1 /* -----------------------------------------------------------------------------
2 * Copyright (c) 2011 Ozmo Inc
3 * Released under the GNU General Public License Version 2 (GPLv2).
4 * -----------------------------------------------------------------------------
5 */
6 #include <linux/module.h>
7 #include <linux/fs.h>
8 #include <linux/cdev.h>
9 #include <linux/uaccess.h>
10 #include <linux/netdevice.h>
11 #include <linux/poll.h>
12 #include <linux/sched.h>
13 #include "ozconfig.h"
14 #include "ozprotocol.h"
15 #include "oztrace.h"
16 #include "ozappif.h"
17 #include "ozeltbuf.h"
18 #include "ozpd.h"
19 #include "ozproto.h"
20 #include "ozevent.h"
21 /*------------------------------------------------------------------------------
22 */
23 #define OZ_RD_BUF_SZ 256
24 struct oz_cdev {
25 dev_t devnum;
26 struct cdev cdev;
27 wait_queue_head_t rdq;
28 spinlock_t lock;
29 u8 active_addr[ETH_ALEN];
30 struct oz_pd *active_pd;
31 };
32
33 /* Per PD context for the serial service stored in the PD. */
34 struct oz_serial_ctx {
35 atomic_t ref_count;
36 u8 tx_seq_num;
37 u8 rx_seq_num;
38 u8 rd_buf[OZ_RD_BUF_SZ];
39 int rd_in;
40 int rd_out;
41 };
42 /*------------------------------------------------------------------------------
43 */
44 int g_taction;
45 /*------------------------------------------------------------------------------
46 */
47 static struct oz_cdev g_cdev;
48 /*------------------------------------------------------------------------------
49 * Context: process and softirq
50 */
oz_cdev_claim_ctx(struct oz_pd * pd)51 static struct oz_serial_ctx *oz_cdev_claim_ctx(struct oz_pd *pd)
52 {
53 struct oz_serial_ctx *ctx;
54 spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
55 ctx = (struct oz_serial_ctx *)pd->app_ctx[OZ_APPID_SERIAL-1];
56 if (ctx)
57 atomic_inc(&ctx->ref_count);
58 spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
59 return ctx;
60 }
61 /*------------------------------------------------------------------------------
62 * Context: softirq or process
63 */
oz_cdev_release_ctx(struct oz_serial_ctx * ctx)64 static void oz_cdev_release_ctx(struct oz_serial_ctx *ctx)
65 {
66 if (atomic_dec_and_test(&ctx->ref_count)) {
67 oz_trace("Dealloc serial context.\n");
68 kfree(ctx);
69 }
70 }
71 /*------------------------------------------------------------------------------
72 * Context: process
73 */
oz_cdev_open(struct inode * inode,struct file * filp)74 int oz_cdev_open(struct inode *inode, struct file *filp)
75 {
76 struct oz_cdev *dev;
77 oz_trace("oz_cdev_open()\n");
78 oz_trace("major = %d minor = %d\n", imajor(inode), iminor(inode));
79 dev = container_of(inode->i_cdev, struct oz_cdev, cdev);
80 filp->private_data = dev;
81 return 0;
82 }
83 /*------------------------------------------------------------------------------
84 * Context: process
85 */
oz_cdev_release(struct inode * inode,struct file * filp)86 int oz_cdev_release(struct inode *inode, struct file *filp)
87 {
88 oz_trace("oz_cdev_release()\n");
89 return 0;
90 }
91 /*------------------------------------------------------------------------------
92 * Context: process
