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
clock_name_show(struct device * dev,struct device_attribute * attr,char * page)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 sysfs_emit(page, "%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
extts_enable_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)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
extts_fifo_show(struct device * dev,struct device_attribute * attr,char * page)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 /* Paired with READ_ONCE() in queue_cnt() */
82 WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
83 }
84 spin_unlock_irqrestore(&queue->lock, flags);
85
86 if (!qcnt)
87 goto out;
88
89 cnt = snprintf(page, PAGE_SIZE, "%u %lld %u\n",
90 event.index, event.t.sec, event.t.nsec);
91 out:
92 mutex_unlock(&ptp->tsevq_mux);
93 return cnt;
94 }
95 static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL);
96
period_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)97 static ssize_t period_store(struct device *dev,
98 struct device_attribute *attr,
99 const char *buf, size_t count)
100 {
101 struct ptp_clock *ptp = dev_get_drvdata(dev);
102 struct ptp_clock_info *ops = ptp->info;
103 struct ptp_clock_request req = { .type = PTP_CLK_REQ_PEROUT };
104 int cnt, enable, err = -EINVAL;
105
106 cnt = sscanf(buf, "%u %lld %u %lld %u", &req.perout.index,
107 &req.perout.start.sec, &req.perout.start.nsec,
108 &req.perout.period.sec, &req.perout.period.nsec);
109 if (cnt != 5)
110 goto out;
111 if (req.perout.index >= ops->n_per_out)
112 goto out;
113
114 enable = req.perout.period.sec || req.perout.period.nsec;
115 err = ops->enable(ops, &req, enable);
116 if (err)
117 goto out;
118
119 return count;
120 out:
121 return err;
122 }
123 static DEVICE_ATTR(period, 0220, NULL, period_store);
124
pps_enable_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)125 static ssize_t pps_enable_store(struct device *dev,
126 struct device_attribute *attr,
127 const char *buf, size_t count)
128 {
129 struct ptp_clock *ptp = dev_get_drvdata(dev);
130 struct ptp_clock_info *ops = ptp->info;
131 struct ptp_clock_request req = { .type = PTP_CLK_REQ_PPS };
132 int cnt, enable;
133 int err = -EINVAL;
134
135 if (!capable(CAP_SYS_TIME))
136 return -EPERM;
137
138 cnt = sscanf(buf, "%d", &enable);
139 if (cnt != 1)
140 goto out;
141
142 err = ops->enable(ops, &req, enable ? 1 : 0);
143 if (err)
144 goto out;
145
146 return count;
147 out:
148 return err;
149 }
150 static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store);
151
152 static struct attribute *ptp_attrs[] = {
153 &dev_attr_clock_name.attr,
154
155 &dev_attr_max_adjustment.attr,
156 &dev_attr_n_alarms.attr,
157 &dev_attr_n_external_timestamps.attr,
158 &dev_attr_n_periodic_outputs.attr,
159 &dev_attr_n_programmable_pins.attr,
160 &dev_attr_pps_available.attr,
161
162 &dev_attr_extts_enable.attr,
163 &dev_attr_fifo.attr,
164 &dev_attr_period.attr,
165 &dev_attr_pps_enable.attr,
166 NULL
167 };
168
ptp_is_attribute_visible(struct kobject * kobj,struct attribute * attr,int n)169 static umode_t ptp_is_attribute_visible(struct kobject *kobj,
170 struct attribute *attr, int n)
171 {
172 struct device *dev = kobj_to_dev(kobj);
173 struct ptp_clock *ptp = dev_get_drvdata(dev);
174 struct ptp_clock_info *info = ptp->info;
175 umode_t mode = attr->mode;
176
177 if (attr == &dev_attr_extts_enable.attr ||
