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/slab.h>
24 #include <linux/kernel.h>
25 #include <linux/device.h>
26
27 #include <linux/netdevice.h>
28 #include <linux/if_ether.h>
29 #include <linux/if_phonet.h>
30 #include <linux/if_arp.h>
31
32 #include <linux/usb/ch9.h>
33 #include <linux/usb/cdc.h>
34 #include <linux/usb/composite.h>
35
36 #include "u_phonet.h"
37
38 #define PN_MEDIA_USB 0x1B
39 #define MAXPACKET 512
40 #if (PAGE_SIZE % MAXPACKET)
41 #error MAXPACKET must divide PAGE_SIZE!
42 #endif
43
44 /*-------------------------------------------------------------------------*/
45
46 struct phonet_port {
47 struct f_phonet *usb;
48 spinlock_t lock;
49 };
50
51 struct f_phonet {
52 struct usb_function function;
53 struct {
54 struct sk_buff *skb;
55 spinlock_t lock;
56 } rx;
57 struct net_device *dev;
58 struct usb_ep *in_ep, *out_ep;
59
60 struct usb_request *in_req;
61 struct usb_request *out_reqv[0];
62 };
63
64 static int phonet_rxq_size = 17;
65
func_to_pn(struct usb_function * f)66 static inline struct f_phonet *func_to_pn(struct usb_function *f)
67 {
68 return container_of(f, struct f_phonet, function);
69 }
70
71 /*-------------------------------------------------------------------------*/
72
73 #define USB_CDC_SUBCLASS_PHONET 0xfe
74 #define USB_CDC_PHONET_TYPE 0xab
75
76 static struct usb_interface_descriptor
77 pn_control_intf_desc = {
78 .bLength = sizeof pn_control_intf_desc,
79 .bDescriptorType = USB_DT_INTERFACE,
80
81 /* .bInterfaceNumber = DYNAMIC, */
82 .bInterfaceClass = USB_CLASS_COMM,
83 .bInterfaceSubClass = USB_CDC_SUBCLASS_PHONET,
84 };
85
86 static const struct usb_cdc_header_desc
87 pn_header_desc = {
88 .bLength = sizeof pn_header_desc,
89 .bDescriptorType = USB_DT_CS_INTERFACE,
90 .bDescriptorSubType = USB_CDC_HEADER_TYPE,
91 .bcdCDC = cpu_to_le16(0x0110),
92 };
93
94 static const struct usb_cdc_header_desc
95 pn_phonet_desc = {
96 .bLength = sizeof pn_phonet_desc,
97 .bDescriptorType = USB_DT_CS_INTERFACE,
98 .bDescriptorSubType = USB_CDC_PHONET_TYPE,
99 .bcdCDC = cpu_to_le16(0x1505), /* ??? */
100 };
101
102 static struct usb_cdc_union_desc
103 pn_union_desc = {
104 .bLength = sizeof pn_union_desc,
105 .bDescriptorType = USB_DT_CS_INTERFACE,
106 .bDescriptorSubType = USB_CDC_UNION_TYPE,
107
108 /* .bMasterInterface0 = DYNAMIC, */
109 /* .bSlaveInterface0 = DYNAMIC, */
110 };
111
112 static struct usb_interface_descriptor
113 pn_data_nop_intf_desc = {
114 .bLength = sizeof pn_data_nop_intf_desc,
115 .bDescriptorType = USB_DT_INTERFACE,
116
117 /* .bInterfaceNumber = DYNAMIC, */
118 .bAlternateSetting = 0,
119 .bNumEndpoints = 0,
120 .bInterfaceClass = USB_CLASS_CDC_DATA,
121 };
122
123 static struct usb_interface_descriptor
124 pn_data_intf_desc = {
125 .bLength = sizeof pn_data_intf_desc,
126 .bDescriptorType = USB_DT_INTERFACE,
127
128 /* .bInterfaceNumber = DYNAMIC, */
129 .bAlternateSetting = 1,
130 .bNumEndpoints = 2,
131 .bInterfaceClass = USB_CLASS_CDC_DATA,
132 };
133
134 static struct usb_endpoint_descriptor
135 pn_fs_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 };
142
143 static struct usb_endpoint_descriptor
144 pn_hs_sink_desc = {
145 .bLength = USB_DT_ENDPOINT_SIZE,
146 .bDescriptorType = USB_DT_ENDPOINT,
147
148 .bEndpointAddress = USB_DIR_OUT,
149 .bmAttributes = USB_ENDPOINT_XFER_BULK,
150 .wMaxPacketSize = cpu_to_le16(MAXPACKET),
151 };
152
153 static struct usb_endpoint_descriptor
