1 /*****************************************************************************
2 *
3 * Filename: kingsun-sir.c
4 * Version: 0.1.1
5 * Description: Irda KingSun/DonShine USB Dongle
6 * Status: Experimental
7 * Author: Alex Villacís Lasso <a_villacis@palosanto.com>
8 *
9 * Based on stir4200 and mcs7780 drivers, with (strange?) differences
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 *
24 *****************************************************************************/
25
26 /*
27 * This is my current (2007-04-25) understanding of how this dongle is supposed
28 * to work. This is based on reverse-engineering and examination of the packet
29 * data sent and received by the WinXP driver using USBSnoopy. Feel free to
30 * update here as more of this dongle is known:
31 *
32 * General: Unlike the other USB IrDA dongles, this particular dongle exposes,
33 * not two bulk (in and out) endpoints, but two *interrupt* ones. This dongle,
34 * like the bulk based ones (stir4200.c and mcs7780.c), requires polling in
35 * order to receive data.
36 * Transmission: Just like stir4200, this dongle uses a raw stream of data,
37 * which needs to be wrapped and escaped in a similar way as in stir4200.c.
38 * Reception: Poll-based, as in stir4200. Each read returns the contents of a
39 * 8-byte buffer, of which the first byte (LSB) indicates the number of bytes
40 * (1-7) of valid data contained within the remaining 7 bytes. For example, if
41 * the buffer had the following contents:
42 * 06 ff ff ff c0 01 04 aa
43 * This means that (06) there are 6 bytes of valid data. The byte 0xaa at the
44 * end is garbage (left over from a previous reception) and is discarded.
45 * If a read returns an "impossible" value as the length of valid data (such as
46 * 0x36) in the first byte, then the buffer is uninitialized (as is the case of
47 * first plug-in) and its contents should be discarded. There is currently no
48 * evidence that the top 5 bits of the 1st byte of the buffer can have values
49 * other than 0 once reception begins.
50 * Once valid bytes are collected, the assembled stream is a sequence of
51 * wrapped IrDA frames that is unwrapped and unescaped as in stir4200.c.
52 * BIG FAT WARNING: the dongle does *not* reset the RX buffer in any way after
53 * a successful read from the host, which means that in absence of further
54 * reception, repeated reads from the dongle will return the exact same
55 * contents repeatedly. Attempts to be smart and cache a previous read seem
56 * to result in corrupted packets, so this driver depends on the unwrap logic
57 * to sort out any repeated reads.
58 * Speed change: no commands observed so far to change speed, assumed fixed
59 * 9600bps (SIR).
60 */
61
62 #include <linux/module.h>
63 #include <linux/moduleparam.h>
64 #include <linux/kernel.h>
65 #include <linux/types.h>
66 #include <linux/errno.h>
67 #include <linux/init.h>
68 #include <linux/slab.h>
69 #include <linux/kref.h>
70 #include <linux/usb.h>
71 #include <linux/device.h>
72 #include <linux/crc32.h>
73
74 #include <asm/unaligned.h>
75 #include <asm/byteorder.h>
76 #include <asm/uaccess.h>
77
78 #include <net/irda/irda.h>
79 #include <net/irda/wrapper.h>
80 #include <net/irda/crc.h>
81
82 /*
83 * According to lsusb, 0x07c0 is assigned to
84 * "Code Mercenaries Hard- und Software GmbH"
85 */
86 #define KING_VENDOR_ID 0x07c0
