1 /*
2 * f_phonet.c -- USB CDC Phonet function
3 *
4 * Copyright (C) 2007-2008 Nokia Corporation. All rights reserved.
5 *
6 * Author: Rémi Denis-Courmont
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * version 2 as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20 * 02110-1301 USA
21 */
22
23 #include <linux/kernel.h>
24 #include <linux/device.h>
25
26 #include <linux/netdevice.h>
27 #include <linux/if_ether.h>
28 #include <linux/if_phonet.h>
29 #include <linux/if_arp.h>
30
31 #include <linux/usb/ch9.h>
32 #include <linux/usb/cdc.h>
33 #include <linux/usb/composite.h>
34
35 #include "u_phonet.h"
36
37 #define PN_MEDIA_USB 0x1B
38
39 /*-------------------------------------------------------------------------*/
40
41 struct phonet_port {
42 struct f_phonet *usb;
43 spinlock_t lock;
44 };
45
46 struct f_phonet {
47 struct usb_function function;
48 struct net_device *dev;
49 struct usb_ep *in_ep, *out_ep;
50
51 struct usb_request *in_req;
52 struct usb_request *out_reqv[0];
53 };
54
55 static int phonet_rxq_size = 2;
56
func_to_pn(struct usb_function * f)57 static inline struct f_phonet *func_to_pn(struct usb_function *f)
58 {
59 return container_of(f, struct f_phonet, function);
60 }
61
62 /*-------------------------------------------------------------------------*/
63
64 #define USB_CDC_SUBCLASS_PHONET 0xfe
65 #define USB_CDC_PHONET_TYPE 0xab
66
67 static struct usb_interface_descriptor
68 pn_control_intf_desc = {
69 .bLength = sizeof pn_control_intf_desc,
70 .bDescriptorType = USB_DT_INTERFACE,
71
72 /* .bInterfaceNumber = DYNAMIC, */
73 .bInterfaceClass = USB_CLASS_COMM,
74 .bInterfaceSubClass = USB_CDC_SUBCLASS_PHONET,
75 };
76
77 static const struct usb_cdc_header_desc
78 pn_header_desc = {
79 .bLength = sizeof pn_header_desc,
80 .bDescriptorType = USB_DT_CS_INTERFACE,
81 .bDescriptorSubType = USB_CDC_HEADER_TYPE,
82 .bcdCDC = __constant_cpu_to_le16(0x0110),
83 };
84
85 static const struct usb_cdc_header_desc
86 pn_phonet_desc = {
87 .bLength = sizeof pn_phonet_desc,
88 .bDescriptorType = USB_DT_CS_INTERFACE,
89 .bDescriptorSubType = USB_CDC_PHONET_TYPE,
90 .bcdCDC = __constant_cpu_to_le16(0x1505), /* ??? */
91 };
92
93 static struct usb_cdc_union_desc
94 pn_union_desc = {
95 .bLength = sizeof pn_union_desc,
96 .bDescriptorType = USB_DT_CS_INTERFACE,
97 .bDescriptorSubType = USB_CDC_UNION_TYPE,
98
99 /* .bMasterInterface0 = DYNAMIC, */
100 /* .bSlaveInterface0 = DYNAMIC, */
101 };
102
103 static struct usb_interface_descriptor
104 pn_data_nop_intf_desc = {
105 .bLength = sizeof pn_data_nop_intf_desc,
106 .bDescriptorType = USB_DT_INTERFACE,
107
108 /* .bInterfaceNumber = DYNAMIC, */
109 .bAlternateSetting = 0,
110 .bNumEndpoints = 0,
111 .bInterfaceClass = USB_CLASS_CDC_DATA,
112 };
113
114 static struct usb_interface_descriptor
115 pn_data_intf_desc = {
116 .bLength = sizeof pn_data_intf_desc,
117 .bDescriptorType = USB_DT_INTERFACE,
118
119 /* .bInterfaceNumber = DYNAMIC, */
120 .bAlternateSetting = 1,
121 .bNumEndpoints = 2,
122 .bInterfaceClass = USB_CLASS_CDC_DATA,
123 };
124
125 static struct usb_endpoint_descriptor
126 pn_fs_sink_desc = {
127 .bLength = USB_DT_ENDPOINT_SIZE,
128 .bDescriptorType = USB_DT_ENDPOINT,
129
130 .bEndpointAddress = USB_DIR_OUT,
131 .bmAttributes = USB_ENDPOINT_XFER_BULK,
132 };
133
134 static struct usb_endpoint_descriptor
135 pn_hs_sink_desc = {
136 .bLength = USB_DT_ENDPOINT_SIZE,
