Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs...
[platform/adaptation/renesas_rcar/renesas_kernel.git] / drivers / ptp / ptp_sysfs.c
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
24 static 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)                                              \
32 static 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
39 PTP_SHOW_INT(max_adj);
40 PTP_SHOW_INT(n_alarm);
41 PTP_SHOW_INT(n_ext_ts);
42 PTP_SHOW_INT(n_per_out);
43 PTP_SHOW_INT(pps);
44
45 #define PTP_RO_ATTR(_var, _name) {                              \
46         .attr   = { .name = __stringify(_name), .mode = 0444 }, \
47         .show   = _var##_show,                                  \
48 }
49
50 struct 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
60 static 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;
81 out:
82         return err;
83 }
84
85 static 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);
113 out:
114         mutex_unlock(&ptp->tsevq_mux);
115         return cnt;
116 }
117
118 static 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;
141 out:
142         return err;
143 }
144
145 static 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;
167 out:
168         return err;
169 }
170
171 static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store);
172 static DEVICE_ATTR(fifo,         0444, extts_fifo_show, NULL);
173 static DEVICE_ATTR(period,       0220, NULL, period_store);
174 static DEVICE_ATTR(pps_enable,   0220, NULL, pps_enable_store);
175
176 int 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
194 int 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;
219 out4:
220         if (info->n_per_out)
221                 device_remove_file(dev, &dev_attr_period);
222 out3:
223         if (info->n_ext_ts)
224                 device_remove_file(dev, &dev_attr_fifo);
225 out2:
226         if (info->n_ext_ts)
227                 device_remove_file(dev, &dev_attr_extts_enable);
228 out1:
229         return err;
230 }