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
13 #include <linux/mm.h>
14 #include <linux/slab.h>
15 #include <linux/kernel.h>
16 #include <linux/device.h>
17
18 #include <linux/netdevice.h>
19 #include <linux/if_ether.h>
20 #include <linux/if_phonet.h>
21 #include <linux/if_arp.h>
22
23 #include <linux/usb/ch9.h>
24 #include <linux/usb/cdc.h>
25 #include <linux/usb/composite.h>
26
27 #include "u_phonet.h"
28
29 #define PN_MEDIA_USB 0x1B
30 #define MAXPACKET 512
31 #if (PAGE_SIZE % MAXPACKET)
32 #error MAXPACKET must divide PAGE_SIZE!
33 #endif
34
35 /*-------------------------------------------------------------------------*/
36
37 struct phonet_port {
38 struct f_phonet *usb;
39 spinlock_t lock;
40 };
41
42 struct f_phonet {
43 struct usb_function function;
44 struct {
45 struct sk_buff *skb;
46 spinlock_t lock;
47 } rx;
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 = 17;
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 = 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 = 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 = cpu_to_le16(MAXPACKET),
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 = 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 netif_wake_queue(dev);
192 return 0;
193 }
194
pn_net_close(struct net_device * dev)195 static int pn_net_close(struct net_device *dev)
196 {
197 netif_stop_queue(dev);
198 return 0;
199 }
200
pn_tx_complete(struct usb_ep * ep,struct usb_request * req)201 static void pn_tx_complete(struct usb_ep *ep, struct usb_request *req)
202 {
203 struct f_phonet *fp = ep->driver_data;
204 struct net_device *dev = fp->dev;
205 struct sk_buff *skb = req->context;
206
207 switch (req->status) {
208 case 0:
209 dev->stats.tx_packets++;
210 dev->stats.tx_bytes += skb->len;
211 break;
212
213 case -ESHUTDOWN: /* disconnected */
214 case -ECONNRESET: /* disabled */
215 dev->stats.tx_aborted_errors++;
216 default:
217 dev->stats.tx_errors++;
218 }
219
220 dev_kfree_skb_any(skb);
221 netif_wake_queue(dev);
222 }
223
pn_net_xmit(struct sk_buff * skb,struct net_device * dev)224 static int pn_net_xmit(struct sk_buff *skb, struct net_device *dev)
225 {
226 struct phonet_port *port = netdev_priv(dev);
227 struct f_phonet *fp;
228 struct usb_request *req;
229 unsigned long flags;
230
231 if (skb->protocol != htons(ETH_P_PHONET))
232 goto out;
233
234 spin_lock_irqsave(&port->lock, flags);
235 fp = port->usb;
236 if (unlikely(!fp)) /* race with carrier loss */
237 goto out_unlock;
238
239 req = fp->in_req;
240 req->buf = skb->data;
241 req->length = skb->len;
242 req->complete = pn_tx_complete;
243 req->zero = 1;
244 req->context = skb;
245
246 if (unlikely(usb_ep_queue(fp->in_ep, req, GFP_ATOMIC)))
247 goto out_unlock;
248
249 netif_stop_queue(dev);
250 skb = NULL;
251
252 out_unlock:
253 spin_unlock_irqrestore(&port->lock, flags);
254 out:
255 if (unlikely(skb)) {
256 dev_kfree_skb(skb);
257 dev->stats.tx_dropped++;
258 }
259 return NETDEV_TX_OK;
260 }
261
pn_net_mtu(struct net_device * dev,int new_mtu)262 static int pn_net_mtu(struct net_device *dev, int new_mtu)
263 {
264 if ((new_mtu < PHONET_MIN_MTU) || (new_mtu > PHONET_MAX_MTU))
265 return -EINVAL;
266 dev->mtu = new_mtu;
267 return 0;
268 }
269
270 static const struct net_device_ops pn_netdev_ops = {
271 .ndo_open = pn_net_open,
272 .ndo_stop = pn_net_close,
