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/usb.h>
70 #include <linux/device.h>
71 #include <linux/crc32.h>
72
73 #include <asm/unaligned.h>
74 #include <asm/byteorder.h>
75 #include <asm/uaccess.h>
76
77 #include <net/irda/irda.h>
78 #include <net/irda/wrapper.h>
79 #include <net/irda/crc.h>
80
81 /*
82 * According to lsusb, 0x07c0 is assigned to
83 * "Code Mercenaries Hard- und Software GmbH"
84 */
85 #define KING_VENDOR_ID 0x07c0
86 #define KING_PRODUCT_ID 0x4200
87
88 /* These are the currently known USB ids */
89 static struct usb_device_id dongles[] = {
90 /* KingSun Co,Ltd IrDA/USB Bridge */
91 { USB_DEVICE(KING_VENDOR_ID, KING_PRODUCT_ID) },
92 { }
93 };
94
95 MODULE_DEVICE_TABLE(usb, dongles);
96
97 #define KINGSUN_MTT 0x07
98
99 #define KINGSUN_FIFO_SIZE 4096
100 #define KINGSUN_EP_IN 0
101 #define KINGSUN_EP_OUT 1
102
103 struct kingsun_cb {
104 struct usb_device *usbdev; /* init: probe_irda */
105 struct net_device *netdev; /* network layer */
106 struct irlap_cb *irlap; /* The link layer we are binded to */
107
108 struct qos_info qos;
109
110 __u8 *in_buf; /* receive buffer */
111 __u8 *out_buf; /* transmit buffer */
112 __u8 max_rx; /* max. atomic read from dongle
113 (usually 8), also size of in_buf */
114 __u8 max_tx; /* max. atomic write to dongle
115 (usually 8) */
116
117 iobuff_t rx_buff; /* receive unwrap state machine */
118 struct timeval rx_time;
119 spinlock_t lock;
120 int receiving;
121
122 __u8 ep_in;
123 __u8 ep_out;
124
125 struct urb *tx_urb;
126 struct urb *rx_urb;
127 };
128
129 /* Callback transmission routine */
kingsun_send_irq(struct urb * urb)130 static void kingsun_send_irq(struct urb *urb)
131 {
132 struct kingsun_cb *kingsun = urb->context;
133 struct net_device *netdev = kingsun->netdev;
134
135 /* in process of stopping, just drop data */
136 if (!netif_running(kingsun->netdev)) {
137 dev_err(&kingsun->usbdev->dev,
138 "kingsun_send_irq: Network not running!\n");
139 return;
140 }
141
142 /* unlink, shutdown, unplug, other nasties */
143 if (urb->status != 0) {
144 dev_err(&kingsun->usbdev->dev,
145 "kingsun_send_irq: urb asynchronously failed - %d\n",
146 urb->status);
147 }
148 netif_wake_queue(netdev);
149 }
150
151 /*
152 * Called from net/core when new frame is available.
153 */
kingsun_hard_xmit(struct sk_buff * skb,struct net_device * netdev)154 static netdev_tx_t kingsun_hard_xmit(struct sk_buff *skb,
155 struct net_device *netdev)
156 {
157 struct kingsun_cb *kingsun;
158 int wraplen;
159 int ret = 0;
160
161 netif_stop_queue(netdev);
162
163 /* the IRDA wrapping routines don't deal with non linear skb */
164 SKB_LINEAR_ASSERT(skb);
165
166 kingsun = netdev_priv(netdev);
167
168 spin_lock(&kingsun->lock);
169
170 /* Append data to the end of whatever data remains to be transmitted */
171 wraplen = async_wrap_skb(skb,
172 kingsun->out_buf,
173 KINGSUN_FIFO_SIZE);
174