137 .bDescriptorType = USB_DT_ENDPOINT,
138
139 .bEndpointAddress = USB_DIR_OUT,
140 .bmAttributes = USB_ENDPOINT_XFER_BULK,
141 .wMaxPacketSize = __constant_cpu_to_le16(512),
142 };
143
144 static struct usb_endpoint_descriptor
145 pn_fs_source_desc = {
146 .bLength = USB_DT_ENDPOINT_SIZE,
147 .bDescriptorType = USB_DT_ENDPOINT,
148
149 .bEndpointAddress = USB_DIR_IN,
150 .bmAttributes = USB_ENDPOINT_XFER_BULK,
151 };
152
153 static struct usb_endpoint_descriptor
154 pn_hs_source_desc = {
155 .bLength = USB_DT_ENDPOINT_SIZE,
156 .bDescriptorType = USB_DT_ENDPOINT,
157
158 .bEndpointAddress = USB_DIR_IN,
159 .bmAttributes = USB_ENDPOINT_XFER_BULK,
160 .wMaxPacketSize = __constant_cpu_to_le16(512),
161 };
162
163 static struct usb_descriptor_header *fs_pn_function[] = {
164 (struct usb_descriptor_header *) &pn_control_intf_desc,
165 (struct usb_descriptor_header *) &pn_header_desc,
166 (struct usb_descriptor_header *) &pn_phonet_desc,
167 (struct usb_descriptor_header *) &pn_union_desc,
168 (struct usb_descriptor_header *) &pn_data_nop_intf_desc,
169 (struct usb_descriptor_header *) &pn_data_intf_desc,
170 (struct usb_descriptor_header *) &pn_fs_sink_desc,
171 (struct usb_descriptor_header *) &pn_fs_source_desc,
172 NULL,
173 };
174
175 static struct usb_descriptor_header *hs_pn_function[] = {
176 (struct usb_descriptor_header *) &pn_control_intf_desc,
177 (struct usb_descriptor_header *) &pn_header_desc,
178 (struct usb_descriptor_header *) &pn_phonet_desc,
179 (struct usb_descriptor_header *) &pn_union_desc,
180 (struct usb_descriptor_header *) &pn_data_nop_intf_desc,
181 (struct usb_descriptor_header *) &pn_data_intf_desc,
182 (struct usb_descriptor_header *) &pn_hs_sink_desc,
183 (struct usb_descriptor_header *) &pn_hs_source_desc,
184 NULL,
185 };
186
187 /*-------------------------------------------------------------------------*/
188
pn_net_open(struct net_device * dev)189 static int pn_net_open(struct net_device *dev)
190 {
191 if (netif_carrier_ok(dev))
192 netif_wake_queue(dev);
193 return 0;
194 }
195
pn_net_close(struct net_device * dev)196 static int pn_net_close(struct net_device *dev)
197 {
198 netif_stop_queue(dev);
199 return 0;
200 }
201
pn_tx_complete(struct usb_ep * ep,struct usb_request * req)202 static void pn_tx_complete(struct usb_ep *ep, struct usb_request *req)
203 {
204 struct f_phonet *fp = ep->driver_data;
205 struct net_device *dev = fp->dev;
206 struct sk_buff *skb = req->context;
207
208 switch (req->status) {
209 case 0:
210 dev->stats.tx_packets++;
211 dev->stats.tx_bytes += skb->len;
212 break;
213
214 case -ESHUTDOWN: /* disconnected */
215 case -ECONNRESET: /* disabled */
216 dev->stats.tx_aborted_errors++;
217 default:
218 dev->stats.tx_errors++;
219 }
220
221 dev_kfree_skb_any(skb);
222 if (netif_carrier_ok(dev))
223 netif_wake_queue(dev);
224 }
225
pn_net_xmit(struct sk_buff * skb,struct net_device * dev)226 static int pn_net_xmit(struct sk_buff *skb, struct net_device *dev)
227 {
228 struct phonet_port *port = netdev_priv(dev);
229 struct f_phonet *fp;
230 struct usb_request *req;
231 unsigned long flags;
232
233 if (skb->protocol != htons(ETH_P_PHONET))
234 goto out;
235
236 spin_lock_irqsave(&port->lock, flags);
237 fp = port->usb;
238 if (unlikely(!fp)) /* race with carrier loss */
239 goto out_unlock;
240
241 req = fp->in_req;
242 req->buf = skb->data;
243 req->length = skb->len;
244 req->complete = pn_tx_complete;
245 req->zero = 1;