154 pn_fs_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 };
161
162 static struct usb_endpoint_descriptor
163 pn_hs_source_desc = {
164 .bLength = USB_DT_ENDPOINT_SIZE,
165 .bDescriptorType = USB_DT_ENDPOINT,
166
167 .bEndpointAddress = USB_DIR_IN,
168 .bmAttributes = USB_ENDPOINT_XFER_BULK,
169 .wMaxPacketSize = cpu_to_le16(512),
170 };
171
172 static struct usb_descriptor_header *fs_pn_function[] = {
173 (struct usb_descriptor_header *) &pn_control_intf_desc,
174 (struct usb_descriptor_header *) &pn_header_desc,
175 (struct usb_descriptor_header *) &pn_phonet_desc,
176 (struct usb_descriptor_header *) &pn_union_desc,
177 (struct usb_descriptor_header *) &pn_data_nop_intf_desc,
178 (struct usb_descriptor_header *) &pn_data_intf_desc,
179 (struct usb_descriptor_header *) &pn_fs_sink_desc,
180 (struct usb_descriptor_header *) &pn_fs_source_desc,
181 NULL,
182 };
183
184 static struct usb_descriptor_header *hs_pn_function[] = {
185 (struct usb_descriptor_header *) &pn_control_intf_desc,
186 (struct usb_descriptor_header *) &pn_header_desc,
187 (struct usb_descriptor_header *) &pn_phonet_desc,
188 (struct usb_descriptor_header *) &pn_union_desc,
189 (struct usb_descriptor_header *) &pn_data_nop_intf_desc,
190 (struct usb_descriptor_header *) &pn_data_intf_desc,
191 (struct usb_descriptor_header *) &pn_hs_sink_desc,
192 (struct usb_descriptor_header *) &pn_hs_source_desc,
193 NULL,
194 };
195
196 /*-------------------------------------------------------------------------*/
197
pn_net_open(struct net_device * dev)198 static int pn_net_open(struct net_device *dev)
199 {
200 netif_wake_queue(dev);
201 return 0;
202 }
203
pn_net_close(struct net_device * dev)204 static int pn_net_close(struct net_device *dev)
205 {
206 netif_stop_queue(dev);
207 return 0;
208 }
209
pn_tx_complete(struct usb_ep * ep,struct usb_request * req)210 static void pn_tx_complete(struct usb_ep *ep, struct usb_request *req)
211 {
212 struct f_phonet *fp = ep->driver_data;
213 struct net_device *dev = fp->dev;
214 struct sk_buff *skb = req->context;
215
216 switch (req->status) {
217 case 0:
218 dev->stats.tx_packets++;
219 dev->stats.tx_bytes += skb->len;
220 break;
221
222 case -ESHUTDOWN: /* disconnected */
223 case -ECONNRESET: /* disabled */
224 dev->stats.tx_aborted_errors++;
225 default:
226 dev->stats.tx_errors++;
227 }
228
229 dev_kfree_skb_any(skb);
230 netif_wake_queue(dev);
231 }
232
pn_net_xmit(struct sk_buff * skb,struct net_device * dev)233 static int pn_net_xmit(struct sk_buff *skb, struct net_device *dev)
234 {
235 struct phonet_port *port = netdev_priv(dev);
236 struct f_phonet *fp;
237 struct usb_request *req;
238 unsigned long flags;
239
240 if (skb->protocol != htons(ETH_P_PHONET))
241 goto out;
242
243 spin_lock_irqsave(&port->lock, flags);
244 fp = port->usb;
245 if (unlikely(!fp)) /* race with carrier loss */
246 goto out_unlock;
247
248 req = fp->in_req;
249 req->buf = skb->data;
250 req->length = skb->len;
251 req->complete = pn_tx_complete;
252 req->zero = 1;
253 req->context = skb;
254
255 if (unlikely(usb_ep_queue(fp->in_ep, req, GFP_ATOMIC)))
256 goto out_unlock;
257
258 netif_stop_queue(dev);
259 skb = NULL;
260
261 out_unlock:
262 spin_unlock_irqrestore(&port->lock, flags);
263 out:
264 if (unlikely(skb)) {
265 dev_kfree_skb(skb);
266 dev->stats.tx_dropped++;
267 }
268 return NETDEV_TX_OK;
269 }
270