175 /* Calculate how much data can be transmitted in this urb */
176 usb_fill_int_urb(kingsun->tx_urb, kingsun->usbdev,
177 usb_sndintpipe(kingsun->usbdev, kingsun->ep_out),
178 kingsun->out_buf, wraplen, kingsun_send_irq,
179 kingsun, 1);
180
181 if ((ret = usb_submit_urb(kingsun->tx_urb, GFP_ATOMIC))) {
182 dev_err(&kingsun->usbdev->dev,
183 "kingsun_hard_xmit: failed tx_urb submit: %d\n", 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 NETDEV_TX_OK;
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 dev_err(&kingsun->usbdev->dev,
218 "kingsun_rcv_irq: urb asynchronously failed - %d\n",
219 urb->status);
220 kingsun->receiving = 0;
221 return;
222 }
223
224 if (urb->actual_length == kingsun->max_rx) {
225 __u8 *bytes = urb->transfer_buffer;
226 int i;
227
228 /* The very first byte in the buffer indicates the length of
229 valid data in the read. This byte must be in the range
230 1..kingsun->max_rx -1 . Values outside this range indicate
231 an uninitialized Rx buffer when the dongle has just been
232 plugged in. */
233 if (bytes[0] >= 1 && bytes[0] < kingsun->max_rx) {
234 for (i = 1; i <= bytes[0]; i++) {
235 async_unwrap_char(kingsun->netdev,
236 &kingsun->netdev->stats,
237 &kingsun->rx_buff, bytes[i]);
238 }
239 do_gettimeofday(&kingsun->rx_time);
240 kingsun->receiving =
241 (kingsun->rx_buff.state != OUTSIDE_FRAME)
242 ? 1 : 0;
243 }
244 } else if (urb->actual_length > 0) {
245 dev_err(&kingsun->usbdev->dev,
246 "%s(): Unexpected response length, expected %d got %d\n",
247 __func__, kingsun->max_rx, urb->actual_length);
248 }
249 /* This urb has already been filled in kingsun_net_open */
250 ret = usb_submit_urb(urb, GFP_ATOMIC);
251 }
252
253 /*
254 * Function kingsun_net_open (dev)
255 *
256 * Network device is taken up. Usually this is done by "ifconfig irda0 up"
257 */
kingsun_net_open(struct net_device * netdev)258 static int kingsun_net_open(struct net_device *netdev)
259 {
260 struct kingsun_cb *kingsun = netdev_priv(netdev);
261 int err = -ENOMEM;
262 char hwname[16];
263
264 /* At this point, urbs are NULL, and skb is NULL (see kingsun_probe) */
265 kingsun->receiving = 0;
266
267 /* Initialize for SIR to copy data directly into skb. */
268 kingsun->rx_buff.in_frame = FALSE;
269 kingsun->rx_buff.state = OUTSIDE_FRAME;
270 kingsun->rx_buff.truesize = IRDA_SKB_MAX_MTU;
271 kingsun->rx_buff.skb = dev_alloc_skb(IRDA_SKB_MAX_MTU);
272 if (!kingsun->rx_buff.skb)
273 goto free_mem;
274
275 skb_reserve(kingsun->rx_buff.skb, 1);
276 kingsun->rx_buff.head = kingsun->rx_buff.skb->data;
277 do_gettimeofday(&kingsun->rx_time);
278
279 kingsun->rx_urb = usb_alloc_urb(0, GFP_KERNEL);
280 if (!kingsun->rx_urb)
281 goto free_mem;
282
283 kingsun->tx_urb = usb_alloc_urb(0, GFP_KERNEL);
284 if (!kingsun->tx_urb)
285 goto free_mem;
286
287 /*
288 * Now that everything should be initialized properly,
289 * Open new IrLAP layer instance to take care of us...