246 req->context = skb;
247
248 if (unlikely(usb_ep_queue(fp->in_ep, req, GFP_ATOMIC)))
249 goto out_unlock;
250
251 netif_stop_queue(dev);
252 skb = NULL;
253
254 out_unlock:
255 spin_unlock_irqrestore(&port->lock, flags);
256 out:
257 if (unlikely(skb)) {
258 dev_kfree_skb_any(skb);
259 dev->stats.tx_dropped++;
260 }
261 return 0;
262 }
263
pn_net_mtu(struct net_device * dev,int new_mtu)264 static int pn_net_mtu(struct net_device *dev, int new_mtu)
265 {
266 struct phonet_port *port = netdev_priv(dev);
267 unsigned long flags;
268 int err = -EBUSY;
269
270 if ((new_mtu < PHONET_MIN_MTU) || (new_mtu > PHONET_MAX_MTU))
271 return -EINVAL;
272
273 spin_lock_irqsave(&port->lock, flags);
274 if (!netif_carrier_ok(dev)) {
275 dev->mtu = new_mtu;
276 err = 0;
277 }
278 spin_unlock_irqrestore(&port->lock, flags);
279 return err;
280 }
281
282 static const struct net_device_ops pn_netdev_ops = {
283 .ndo_open = pn_net_open,
284 .ndo_stop = pn_net_close,
285 .ndo_start_xmit = pn_net_xmit,
286 .ndo_change_mtu = pn_net_mtu,
287 };
288
pn_net_setup(struct net_device * dev)289 static void pn_net_setup(struct net_device *dev)
290 {
291 dev->features = 0;
292 dev->type = ARPHRD_PHONET;
293 dev->flags = IFF_POINTOPOINT | IFF_NOARP;
294 dev->mtu = PHONET_DEV_MTU;
295 dev->hard_header_len = 1;
296 dev->dev_addr[0] = PN_MEDIA_USB;
297 dev->addr_len = 1;
298 dev->tx_queue_len = 1;
299
300 dev->netdev_ops = &pn_netdev_ops;
301 dev->destructor = free_netdev;
302 dev->header_ops = &phonet_header_ops;
303 }
304
305 /*-------------------------------------------------------------------------*/
306
307 /*
308 * Queue buffer for data from the host
309 */
310 static int
pn_rx_submit(struct f_phonet * fp,struct usb_request * req,gfp_t gfp_flags)311 pn_rx_submit(struct f_phonet *fp, struct usb_request *req, gfp_t gfp_flags)
312 {
313 struct sk_buff *skb;
314 const size_t size = fp->dev->mtu;
315 int err;
316
317 skb = alloc_skb(size, gfp_flags);
318 if (!skb)
319 return -ENOMEM;
320
321 req->buf = skb->data;
322 req->length = size;
323 req->context = skb;
324
325 err = usb_ep_queue(fp->out_ep, req, gfp_flags);
326 if (unlikely(err))
327 dev_kfree_skb_any(skb);
328 return err;
329 }
330
pn_rx_complete(struct usb_ep * ep,struct usb_request * req)331 static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req)
332 {
333 struct f_phonet *fp = ep->driver_data;
334 struct net_device *dev = fp->dev;
335 struct sk_buff *skb = req->context;
336 int status = req->status;
337
338 switch (status) {
339 case 0:
340 if (unlikely(!netif_running(dev)))
341 break;
342 if (unlikely(req->actual < 1))
343 break;
344 skb_put(skb, req->actual);
345 skb->protocol = htons(ETH_P_PHONET);
346 skb_reset_mac_header(skb);
347 __skb_pull(skb, 1);
348 skb->dev = dev;
349 dev->stats.rx_packets++;
350 dev->stats.rx_bytes += skb->len;
351
352 netif_rx(skb);
353 skb = NULL;
354 break;
355
356 /* Do not resubmit in these cases: */
357 case -ESHUTDOWN: /* disconnect */
358 case -ECONNABORTED: /* hw reset */
359 case -ECONNRESET: /* dequeued (unlink or netif down) */
360 req = NULL;
361 break;
362
363 /* Do resubmit in these cases: */
364 case -EOVERFLOW: /* request buffer overflow */
365 dev->stats.rx_over_errors++;
366 default:
367 dev->stats.rx_errors++;
368 break;
369 }
370
371 if (skb)
372 dev_kfree_skb_any(skb);
373 if (req)
374 pn_rx_submit(fp, req, GFP_ATOMIC);
375 }
376