87 #define KING_PRODUCT_ID 0x4200
88
89 /* These are the currently known USB ids */
90 static struct usb_device_id dongles[] = {
91 /* KingSun Co,Ltd IrDA/USB Bridge */
92 { USB_DEVICE(KING_VENDOR_ID, KING_PRODUCT_ID) },
93 { }
94 };
95
96 MODULE_DEVICE_TABLE(usb, dongles);
97
98 #define KINGSUN_MTT 0x07
99
100 #define KINGSUN_FIFO_SIZE 4096
101 #define KINGSUN_EP_IN 0
102 #define KINGSUN_EP_OUT 1
103
104 struct kingsun_cb {
105 struct usb_device *usbdev; /* init: probe_irda */
106 struct net_device *netdev; /* network layer */
107 struct irlap_cb *irlap; /* The link layer we are binded to */
108
109 struct qos_info qos;
110
111 __u8 *in_buf; /* receive buffer */
112 __u8 *out_buf; /* transmit buffer */
113 __u8 max_rx; /* max. atomic read from dongle
114 (usually 8), also size of in_buf */
115 __u8 max_tx; /* max. atomic write to dongle
116 (usually 8) */
117
118 iobuff_t rx_buff; /* receive unwrap state machine */
119 struct timeval rx_time;
120 spinlock_t lock;
121 int receiving;
122
123 __u8 ep_in;
124 __u8 ep_out;
125
126 struct urb *tx_urb;
127 struct urb *rx_urb;
128 };
129
130 /* Callback transmission routine */
kingsun_send_irq(struct urb * urb)131 static void kingsun_send_irq(struct urb *urb)
132 {
133 struct kingsun_cb *kingsun = urb->context;
134 struct net_device *netdev = kingsun->netdev;
135
136 /* in process of stopping, just drop data */
137 if (!netif_running(kingsun->netdev)) {
138 err("kingsun_send_irq: Network not running!");
139 return;
140 }
141
142 /* unlink, shutdown, unplug, other nasties */
143 if (urb->status != 0) {
144 err("kingsun_send_irq: urb asynchronously failed - %d",
145 urb->status);
146 }
147 netif_wake_queue(netdev);
148 }
149
150 /*
151 * Called from net/core when new frame is available.
152 */
kingsun_hard_xmit(struct sk_buff * skb,struct net_device * netdev)153 static int kingsun_hard_xmit(struct sk_buff *skb, struct net_device *netdev)
154 {
155 struct kingsun_cb *kingsun;
156 int wraplen;
157 int ret = 0;
158
159 if (skb == NULL || netdev == NULL)
160 return -EINVAL;
161
162 netif_stop_queue(netdev);
163
164 /* the IRDA wrapping routines don't deal with non linear skb */
165 SKB_LINEAR_ASSERT(skb);
166
167 kingsun = netdev_priv(netdev);
168
169 spin_lock(&kingsun->lock);
170
171 /* Append data to the end of whatever data remains to be transmitted */
172 wraplen = async_wrap_skb(skb,
173 kingsun->out_buf,
174 KINGSUN_FIFO_SIZE);
175
176 /* Calculate how much data can be transmitted in this urb */
177 usb_fill_int_urb(kingsun->tx_urb, kingsun->usbdev,
178 usb_sndintpipe(kingsun->usbdev, kingsun->ep_out),
179 kingsun->out_buf, wraplen, kingsun_send_irq,
180 kingsun, 1);
181
182 if ((ret = usb_submit_urb(kingsun->tx_urb, GFP_ATOMIC))) {
183 err("kingsun_hard_xmit: failed tx_urb submit: %d", ret);
184 switch (ret) {
185 case -ENODEV:
186 case -EPIPE:
187 break;
188 default:
189 netdev->stats.tx_errors++;
190 netif_start_queue(netdev);
191 }
192 } else {
193 netdev->stats.tx_packets++;
194 netdev->stats.tx_bytes += skb->len;
195 }
196
197 dev_kfree_skb(skb);
198 spin_unlock(&kingsun->lock);
199
200 return ret;
201 }
202
203 /* Receive callback function */
kingsun_rcv_irq(struct urb * urb)204 static void kingsun_rcv_irq(struct urb *urb)
205 {
206 struct kingsun_cb *kingsun = urb->context;
207 int ret;
208
209 /* in process of stopping, just drop data */
210 if (!netif_running(kingsun->netdev)) {