pn_net_mtu(struct net_device * dev,int new_mtu)271 static int pn_net_mtu(struct net_device *dev, int new_mtu)
272 {
273 if ((new_mtu < PHONET_MIN_MTU) || (new_mtu > PHONET_MAX_MTU))
274 return -EINVAL;
275 dev->mtu = new_mtu;
276 return 0;
277 }
278
279 static const struct net_device_ops pn_netdev_ops = {
280 .ndo_open = pn_net_open,
281 .ndo_stop = pn_net_close,
282 .ndo_start_xmit = pn_net_xmit,
283 .ndo_change_mtu = pn_net_mtu,
284 };
285
pn_net_setup(struct net_device * dev)286 static void pn_net_setup(struct net_device *dev)
287 {
288 dev->features = 0;
289 dev->type = ARPHRD_PHONET;
290 dev->flags = IFF_POINTOPOINT | IFF_NOARP;
291 dev->mtu = PHONET_DEV_MTU;
292 dev->hard_header_len = 1;
293 dev->dev_addr[0] = PN_MEDIA_USB;
294 dev->addr_len = 1;
295 dev->tx_queue_len = 1;
296
297 dev->netdev_ops = &pn_netdev_ops;
298 dev->destructor = free_netdev;
299 dev->header_ops = &phonet_header_ops;
300 }
301
302 /*-------------------------------------------------------------------------*/
303
304 /*
305 * Queue buffer for data from the host
306 */
307 static int
pn_rx_submit(struct f_phonet * fp,struct usb_request * req,gfp_t gfp_flags)308 pn_rx_submit(struct f_phonet *fp, struct usb_request *req, gfp_t gfp_flags)
309 {
310 struct net_device *dev = fp->dev;
311 struct page *page;
312 int err;
313
314 page = __netdev_alloc_page(dev, gfp_flags);
315 if (!page)
316 return -ENOMEM;
317
318 req->buf = page_address(page);
319 req->length = PAGE_SIZE;
320 req->context = page;
321
322 err = usb_ep_queue(fp->out_ep, req, gfp_flags);
323 if (unlikely(err))
324 netdev_free_page(dev, page);
325 return err;
326 }
327
pn_rx_complete(struct usb_ep * ep,struct usb_request * req)328 static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req)
329 {
330 struct f_phonet *fp = ep->driver_data;
331 struct net_device *dev = fp->dev;
332 struct page *page = req->context;
333 struct sk_buff *skb;
334 unsigned long flags;
335 int status = req->status;
336
337 switch (status) {
338 case 0:
339 spin_lock_irqsave(&fp->rx.lock, flags);
340 skb = fp->rx.skb;
341 if (!skb)
342 skb = fp->rx.skb = netdev_alloc_skb(dev, 12);
343 if (req->actual < req->length) /* Last fragment */
344 fp->rx.skb = NULL;
345 spin_unlock_irqrestore(&fp->rx.lock, flags);
346
347 if (unlikely(!skb))
348 break;
349
350 if (skb->len == 0) { /* First fragment */
351 skb->protocol = htons(ETH_P_PHONET);
352 skb_reset_mac_header(skb);
353 /* Can't use pskb_pull() on page in IRQ */
354 memcpy(skb_put(skb, 1), page_address(page), 1);
355 }
356
357 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page,
358 skb->len == 0, req->actual);
359 page = NULL;
360
361 if (req->actual < req->length) { /* Last fragment */
362 skb->dev = dev;
363 dev->stats.rx_packets++;
364 dev->stats.rx_bytes += skb->len;
365
366 netif_rx(skb);
367 }
368 break;
369
370 /* Do not resubmit in these cases: */
371 case -ESHUTDOWN: /* disconnect */
372 case -ECONNABORTED: /* hw reset */
373 case -ECONNRESET: /* dequeued (unlink or netif down) */
374 req = NULL;
375 break;
376
377 /* Do resubmit in these cases: */
378 case -EOVERFLOW: /* request buffer overflow */
379 dev->stats.rx_over_errors++;
380 default:
381 dev->stats.rx_errors++;
382 break;
383 }
384
385 if (page)
386 netdev_free_page(dev, page);
387 if (req)
388 pn_rx_submit(fp, req, GFP_ATOMIC);
389 }
390
391 /*-------------------------------------------------------------------------*/
