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/slab.h>
68 #include <linux/usb.h>
69 #include <linux/device.h>
70 #include <linux/crc32.h>
71
72 #include <asm/unaligned.h>
73 #include <asm/byteorder.h>
74 #include <asm/uaccess.h>
75
76 #include <net/irda/irda.h>
77 #include <net/irda/wrapper.h>
78 #include <net/irda/crc.h>
79
80 /*
81 * According to lsusb, 0x07c0 is assigned to
82 * "Code Mercenaries Hard- und Software GmbH"
83 */
84 #define KING_VENDOR_ID 0x07c0
85 #define KING_PRODUCT_ID 0x4200
86
87 /* These are the currently known USB ids */
88 static struct usb_device_id dongles[] = {
89 /* KingSun Co,Ltd IrDA/USB Bridge */
90 { USB_DEVICE(KING_VENDOR_ID, KING_PRODUCT_ID) },
91 { }
92 };
93
94 MODULE_DEVICE_TABLE(usb, dongles);
95
96 #define KINGSUN_MTT 0x07
97
98 #define KINGSUN_FIFO_SIZE 4096
99 #define KINGSUN_EP_IN 0
100 #define KINGSUN_EP_OUT 1
101
102 struct kingsun_cb {
103 struct usb_device *usbdev; /* init: probe_irda */
104 struct net_device *netdev; /* network layer */
105 struct irlap_cb *irlap; /* The link layer we are binded to */
106
107 struct qos_info qos;
108
109 __u8 *in_buf; /* receive buffer */
110 __u8 *out_buf; /* transmit buffer */
111 __u8 max_rx; /* max. atomic read from dongle
112 (usually 8), also size of in_buf */
113 __u8 max_tx; /* max. atomic write to dongle
114 (usually 8) */
115
116 iobuff_t rx_buff; /* receive unwrap state machine */
117 spinlock_t lock;
118 int receiving;
119
120 __u8 ep_in;
121 __u8 ep_out;
122
123 struct urb *tx_urb;
124 struct urb *rx_urb;
125 };
126
127 /* Callback transmission routine */
kingsun_send_irq(struct urb * urb)128 static void kingsun_send_irq(struct urb *urb)
129 {
130 struct kingsun_cb *kingsun = urb->context;
131 struct net_device *netdev = kingsun->netdev;
132
133 /* in process of stopping, just drop data */
134 if (!netif_running(kingsun->netdev)) {
135 dev_err(&kingsun->usbdev->dev,
136 "kingsun_send_irq: Network not running!\n");
137 return;
138 }
139
140 /* unlink, shutdown, unplug, other nasties */
141 if (urb->status != 0) {
142 dev_err(&kingsun->usbdev->dev,
143 "kingsun_send_irq: urb asynchronously failed - %d\n",
144 urb->status);
145 }
146 netif_wake_queue(netdev);
147 }
148
149 /*
150 * Called from net/core when new frame is available.