211 kingsun->receiving = 0;
212 return;
213 }
214
215 /* unlink, shutdown, unplug, other nasties */
216 if (urb->status != 0) {
217 err("kingsun_rcv_irq: urb asynchronously failed - %d",
218 urb->status);
219 kingsun->receiving = 0;
220 return;
221 }
222
223 if (urb->actual_length == kingsun->max_rx) {
224 __u8 *bytes = urb->transfer_buffer;
225 int i;
226
227 /* The very first byte in the buffer indicates the length of
228 valid data in the read. This byte must be in the range
229 1..kingsun->max_rx -1 . Values outside this range indicate
230 an uninitialized Rx buffer when the dongle has just been
231 plugged in. */
232 if (bytes[0] >= 1 && bytes[0] < kingsun->max_rx) {
233 for (i = 1; i <= bytes[0]; i++) {
234 async_unwrap_char(kingsun->netdev,
235 &kingsun->netdev->stats,
236 &kingsun->rx_buff, bytes[i]);
237 }
238 do_gettimeofday(&kingsun->rx_time);
239 kingsun->receiving =
240 (kingsun->rx_buff.state != OUTSIDE_FRAME)
241 ? 1 : 0;
242 }
243 } else if (urb->actual_length > 0) {
244 err("%s(): Unexpected response length, expected %d got %d",
245 __func__, kingsun->max_rx, urb->actual_length);
246 }
247 /* This urb has already been filled in kingsun_net_open */
248 ret = usb_submit_urb(urb, GFP_ATOMIC);
249 }
250
251 /*
252 * Function kingsun_net_open (dev)
253 *
254 * Network device is taken up. Usually this is done by "ifconfig irda0 up"
255 */
kingsun_net_open(struct net_device * netdev)256 static int kingsun_net_open(struct net_device *netdev)
257 {
258 struct kingsun_cb *kingsun = netdev_priv(netdev);
259 int err = -ENOMEM;
260 char hwname[16];
261
262 /* At this point, urbs are NULL, and skb is NULL (see kingsun_probe) */
263 kingsun->receiving = 0;
264
265 /* Initialize for SIR to copy data directly into skb. */
266 kingsun->rx_buff.in_frame = FALSE;
267 kingsun->rx_buff.state = OUTSIDE_FRAME;
268 kingsun->rx_buff.truesize = IRDA_SKB_MAX_MTU;
269 kingsun->rx_buff.skb = dev_alloc_skb(IRDA_SKB_MAX_MTU);
270 if (!kingsun->rx_buff.skb)
271 goto free_mem;
272
273 skb_reserve(kingsun->rx_buff.skb, 1);
274 kingsun->rx_buff.head = kingsun->rx_buff.skb->data;
275 do_gettimeofday(&kingsun->rx_time);
276
277 kingsun->rx_urb = usb_alloc_urb(0, GFP_KERNEL);
278 if (!kingsun->rx_urb)
279 goto free_mem;
280
281 kingsun->tx_urb = usb_alloc_urb(0, GFP_KERNEL);
282 if (!kingsun->tx_urb)
283 goto free_mem;
284
285 /*
286 * Now that everything should be initialized properly,
287 * Open new IrLAP layer instance to take care of us...
288 */
289 sprintf(hwname, "usb#%d", kingsun->usbdev->devnum);
290 kingsun->irlap = irlap_open(netdev, &kingsun->qos, hwname);
291 if (!kingsun->irlap) {
292 err("kingsun-sir: irlap_open failed");
293 goto free_mem;
294 }
295
296 /* Start first reception */
297 usb_fill_int_urb(kingsun->rx_urb, kingsun->usbdev,
298 usb_rcvintpipe(kingsun->usbdev, kingsun->ep_in),
299 kingsun->in_buf, kingsun->max_rx,
300 kingsun_rcv_irq, kingsun, 1);
301 kingsun->rx_urb->status = 0;
302 err = usb_submit_urb(kingsun->rx_urb, GFP_KERNEL);
303 if (err) {
304 err("kingsun-sir: first urb-submit failed: %d", err);
305 goto close_irlap;
306 }
307
308 netif_start_queue(netdev);
309
310 /* Situation at this point:
311 - all work buffers allocated
312 - urbs allocated and ready to fill
313 - max rx packet known (in max_rx)
314 - unwrap state machine initialized, in state outside of any frame
315 - receive request in progress
