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10#include <linux/mm.h>
11#include <linux/slab.h>
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/device.h>
15
16#include <linux/netdevice.h>
17#include <linux/if_ether.h>
18#include <linux/if_phonet.h>
19#include <linux/if_arp.h>
20
21#include <linux/usb/ch9.h>
22#include <linux/usb/cdc.h>
23#include <linux/usb/composite.h>
24
25#include "u_phonet.h"
26#include "u_ether.h"
27
28#define PN_MEDIA_USB 0x1B
29#define MAXPACKET 512
30#if (PAGE_SIZE % MAXPACKET)
31#error MAXPACKET must divide PAGE_SIZE!
32#endif
33
34
35
36struct phonet_port {
37 struct f_phonet *usb;
38 spinlock_t lock;
39};
40
41struct f_phonet {
42 struct usb_function function;
43 struct {
44 struct sk_buff *skb;
45 spinlock_t lock;
46 } rx;
47 struct net_device *dev;
48 struct usb_ep *in_ep, *out_ep;
49
50 struct usb_request *in_req;
51 struct usb_request *out_reqv[];
52};
53
54static int phonet_rxq_size = 17;
55
56static inline struct f_phonet *func_to_pn(struct usb_function *f)
57{
58 return container_of(f, struct f_phonet, function);
59}
60
61
62
63#define USB_CDC_SUBCLASS_PHONET 0xfe
64#define USB_CDC_PHONET_TYPE 0xab
65
66static struct usb_interface_descriptor
67pn_control_intf_desc = {
68 .bLength = sizeof pn_control_intf_desc,
69 .bDescriptorType = USB_DT_INTERFACE,
70
71
72 .bInterfaceClass = USB_CLASS_COMM,
73 .bInterfaceSubClass = USB_CDC_SUBCLASS_PHONET,
74};
75
76static const struct usb_cdc_header_desc
77pn_header_desc = {
78 .bLength = sizeof pn_header_desc,
79 .bDescriptorType = USB_DT_CS_INTERFACE,
80 .bDescriptorSubType = USB_CDC_HEADER_TYPE,
81 .bcdCDC = cpu_to_le16(0x0110),
82};
83
84static const struct usb_cdc_header_desc
85pn_phonet_desc = {
86 .bLength = sizeof pn_phonet_desc,
87 .bDescriptorType = USB_DT_CS_INTERFACE,
88 .bDescriptorSubType = USB_CDC_PHONET_TYPE,
89 .bcdCDC = cpu_to_le16(0x1505),
90};
91
92static struct usb_cdc_union_desc
93pn_union_desc = {
94 .bLength = sizeof pn_union_desc,
95 .bDescriptorType = USB_DT_CS_INTERFACE,
96 .bDescriptorSubType = USB_CDC_UNION_TYPE,
97
98
99
100};
101
102static struct usb_interface_descriptor
103pn_data_nop_intf_desc = {
104 .bLength = sizeof pn_data_nop_intf_desc,
105 .bDescriptorType = USB_DT_INTERFACE,
106
107
108 .bAlternateSetting = 0,
109 .bNumEndpoints = 0,
110 .bInterfaceClass = USB_CLASS_CDC_DATA,
111};
112
113static struct usb_interface_descriptor
114pn_data_intf_desc = {
115 .bLength = sizeof pn_data_intf_desc,
116 .bDescriptorType = USB_DT_INTERFACE,
117
118
119 .bAlternateSetting = 1,
120 .bNumEndpoints = 2,
121 .bInterfaceClass = USB_CLASS_CDC_DATA,
122};
123
124static struct usb_endpoint_descriptor
125pn_fs_sink_desc = {
126 .bLength = USB_DT_ENDPOINT_SIZE,
127 .bDescriptorType = USB_DT_ENDPOINT,
128
129 .bEndpointAddress = USB_DIR_OUT,
130 .bmAttributes = USB_ENDPOINT_XFER_BULK,
131};
132
133static struct usb_endpoint_descriptor
134pn_hs_sink_desc = {
135 .bLength = USB_DT_ENDPOINT_SIZE,
136 .bDescriptorType = USB_DT_ENDPOINT,
137
138 .bEndpointAddress = USB_DIR_OUT,
139 .bmAttributes = USB_ENDPOINT_XFER_BULK,
140 .wMaxPacketSize = cpu_to_le16(MAXPACKET),
141};
142
143static struct usb_endpoint_descriptor
144pn_fs_source_desc = {
145 .bLength = USB_DT_ENDPOINT_SIZE,
146 .bDescriptorType = USB_DT_ENDPOINT,
147
148 .bEndpointAddress = USB_DIR_IN,
149 .bmAttributes = USB_ENDPOINT_XFER_BULK,
150};
151
152static struct usb_endpoint_descriptor