93 */
oz_cdev_read(struct file * filp,char __user * buf,size_t count,loff_t * fpos)94 ssize_t oz_cdev_read(struct file *filp, char __user *buf, size_t count,
95 loff_t *fpos)
96 {
97 int n;
98 int ix;
99
100 struct oz_pd *pd;
101 struct oz_serial_ctx *ctx = 0;
102
103 spin_lock_bh(&g_cdev.lock);
104 pd = g_cdev.active_pd;
105 if (pd)
106 oz_pd_get(pd);
107 spin_unlock_bh(&g_cdev.lock);
108 if (pd == 0)
109 return -1;
110 ctx = oz_cdev_claim_ctx(pd);
111 if (ctx == 0)
112 goto out2;
113 n = ctx->rd_in - ctx->rd_out;
114 if (n < 0)
115 n += OZ_RD_BUF_SZ;
116 if (count > n)
117 count = n;
118 ix = ctx->rd_out;
119 n = OZ_RD_BUF_SZ - ix;
120 if (n > count)
121 n = count;
122 if (copy_to_user(buf, &ctx->rd_buf[ix], n)) {
123 count = 0;
124 goto out1;
125 }
126 ix += n;
127 if (ix == OZ_RD_BUF_SZ)
128 ix = 0;
129 if (n < count) {
130 if (copy_to_user(&buf[n], ctx->rd_buf, count-n)) {
131 count = 0;
132 goto out1;
133 }
134 ix = count-n;
135 }
136 ctx->rd_out = ix;
137 out1:
138 oz_cdev_release_ctx(ctx);
139 out2:
140 oz_pd_put(pd);
141 return count;
142 }
143 /*------------------------------------------------------------------------------
144 * Context: process
145 */
oz_cdev_write(struct file * filp,const char __user * buf,size_t count,loff_t * fpos)146 ssize_t oz_cdev_write(struct file *filp, const char __user *buf, size_t count,
147 loff_t *fpos)
148 {
149 struct oz_pd *pd;
150 struct oz_elt_buf *eb;
151 struct oz_elt_info *ei = 0;
152 struct oz_elt *elt;
153 struct oz_app_hdr *app_hdr;
154 struct oz_serial_ctx *ctx;
155
156 spin_lock_bh(&g_cdev.lock);
157 pd = g_cdev.active_pd;
158 if (pd)
159 oz_pd_get(pd);
160 spin_unlock_bh(&g_cdev.lock);
161 if (pd == 0)
162 return -1;
163 eb = &pd->elt_buff;
164 ei = oz_elt_info_alloc(eb);
165 if (ei == 0) {
166 count = 0;
167 goto out;
168 }
169 elt = (struct oz_elt *)ei->data;
170 app_hdr = (struct oz_app_hdr *)(elt+1);
171 elt->length = sizeof(struct oz_app_hdr) + count;
172 elt->type = OZ_ELT_APP_DATA;
173 ei->app_id = OZ_APPID_SERIAL;
174 ei->length = elt->length + sizeof(struct oz_elt);
175 app_hdr->app_id = OZ_APPID_SERIAL;
176 if (copy_from_user(app_hdr+1, buf, count))
177 goto out;
178 spin_lock_bh(&pd->app_lock[OZ_APPID_USB-1]);
179 ctx = (struct oz_serial_ctx *)pd->app_ctx[OZ_APPID_SERIAL-1];
180 if (ctx) {
181 app_hdr->elt_seq_num = ctx->tx_seq_num++;
182 if (ctx->tx_seq_num == 0)
183 ctx->tx_seq_num = 1;
184 spin_lock(&eb->lock);
185 if (oz_queue_elt_info(eb, 0, 0, ei) == 0)
186 ei = 0;
187 spin_unlock(&eb->lock);
188 }
189 spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
190 out:
191 if (ei) {
192 count = 0;
193 spin_lock_bh(&eb->lock);
194 oz_elt_info_free(eb, ei);
195 spin_unlock_bh(&eb->lock);
196 }
197 oz_pd_put(pd);
198 return count;
199 }
200 /*------------------------------------------------------------------------------
201 * Context: process
202 */
oz_set_active_pd(u8 * addr)203 static int oz_set_active_pd(u8 *addr)
204 {
205 int rc = 0;
206 struct oz_pd *pd;
207 struct oz_pd *old_pd;
208 pd = oz_pd_find(addr);
209 if (pd) {
210 spin_lock_bh(&g_cdev.lock);
211 memcpy(g_cdev.active_addr, addr, ETH_ALEN);