316 - IrLAP layer started, about to hand over packets to send
317 */
318
319 return 0;
320
321 close_irlap:
322 irlap_close(kingsun->irlap);
323 free_mem:
324 if (kingsun->tx_urb) {
325 usb_free_urb(kingsun->tx_urb);
326 kingsun->tx_urb = NULL;
327 }
328 if (kingsun->rx_urb) {
329 usb_free_urb(kingsun->rx_urb);
330 kingsun->rx_urb = NULL;
331 }
332 if (kingsun->rx_buff.skb) {
333 kfree_skb(kingsun->rx_buff.skb);
334 kingsun->rx_buff.skb = NULL;
335 kingsun->rx_buff.head = NULL;
336 }
337 return err;
338 }
339
340 /*
341 * Function kingsun_net_close (kingsun)
342 *
343 * Network device is taken down. Usually this is done by
344 * "ifconfig irda0 down"
345 */
kingsun_net_close(struct net_device * netdev)346 static int kingsun_net_close(struct net_device *netdev)
347 {
348 struct kingsun_cb *kingsun = netdev_priv(netdev);
349
350 /* Stop transmit processing */
351 netif_stop_queue(netdev);
352
353 /* Mop up receive && transmit urb's */
354 usb_kill_urb(kingsun->tx_urb);
355 usb_kill_urb(kingsun->rx_urb);
356
357 usb_free_urb(kingsun->tx_urb);
358 usb_free_urb(kingsun->rx_urb);
359
360 kingsun->tx_urb = NULL;
361 kingsun->rx_urb = NULL;
362
363 kfree_skb(kingsun->rx_buff.skb);
364 kingsun->rx_buff.skb = NULL;
365 kingsun->rx_buff.head = NULL;
366 kingsun->rx_buff.in_frame = FALSE;
367 kingsun->rx_buff.state = OUTSIDE_FRAME;
368 kingsun->receiving = 0;
369
370 /* Stop and remove instance of IrLAP */
371 if (kingsun->irlap)
372 irlap_close(kingsun->irlap);
373
374 kingsun->irlap = NULL;
375
376 return 0;
377 }
378
379 /*
380 * IOCTLs : Extra out-of-band network commands...
381 */
kingsun_net_ioctl(struct net_device * netdev,struct ifreq * rq,int cmd)382 static int kingsun_net_ioctl(struct net_device *netdev, struct ifreq *rq,
383 int cmd)
384 {
385 struct if_irda_req *irq = (struct if_irda_req *) rq;
386 struct kingsun_cb *kingsun = netdev_priv(netdev);
387 int ret = 0;
388
389 switch (cmd) {
390 case SIOCSBANDWIDTH: /* Set bandwidth */
391 if (!capable(CAP_NET_ADMIN))
392 return -EPERM;
393
394 /* Check if the device is still there */
395 if (netif_device_present(kingsun->netdev))
396 /* No observed commands for speed change */
397 ret = -EOPNOTSUPP;
398 break;
399
400 case SIOCSMEDIABUSY: /* Set media busy */
401 if (!capable(CAP_NET_ADMIN))
402 return -EPERM;
403
404 /* Check if the IrDA stack is still there */
405 if (netif_running(kingsun->netdev))
406 irda_device_set_media_busy(kingsun->netdev, TRUE);
407 break;
408
409 case SIOCGRECEIVING:
410 /* Only approximately true */
411 irq->ifr_receiving = kingsun->receiving;
412 break;
413
414 default:
415 ret = -EOPNOTSUPP;
416 }
417
418 return ret;
419 }
420
421
422 /*
423 * This routine is called by the USB subsystem for each new device
424 * in the system. We need to check if the device is ours, and in
425 * this case start handling it.
426 */
kingsun_probe(struct usb_interface * intf,const struct usb_device_id * id)427 static int kingsun_probe(struct usb_interface *intf,
428 const struct usb_device_id *id)
429 {
430 struct usb_host_interface *interface;
431 struct usb_endpoint_descriptor *endpoint;
432
433 struct usb_device *dev = interface_to_usbdev(intf);
434 struct kingsun_cb *kingsun = NULL;
435 struct net_device *net = NULL;
436 int ret = -ENOMEM;
437 int pipe, maxp_in, maxp_out;
438 __u8 ep_in;
439 __u8 ep_out;
440
441 /* Check that there really are two interrupt endpoints.