153pn_hs_source_desc = {
154 .bLength = USB_DT_ENDPOINT_SIZE,
155 .bDescriptorType = USB_DT_ENDPOINT,
156
157 .bEndpointAddress = USB_DIR_IN,
158 .bmAttributes = USB_ENDPOINT_XFER_BULK,
159 .wMaxPacketSize = cpu_to_le16(512),
160};
161
162static struct usb_descriptor_header *fs_pn_function[] = {
163 (struct usb_descriptor_header *) &pn_control_intf_desc,
164 (struct usb_descriptor_header *) &pn_header_desc,
165 (struct usb_descriptor_header *) &pn_phonet_desc,
166 (struct usb_descriptor_header *) &pn_union_desc,
167 (struct usb_descriptor_header *) &pn_data_nop_intf_desc,
168 (struct usb_descriptor_header *) &pn_data_intf_desc,
169 (struct usb_descriptor_header *) &pn_fs_sink_desc,
170 (struct usb_descriptor_header *) &pn_fs_source_desc,
171 NULL,
172};
173
174static struct usb_descriptor_header *hs_pn_function[] = {
175 (struct usb_descriptor_header *) &pn_control_intf_desc,
176 (struct usb_descriptor_header *) &pn_header_desc,
177 (struct usb_descriptor_header *) &pn_phonet_desc,
178 (struct usb_descriptor_header *) &pn_union_desc,
179 (struct usb_descriptor_header *) &pn_data_nop_intf_desc,
180 (struct usb_descriptor_header *) &pn_data_intf_desc,
181 (struct usb_descriptor_header *) &pn_hs_sink_desc,
182 (struct usb_descriptor_header *) &pn_hs_source_desc,
183 NULL,
184};
185
186
187
188static int pn_net_open(struct net_device *dev)
189{
190 netif_wake_queue(dev);
191 return 0;
192}
193
194static int pn_net_close(struct net_device *dev)
195{
196 netif_stop_queue(dev);
197 return 0;
198}
199
200static void pn_tx_complete(struct usb_ep *ep, struct usb_request *req)
201{
202 struct f_phonet *fp = ep->driver_data;
203 struct net_device *dev = fp->dev;
204 struct sk_buff *skb = req->context;
205
206 switch (req->status) {
207 case 0:
208 dev->stats.tx_packets++;
209 dev->stats.tx_bytes += skb->len;
210 break;
211
212 case -ESHUTDOWN:
213 case -ECONNRESET:
214 dev->stats.tx_aborted_errors++;
215 fallthrough;
216 default:
217 dev->stats.tx_errors++;
218 }
219
220 dev_kfree_skb_any(skb);
221 netif_wake_queue(dev);
222}
223
224static netdev_tx_t 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))
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
252out_unlock:
253 spin_unlock_irqrestore(&port->lock, flags);
254out:
255 if (unlikely(skb)) {
256 dev_kfree_skb(skb);
257 dev->stats.tx_dropped++;
258 }
259 return NETDEV_TX_OK;
260}
261
262static const struct net_device_ops pn_netdev_ops = {
263 .ndo_open = pn_net_open,
264 .ndo_stop = pn_net_close,
265 .ndo_start_xmit = pn_net_xmit,
266};
267
268static void pn_net_setup(struct net_device *dev)
269{
270 dev->features = 0;
271 dev->type = ARPHRD_PHONET;
272 dev->flags = IFF_POINTOPOINT | IFF_NOARP;
273 dev->mtu = PHONET_DEV_MTU;
274 dev->min_mtu = PHONET_MIN_MTU;
275 dev->max_mtu = PHONET_MAX_MTU;
276 dev->hard_header_len = 1;
277 dev->dev_addr[0] = PN_MEDIA_USB;
278 dev->addr_len = 1;
279 dev->tx_queue_len = 1;
280
281 dev->netdev_ops = &pn_netdev_ops;
282 dev->needs_free_netdev = true;
283 dev->header_ops = &phonet_header_ops;
284}
285
286
287
288
289
290
291static int
292pn_rx_submit(struct f_phonet *fp, struct usb_request *req, gfp_t gfp_flags)
293{
294 struct page *page;
295 int err;
296
297 page = __dev_alloc_page(gfp_flags | __GFP_NOMEMALLOC);
298 if (!page)
299 return -ENOMEM;
300
301 req->buf = page_address(page);
302 req->length = PAGE_SIZE;
303 req->context = page;