290 */
291 sprintf(hwname, "usb#%d", kingsun->usbdev->devnum);
292 kingsun->irlap = irlap_open(netdev, &kingsun->qos, hwname);
293 if (!kingsun->irlap) {
294 dev_err(&kingsun->usbdev->dev, "irlap_open failed\n");
295 goto free_mem;
296 }
297
298 /* Start first reception */
299 usb_fill_int_urb(kingsun->rx_urb, kingsun->usbdev,
300 usb_rcvintpipe(kingsun->usbdev, kingsun->ep_in),
301 kingsun->in_buf, kingsun->max_rx,
302 kingsun_rcv_irq, kingsun, 1);
303 kingsun->rx_urb->status = 0;
304 err = usb_submit_urb(kingsun->rx_urb, GFP_KERNEL);
305 if (err) {
306 dev_err(&kingsun->usbdev->dev,
307 "first urb-submit failed: %d\n", err);
308 goto close_irlap;
309 }
310
311 netif_start_queue(netdev);
312
313 /* Situation at this point:
314 - all work buffers allocated
315 - urbs allocated and ready to fill
316 - max rx packet known (in max_rx)
317 - unwrap state machine initialized, in state outside of any frame
318 - receive request in progress
319 - IrLAP layer started, about to hand over packets to send
320 */
321
322 return 0;
323
324 close_irlap:
325 irlap_close(kingsun->irlap);
326 free_mem:
327 if (kingsun->tx_urb) {
328 usb_free_urb(kingsun->tx_urb);
329 kingsun->tx_urb = NULL;
330 }
331 if (kingsun->rx_urb) {
332 usb_free_urb(kingsun->rx_urb);
333 kingsun->rx_urb = NULL;
334 }
335 if (kingsun->rx_buff.skb) {
336 kfree_skb(kingsun->rx_buff.skb);
337 kingsun->rx_buff.skb = NULL;
338 kingsun->rx_buff.head = NULL;
339 }
340 return err;
341 }
342
343 /*
344 * Function kingsun_net_close (kingsun)
345 *
346 * Network device is taken down. Usually this is done by
347 * "ifconfig irda0 down"
348 */
kingsun_net_close(struct net_device * netdev)349 static int kingsun_net_close(struct net_device *netdev)
350 {
351 struct kingsun_cb *kingsun = netdev_priv(netdev);
352
353 /* Stop transmit processing */
354 netif_stop_queue(netdev);
355
356 /* Mop up receive && transmit urb's */
357 usb_kill_urb(kingsun->tx_urb);
358 usb_kill_urb(kingsun->rx_urb);
359
360 usb_free_urb(kingsun->tx_urb);
361 usb_free_urb(kingsun->rx_urb);
362
363 kingsun->tx_urb = NULL;
364 kingsun->rx_urb = NULL;
365
366 kfree_skb(kingsun->rx_buff.skb);
367 kingsun->rx_buff.skb = NULL;
368 kingsun->rx_buff.head = NULL;
369 kingsun->rx_buff.in_frame = FALSE;
370 kingsun->rx_buff.state = OUTSIDE_FRAME;
371 kingsun->receiving = 0;
372
373 /* Stop and remove instance of IrLAP */
374 if (kingsun->irlap)
375 irlap_close(kingsun->irlap);
376
377 kingsun->irlap = NULL;
378
379 return 0;
380 }
381
382 /*
383 * IOCTLs : Extra out-of-band network commands...
384 */
kingsun_net_ioctl(struct net_device * netdev,struct ifreq * rq,int cmd)385 static int kingsun_net_ioctl(struct net_device *netdev, struct ifreq *rq,
386 int cmd)
387 {
388 struct if_irda_req *irq = (struct if_irda_req *) rq;
389 struct kingsun_cb *kingsun = netdev_priv(netdev);
390 int ret = 0;
391
392 switch (cmd) {
393 case SIOCSBANDWIDTH: /* Set bandwidth */
394 if (!capable(CAP_NET_ADMIN))
395 return -EPERM;
396
397 /* Check if the device is still there */
398 if (netif_device_present(kingsun->netdev))
399 /* No observed commands for speed change */
400 ret = -EOPNOTSUPP;
401 break;
402
403 case SIOCSMEDIABUSY: /* Set media busy */
404 if (!capable(CAP_NET_ADMIN))
405 return -EPERM;
406
407 /* Check if the IrDA stack is still there */
408 if (netif_running(kingsun->netdev))
409 irda_device_set_media_busy(kingsun->netdev, TRUE);
410 break;
411
412 case SIOCGRECEIVING:
413 /* Only approximately true */
414 irq->ifr_receiving = kingsun->receiving;
415 break;
416
417 default:
418 ret = -EOPNOTSUPP;
419 }
420
421 return ret;
422 }
423
424 static const struct net_device_ops kingsun_ops = {
425 .ndo_start_xmit = kingsun_hard_xmit,
426 .ndo_open = kingsun_net_open,
427 .ndo_stop = kingsun_net_close,
428 .ndo_do_ioctl = kingsun_net_ioctl,
429 };
430
431 /*
432 * This routine is called by the USB subsystem for each new device
433 * in the system. We need to check if the device is ours, and in
434 * this case start handling it.