442 Check based on the one in drivers/usb/input/usbmouse.c
443 */
444 interface = intf->cur_altsetting;
445 if (interface->desc.bNumEndpoints != 2) {
446 err("kingsun-sir: expected 2 endpoints, found %d",
447 interface->desc.bNumEndpoints);
448 return -ENODEV;
449 }
450 endpoint = &interface->endpoint[KINGSUN_EP_IN].desc;
451 if (!usb_endpoint_is_int_in(endpoint)) {
452 err("kingsun-sir: endpoint 0 is not interrupt IN");
453 return -ENODEV;
454 }
455
456 ep_in = endpoint->bEndpointAddress;
457 pipe = usb_rcvintpipe(dev, ep_in);
458 maxp_in = usb_maxpacket(dev, pipe, usb_pipeout(pipe));
459 if (maxp_in > 255 || maxp_in <= 1) {
460 err("%s: endpoint 0 has max packet size %d not in range",
461 __FILE__, maxp_in);
462 return -ENODEV;
463 }
464
465 endpoint = &interface->endpoint[KINGSUN_EP_OUT].desc;
466 if (!usb_endpoint_is_int_out(endpoint)) {
467 err("kingsun-sir: endpoint 1 is not interrupt OUT");
468 return -ENODEV;
469 }
470
471 ep_out = endpoint->bEndpointAddress;
472 pipe = usb_sndintpipe(dev, ep_out);
473 maxp_out = usb_maxpacket(dev, pipe, usb_pipeout(pipe));
474
475 /* Allocate network device container. */
476 net = alloc_irdadev(sizeof(*kingsun));
477 if(!net)
478 goto err_out1;
479
480 SET_NETDEV_DEV(net, &intf->dev);
481 kingsun = netdev_priv(net);
482 kingsun->irlap = NULL;
483 kingsun->tx_urb = NULL;
484 kingsun->rx_urb = NULL;
485 kingsun->ep_in = ep_in;
486 kingsun->ep_out = ep_out;
487 kingsun->in_buf = NULL;
488 kingsun->out_buf = NULL;
489 kingsun->max_rx = (__u8)maxp_in;
490 kingsun->max_tx = (__u8)maxp_out;
491 kingsun->netdev = net;
492 kingsun->usbdev = dev;
493 kingsun->rx_buff.in_frame = FALSE;
494 kingsun->rx_buff.state = OUTSIDE_FRAME;
495 kingsun->rx_buff.skb = NULL;
496 kingsun->receiving = 0;
497 spin_lock_init(&kingsun->lock);
498
499 /* Allocate input buffer */
500 kingsun->in_buf = kmalloc(kingsun->max_rx, GFP_KERNEL);
501 if (!kingsun->in_buf)
502 goto free_mem;
503
504 /* Allocate output buffer */
505 kingsun->out_buf = kmalloc(KINGSUN_FIFO_SIZE, GFP_KERNEL);
506 if (!kingsun->out_buf)
507 goto free_mem;
508
509 printk(KERN_INFO "KingSun/DonShine IRDA/USB found at address %d, "
510 "Vendor: %x, Product: %x\n",
511 dev->devnum, le16_to_cpu(dev->descriptor.idVendor),
512 le16_to_cpu(dev->descriptor.idProduct));
513
514 /* Initialize QoS for this device */
515 irda_init_max_qos_capabilies(&kingsun->qos);
516
517 /* That's the Rx capability. */
518 kingsun->qos.baud_rate.bits &= IR_9600;
519 kingsun->qos.min_turn_time.bits &= KINGSUN_MTT;
520 irda_qos_bits_to_value(&kingsun->qos);
521
522 /* Override the network functions we need to use */
523 net->hard_start_xmit = kingsun_hard_xmit;
524 net->open = kingsun_net_open;
525 net->stop = kingsun_net_close;
526 net->do_ioctl = kingsun_net_ioctl;
527
528 ret = register_netdev(net);
529 if (ret != 0)
530 goto free_mem;
531
532 dev_info(&net->dev, "IrDA: Registered KingSun/DonShine device %s\n",
533 net->name);
534
535 usb_set_intfdata(intf, kingsun);
536
537 /* Situation at this point:
538 - all work buffers allocated
539 - urbs not allocated, set to NULL
540 - max rx packet known (in max_rx)
541 - unwrap state machine (partially) initialized, but skb == NULL
542 */
543
544 return 0;
545
546 free_mem:
547 if (kingsun->out_buf) kfree(kingsun->out_buf);
548 if (kingsun->in_buf) kfree(kingsun->in_buf);
549 free_netdev(net);
550 err_out1:
551 return ret;
552 }
553
554 /*
555 * The current device is removed, the USB layer tell us to shut it down...