212 old_pd = g_cdev.active_pd;
213 g_cdev.active_pd = pd;
214 spin_unlock_bh(&g_cdev.lock);
215 if (old_pd)
216 oz_pd_put(old_pd);
217 } else {
218 if (!memcmp(addr, "\0\0\0\0\0\0", sizeof(addr))) {
219 spin_lock_bh(&g_cdev.lock);
220 pd = g_cdev.active_pd;
221 g_cdev.active_pd = 0;
222 memset(g_cdev.active_addr, 0,
223 sizeof(g_cdev.active_addr));
224 spin_unlock_bh(&g_cdev.lock);
225 if (pd)
226 oz_pd_put(pd);
227 } else {
228 rc = -1;
229 }
230 }
231 return rc;
232 }
233 /*------------------------------------------------------------------------------
234 * Context: process
235 */
oz_cdev_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)236 long oz_cdev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
237 {
238 int rc = 0;
239 if (_IOC_TYPE(cmd) != OZ_IOCTL_MAGIC)
240 return -ENOTTY;
241 if (_IOC_NR(cmd) > OZ_IOCTL_MAX)
242 return -ENOTTY;
243 if (_IOC_DIR(cmd) & _IOC_READ)
244 rc = !access_ok(VERIFY_WRITE, (void __user *)arg,
245 _IOC_SIZE(cmd));
246 else if (_IOC_DIR(cmd) & _IOC_WRITE)
247 rc = !access_ok(VERIFY_READ, (void __user *)arg,
248 _IOC_SIZE(cmd));
249 if (rc)
250 return -EFAULT;
251 switch (cmd) {
252 case OZ_IOCTL_GET_PD_LIST: {
253 struct oz_pd_list list;
254 oz_trace("OZ_IOCTL_GET_PD_LIST\n");
255 list.count = oz_get_pd_list(list.addr, OZ_MAX_PDS);
256 if (copy_to_user((void __user *)arg, &list,
257 sizeof(list)))
258 return -EFAULT;
259 }
260 break;
261 case OZ_IOCTL_SET_ACTIVE_PD: {
262 u8 addr[ETH_ALEN];
263 oz_trace("OZ_IOCTL_SET_ACTIVE_PD\n");
264 if (copy_from_user(addr, (void __user *)arg, ETH_ALEN))
265 return -EFAULT;
266 rc = oz_set_active_pd(addr);
267 }
268 break;
269 case OZ_IOCTL_GET_ACTIVE_PD: {
270 u8 addr[ETH_ALEN];
271 oz_trace("OZ_IOCTL_GET_ACTIVE_PD\n");
272 spin_lock_bh(&g_cdev.lock);
273 memcpy(addr, g_cdev.active_addr, ETH_ALEN);
274 spin_unlock_bh(&g_cdev.lock);
275 if (copy_to_user((void __user *)arg, addr, ETH_ALEN))
276 return -EFAULT;
277 }
278 break;
279 #ifdef WANT_EVENT_TRACE
280 case OZ_IOCTL_CLEAR_EVENTS:
281 oz_events_clear();
282 break;
283 case OZ_IOCTL_GET_EVENTS:
284 rc = oz_events_copy((void __user *)arg);
285 break;
286 case OZ_IOCTL_SET_EVENT_MASK:
287 if (copy_from_user(&g_evt_mask, (void __user *)arg,
288 sizeof(unsigned long))) {
289 return -EFAULT;
290 }
291 break;
292 #endif /* WANT_EVENT_TRACE */
293 case OZ_IOCTL_ADD_BINDING:
294 case OZ_IOCTL_REMOVE_BINDING: {
295 struct oz_binding_info b;
296 if (copy_from_user(&b, (void __user *)arg,
297 sizeof(struct oz_binding_info))) {
298 return -EFAULT;
299 }
300 /* Make sure name is null terminated. */
301 b.name[OZ_MAX_BINDING_LEN-1] = 0;
302 if (cmd == OZ_IOCTL_ADD_BINDING)
303 oz_binding_add(b.name);
304 else
305 oz_binding_remove(b.name);
306 }
307 break;
308 }
309 return rc;
310 }
311 /*------------------------------------------------------------------------------
312 * Context: process
313 */
oz_cdev_poll(struct file * filp,poll_table * wait)314 unsigned int oz_cdev_poll(struct file *filp, poll_table *wait)
315 {
316 unsigned int ret = 0;
317 struct oz_cdev *dev = filp->private_data;
318 oz_trace("Poll called wait = %p\n", wait);