304
305 err = usb_ep_queue(fp->out_ep, req, gfp_flags);
306 if (unlikely(err))
307 put_page(page);
308 return err;
309}
310
311static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req)
312{
313 struct f_phonet *fp = ep->driver_data;
314 struct net_device *dev = fp->dev;
315 struct page *page = req->context;
316 struct sk_buff *skb;
317 unsigned long flags;
318 int status = req->status;
319
320 switch (status) {
321 case 0:
322 spin_lock_irqsave(&fp->rx.lock, flags);
323 skb = fp->rx.skb;
324 if (!skb)
325 skb = fp->rx.skb = netdev_alloc_skb(dev, 12);
326 if (req->actual < req->length)
327 fp->rx.skb = NULL;
328 spin_unlock_irqrestore(&fp->rx.lock, flags);
329
330 if (unlikely(!skb))
331 break;
332
333 if (skb->len == 0) {
334 skb->protocol = htons(ETH_P_PHONET);
335 skb_reset_mac_header(skb);
336
337 skb_put_data(skb, page_address(page), 1);
338 }
339
340 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page,
341 skb->len <= 1, req->actual, PAGE_SIZE);
342 page = NULL;
343
344 if (req->actual < req->length) {
345 skb->dev = dev;
346 dev->stats.rx_packets++;
347 dev->stats.rx_bytes += skb->len;
348
349 netif_rx(skb);
350 }
351 break;
352
353
354 case -ESHUTDOWN:
355 case -ECONNABORTED:
356 case -ECONNRESET:
357 req = NULL;
358 break;
359
360
361 case -EOVERFLOW:
362 dev->stats.rx_over_errors++;
363 fallthrough;
364 default:
365 dev->stats.rx_errors++;
366 break;
367 }
368
369 if (page)
370 put_page(page);
371 if (req)
372 pn_rx_submit(fp, req, GFP_ATOMIC);
373}
374
375
376
377static void __pn_reset(struct usb_function *f)
378{
379 struct f_phonet *fp = func_to_pn(f);
380 struct net_device *dev = fp->dev;
381 struct phonet_port *port = netdev_priv(dev);
382
383 netif_carrier_off(dev);
384 port->usb = NULL;
385
386 usb_ep_disable(fp->out_ep);
387 usb_ep_disable(fp->in_ep);
388 if (fp->rx.skb) {
389 dev_kfree_skb_irq(fp->rx.skb);
390 fp->rx.skb = NULL;
391 }
392}
393
394static int pn_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
395{
396 struct f_phonet *fp = func_to_pn(f);
397 struct usb_gadget *gadget = fp->function.config->cdev->gadget;
398
399 if (intf == pn_control_intf_desc.bInterfaceNumber)
400
401 return (alt > 0) ? -EINVAL : 0;
402
403 if (intf == pn_data_intf_desc.bInterfaceNumber) {
404 struct net_device *dev = fp->dev;
405 struct phonet_port *port = netdev_priv(dev);
406
407
408 if (alt > 1)
409 return -EINVAL;
410
411 spin_lock(&port->lock);
412
413 if (fp->in_ep->enabled)
414 __pn_reset(f);
415
416 if (alt == 1) {
417 int i;
418
419 if (config_ep_by_speed(gadget, f, fp->in_ep) ||
420 config_ep_by_speed(gadget, f, fp->out_ep)) {
421 fp->in_ep->desc = NULL;
422 fp->out_ep->desc = NULL;
423 spin_unlock(&port->lock);
424 return -EINVAL;
425 }
426 usb_ep_enable(fp->out_ep);
427 usb_ep_enable(fp->in_ep);
428
429 port->usb = fp;
430 fp->out_ep->driver_data = fp;
431 fp->in_ep->driver_data = fp;
432
433 netif_carrier_on(dev);
434 for (i = 0; i < phonet_rxq_size; i++)
435 pn_rx_submit(fp, fp->out_reqv[i], GFP_ATOMIC);
436 }
437 spin_unlock(&port->lock);
438 return 0;
439 }
440
441 return -EINVAL;
442}
443
444static int pn_get_alt(struct usb_function *f, unsigned intf)
445{
446 struct f_phonet *fp = func_to_pn(f);
447
448 if (intf == pn_control_intf_desc.bInterfaceNumber)
449 return 0;
450
451 if (intf == pn_data_intf_desc.bInterfaceNumber) {
452 struct phonet_port *port = netdev_priv(fp->dev);