556 */
kingsun_disconnect(struct usb_interface * intf)557 static void kingsun_disconnect(struct usb_interface *intf)
558 {
559 struct kingsun_cb *kingsun = usb_get_intfdata(intf);
560
561 if (!kingsun)
562 return;
563
564 unregister_netdev(kingsun->netdev);
565
566 /* Mop up receive && transmit urb's */
567 if (kingsun->tx_urb != NULL) {
568 usb_kill_urb(kingsun->tx_urb);
569 usb_free_urb(kingsun->tx_urb);
570 kingsun->tx_urb = NULL;
571 }
572 if (kingsun->rx_urb != NULL) {
573 usb_kill_urb(kingsun->rx_urb);
574 usb_free_urb(kingsun->rx_urb);
575 kingsun->rx_urb = NULL;
576 }
577
578 kfree(kingsun->out_buf);
579 kfree(kingsun->in_buf);
580 free_netdev(kingsun->netdev);
581
582 usb_set_intfdata(intf, NULL);
583 }
584
585 #ifdef CONFIG_PM
586 /* USB suspend, so power off the transmitter/receiver */
kingsun_suspend(struct usb_interface * intf,pm_message_t message)587 static int kingsun_suspend(struct usb_interface *intf, pm_message_t message)
588 {
589 struct kingsun_cb *kingsun = usb_get_intfdata(intf);
590
591 netif_device_detach(kingsun->netdev);
592 if (kingsun->tx_urb != NULL) usb_kill_urb(kingsun->tx_urb);
593 if (kingsun->rx_urb != NULL) usb_kill_urb(kingsun->rx_urb);
594 return 0;
595 }
596
597 /* Coming out of suspend, so reset hardware */
kingsun_resume(struct usb_interface * intf)598 static int kingsun_resume(struct usb_interface *intf)
599 {
600 struct kingsun_cb *kingsun = usb_get_intfdata(intf);
601
602 if (kingsun->rx_urb != NULL)
603 usb_submit_urb(kingsun->rx_urb, GFP_KERNEL);
604 netif_device_attach(kingsun->netdev);
605
606 return 0;
607 }
608 #endif
609
610 /*
611 * USB device callbacks
612 */
613 static struct usb_driver irda_driver = {
614 .name = "kingsun-sir",
615 .probe = kingsun_probe,
616 .disconnect = kingsun_disconnect,
617 .id_table = dongles,
618 #ifdef CONFIG_PM
619 .suspend = kingsun_suspend,
620 .resume = kingsun_resume,
621 #endif
622 };
623
624 /*
625 * Module insertion
626 */
kingsun_init(void)627 static int __init kingsun_init(void)
628 {
629 return usb_register(&irda_driver);
630 }
631 module_init(kingsun_init);
632
633 /*
634 * Module removal
635 */
kingsun_cleanup(void)636 static void __exit kingsun_cleanup(void)
637 {
638 /* Deregister the driver and remove all pending instances */
639 usb_deregister(&irda_driver);
640 }
641 module_exit(kingsun_cleanup);
642
643 MODULE_AUTHOR("Alex Villacís Lasso <a_villacis@palosanto.com>");
644 MODULE_DESCRIPTION("IrDA-USB Dongle Driver for KingSun/DonShine");
645 MODULE_LICENSE("GPL");
646