151 */
kingsun_hard_xmit(struct sk_buff * skb,struct net_device * netdev)152 static netdev_tx_t kingsun_hard_xmit(struct sk_buff *skb,
153 struct net_device *netdev)
154 {
155 struct kingsun_cb *kingsun;
156 int wraplen;
157 int ret = 0;
158
159 netif_stop_queue(netdev);
160
161 /* the IRDA wrapping routines don't deal with non linear skb */
162 SKB_LINEAR_ASSERT(skb);
163
164 kingsun = netdev_priv(netdev);
165
166 spin_lock(&kingsun->lock);
167
168 /* Append data to the end of whatever data remains to be transmitted */
169 wraplen = async_wrap_skb(skb,
170 kingsun->out_buf,
171 KINGSUN_FIFO_SIZE);
172
173 /* Calculate how much data can be transmitted in this urb */
174 usb_fill_int_urb(kingsun->tx_urb, kingsun->usbdev,
175 usb_sndintpipe(kingsun->usbdev, kingsun->ep_out),
176 kingsun->out_buf, wraplen, kingsun_send_irq,
177 kingsun, 1);
178
179 if ((ret = usb_submit_urb(kingsun->tx_urb, GFP_ATOMIC))) {
180 dev_err(&kingsun->usbdev->dev,
181 "kingsun_hard_xmit: failed tx_urb submit: %d\n", ret);
182 switch (ret) {
183 case -ENODEV:
184 case -EPIPE:
185 break;
186 default:
187 netdev->stats.tx_errors++;
188 netif_start_queue(netdev);
189 }
190 } else {
191 netdev->stats.tx_packets++;
192 netdev->stats.tx_bytes += skb->len;
193 }
194
195 dev_kfree_skb(skb);
196 spin_unlock(&kingsun->lock);
197
198 return NETDEV_TX_OK;
199 }
200
201 /* Receive callback function */
kingsun_rcv_irq(struct urb * urb)202 static void kingsun_rcv_irq(struct urb *urb)
203 {
204 struct kingsun_cb *kingsun = urb->context;
205 int ret;
206
207 /* in process of stopping, just drop data */
208 if (!netif_running(kingsun->netdev)) {
209 kingsun->receiving = 0;
210 return;
211 }
212
213 /* unlink, shutdown, unplug, other nasties */
214 if (urb->status != 0) {
215 dev_err(&kingsun->usbdev->dev,
216 "kingsun_rcv_irq: urb asynchronously failed - %d\n",
217 urb->status);
218 kingsun->receiving = 0;
219 return;
220 }
221
222 if (urb->actual_length == kingsun->max_rx) {
223 __u8 *bytes = urb->transfer_buffer;
224 int i;
225
226 /* The very first byte in the buffer indicates the length of
227 valid data in the read. This byte must be in the range
228 1..kingsun->max_rx -1 . Values outside this range indicate
229 an uninitialized Rx buffer when the dongle has just been
230 plugged in. */
231 if (bytes[0] >= 1 && bytes[0] < kingsun->max_rx) {
232 for (i = 1; i <= bytes[0]; i++) {
233 async_unwrap_char(kingsun->netdev,
234 &kingsun->netdev->stats,
235 &kingsun->rx_buff, bytes[i]);
236 }
237 kingsun->receiving =
238 (kingsun->rx_buff.state != OUTSIDE_FRAME)
239 ? 1 : 0;
240 }
241 } else if (urb->actual_length > 0) {
242 dev_err(&kingsun->usbdev->dev,
243 "%s(): Unexpected response length, expected %d got %d\n",
244 __func__, kingsun->max_rx, urb->actual_length);
245 }
246 /* This urb has already been filled in kingsun_net_open */
247 ret = usb_submit_urb(urb, GFP_ATOMIC);
248 }
249
250 /*
251 * Function kingsun_net_open (dev)
252 *
253 * Network device is taken up. Usually this is done by "ifconfig irda0 up"
254 */
kingsun_net_open(struct net_device * netdev)255 static int kingsun_net_open(struct net_device *netdev)
256 {
257 struct kingsun_cb *kingsun = netdev_priv(netdev);
258 int err = -ENOMEM;
259 char hwname[16];
260
261 /* At this point, urbs are NULL, and skb is NULL (see kingsun_probe) */
262 kingsun->receiving = 0;
263
264 /* Initialize for SIR to copy data directly into skb. */
265 kingsun->rx_buff.in_frame = FALSE;
266 kingsun->rx_buff.state = OUTSIDE_FRAME;
267 kingsun->rx_buff.truesize = IRDA_SKB_MAX_MTU;
268 kingsun->rx_buff.skb = dev_alloc_skb(IRDA_SKB_MAX_MTU);
269 if (!kingsun->rx_buff.skb)
270 goto free_mem;
271
272 skb_reserve(kingsun->rx_buff.skb, 1);
273 kingsun->rx_buff.head = kingsun->rx_buff.skb->data;
274
275 kingsun->rx_urb = usb_alloc_urb(0, GFP_KERNEL);
276 if (!kingsun->rx_urb)
277 goto free_mem;
278
279 kingsun->tx_urb = usb_alloc_urb(0, GFP_KERNEL);
280 if (!kingsun->tx_urb)
281 goto free_mem;
282
283 /*
284 * Now that everything should be initialized properly,
285 * Open new IrLAP layer instance to take care of us...