377 /*-------------------------------------------------------------------------*/
378
__pn_reset(struct usb_function * f)379 static void __pn_reset(struct usb_function *f)
380 {
381 struct f_phonet *fp = func_to_pn(f);
382 struct net_device *dev = fp->dev;
383 struct phonet_port *port = netdev_priv(dev);
384
385 netif_carrier_off(dev);
386 netif_stop_queue(dev);
387 port->usb = NULL;
388
389 usb_ep_disable(fp->out_ep);
390 usb_ep_disable(fp->in_ep);
391 }
392
pn_set_alt(struct usb_function * f,unsigned intf,unsigned alt)393 static int pn_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
394 {
395 struct f_phonet *fp = func_to_pn(f);
396 struct usb_gadget *gadget = fp->function.config->cdev->gadget;
397
398 if (intf == pn_control_intf_desc.bInterfaceNumber)
399 /* control interface, no altsetting */
400 return (alt > 0) ? -EINVAL : 0;
401
402 if (intf == pn_data_intf_desc.bInterfaceNumber) {
403 struct net_device *dev = fp->dev;
404 struct phonet_port *port = netdev_priv(dev);
405
406 /* data intf (0: inactive, 1: active) */
407 if (alt > 1)
408 return -EINVAL;
409
410 spin_lock(&port->lock);
411 __pn_reset(f);
412 if (alt == 1) {
413 struct usb_endpoint_descriptor *out, *in;
414 int i;
415
416 out = ep_choose(gadget,
417 &pn_hs_sink_desc,
418 &pn_fs_sink_desc);
419 in = ep_choose(gadget,
420 &pn_hs_source_desc,
421 &pn_fs_source_desc);
422 usb_ep_enable(fp->out_ep, out);
423 usb_ep_enable(fp->in_ep, in);
424
425 port->usb = fp;
426 fp->out_ep->driver_data = fp;
427 fp->in_ep->driver_data = fp;
428
429 netif_carrier_on(dev);
430 if (netif_running(dev))
431 netif_wake_queue(dev);
432 for (i = 0; i < phonet_rxq_size; i++)
433 pn_rx_submit(fp, fp->out_reqv[i], GFP_ATOMIC);
434 }
435 spin_unlock(&port->lock);
436 return 0;
437 }
438
439 return -EINVAL;
440 }
441
pn_get_alt(struct usb_function * f,unsigned intf)442 static int pn_get_alt(struct usb_function *f, unsigned intf)
443 {
444 struct f_phonet *fp = func_to_pn(f);
445
446 if (intf == pn_control_intf_desc.bInterfaceNumber)
447 return 0;
448
449 if (intf == pn_data_intf_desc.bInterfaceNumber) {
450 struct phonet_port *port = netdev_priv(fp->dev);
451 u8 alt;
452
453 spin_lock(&port->lock);
454 alt = port->usb != NULL;
455 spin_unlock(&port->lock);
456 return alt;
457 }
458
459 return -EINVAL;
460 }
461
pn_disconnect(struct usb_function * f)462 static void pn_disconnect(struct usb_function *f)
463 {
464 struct f_phonet *fp = func_to_pn(f);
465 struct phonet_port *port = netdev_priv(fp->dev);
466 unsigned long flags;
467
468 /* remain disabled until set_alt */
469 spin_lock_irqsave(&port->lock, flags);
470 __pn_reset(f);
471 spin_unlock_irqrestore(&port->lock, flags);
472 }
473
474 /*-------------------------------------------------------------------------*/
475
476 static __init
pn_bind(struct usb_configuration * c,struct usb_function * f)477 int pn_bind(struct usb_configuration *c, struct usb_function *f)
478 {
479 struct usb_composite_dev *cdev = c->cdev;
480 struct usb_gadget *gadget = cdev->gadget;
481 struct f_phonet *fp = func_to_pn(f);
482 struct usb_ep *ep;
483 int status, i;
484
485 /* Reserve interface IDs */
486 status = usb_interface_id(c, f);
487 if (status < 0)
488 goto err;
489 pn_control_intf_desc.bInterfaceNumber = status;
490 pn_union_desc.bMasterInterface0 = status;
491
492 status = usb_interface_id(c, f);
493 if (status < 0)
494 goto err;
495 pn_data_nop_intf_desc.bInterfaceNumber = status;