453 u8 alt;
454
455 spin_lock(&port->lock);
456 alt = port->usb != NULL;
457 spin_unlock(&port->lock);
458 return alt;
459 }
460
461 return -EINVAL;
462}
463
464static void pn_disconnect(struct usb_function *f)
465{
466 struct f_phonet *fp = func_to_pn(f);
467 struct phonet_port *port = netdev_priv(fp->dev);
468 unsigned long flags;
469
470
471 spin_lock_irqsave(&port->lock, flags);
472 __pn_reset(f);
473 spin_unlock_irqrestore(&port->lock, flags);
474}
475
476
477
478static int pn_bind(struct usb_configuration *c, struct usb_function *f)
479{
480 struct usb_composite_dev *cdev = c->cdev;
481 struct usb_gadget *gadget = cdev->gadget;
482 struct f_phonet *fp = func_to_pn(f);
483 struct usb_ep *ep;
484 int status, i;
485
486 struct f_phonet_opts *phonet_opts;
487
488 phonet_opts = container_of(f->fi, struct f_phonet_opts, func_inst);
489
490
491
492
493
494
495
496
497 if (!phonet_opts->bound) {
498 gphonet_set_gadget(phonet_opts->net, gadget);
499 status = gphonet_register_netdev(phonet_opts->net);
500 if (status)
501 return status;
502 phonet_opts->bound = true;
503 }
504
505
506 status = usb_interface_id(c, f);
507 if (status < 0)
508 goto err;
509 pn_control_intf_desc.bInterfaceNumber = status;
510 pn_union_desc.bMasterInterface0 = status;
511
512 status = usb_interface_id(c, f);
513 if (status < 0)
514 goto err;
515 pn_data_nop_intf_desc.bInterfaceNumber = status;
516 pn_data_intf_desc.bInterfaceNumber = status;
517 pn_union_desc.bSlaveInterface0 = status;
518
519
520 status = -ENODEV;
521 ep = usb_ep_autoconfig(gadget, &pn_fs_sink_desc);
522 if (!ep)
523 goto err;
524 fp->out_ep = ep;
525
526 ep = usb_ep_autoconfig(gadget, &pn_fs_source_desc);
527 if (!ep)
528 goto err;
529 fp->in_ep = ep;
530
531 pn_hs_sink_desc.bEndpointAddress = pn_fs_sink_desc.bEndpointAddress;
532 pn_hs_source_desc.bEndpointAddress = pn_fs_source_desc.bEndpointAddress;
533
534
535 status = usb_assign_descriptors(f, fs_pn_function, hs_pn_function,
536 NULL, NULL);
537 if (status)
538 goto err;
539
540
541 status = -ENOMEM;
542 for (i = 0; i < phonet_rxq_size; i++) {
543 struct usb_request *req;
544
545 req = usb_ep_alloc_request(fp->out_ep, GFP_KERNEL);
546 if (!req)
547 goto err_req;
548
549 req->complete = pn_rx_complete;
550 fp->out_reqv[i] = req;
551 }
552
553
554 fp->in_req = usb_ep_alloc_request(fp->in_ep, GFP_KERNEL);
555 if (!fp->in_req)
556 goto err_req;
557
558 INFO(cdev, "USB CDC Phonet function\n");
559 INFO(cdev, "using %s, OUT %s, IN %s\n", cdev->gadget->name,
560 fp->out_ep->name, fp->in_ep->name);
561 return 0;
562
563err_req:
564 for (i = 0; i < phonet_rxq_size && fp->out_reqv[i]; i++)
565 usb_ep_free_request(fp->out_ep, fp->out_reqv[i]);
566 usb_free_all_descriptors(f);
567err:
568 ERROR(cdev, "USB CDC Phonet: cannot autoconfigure\n");
569 return status;
570}
571
572static inline struct f_phonet_opts *to_f_phonet_opts(struct config_item *item)
573{
574 return container_of(to_config_group(item), struct f_phonet_opts,
575 func_inst.group);
576}
577
578static void phonet_attr_release(struct config_item *item)
579{
580 struct f_phonet_opts *opts = to_f_phonet_opts(item);
581
582 usb_put_function_instance(&opts->func_inst);
583}
584
585static struct configfs_item_operations phonet_item_ops = {
586 .release = phonet_attr_release,
587};
588
589static ssize_t f_phonet_ifname_show(struct config_item *item, char *page)
590{