273 .ndo_start_xmit = pn_net_xmit,
274 .ndo_change_mtu = pn_net_mtu,
275 };
276
pn_net_setup(struct net_device * dev)277 static void pn_net_setup(struct net_device *dev)
278 {
279 dev->features = 0;
280 dev->type = ARPHRD_PHONET;
281 dev->flags = IFF_POINTOPOINT | IFF_NOARP;
282 dev->mtu = PHONET_DEV_MTU;
283 dev->hard_header_len = 1;
284 dev->dev_addr[0] = PN_MEDIA_USB;
285 dev->addr_len = 1;
286 dev->tx_queue_len = 1;
287
288 dev->netdev_ops = &pn_netdev_ops;
289 dev->destructor = free_netdev;
290 dev->header_ops = &phonet_header_ops;
291 }
292
293 /*-------------------------------------------------------------------------*/
294
295 /*
296 * Queue buffer for data from the host
297 */
298 static int
pn_rx_submit(struct f_phonet * fp,struct usb_request * req,gfp_t gfp_flags)299 pn_rx_submit(struct f_phonet *fp, struct usb_request *req, gfp_t gfp_flags)
300 {
301 struct page *page;
302 int err;
303
304 page = alloc_page(gfp_flags);
305 if (!page)
306 return -ENOMEM;
307
308 req->buf = page_address(page);
309 req->length = PAGE_SIZE;
310 req->context = page;
311
312 err = usb_ep_queue(fp->out_ep, req, gfp_flags);
313 if (unlikely(err))
314 put_page(page);
315 return err;
316 }
317
pn_rx_complete(struct usb_ep * ep,struct usb_request * req)318 static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req)
319 {
320 struct f_phonet *fp = ep->driver_data;
321 struct net_device *dev = fp->dev;
322 struct page *page = req->context;
323 struct sk_buff *skb;
324 unsigned long flags;
325 int status = req->status;
326
327 switch (status) {
328 case 0:
329 spin_lock_irqsave(&fp->rx.lock, flags);
330 skb = fp->rx.skb;
331 if (!skb)
332 skb = fp->rx.skb = netdev_alloc_skb(dev, 12);
333 if (req->actual < req->length) /* Last fragment */
334 fp->rx.skb = NULL;
335 spin_unlock_irqrestore(&fp->rx.lock, flags);
336
337 if (unlikely(!skb))
338 break;
339
340 if (skb->len == 0) { /* First fragment */
341 skb->protocol = htons(ETH_P_PHONET);
342 skb_reset_mac_header(skb);
343 /* Can't use pskb_pull() on page in IRQ */
344 memcpy(skb_put(skb, 1), page_address(page), 1);
345 }
346
347 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page,
348 skb->len <= 1, req->actual, PAGE_SIZE);
349 page = NULL;
350
351 if (req->actual < req->length) { /* Last fragment */
352 skb->dev = dev;
353 dev->stats.rx_packets++;
354 dev->stats.rx_bytes += skb->len;
355
356 netif_rx(skb);
357 }
358 break;
359
360 /* Do not resubmit in these cases: */
361 case -ESHUTDOWN: /* disconnect */
362 case -ECONNABORTED: /* hw reset */
363 case -ECONNRESET: /* dequeued (unlink or netif down) */
364 req = NULL;
365 break;
366
367 /* Do resubmit in these cases: */
368 case -EOVERFLOW: /* request buffer overflow */
369 dev->stats.rx_over_errors++;
370 default:
371 dev->stats.rx_errors++;
372 break;
373 }
374
375 if (page)
376 put_page(page);
377 if (req)
378 pn_rx_submit(fp, req, GFP_ATOMIC | __GFP_COLD);
379 }
380
381 /*-------------------------------------------------------------------------*/
382
__pn_reset(struct usb_function * f)383 static void __pn_reset(struct usb_function *f)
384 {
385 struct f_phonet *fp = func_to_pn(f);
386 struct net_device *dev = fp->dev;
387 struct phonet_port *port = netdev_priv(dev);
388
389 netif_carrier_off(dev);
390 port->usb = NULL;
391
392 usb_ep_disable(fp->out_ep);