392
__pn_reset(struct usb_function * f)393 static void __pn_reset(struct usb_function *f)
394 {
395 struct f_phonet *fp = func_to_pn(f);
396 struct net_device *dev = fp->dev;
397 struct phonet_port *port = netdev_priv(dev);
398
399 netif_carrier_off(dev);
400 port->usb = NULL;
401
402 usb_ep_disable(fp->out_ep);
403 usb_ep_disable(fp->in_ep);
404 if (fp->rx.skb) {
405 dev_kfree_skb_irq(fp->rx.skb);
406 fp->rx.skb = NULL;
407 }
408 }
409
pn_set_alt(struct usb_function * f,unsigned intf,unsigned alt)410 static int pn_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
411 {
412 struct f_phonet *fp = func_to_pn(f);
413 struct usb_gadget *gadget = fp->function.config->cdev->gadget;
414
415 if (intf == pn_control_intf_desc.bInterfaceNumber)
416 /* control interface, no altsetting */
417 return (alt > 0) ? -EINVAL : 0;
418
419 if (intf == pn_data_intf_desc.bInterfaceNumber) {
420 struct net_device *dev = fp->dev;
421 struct phonet_port *port = netdev_priv(dev);
422
423 /* data intf (0: inactive, 1: active) */
424 if (alt > 1)
425 return -EINVAL;
426
427 spin_lock(&port->lock);
428 __pn_reset(f);
429 if (alt == 1) {
430 struct usb_endpoint_descriptor *out, *in;
431 int i;
432
433 out = ep_choose(gadget,
434 &pn_hs_sink_desc,
435 &pn_fs_sink_desc);
436 in = ep_choose(gadget,
437 &pn_hs_source_desc,
438 &pn_fs_source_desc);
439 usb_ep_enable(fp->out_ep, out);
440 usb_ep_enable(fp->in_ep, in);
441
442 port->usb = fp;
443 fp->out_ep->driver_data = fp;
444 fp->in_ep->driver_data = fp;
445
446 netif_carrier_on(dev);
447 for (i = 0; i < phonet_rxq_size; i++)
448 pn_rx_submit(fp, fp->out_reqv[i], GFP_ATOMIC);
449 }
450 spin_unlock(&port->lock);
451 return 0;
452 }
453
454 return -EINVAL;
455 }
456
pn_get_alt(struct usb_function * f,unsigned intf)457 static int pn_get_alt(struct usb_function *f, unsigned intf)
458 {
459 struct f_phonet *fp = func_to_pn(f);
460
461 if (intf == pn_control_intf_desc.bInterfaceNumber)
462 return 0;
463
464 if (intf == pn_data_intf_desc.bInterfaceNumber) {
465 struct phonet_port *port = netdev_priv(fp->dev);
466 u8 alt;
467
468 spin_lock(&port->lock);
469 alt = port->usb != NULL;
470 spin_unlock(&port->lock);
471 return alt;
472 }
473
474 return -EINVAL;
475 }
476
pn_disconnect(struct usb_function * f)477 static void pn_disconnect(struct usb_function *f)
478 {
479 struct f_phonet *fp = func_to_pn(f);
480 struct phonet_port *port = netdev_priv(fp->dev);
481 unsigned long flags;
482
483 /* remain disabled until set_alt */
484 spin_lock_irqsave(&port->lock, flags);
485 __pn_reset(f);
486 spin_unlock_irqrestore(&port->lock, flags);
487 }
488
489 /*-------------------------------------------------------------------------*/
490
491 static __init
pn_bind(struct usb_configuration * c,struct usb_function * f)492 int pn_bind(struct usb_configuration *c, struct usb_function *f)
493 {
494 struct usb_composite_dev *cdev = c->cdev;
495 struct usb_gadget *gadget = cdev->gadget;
496 struct f_phonet *fp = func_to_pn(f);
497 struct usb_ep *ep;
498 int status, i;
499
500 /* Reserve interface IDs */
501 status = usb_interface_id(c, f);
502 if (status < 0)
503 goto err;
504 pn_control_intf_desc.bInterfaceNumber = status;
505 pn_union_desc.bMasterInterface0 = status;
506
507 status = usb_interface_id(c, f);
508 if (status < 0)
509 goto err;
510 pn_data_nop_intf_desc.bInterfaceNumber = status;
511 pn_data_intf_desc.bInterfaceNumber = status;