319 spin_lock_bh(&dev->lock);
320 if (dev->active_pd) {
321 struct oz_serial_ctx *ctx = oz_cdev_claim_ctx(dev->active_pd);
322 if (ctx) {
323 if (ctx->rd_in != ctx->rd_out)
324 ret |= POLLIN | POLLRDNORM;
325 oz_cdev_release_ctx(ctx);
326 }
327 }
328 spin_unlock_bh(&dev->lock);
329 if (wait)
330 poll_wait(filp, &dev->rdq, wait);
331 return ret;
332 }
333 /*------------------------------------------------------------------------------
334 */
335 const struct file_operations oz_fops = {
336 .owner = THIS_MODULE,
337 .open = oz_cdev_open,
338 .release = oz_cdev_release,
339 .read = oz_cdev_read,
340 .write = oz_cdev_write,
341 .unlocked_ioctl = oz_cdev_ioctl,
342 .poll = oz_cdev_poll
343 };
344 /*------------------------------------------------------------------------------
345 * Context: process
346 */
oz_cdev_register(void)347 int oz_cdev_register(void)
348 {
349 int err;
350 memset(&g_cdev, 0, sizeof(g_cdev));
351 err = alloc_chrdev_region(&g_cdev.devnum, 0, 1, "ozwpan");
352 if (err < 0)
353 return err;
354 oz_trace("Alloc dev number %d:%d\n", MAJOR(g_cdev.devnum),
355 MINOR(g_cdev.devnum));
356 cdev_init(&g_cdev.cdev, &oz_fops);
357 g_cdev.cdev.owner = THIS_MODULE;
358 g_cdev.cdev.ops = &oz_fops;
359 spin_lock_init(&g_cdev.lock);
360 init_waitqueue_head(&g_cdev.rdq);
361 err = cdev_add(&g_cdev.cdev, g_cdev.devnum, 1);
362 return 0;
363 }
364 /*------------------------------------------------------------------------------
365 * Context: process
366 */
oz_cdev_deregister(void)367 int oz_cdev_deregister(void)
368 {
369 cdev_del(&g_cdev.cdev);
370 unregister_chrdev_region(g_cdev.devnum, 1);
371 return 0;
372 }
373 /*------------------------------------------------------------------------------
374 * Context: process
375 */
oz_cdev_init(void)376 int oz_cdev_init(void)
377 {
378 oz_event_log(OZ_EVT_SERVICE, 1, OZ_APPID_SERIAL, 0, 0);
379 oz_app_enable(OZ_APPID_SERIAL, 1);
380 return 0;
381 }
382 /*------------------------------------------------------------------------------
383 * Context: process
384 */
oz_cdev_term(void)385 void oz_cdev_term(void)
386 {
387 oz_event_log(OZ_EVT_SERVICE, 2, OZ_APPID_SERIAL, 0, 0);
388 oz_app_enable(OZ_APPID_SERIAL, 0);
389 }
390 /*------------------------------------------------------------------------------
391 * Context: softirq-serialized
392 */
oz_cdev_start(struct oz_pd * pd,int resume)393 int oz_cdev_start(struct oz_pd *pd, int resume)
394 {
395 struct oz_serial_ctx *ctx;
396 struct oz_serial_ctx *old_ctx = 0;
397 oz_event_log(OZ_EVT_SERVICE, 3, OZ_APPID_SERIAL, 0, resume);
398 if (resume) {
399 oz_trace("Serial service resumed.\n");
400 return 0;
401 }
402 ctx = kzalloc(sizeof(struct oz_serial_ctx), GFP_ATOMIC);
403 if (ctx == 0)
404 return -ENOMEM;
405 atomic_set(&ctx->ref_count, 1);
406 ctx->tx_seq_num = 1;
407 spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
408 old_ctx = pd->app_ctx[OZ_APPID_SERIAL-1];
409 if (old_ctx) {
410 spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
411 kfree(ctx);
412 } else {
413 pd->app_ctx[OZ_APPID_SERIAL-1] = ctx;
414 spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