393 usb_ep_disable(fp->in_ep);
394 if (fp->rx.skb) {
395 dev_kfree_skb_irq(fp->rx.skb);
396 fp->rx.skb = NULL;
397 }
398 }
399
pn_set_alt(struct usb_function * f,unsigned intf,unsigned alt)400 static int pn_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
401 {
402 struct f_phonet *fp = func_to_pn(f);
403 struct usb_gadget *gadget = fp->function.config->cdev->gadget;
404
405 if (intf == pn_control_intf_desc.bInterfaceNumber)
406 /* control interface, no altsetting */
407 return (alt > 0) ? -EINVAL : 0;
408
409 if (intf == pn_data_intf_desc.bInterfaceNumber) {
410 struct net_device *dev = fp->dev;
411 struct phonet_port *port = netdev_priv(dev);
412
413 /* data intf (0: inactive, 1: active) */
414 if (alt > 1)
415 return -EINVAL;
416
417 spin_lock(&port->lock);
418 __pn_reset(f);
419 if (alt == 1) {
420 int i;
421
422 if (config_ep_by_speed(gadget, f, fp->in_ep) ||
423 config_ep_by_speed(gadget, f, fp->out_ep)) {
424 fp->in_ep->desc = NULL;
425 fp->out_ep->desc = NULL;
426 spin_unlock(&port->lock);
427 return -EINVAL;
428 }
429 usb_ep_enable(fp->out_ep);
430 usb_ep_enable(fp->in_ep);
431
432 port->usb = fp;
433 fp->out_ep->driver_data = fp;
434 fp->in_ep->driver_data = fp;
435
436 netif_carrier_on(dev);
437 for (i = 0; i < phonet_rxq_size; i++)
438 pn_rx_submit(fp, fp->out_reqv[i], GFP_ATOMIC | __GFP_COLD);
439 }
440 spin_unlock(&port->lock);
441 return 0;
442 }
443
444 return -EINVAL;
445 }
446
pn_get_alt(struct usb_function * f,unsigned intf)447 static int pn_get_alt(struct usb_function *f, unsigned intf)
448 {
449 struct f_phonet *fp = func_to_pn(f);
450
451 if (intf == pn_control_intf_desc.bInterfaceNumber)
452 return 0;
453
454 if (intf == pn_data_intf_desc.bInterfaceNumber) {
455 struct phonet_port *port = netdev_priv(fp->dev);
456 u8 alt;
457
458 spin_lock(&port->lock);
459 alt = port->usb != NULL;
460 spin_unlock(&port->lock);
461 return alt;
462 }
463
464 return -EINVAL;
465 }
466
pn_disconnect(struct usb_function * f)467 static void pn_disconnect(struct usb_function *f)
468 {
469 struct f_phonet *fp = func_to_pn(f);
470 struct phonet_port *port = netdev_priv(fp->dev);
471 unsigned long flags;
472
473 /* remain disabled until set_alt */
474 spin_lock_irqsave(&port->lock, flags);
475 __pn_reset(f);
476 spin_unlock_irqrestore(&port->lock, flags);
477 }
478
479 /*-------------------------------------------------------------------------*/
480
481 static __init
pn_bind(struct usb_configuration * c,struct usb_function * f)482 int pn_bind(struct usb_configuration *c, struct usb_function *f)
483 {
484 struct usb_composite_dev *cdev = c->cdev;
485 struct usb_gadget *gadget = cdev->gadget;
486 struct f_phonet *fp = func_to_pn(f);
487 struct usb_ep *ep;
488 int status, i;
489
490 /* Reserve interface IDs */
491 status = usb_interface_id(c, f);
492 if (status < 0)
493 goto err;
494 pn_control_intf_desc.bInterfaceNumber = status;
495 pn_union_desc.bMasterInterface0 = status;
496
497 status = usb_interface_id(c, f);
498 if (status < 0)
499 goto err;
500 pn_data_nop_intf_desc.bInterfaceNumber = status;
501 pn_data_intf_desc.bInterfaceNumber = status;
502 pn_union_desc.bSlaveInterface0 = status;
503
504 /* Reserve endpoints */
505 status = -ENODEV;
506 ep = usb_ep_autoconfig(gadget, &pn_fs_sink_desc);
507 if (!ep)
508 goto err;
509 fp->out_ep = ep;