496 pn_data_intf_desc.bInterfaceNumber = status;
497 pn_union_desc.bSlaveInterface0 = status;
498
499 /* Reserve endpoints */
500 status = -ENODEV;
501 ep = usb_ep_autoconfig(gadget, &pn_fs_sink_desc);
502 if (!ep)
503 goto err;
504 fp->out_ep = ep;
505 ep->driver_data = fp; /* Claim */
506
507 ep = usb_ep_autoconfig(gadget, &pn_fs_source_desc);
508 if (!ep)
509 goto err;
510 fp->in_ep = ep;
511 ep->driver_data = fp; /* Claim */
512
513 pn_hs_sink_desc.bEndpointAddress =
514 pn_fs_sink_desc.bEndpointAddress;
515 pn_hs_source_desc.bEndpointAddress =
516 pn_fs_source_desc.bEndpointAddress;
517
518 /* Do not try to bind Phonet twice... */
519 fp->function.descriptors = fs_pn_function;
520 fp->function.hs_descriptors = hs_pn_function;
521
522 /* Incoming USB requests */
523 status = -ENOMEM;
524 for (i = 0; i < phonet_rxq_size; i++) {
525 struct usb_request *req;
526
527 req = usb_ep_alloc_request(fp->out_ep, GFP_KERNEL);
528 if (!req)
529 goto err;
530
531 req->complete = pn_rx_complete;
532 fp->out_reqv[i] = req;
533 }
534
535 /* Outgoing USB requests */
536 fp->in_req = usb_ep_alloc_request(fp->in_ep, GFP_KERNEL);
537 if (!fp->in_req)
538 goto err;
539
540 INFO(cdev, "USB CDC Phonet function\n");
541 INFO(cdev, "using %s, OUT %s, IN %s\n", cdev->gadget->name,
542 fp->out_ep->name, fp->in_ep->name);
543 return 0;
544
545 err:
546 if (fp->out_ep)
547 fp->out_ep->driver_data = NULL;
548 if (fp->in_ep)
549 fp->in_ep->driver_data = NULL;
550 ERROR(cdev, "USB CDC Phonet: cannot autoconfigure\n");
551 return status;
552 }
553
554 static void
pn_unbind(struct usb_configuration * c,struct usb_function * f)555 pn_unbind(struct usb_configuration *c, struct usb_function *f)
556 {
557 struct f_phonet *fp = func_to_pn(f);
558 int i;
559
560 /* We are already disconnected */
561 if (fp->in_req)
562 usb_ep_free_request(fp->in_ep, fp->in_req);
563 for (i = 0; i < phonet_rxq_size; i++)
564 if (fp->out_reqv[i])
565 usb_ep_free_request(fp->out_ep, fp->out_reqv[i]);
566
567 kfree(fp);
568 }
569
570 /*-------------------------------------------------------------------------*/
571
572 static struct net_device *dev;
573
phonet_bind_config(struct usb_configuration * c)574 int __init phonet_bind_config(struct usb_configuration *c)
575 {
576 struct f_phonet *fp;
577 int err;
578
579 fp = kzalloc(sizeof(*fp), GFP_KERNEL);
580 if (!fp)
581 return -ENOMEM;
582
583 fp->dev = dev;
584 fp->function.name = "phonet";
585 fp->function.bind = pn_bind;
586 fp->function.unbind = pn_unbind;
587 fp->function.set_alt = pn_set_alt;
588 fp->function.get_alt = pn_get_alt;
589 fp->function.disable = pn_disconnect;
590
591 err = usb_add_function(c, &fp->function);
592 if (err)
593 kfree(fp);
594 return err;
595 }
596
gphonet_setup(struct usb_gadget * gadget)597 int __init gphonet_setup(struct usb_gadget *gadget)
598 {
599 struct phonet_port *port;
600 int err;
601
602 /* Create net device */
603 BUG_ON(dev);
604 dev = alloc_netdev(sizeof(*port)
605 + (phonet_rxq_size * sizeof(struct usb_request *)),
606 "upnlink%d", pn_net_setup);
607 if (!dev)
608 return -ENOMEM;
609
610 port = netdev_priv(dev);
611 spin_lock_init(&port->lock);
612 netif_carrier_off(dev);
613 netif_stop_queue(dev);
614 SET_NETDEV_DEV(dev, &gadget->dev);
615
616 err = register_netdev(dev);
617 if (err)
618 free_netdev(dev);
619 return err;
620 }
621
gphonet_cleanup(void)622 void gphonet_cleanup(void)
623 {
624 unregister_netdev(dev);
625 }
626