512 pn_union_desc.bSlaveInterface0 = status;
513
514 /* Reserve endpoints */
515 status = -ENODEV;
516 ep = usb_ep_autoconfig(gadget, &pn_fs_sink_desc);
517 if (!ep)
518 goto err;
519 fp->out_ep = ep;
520 ep->driver_data = fp; /* Claim */
521
522 ep = usb_ep_autoconfig(gadget, &pn_fs_source_desc);
523 if (!ep)
524 goto err;
525 fp->in_ep = ep;
526 ep->driver_data = fp; /* Claim */
527
528 pn_hs_sink_desc.bEndpointAddress =
529 pn_fs_sink_desc.bEndpointAddress;
530 pn_hs_source_desc.bEndpointAddress =
531 pn_fs_source_desc.bEndpointAddress;
532
533 /* Do not try to bind Phonet twice... */
534 fp->function.descriptors = fs_pn_function;
535 fp->function.hs_descriptors = hs_pn_function;
536
537 /* Incoming USB requests */
538 status = -ENOMEM;
539 for (i = 0; i < phonet_rxq_size; i++) {
540 struct usb_request *req;
541
542 req = usb_ep_alloc_request(fp->out_ep, GFP_KERNEL);
543 if (!req)
544 goto err;
545
546 req->complete = pn_rx_complete;
547 fp->out_reqv[i] = req;
548 }
549
550 /* Outgoing USB requests */
551 fp->in_req = usb_ep_alloc_request(fp->in_ep, GFP_KERNEL);
552 if (!fp->in_req)
553 goto err;
554
555 INFO(cdev, "USB CDC Phonet function\n");
556 INFO(cdev, "using %s, OUT %s, IN %s\n", cdev->gadget->name,
557 fp->out_ep->name, fp->in_ep->name);
558 return 0;
559
560 err:
561 if (fp->out_ep)
562 fp->out_ep->driver_data = NULL;
563 if (fp->in_ep)
564 fp->in_ep->driver_data = NULL;
565 ERROR(cdev, "USB CDC Phonet: cannot autoconfigure\n");
566 return status;
567 }
568
569 static void
pn_unbind(struct usb_configuration * c,struct usb_function * f)570 pn_unbind(struct usb_configuration *c, struct usb_function *f)
571 {
572 struct f_phonet *fp = func_to_pn(f);
573 int i;
574
575 /* We are already disconnected */
576 if (fp->in_req)
577 usb_ep_free_request(fp->in_ep, fp->in_req);
578 for (i = 0; i < phonet_rxq_size; i++)
579 if (fp->out_reqv[i])
580 usb_ep_free_request(fp->out_ep, fp->out_reqv[i]);
581
582 kfree(fp);
583 }
584
585 /*-------------------------------------------------------------------------*/
586
587 static struct net_device *dev;
588
phonet_bind_config(struct usb_configuration * c)589 int __init phonet_bind_config(struct usb_configuration *c)
590 {
591 struct f_phonet *fp;
592 int err, size;
593
594 size = sizeof(*fp) + (phonet_rxq_size * sizeof(struct usb_request *));
595 fp = kzalloc(size, GFP_KERNEL);
596 if (!fp)
597 return -ENOMEM;
598
599 fp->dev = dev;
600 fp->function.name = "phonet";
601 fp->function.bind = pn_bind;
602 fp->function.unbind = pn_unbind;
603 fp->function.set_alt = pn_set_alt;
604 fp->function.get_alt = pn_get_alt;
605 fp->function.disable = pn_disconnect;
606 spin_lock_init(&fp->rx.lock);
607
608 err = usb_add_function(c, &fp->function);
609 if (err)
610 kfree(fp);
611 return err;
612 }
613
gphonet_setup(struct usb_gadget * gadget)614 int __init gphonet_setup(struct usb_gadget *gadget)
615 {
616 struct phonet_port *port;
617 int err;
618
619 /* Create net device */
620 BUG_ON(dev);
621 dev = alloc_netdev(sizeof(*port), "upnlink%d", pn_net_setup);
622 if (!dev)
623 return -ENOMEM;
624
625 port = netdev_priv(dev);
626 spin_lock_init(&port->lock);
627 netif_carrier_off(dev);
628 SET_NETDEV_DEV(dev, &gadget->dev);
629
630 err = register_netdev(dev);
631 if (err)
632 free_netdev(dev);
633 return err;
634 }
635
gphonet_cleanup(void)636 void gphonet_cleanup(void)
637 {
638 unregister_netdev(dev);
639 }
640