510 ep->driver_data = fp; /* Claim */
511
512 ep = usb_ep_autoconfig(gadget, &pn_fs_source_desc);
513 if (!ep)
514 goto err;
515 fp->in_ep = ep;
516 ep->driver_data = fp; /* Claim */
517
518 pn_hs_sink_desc.bEndpointAddress =
519 pn_fs_sink_desc.bEndpointAddress;
520 pn_hs_source_desc.bEndpointAddress =
521 pn_fs_source_desc.bEndpointAddress;
522
523 /* Do not try to bind Phonet twice... */
524 fp->function.descriptors = fs_pn_function;
525 fp->function.hs_descriptors = hs_pn_function;
526
527 /* Incoming USB requests */
528 status = -ENOMEM;
529 for (i = 0; i < phonet_rxq_size; i++) {
530 struct usb_request *req;
531
532 req = usb_ep_alloc_request(fp->out_ep, GFP_KERNEL);
533 if (!req)
534 goto err_req;
535
536 req->complete = pn_rx_complete;
537 fp->out_reqv[i] = req;
538 }
539
540 /* Outgoing USB requests */
541 fp->in_req = usb_ep_alloc_request(fp->in_ep, GFP_KERNEL);
542 if (!fp->in_req)
543 goto err_req;
544
545 INFO(cdev, "USB CDC Phonet function\n");
546 INFO(cdev, "using %s, OUT %s, IN %s\n", cdev->gadget->name,
547 fp->out_ep->name, fp->in_ep->name);
548 return 0;
549
550 err_req:
551 for (i = 0; i < phonet_rxq_size && fp->out_reqv[i]; i++)
552 usb_ep_free_request(fp->out_ep, fp->out_reqv[i]);
553 err:
554
555 if (fp->out_ep)
556 fp->out_ep->driver_data = NULL;
557 if (fp->in_ep)
558 fp->in_ep->driver_data = NULL;
559 ERROR(cdev, "USB CDC Phonet: cannot autoconfigure\n");
560 return status;
561 }
562
563 static void
pn_unbind(struct usb_configuration * c,struct usb_function * f)564 pn_unbind(struct usb_configuration *c, struct usb_function *f)
565 {
566 struct f_phonet *fp = func_to_pn(f);
567 int i;
568
569 /* We are already disconnected */
570 if (fp->in_req)
571 usb_ep_free_request(fp->in_ep, fp->in_req);
572 for (i = 0; i < phonet_rxq_size; i++)
573 if (fp->out_reqv[i])
574 usb_ep_free_request(fp->out_ep, fp->out_reqv[i]);
575
576 kfree(fp);
577 }
578
579 /*-------------------------------------------------------------------------*/
580
581 static struct net_device *dev;
582
phonet_bind_config(struct usb_configuration * c)583 int __init phonet_bind_config(struct usb_configuration *c)
584 {
585 struct f_phonet *fp;
586 int err, size;
587
588 size = sizeof(*fp) + (phonet_rxq_size * sizeof(struct usb_request *));
589 fp = kzalloc(size, GFP_KERNEL);
590 if (!fp)
591 return -ENOMEM;
592
593 fp->dev = dev;
594 fp->function.name = "phonet";
595 fp->function.bind = pn_bind;
596 fp->function.unbind = pn_unbind;
597 fp->function.set_alt = pn_set_alt;
598 fp->function.get_alt = pn_get_alt;
599 fp->function.disable = pn_disconnect;
600 spin_lock_init(&fp->rx.lock);
601
602 err = usb_add_function(c, &fp->function);
603 if (err)
604 kfree(fp);
605 return err;
606 }
607
gphonet_setup(struct usb_gadget * gadget)608 int __init gphonet_setup(struct usb_gadget *gadget)
609 {
610 struct phonet_port *port;
611 int err;
612
613 /* Create net device */
614 BUG_ON(dev);
615 dev = alloc_netdev(sizeof(*port), "upnlink%d", pn_net_setup);
616 if (!dev)
617 return -ENOMEM;
618
619 port = netdev_priv(dev);
620 spin_lock_init(&port->lock);
621 netif_carrier_off(dev);
622 SET_NETDEV_DEV(dev, &gadget->dev);
623
624 err = register_netdev(dev);
625 if (err)
626 free_netdev(dev);
627 return err;
628 }
629
gphonet_cleanup(void)630 void gphonet_cleanup(void)
631 {
632 unregister_netdev(dev);
633 }
634