USB: misc/vstusb, fix lock imbalance
[linux-2.6] / drivers / usb / gadget / f_phonet.c
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
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
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
196 static int pn_net_close(struct net_device *dev)
197 {
198         netif_stop_queue(dev);
199         return 0;
200 }
201
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
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
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
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
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
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
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
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
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
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
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
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
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
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
622 void gphonet_cleanup(void)
623 {
624         unregister_netdev(dev);
625 }