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23#include <linux/kernel.h>
24#include <linux/module.h>
25#include <linux/init.h>
26#include <linux/sched.h>
27#include <linux/uaccess.h>
28#include <linux/idr.h>
29#include <linux/cdev.h>
30#include <linux/poll.h>
31#include <linux/pps_kernel.h>
32
33
34
35
36
37static dev_t pps_devt;
38static struct class *pps_class;
39
40
41
42
43
44static unsigned int pps_cdev_poll(struct file *file, poll_table *wait)
45{
46 struct pps_device *pps = file->private_data;
47
48 poll_wait(file, &pps->queue, wait);
49
50 return POLLIN | POLLRDNORM;
51}
52
53static int pps_cdev_fasync(int fd, struct file *file, int on)
54{
55 struct pps_device *pps = file->private_data;
56 return fasync_helper(fd, file, on, &pps->async_queue);
57}
58
59static long pps_cdev_ioctl(struct file *file,
60 unsigned int cmd, unsigned long arg)
61{
62 struct pps_device *pps = file->private_data;
63 struct pps_kparams params;
64 struct pps_fdata fdata;
65 unsigned long ticks;
66 void __user *uarg = (void __user *) arg;
67 int __user *iuarg = (int __user *) arg;
68 int err;
69
70 switch (cmd) {
71 case PPS_GETPARAMS:
72 pr_debug("PPS_GETPARAMS: source %d\n", pps->id);
73
74 spin_lock_irq(&pps->lock);
75
76
77 params = pps->params;
78
79 spin_unlock_irq(&pps->lock);
80
81 err = copy_to_user(uarg, ¶ms, sizeof(struct pps_kparams));
82 if (err)
83 return -EFAULT;
84
85 break;
86
87 case PPS_SETPARAMS:
88 pr_debug("PPS_SETPARAMS: source %d\n", pps->id);
89
90
91 if (!capable(CAP_SYS_TIME))
92 return -EPERM;
93
94 err = copy_from_user(¶ms, uarg, sizeof(struct pps_kparams));
95 if (err)
96 return -EFAULT;
97 if (!(params.mode & (PPS_CAPTUREASSERT | PPS_CAPTURECLEAR))) {
98 pr_debug("capture mode unspecified (%x)\n",
99 params.mode);
100 return -EINVAL;
101 }
102
103
104 if ((params.mode & ~pps->info.mode) != 0) {
105 pr_debug("unsupported capabilities (%x)\n",
106 params.mode);
107 return -EINVAL;
108 }
109
110 spin_lock_irq(&pps->lock);
111
112
113 pps->params = params;
114
115
116 if ((params.mode & (PPS_TSFMT_TSPEC | PPS_TSFMT_NTPFP)) == 0) {
117
118 pr_debug("time format unspecified (%x)\n",
119 params.mode);
120 pps->params.mode |= PPS_TSFMT_TSPEC;
121 }
122 if (pps->info.mode & PPS_CANWAIT)
123 pps->params.mode |= PPS_CANWAIT;
124 pps->params.api_version = PPS_API_VERS;
125
126 spin_unlock_irq(&pps->lock);
127
128 break;
129
130 case PPS_GETCAP:
131 pr_debug("PPS_GETCAP: source %d\n", pps->id);
132
133 err = put_user(pps->info.mode, iuarg);
134 if (err)
135 return -EFAULT;
136
137 break;
138
139 case PPS_FETCH:
140 pr_debug("PPS_FETCH: source %d\n", pps->id);
141
142 err = copy_from_user(&fdata, uarg, sizeof(struct pps_fdata));
143 if (err)
144 return -EFAULT;
145
146 pps->go = 0;
147
148
149 if (fdata.timeout.flags & PPS_TIME_INVALID)
150 err = wait_event_interruptible(pps->queue, pps->go);
151 else {
152 pr_debug("timeout %lld.%09d\n",
153 (long long) fdata.timeout.sec,
154 fdata.timeout.nsec);
155 ticks = fdata.timeout.sec * HZ;
156 ticks += fdata.timeout.nsec / (NSEC_PER_SEC / HZ);
157
158 if (ticks != 0) {
159 err = wait_event_interruptible_timeout(
160 pps->queue, pps->go, ticks);
161 if (err == 0)
162 return -ETIMEDOUT;
163 }
164 }
165
166
167 if (err == -ERESTARTSYS) {
168 pr_debug("pending signal caught\n");
169 return -EINTR;
170 }