435 */
kingsun_probe(struct usb_interface * intf,const struct usb_device_id * id)436 static int kingsun_probe(struct usb_interface *intf,
437 const struct usb_device_id *id)
438 {
439 struct usb_host_interface *interface;
440 struct usb_endpoint_descriptor *endpoint;
441
442 struct usb_device *dev = interface_to_usbdev(intf);
443 struct kingsun_cb *kingsun = NULL;
444 struct net_device *net = NULL;
445 int ret = -ENOMEM;
446 int pipe, maxp_in, maxp_out;
447 __u8 ep_in;
448 __u8 ep_out;
449
450 /* Check that there really are two interrupt endpoints.
451 Check based on the one in drivers/usb/input/usbmouse.c
452 */
453 interface = intf->cur_altsetting;
454 if (interface->desc.bNumEndpoints != 2) {
455 dev_err(&intf->dev,
456 "kingsun-sir: expected 2 endpoints, found %d\n",
457 interface->desc.bNumEndpoints);
458 return -ENODEV;
459 }
460 endpoint = &interface->endpoint[KINGSUN_EP_IN].desc;
461 if (!usb_endpoint_is_int_in(endpoint)) {
462 dev_err(&intf->dev,
463 "kingsun-sir: endpoint 0 is not interrupt IN\n");
464 return -ENODEV;
465 }
466
467 ep_in = endpoint->bEndpointAddress;
468 pipe = usb_rcvintpipe(dev, ep_in);
469 maxp_in = usb_maxpacket(dev, pipe, usb_pipeout(pipe));
470 if (maxp_in > 255 || maxp_in <= 1) {
471 dev_err(&intf->dev,
472 "endpoint 0 has max packet size %d not in range\n",
473 maxp_in);
474 return -ENODEV;
475 }
476
477 endpoint = &interface->endpoint[KINGSUN_EP_OUT].desc;
478 if (!usb_endpoint_is_int_out(endpoint)) {
479 dev_err(&intf->dev,
480 "kingsun-sir: endpoint 1 is not interrupt OUT\n");
481 return -ENODEV;
482 }
483
484 ep_out = endpoint->bEndpointAddress;
485 pipe = usb_sndintpipe(dev, ep_out);
486 maxp_out = usb_maxpacket(dev, pipe, usb_pipeout(pipe));
487
488 /* Allocate network device container. */
489 net = alloc_irdadev(sizeof(*kingsun));
490 if(!net)
491 goto err_out1;
492
493 SET_NETDEV_DEV(net, &intf->dev);
494 kingsun = netdev_priv(net);
495 kingsun->irlap = NULL;
496 kingsun->tx_urb = NULL;
497 kingsun->rx_urb = NULL;
498 kingsun->ep_in = ep_in;
499 kingsun->ep_out = ep_out;
500 kingsun->in_buf = NULL;
501 kingsun->out_buf = NULL;
502 kingsun->max_rx = (__u8)maxp_in;
503 kingsun->max_tx = (__u8)maxp_out;
504 kingsun->netdev = net;
505 kingsun->usbdev = dev;
506 kingsun->rx_buff.in_frame = FALSE;
507 kingsun->rx_buff.state = OUTSIDE_FRAME;
508 kingsun->rx_buff.skb = NULL;
509 kingsun->receiving = 0;
510 spin_lock_init(&kingsun->lock);
511
512 /* Allocate input buffer */
513 kingsun->in_buf = kmalloc(kingsun->max_rx, GFP_KERNEL);
514 if (!kingsun->in_buf)
515 goto free_mem;
516
517 /* Allocate output buffer */
518 kingsun->out_buf = kmalloc(KINGSUN_FIFO_SIZE, GFP_KERNEL);
519 if (!kingsun->out_buf)
520 goto free_mem;
521
522 printk(KERN_INFO "KingSun/DonShine IRDA/USB found at address %d, "
523 "Vendor: %x, Product: %x\n",
524 dev->devnum, le16_to_cpu(dev->descriptor.idVendor),
525 le16_to_cpu(dev->descriptor.idProduct));
526
527 /* Initialize QoS for this device */
528 irda_init_max_qos_capabilies(&kingsun->qos);
529
530 /* That's the Rx capability. */
