if (info->n_ext_ts) {
249 		device_remove_file(dev, &dev_attr_extts_enable);
250 		device_remove_file(dev, &dev_attr_fifo);
251 	}
252 	if (info->n_per_out)
253 		device_remove_file(dev, &dev_attr_period);
254 
255 	if (info->pps)
256 		device_remove_file(dev, &dev_attr_pps_enable);
257 
258 	if (info->n_pins) {
259 		sysfs_remove_group(&dev->kobj, &ptp->pin_attr_group);
260 		kfree(ptp->pin_attr);
261 		kfree(ptp->pin_dev_attr);
262 	}
263 	return 0;
264 }
265 
266 static int ptp_populate_pins(struct ptp_clock *ptp)
267 {
268 	struct device *dev = ptp->dev;
269 	struct ptp_clock_info *info = ptp->info;
270 	int err = -ENOMEM, i, n_pins = info->n_pins;
271 
272 	ptp->pin_dev_attr = kzalloc(n_pins * sizeof(*ptp->pin_dev_attr),
273 				    GFP_KERNEL);
274 	if (!ptp->pin_dev_attr)
275 		goto no_dev_attr;
276 
277 	ptp->pin_attr = kzalloc((1 + n_pins) * sizeof(struct attribute *),
278 				GFP_KERNEL);
279 	if (!ptp->pin_attr)
280 		goto no_pin_attr;
281 
282 	for (i = 0; i < n_pins; i++) {
283 		struct device_attribute *da = &ptp->pin_dev_attr[i];
284 		sysfs_attr_init(&da->attr);
285 		da->attr.name = info->pin_config[i].name;
286 		da->attr.mode = 0644;
287 		da->show = ptp_pin_show;
288 		da->store = ptp_pin_store;
289 		ptp->pin_attr[i] = &da->attr;
290 	}
291 
292 	ptp->pin_attr_group.name = "pins";
293 	ptp->pin_attr_group.attrs = ptp->pin_attr;
294 
295 	err = sysfs_create_group(&dev->kobj, &ptp->pin_attr_group);
296 	if (err)
297 		goto no_group;
298 	return 0;
299 
300 no_group:
301 	kfree(ptp->pin_attr);
302 no_pin_attr:
303 	kfree(ptp->pin_dev_attr);
304 no_dev_attr:
305 	return err;
306 }
307 
308 int ptp_populate_sysfs(struct ptp_clock *ptp)
309 {
310 	struct device *dev = ptp->dev;
311 	struct ptp_clock_info *info = ptp->info;
312 	int err;
313 
314 	if (info->n_ext_ts) {
315 		err = device_create_file(dev, &dev_attr_extts_enable);
316 		if (err)
317 			goto out1;
318 		err = device_create_file(dev, &dev_attr_fifo);
319 		if (err)
320 			goto out2;
321 	}
322 	if (info->n_per_out) {
323 		err = device_create_file(dev, &dev_attr_period);
324 		if (err)
325 			goto out3;
326 	}
327 	if (info->pps) {
328 		err = device_create_file(dev, &dev_attr_pps_enable);
329 		if (err)
330 			goto out4;
331 	}
332 	if (info->n_pins) {
333 		err = ptp_populate_pins(ptp);
334 		if (err)
335 			goto out5;
336 	}
337 	return 0;
338 out5:
339 	if (info->pps)
340 		device_remove_file(dev, &dev_attr_pps_enable);
341 out4:
342 	if (info->n_per_out)
343 		device_remove_file(dev, &dev_attr_period);
344 out3:
345 	if (info->n_ext_ts)
346 		device_remove_file(dev, &dev_attr_fifo);
347 out2:
348 	if (info->n_ext_ts)
349 		device_remove_file(dev, &dev_attr_extts_enable);
350 out1:
351 	return err;
352 }
353