178 attr == &dev_attr_fifo.attr) {
179 if (!info->n_ext_ts)
180 mode = 0;
181 } else if (attr == &dev_attr_period.attr) {
182 if (!info->n_per_out)
183 mode = 0;
184 } else if (attr == &dev_attr_pps_enable.attr) {
185 if (!info->pps)
186 mode = 0;
187 }
188
189 return mode;
190 }
191
192 static const struct attribute_group ptp_group = {
193 .is_visible = ptp_is_attribute_visible,
194 .attrs = ptp_attrs,
195 };
196
197 const struct attribute_group *ptp_groups[] = {
198 &ptp_group,
199 NULL
200 };
201
ptp_pin_name2index(struct ptp_clock * ptp,const char * name)202 static int ptp_pin_name2index(struct ptp_clock *ptp, const char *name)
203 {
204 int i;
205 for (i = 0; i < ptp->info->n_pins; i++) {
206 if (!strcmp(ptp->info->pin_config[i].name, name))
207 return i;
208 }
209 return -1;
210 }
211
ptp_pin_show(struct device * dev,struct device_attribute * attr,char * page)212 static ssize_t ptp_pin_show(struct device *dev, struct device_attribute *attr,
213 char *page)
214 {
215 struct ptp_clock *ptp = dev_get_drvdata(dev);
216 unsigned int func, chan;
217 int index;
218
219 index = ptp_pin_name2index(ptp, attr->attr.name);
220 if (index < 0)
221 return -EINVAL;
222
223 if (mutex_lock_interruptible(&ptp->pincfg_mux))
224 return -ERESTARTSYS;
225
226 func = ptp->info->pin_config[index].func;
227 chan = ptp->info->pin_config[index].chan;
228
229 mutex_unlock(&ptp->pincfg_mux);
230
231 return sysfs_emit(page, "%u %u\n", func, chan);
232 }
233
ptp_pin_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)234 static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr,
235 const char *buf, size_t count)
236 {
237 struct ptp_clock *ptp = dev_get_drvdata(dev);
238 unsigned int func, chan;
239 int cnt, err, index;
240
241 cnt = sscanf(buf, "%u %u", &func, &chan);
242 if (cnt != 2)
243 return -EINVAL;
244
245 index = ptp_pin_name2index(ptp, attr->attr.name);
246 if (index < 0)
247 return -EINVAL;
248
249 if (mutex_lock_interruptible(&ptp->pincfg_mux))
250 return -ERESTARTSYS;
251 err = ptp_set_pinfunc(ptp, index, func, chan);
252 mutex_unlock(&ptp->pincfg_mux);
253 if (err)
254 return err;
255
256 return count;
257 }
258
ptp_populate_pin_groups(struct ptp_clock * ptp)259 int ptp_populate_pin_groups(struct ptp_clock *ptp)
260 {
261 struct ptp_clock_info *info = ptp->info;
262 int err = -ENOMEM, i, n_pins = info->n_pins;
263
264 if (!n_pins)
265 return 0;
266
267 ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr),
268 GFP_KERNEL);
269 if (!ptp->pin_dev_attr)
270 goto no_dev_attr;
271
272 ptp->pin_attr = kcalloc(1 + n_pins, sizeof(*ptp->pin_attr), GFP_KERNEL);
273 if (!ptp->pin_attr)
274 goto no_pin_attr;
275
276 for (i = 0; i < n_pins; i++) {
277 struct device_attribute *da = &ptp->pin_dev_attr[i];
278 sysfs_attr_init(&da->attr);
279 da->attr.name = info->pin_config[i].name;
280 da->attr.mode = 0644;
281 da->show = ptp_pin_show;
282 da->store = ptp_pin_store;
283 ptp->pin_attr[i] = &da->attr;
284 }
285
286 ptp->pin_attr_group.name = "pins";
287 ptp->pin_attr_group.attrs = ptp->pin_attr;
288
289 ptp->pin_attr_groups[0] = &ptp->pin_attr_group;
290
291 return 0;
292
293 no_pin_attr:
294 kfree(ptp->pin_dev_attr);
295 no_dev_attr:
296 return err;
297 }
298
ptp_cleanup_pin_groups(struct ptp_clock * ptp)299 void ptp_cleanup_pin_groups(struct ptp_clock *ptp)
300 {
301 kfree(ptp->pin_attr);
302 kfree(ptp->pin_dev_attr);
303 }
304