531 kingsun->qos.baud_rate.bits &= IR_9600;
532 kingsun->qos.min_turn_time.bits &= KINGSUN_MTT;
533 irda_qos_bits_to_value(&kingsun->qos);
534
535 /* Override the network functions we need to use */
536 net->netdev_ops = &kingsun_ops;
537
538 ret = register_netdev(net);
539 if (ret != 0)
540 goto free_mem;
541
542 dev_info(&net->dev, "IrDA: Registered KingSun/DonShine device %s\n",
543 net->name);
544
545 usb_set_intfdata(intf, kingsun);
546
547 /* Situation at this point:
548 - all work buffers allocated
549 - urbs not allocated, set to NULL
550 - max rx packet known (in max_rx)
551 - unwrap state machine (partially) initialized, but skb == NULL
552 */
553
554 return 0;
555
556 free_mem:
557 if (kingsun->out_buf) kfree(kingsun->out_buf);
558 if (kingsun->in_buf) kfree(kingsun->in_buf);
559 free_netdev(net);
560 err_out1:
561 return ret;
562 }
563
564 /*
565 * The current device is removed, the USB layer tell us to shut it down...
566 */
kingsun_disconnect(struct usb_interface * intf)567 static void kingsun_disconnect(struct usb_interface *intf)
568 {
569 struct kingsun_cb *kingsun = usb_get_intfdata(intf);
570
571 if (!kingsun)
572 return;
573
574 unregister_netdev(kingsun->netdev);
575
576 /* Mop up receive && transmit urb's */
577 if (kingsun->tx_urb != NULL) {
578 usb_kill_urb(kingsun->tx_urb);
579 usb_free_urb(kingsun->tx_urb);
580 kingsun->tx_urb = NULL;
581 }
582 if (kingsun->rx_urb != NULL) {
583 usb_kill_urb(kingsun->rx_urb);
584 usb_free_urb(kingsun->rx_urb);
585 kingsun->rx_urb = NULL;
586 }
587
588 kfree(kingsun->out_buf);
589 kfree(kingsun->in_buf);
590 free_netdev(kingsun->netdev);
591
592 usb_set_intfdata(intf, NULL);
593 }
594
595 #ifdef CONFIG_PM
596 /* USB suspend, so power off the transmitter/receiver */
kingsun_suspend(struct usb_interface * intf,pm_message_t message)597 static int kingsun_suspend(struct usb_interface *intf, pm_message_t message)
598 {
599 struct kingsun_cb *kingsun = usb_get_intfdata(intf);
600
601 netif_device_detach(kingsun->netdev);
602 if (kingsun->tx_urb != NULL) usb_kill_urb(kingsun->tx_urb);
603 if (kingsun->rx_urb != NULL) usb_kill_urb(kingsun->rx_urb);
604 return 0;
605 }
606
607 /* Coming out of suspend, so reset hardware */
kingsun_resume(struct usb_interface * intf)608 static int kingsun_resume(struct usb_interface *intf)
609 {
610 struct kingsun_cb *kingsun = usb_get_intfdata(intf);
611
612 if (kingsun->rx_urb != NULL)
613 usb_submit_urb(kingsun->rx_urb, GFP_KERNEL);
614 netif_device_attach(kingsun->netdev);
615
616 return 0;
617 }
618 #endif
619
620 /*
621 * USB device callbacks
622 */
623 static struct usb_driver irda_driver = {
624 .name = "kingsun-sir",
625 .probe = kingsun_probe,
626 .disconnect = kingsun_disconnect,
627 .id_table = dongles,
628 #ifdef CONFIG_PM
629 .suspend = kingsun_suspend,
630 .resume = kingsun_resume,
631 #endif
632 };
633
634 module_usb_driver(irda_driver);
635
636 MODULE_AUTHOR("Alex Villacís Lasso <a_villacis@palosanto.com>");
637 MODULE_DESCRIPTION("IrDA-USB Dongle Driver for KingSun/DonShine");
638 MODULE_LICENSE("GPL");
639