591 return gether_get_ifname(to_f_phonet_opts(item)->net, page, PAGE_SIZE);
592}
593
594CONFIGFS_ATTR_RO(f_phonet_, ifname);
595
596static struct configfs_attribute *phonet_attrs[] = {
597 &f_phonet_attr_ifname,
598 NULL,
599};
600
601static const struct config_item_type phonet_func_type = {
602 .ct_item_ops = &phonet_item_ops,
603 .ct_attrs = phonet_attrs,
604 .ct_owner = THIS_MODULE,
605};
606
607static void phonet_free_inst(struct usb_function_instance *f)
608{
609 struct f_phonet_opts *opts;
610
611 opts = container_of(f, struct f_phonet_opts, func_inst);
612 if (opts->bound)
613 gphonet_cleanup(opts->net);
614 else
615 free_netdev(opts->net);
616 kfree(opts);
617}
618
619static struct usb_function_instance *phonet_alloc_inst(void)
620{
621 struct f_phonet_opts *opts;
622
623 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
624 if (!opts)
625 return ERR_PTR(-ENOMEM);
626
627 opts->func_inst.free_func_inst = phonet_free_inst;
628 opts->net = gphonet_setup_default();
629 if (IS_ERR(opts->net)) {
630 struct net_device *net = opts->net;
631 kfree(opts);
632 return ERR_CAST(net);
633 }
634
635 config_group_init_type_name(&opts->func_inst.group, "",
636 &phonet_func_type);
637
638 return &opts->func_inst;
639}
640
641static void phonet_free(struct usb_function *f)
642{
643 struct f_phonet *phonet;
644
645 phonet = func_to_pn(f);
646 kfree(phonet);
647}
648
649static void pn_unbind(struct usb_configuration *c, struct usb_function *f)
650{
651 struct f_phonet *fp = func_to_pn(f);
652 int i;
653
654
655 if (fp->in_req)
656 usb_ep_free_request(fp->in_ep, fp->in_req);
657 for (i = 0; i < phonet_rxq_size; i++)
658 if (fp->out_reqv[i])
659 usb_ep_free_request(fp->out_ep, fp->out_reqv[i]);
660
661 usb_free_all_descriptors(f);
662}
663
664static struct usb_function *phonet_alloc(struct usb_function_instance *fi)
665{
666 struct f_phonet *fp;
667 struct f_phonet_opts *opts;
668 int size;
669
670 size = sizeof(*fp) + (phonet_rxq_size * sizeof(struct usb_request *));
671 fp = kzalloc(size, GFP_KERNEL);
672 if (!fp)
673 return ERR_PTR(-ENOMEM);
674
675 opts = container_of(fi, struct f_phonet_opts, func_inst);
676
677 fp->dev = opts->net;
678 fp->function.name = "phonet";
679 fp->function.bind = pn_bind;
680 fp->function.unbind = pn_unbind;
681 fp->function.set_alt = pn_set_alt;
682 fp->function.get_alt = pn_get_alt;
683 fp->function.disable = pn_disconnect;
684 fp->function.free_func = phonet_free;
685 spin_lock_init(&fp->rx.lock);
686
687 return &fp->function;
688}
689
690struct net_device *gphonet_setup_default(void)
691{
692 struct net_device *dev;
693 struct phonet_port *port;
694
695
696 dev = alloc_netdev(sizeof(*port), "upnlink%d", NET_NAME_UNKNOWN,
697 pn_net_setup);
698 if (!dev)
699 return ERR_PTR(-ENOMEM);
700
701 port = netdev_priv(dev);
702 spin_lock_init(&port->lock);
703 netif_carrier_off(dev);
704
705 return dev;
706}
707
708void gphonet_set_gadget(struct net_device *net, struct usb_gadget *g)
709{
710 SET_NETDEV_DEV(net, &g->dev);
711}
712
713int gphonet_register_netdev(struct net_device *net)
714{
715 int status;
716
717 status = register_netdev(net);
718 if (status)
719 free_netdev(net);
720
721 return status;
722}
723
724void gphonet_cleanup(struct net_device *dev)
725{
726 unregister_netdev(dev);
727}
728
729DECLARE_USB_FUNCTION_INIT(phonet, phonet_alloc_inst, phonet_alloc);
730MODULE_AUTHOR("Rémi Denis-Courmont");
731MODULE_LICENSE("GPL");
732