415 }
416 spin_lock(&g_cdev.lock);
417 if ((g_cdev.active_pd == 0) &&
418 (memcmp(pd->mac_addr, g_cdev.active_addr, ETH_ALEN) == 0)) {
419 oz_pd_get(pd);
420 g_cdev.active_pd = pd;
421 oz_trace("Active PD arrived.\n");
422 }
423 spin_unlock(&g_cdev.lock);
424 oz_trace("Serial service started.\n");
425 return 0;
426 }
427 /*------------------------------------------------------------------------------
428 * Context: softirq or process
429 */
oz_cdev_stop(struct oz_pd * pd,int pause)430 void oz_cdev_stop(struct oz_pd *pd, int pause)
431 {
432 struct oz_serial_ctx *ctx;
433 oz_event_log(OZ_EVT_SERVICE, 4, OZ_APPID_SERIAL, 0, pause);
434 if (pause) {
435 oz_trace("Serial service paused.\n");
436 return;
437 }
438 spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
439 ctx = (struct oz_serial_ctx *)pd->app_ctx[OZ_APPID_SERIAL-1];
440 pd->app_ctx[OZ_APPID_SERIAL-1] = 0;
441 spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]);
442 if (ctx)
443 oz_cdev_release_ctx(ctx);
444 spin_lock(&g_cdev.lock);
445 if (pd == g_cdev.active_pd)
446 g_cdev.active_pd = 0;
447 else
448 pd = 0;
449 spin_unlock(&g_cdev.lock);
450 if (pd) {
451 oz_pd_put(pd);
452 oz_trace("Active PD departed.\n");
453 }
454 oz_trace("Serial service stopped.\n");
455 }
456 /*------------------------------------------------------------------------------
457 * Context: softirq-serialized
458 */
oz_cdev_rx(struct oz_pd * pd,struct oz_elt * elt)459 void oz_cdev_rx(struct oz_pd *pd, struct oz_elt *elt)
460 {
461 struct oz_serial_ctx *ctx;
462 struct oz_app_hdr *app_hdr;
463 u8 *data;
464 int len;
465 int space;
466 int copy_sz;
467 int ix;
468
469 ctx = oz_cdev_claim_ctx(pd);
470 if (ctx == 0) {
471 oz_trace("Cannot claim serial context.\n");
472 return;
473 }
474
475 app_hdr = (struct oz_app_hdr *)(elt+1);
476 /* If sequence number is non-zero then check it is not a duplicate.
477 */
478 if (app_hdr->elt_seq_num != 0) {
479 if (((ctx->rx_seq_num - app_hdr->elt_seq_num) & 0x80) == 0) {
480 /* Reject duplicate element. */
481 oz_trace("Duplicate element:%02x %02x\n",
482 app_hdr->elt_seq_num, ctx->rx_seq_num);
483 goto out;
484 }
485 }
486 ctx->rx_seq_num = app_hdr->elt_seq_num;
487 len = elt->length - sizeof(struct oz_app_hdr);
488 data = ((u8 *)(elt+1)) + sizeof(struct oz_app_hdr);
489 if (len <= 0)
490 goto out;
491 space = ctx->rd_out - ctx->rd_in - 1;
492 if (space < 0)
493 space += OZ_RD_BUF_SZ;
494 if (len > space) {
495 oz_trace("Not enough space:%d %d\n", len, space);
496 len = space;
497 }
498 ix = ctx->rd_in;
499 copy_sz = OZ_RD_BUF_SZ - ix;
500 if (copy_sz > len)
501 copy_sz = len;
502 memcpy(&ctx->rd_buf[ix], data, copy_sz);
503 len -= copy_sz;
504 ix += copy_sz;
505 if (ix == OZ_RD_BUF_SZ)
506 ix = 0;
507 if (len) {
508 memcpy(ctx->rd_buf, data+copy_sz, len);
509 ix = len;
510 }
511 ctx->rd_in = ix;
512 wake_up(&g_cdev.rdq);
513 out:
514 oz_cdev_release_ctx(ctx);
515 }
516 /*------------------------------------------------------------------------------
517 * Context: softirq
518 */
oz_cdev_heartbeat(struct oz_pd * pd)519 void oz_cdev_heartbeat(struct oz_pd *pd)
520 {
521 }
522