286 */
287 sprintf(hwname, "usb#%d", kingsun->usbdev->devnum);
288 kingsun->irlap = irlap_open(netdev, &kingsun->qos, hwname);
289 if (!kingsun->irlap) {
290 dev_err(&kingsun->usbdev->dev, "irlap_open failed\n");
291 goto free_mem;
292 }
293
294 /* Start first reception */
295 usb_fill_int_urb(kingsun->rx_urb, kingsun->usbdev,
296 usb_rcvintpipe(kingsun->usbdev, kingsun->ep_in),
297 kingsun->in_buf, kingsun->max_rx,
298 kingsun_rcv_irq, kingsun, 1);
299 kingsun->rx_urb->status = 0;
300 err = usb_submit_urb(kingsun->rx_urb, GFP_KERNEL);
301 if (err) {
302 dev_err(&kingsun->usbdev->dev,
303 "first urb-submit failed: %d\n", err);
304 goto close_irlap;
305 }
306
307 netif_start_queue(netdev);
308
309 /* Situation at this point:
310 - all work buffers allocated
311 - urbs allocated and ready to fill
312 - max rx packet known (in max_rx)
313 - unwrap state machine initialized, in state outside of any frame
314 - receive request in progress
315 - IrLAP layer started, about to hand over packets to send
316 */
317
318 return 0;
319
320 close_irlap:
321 irlap_close(kingsun->irlap);
322 free_mem:
323 if (kingsun->tx_urb) {
324 usb_free_urb(kingsun->tx_urb);
325 kingsun->tx_urb = NULL;
326 }
327 if (kingsun->rx_urb) {
328 usb_free_urb(kingsun->rx_urb);
329 kingsun->rx_urb = NULL;
330 }
331 if (kingsun->rx_buff.skb) {
332 kfree_skb(kingsun->rx_buff.skb);
333 kingsun->rx_buff.skb = NULL;
334 kingsun->rx_buff.head = NULL;
335 }
336 return err;
337 }
338
339 /*
340 * Function kingsun_net_close (kingsun)
341 *
342 * Network device is taken down. Usually this is done by
343 * "ifconfig irda0 down"
344 */
kingsun_net_close(struct net_device * netdev)345 static int kingsun_net_close(struct net_device *netdev)
346 {
347 struct kingsun_cb *kingsun = netdev_priv(netdev);
348
349 /* Stop transmit processing */
350 netif_stop_queue(netdev);
351
352 /* Mop up receive && transmit urb's */
353 usb_kill_urb(kingsun->tx_urb);
354 usb_kill_urb(kingsun->rx_urb);
355
356 usb_free_urb(kingsun->tx_urb);
357 usb_free_urb(kingsun->rx_urb);
358
359 kingsun->tx_urb = NULL;
360 kingsun->rx_urb = NULL;
361
362 kfree_skb(kingsun->rx_buff.skb);
363 kingsun->rx_buff.skb = NULL;
364 kingsun->rx_buff.head = NULL;
365 kingsun->rx_buff.in_frame = FALSE;
366 kingsun->rx_buff.state = OUTSIDE_FRAME;
367 kingsun->receiving = 0;
368
369 /* Stop and remove instance of IrLAP */
370 if (kingsun->irlap)
371 irlap_close(kingsun->irlap);
372
373 kingsun->irlap = NULL;
374
375 return 0;
376 }
377
378 /*
379 * IOCTLs : Extra out-of-band network commands...
