xref: /openbmc/linux/drivers/ptp/ptp_sysfs.c (revision 95298d63)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * PTP 1588 clock support - sysfs interface.
4  *
5  * Copyright (C) 2010 OMICRON electronics GmbH
6  */
7 #include <linux/capability.h>
8 #include <linux/slab.h>
9 
10 #include "ptp_private.h"
11 
12 static ssize_t clock_name_show(struct device *dev,
13 			       struct device_attribute *attr, char *page)
14 {
15 	struct ptp_clock *ptp = dev_get_drvdata(dev);
16 	return snprintf(page, PAGE_SIZE-1, "%s\n", ptp->info->name);
17 }
18 static DEVICE_ATTR_RO(clock_name);
19 
20 #define PTP_SHOW_INT(name, var)						\
21 static ssize_t var##_show(struct device *dev,				\
22 			   struct device_attribute *attr, char *page)	\
23 {									\
24 	struct ptp_clock *ptp = dev_get_drvdata(dev);			\
25 	return snprintf(page, PAGE_SIZE-1, "%d\n", ptp->info->var);	\
26 }									\
27 static DEVICE_ATTR(name, 0444, var##_show, NULL);
28 
29 PTP_SHOW_INT(max_adjustment, max_adj);
30 PTP_SHOW_INT(n_alarms, n_alarm);
31 PTP_SHOW_INT(n_external_timestamps, n_ext_ts);
32 PTP_SHOW_INT(n_periodic_outputs, n_per_out);
33 PTP_SHOW_INT(n_programmable_pins, n_pins);
34 PTP_SHOW_INT(pps_available, pps);
35 
36 static ssize_t extts_enable_store(struct device *dev,
37 				  struct device_attribute *attr,
38 				  const char *buf, size_t count)
39 {
40 	struct ptp_clock *ptp = dev_get_drvdata(dev);
41 	struct ptp_clock_info *ops = ptp->info;
42 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_EXTTS };
43 	int cnt, enable;
44 	int err = -EINVAL;
45 
46 	cnt = sscanf(buf, "%u %d", &req.extts.index, &enable);
47 	if (cnt != 2)
48 		goto out;
49 	if (req.extts.index >= ops->n_ext_ts)
50 		goto out;
51 
52 	err = ops->enable(ops, &req, enable ? 1 : 0);
53 	if (err)
54 		goto out;
55 
56 	return count;
57 out:
58 	return err;
59 }
60 static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store);
61 
62 static ssize_t extts_fifo_show(struct device *dev,
63 			       struct device_attribute *attr, char *page)
64 {
65 	struct ptp_clock *ptp = dev_get_drvdata(dev);
66 	struct timestamp_event_queue *queue = &ptp->tsevq;
67 	struct ptp_extts_event event;
68 	unsigned long flags;
69 	size_t qcnt;
70 	int cnt = 0;
71 
72 	memset(&event, 0, sizeof(event));
73 
74 	if (mutex_lock_interruptible(&ptp->tsevq_mux))
75 		return -ERESTARTSYS;
76 
77 	spin_lock_irqsave(&queue->lock, flags);
78 	qcnt = queue_cnt(queue);
79 	if (qcnt) {
80 		event = queue->buf[queue->head];
81 		queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
82 	}
83 	spin_unlock_irqrestore(&queue->lock, flags);
84 
85 	if (!qcnt)
86 		goto out;
87 
88 	cnt = snprintf(page, PAGE_SIZE, "%u %lld %u\n",
89 		       event.index, event.t.sec, event.t.nsec);
90 out:
91 	mutex_unlock(&ptp->tsevq_mux);
92 	return cnt;
93 }
94 static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL);
95 
96 static ssize_t period_store(struct device *dev,
97 			    struct device_attribute *attr,
98 			    const char *buf, size_t count)
99 {
100 	struct ptp_clock *ptp = dev_get_drvdata(dev);
101 	struct ptp_clock_info *ops = ptp->info;
102 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PEROUT };
103 	int cnt, enable, err = -EINVAL;
104 
105 	cnt = sscanf(buf, "%u %lld %u %lld %u", &req.perout.index,
106 		     &req.perout.start.sec, &req.perout.start.nsec,
107 		     &req.perout.period.sec, &req.perout.period.nsec);
108 	if (cnt != 5)
109 		goto out;
110 	if (req.perout.index >= ops->n_per_out)
111 		goto out;
112 
113 	enable = req.perout.period.sec || req.perout.period.nsec;
114 	err = ops->enable(ops, &req, enable);
115 	if (err)
116 		goto out;
117 
118 	return count;
119 out:
120 	return err;
121 }
122 static DEVICE_ATTR(period, 0220, NULL, period_store);
123 
124 static ssize_t pps_enable_store(struct device *dev,
125 				struct device_attribute *attr,
126 				const char *buf, size_t count)
127 {
128 	struct ptp_clock *ptp = dev_get_drvdata(dev);
129 	struct ptp_clock_info *ops = ptp->info;
130 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PPS };
131 	int cnt, enable;
132 	int err = -EINVAL;
133 
134 	if (!capable(CAP_SYS_TIME))
135 		return -EPERM;
136 
137 	cnt = sscanf(buf, "%d", &enable);
138 	if (cnt != 1)
139 		goto out;
140 