171
172
173 spin_lock_irq(&pps->lock);
174
175 fdata.info.assert_sequence = pps->assert_sequence;
176 fdata.info.clear_sequence = pps->clear_sequence;
177 fdata.info.assert_tu = pps->assert_tu;
178 fdata.info.clear_tu = pps->clear_tu;
179 fdata.info.current_mode = pps->current_mode;
180
181 spin_unlock_irq(&pps->lock);
182
183 err = copy_to_user(uarg, &fdata, sizeof(struct pps_fdata));
184 if (err)
185 return -EFAULT;
186
187 break;
188
189 default:
190 return -ENOTTY;
191 break;
192 }
193
194 return 0;
195}
196
197static int pps_cdev_open(struct inode *inode, struct file *file)
198{
199 struct pps_device *pps = container_of(inode->i_cdev,
200 struct pps_device, cdev);
201 int found;
202
203 found = pps_get_source(pps->id) != 0;
204 if (!found)
205 return -ENODEV;
206
207 file->private_data = pps;
208
209 return 0;
210}
211
212static int pps_cdev_release(struct inode *inode, struct file *file)
213{
214 struct pps_device *pps = file->private_data;
215
216
217 pps_put_source(pps);
218
219 return 0;
220}
221
222
223
224
225
226static const struct file_operations pps_cdev_fops = {
227 .owner = THIS_MODULE,
228 .llseek = no_llseek,
229 .poll = pps_cdev_poll,
230 .fasync = pps_cdev_fasync,
231 .unlocked_ioctl = pps_cdev_ioctl,
232 .open = pps_cdev_open,
233 .release = pps_cdev_release,
234};
235
236int pps_register_cdev(struct pps_device *pps)
237{
238 int err;
239
240 pps->devno = MKDEV(MAJOR(pps_devt), pps->id);
241 cdev_init(&pps->cdev, &pps_cdev_fops);
242 pps->cdev.owner = pps->info.owner;
243
244 err = cdev_add(&pps->cdev, pps->devno, 1);
245 if (err) {
246 printk(KERN_ERR "pps: %s: failed to add char device %d:%d\n",
247 pps->info.name, MAJOR(pps_devt), pps->id);
248 return err;
249 }
250 pps->dev = device_create(pps_class, pps->info.dev, pps->devno, NULL,
251 "pps%d", pps->id);
252 if (IS_ERR(pps->dev))
253 goto del_cdev;
254 dev_set_drvdata(pps->dev, pps);
255
256 pr_debug("source %s got cdev (%d:%d)\n", pps->info.name,
257 MAJOR(pps_devt), pps->id);
258
259 return 0;
260
261del_cdev:
262 cdev_del(&pps->cdev);
263
264 return err;
265}
266
267void pps_unregister_cdev(struct pps_device *pps)
268{
269 device_destroy(pps_class, pps->devno);
270 cdev_del(&pps->cdev);
271}
272
273
274
275
276
277static void __exit pps_exit(void)
278{
279 class_destroy(pps_class);
280 unregister_chrdev_region(pps_devt, PPS_MAX_SOURCES);
281}
282
283static int __init pps_init(void)
284{
285 int err;
286
287 pps_class = class_create(THIS_MODULE, "pps");
288 if (!pps_class) {
289 printk(KERN_ERR "pps: failed to allocate class\n");
290 return -ENOMEM;
291 }
292 pps_class->dev_attrs = pps_attrs;
293
294 err = alloc_chrdev_region(&pps_devt, 0, PPS_MAX_SOURCES, "pps");
295 if (err < 0) {
296 printk(KERN_ERR "pps: failed to allocate char device region\n");
297 goto remove_class;
298 }
299
300 pr_info("LinuxPPS API ver. %d registered\n", PPS_API_VERS);
301 pr_info("Software ver. %s - Copyright 2005-2007 Rodolfo Giometti "
302 "<giometti@linux.it>\n", PPS_VERSION);
303
304 return 0;
305
306remove_class:
307 class_destroy(pps_class);
308
309 return err;
310}
311
312subsys_initcall(pps_init);
313module_exit(pps_exit);
314
315MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
316MODULE_DESCRIPTION("LinuxPPS support (RFC 2783) - ver. " PPS_VERSION);
317MODULE_LICENSE("GPL");
318