141 	err = ops->enable(ops, &req, enable ? 1 : 0);
142 	if (err)
143 		goto out;
144 
145 	return count;
146 out:
147 	return err;
148 }
149 static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store);
150 
151 static struct attribute *ptp_attrs[] = {
152 	&dev_attr_clock_name.attr,
153 
154 	&dev_attr_max_adjustment.attr,
155 	&dev_attr_n_alarms.attr,
156 	&dev_attr_n_external_timestamps.attr,
157 	&dev_attr_n_periodic_outputs.attr,
158 	&dev_attr_n_programmable_pins.attr,
159 	&dev_attr_pps_available.attr,
160 
161 	&dev_attr_extts_enable.attr,
162 	&dev_attr_fifo.attr,
163 	&dev_attr_period.attr,
164 	&dev_attr_pps_enable.attr,
165 	NULL
166 };
167 
168 static umode_t ptp_is_attribute_visible(struct kobject *kobj,
169 					struct attribute *attr, int n)
170 {
171 	struct device *dev = kobj_to_dev(kobj);
172 	struct ptp_clock *ptp = dev_get_drvdata(dev);
173 	struct ptp_clock_info *info = ptp->info;
174 	umode_t mode = attr->mode;
175 
176 	if (attr == &dev_attr_extts_enable.attr ||
177 	    attr == &dev_attr_fifo.attr) {
178 		if (!info->n_ext_ts)
179 			mode = 0;
180 	} else if (attr == &dev_attr_period.attr) {
181 		if (!info->n_per_out)
182 			mode = 0;
183 	} else if (attr == &dev_attr_pps_enable.attr) {
184 		if (!info->pps)
185 			mode = 0;
186 	}
187 
188 	return mode;
189 }
190 
191 static const struct attribute_group ptp_group = {
192 	.is_visible	= ptp_is_attribute_visible,
193 	.attrs		= ptp_attrs,
194 };
195 
196 const struct attribute_group *ptp_groups[] = {
197 	&ptp_group,
198 	NULL
199 };
200 
201 static int ptp_pin_name2index(struct ptp_clock *ptp, const char *name)
202 {
203 	int i;
204 	for (i = 0; i < ptp->info->n_pins; i++) {
205 		if (!strcmp(ptp->info->pin_config[i].name, name))
206 			return i;
207 	}
208 	return -1;
209 }
210 
211 static ssize_t ptp_pin_show(struct device *dev, struct device_attribute *attr,
212 			    char *page)
213 {
214 	struct ptp_clock *ptp = dev_get_drvdata(dev);
215 	unsigned int func, chan;
216 	int index;
217 
218 	index = ptp_pin_name2index(ptp, attr->attr.name);
219 	if (index < 0)
220 		return -EINVAL;
221 
222 	if (mutex_lock_interruptible(&ptp->pincfg_mux))
223 		return -ERESTARTSYS;
224 
225 	func = ptp->info->pin_config[index].func;
226 	chan = ptp->info->pin_config[index].chan;
227 
228 	mutex_unlock(&ptp->pincfg_mux);
229 
230 	return snprintf(page, PAGE_SIZE, "%u %u\n", func, chan);
231 }
232 
233 static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr,
234 			     const char *buf, size_t count)
235 {
236 	struct ptp_clock *ptp = dev_get_drvdata(dev);
237 	unsigned int func, chan;
238 	int cnt, err, index;
239 
240 	cnt = sscanf(buf, "%u %u", &func, &chan);
241 	if (cnt != 2)
242 		return -EINVAL;
243 
244 	index = ptp_pin_name2index(ptp, attr->attr.name);
245 	if (index < 0)
246 		return -EINVAL;
247 
248 	if (mutex_lock_interruptible(&ptp->pincfg_mux))
249 		return -ERESTARTSYS;
250 	err = ptp_set_pinfunc(ptp, index, func, chan);
251 	mutex_unlock(&ptp->pincfg_mux);
252 	if (err)
253 		return err;
254 
255 	return count;
256 }
257 
258 int ptp_populate_pin_groups(struct ptp_clock *ptp)
259 {
260 	struct ptp_clock_info *info = ptp->info;
261 	int err = -ENOMEM, i, n_pins = info->n_pins;
262 
263 	if (!n_pins)
264 		return 0;
265 
266 	ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr),
267 				    GFP_KERNEL);
268 	if (!ptp->pin_dev_attr)
269 		goto no_dev_attr;
270 
271 	ptp->pin_attr = kcalloc(1 + n_pins, sizeof(*ptp->pin_attr), GFP_KERNEL);
272 	if (!ptp->pin_attr)
273 		goto no_pin_attr;
274 
275 	for (i = 0; i < n_pins; i++) {
276 		struct device_attribute *da = &ptp->pin_dev_attr[i];
277 		sysfs_attr_init(&da->attr);
278 		da->attr.name = info->pin_config[i].name;
279 		da->attr.mode = 0644;
280 		da->show = ptp_pin_show;
281 		da->store = ptp_pin_store;
282 		ptp->pin_attr[i] = &da->attr;
283 	}
284 
285 	ptp->pin_attr_group.name = "pins";
286 	ptp->pin_attr_group.attrs = ptp->pin_attr;
287 
288 	ptp->pin_attr_groups[0] = &ptp->pin_attr_group;
289 
290 	return 0;
291 
292 no_pin_attr:
293 	kfree(ptp->pin_dev_attr);
294 no_dev_attr:
295 	return err;
296 }
297 
298 void ptp_cleanup_pin_groups(struct ptp_clock *ptp)
299 {
300 	kfree(ptp->pin_attr);
301 	kfree(ptp->pin_dev_attr);
302 }
303