380 */
kingsun_net_ioctl(struct net_device * netdev,struct ifreq * rq,int cmd)381 static int kingsun_net_ioctl(struct net_device *netdev, struct ifreq *rq,
382 int cmd)
383 {
384 struct if_irda_req *irq = (struct if_irda_req *) rq;
385 struct kingsun_cb *kingsun = netdev_priv(netdev);
386 int ret = 0;
387
388 switch (cmd) {
389 case SIOCSBANDWIDTH: /* Set bandwidth */
390 if (!capable(CAP_NET_ADMIN))
391 return -EPERM;
392
393 /* Check if the device is still there */
394 if (netif_device_present(kingsun->netdev))
395 /* No observed commands for speed change */
396 ret = -EOPNOTSUPP;
397 break;
398
399 case SIOCSMEDIABUSY: /* Set media busy */
400 if (!capable(CAP_NET_ADMIN))
401 return -EPERM;
402
403 /* Check if the IrDA stack is still there */
404 if (netif_running(kingsun->netdev))
405 irda_device_set_media_busy(kingsun->netdev, TRUE);
406 break;
407
408 case SIOCGRECEIVING:
409 /* Only approximately true */
410 irq->ifr_receiving = kingsun->receiving;
411 break;
412
413 default:
414 ret = -EOPNOTSUPP;
415 }
416
417 return ret;
418 }
419
420 static const struct net_device_ops kingsun_ops = {
421 .ndo_start_xmit = kingsun_hard_xmit,
422 .ndo_open = kingsun_net_open,
423 .ndo_stop = kingsun_net_close,
424 .ndo_do_ioctl = kingsun_net_ioctl,
425 };
426
427 /*
428 * This routine is called by the USB subsystem for each new device
429 * in the system. We need to check if the device is ours, and in
430 * this case start handling it.
431 */
kingsun_probe(struct usb_interface * intf,const struct usb_device_id * id)432 static int kingsun_probe(struct usb_interface *intf,
433 const struct usb_device_id *id)
434 {
435 struct usb_host_interface *interface;
436 struct usb_endpoint_descriptor *endpoint;
437
438 struct usb_device *dev = interface_to_usbdev(intf);
439 struct kingsun_cb *kingsun = NULL;
440 struct net_device *net = NULL;
441 int ret = -ENOMEM;
442 int pipe, maxp_in, maxp_out;
443 __u8 ep_in;
444 __u8 ep_out;
445
446 /* Check that there really are two interrupt endpoints.
447 Check based on the one in drivers/usb/input/usbmouse.c
448 */
449 interface = intf->cur_altsetting;
450 if (interface->desc.bNumEndpoints != 2) {
451 dev_err(&intf->dev,
452 "kingsun-sir: expected 2 endpoints, found %d\n",
453 interface->desc.bNumEndpoints);
454 return -ENODEV;
455 }
456 endpoint = &interface->endpoint[KINGSUN_EP_IN].desc;
457 if (!usb_endpoint_is_int_in(endpoint)) {
458 dev_err(&intf->dev,
459 "kingsun-sir: endpoint 0 is not interrupt IN\n");
460 return -ENODEV;
461 }
462
463 ep_in = endpoint->bEndpointAddress;
464 pipe = usb_rcvintpipe(dev, ep_in);
465 maxp_in = usb_maxpacket(dev, pipe, usb_pipeout(pipe));
466 if (maxp_in > 255 || maxp_in <= 1) {
467 dev_err(&intf->dev,
468 "endpoint 0 has max packet size %d not in range\n",
469 maxp_in);
470 return -ENODEV;
471 }
472
473 endpoint = &interface->endpoint[KINGSUN_EP_OUT].desc;
474 if (!usb_endpoint_is_int_out(endpoint)) {
475 dev_err(&intf->dev,
476 "kingsun-sir: endpoint 1 is not interrupt OUT\n");
477 return -ENODEV;
478 }
479
480 ep_out = endpoint->bEndpointAddress;
481 pipe = usb_sndintpipe(dev, ep_out);
482 maxp_out = usb_maxpacket(dev, pipe, usb_pipeout(pipe));
483
484 /* Allocate network device container. */
485 net = alloc_irdadev(sizeof(*kingsun));
486 if(!net)
487 goto err_out1;
488
489 SET_NETDEV_DEV(net, &intf->dev);
490 kingsun = netdev_priv(net);
491 kingsun->irlap = NULL;
492 kingsun->tx_urb = NULL;
493 kingsun->rx_urb = NULL;
494 kingsun->ep_in = ep_in;
495 kingsun->ep_out = ep_out;
496 kingsun->in_buf = NULL;
497 kingsun->out_buf = NULL;
498 kingsun->max_rx = (__u8)maxp_in;
499 kingsun->max_tx = (__u8)maxp_out;
500 kingsun->netdev = net;
501 kingsun->usbdev = dev;
502 kingsun->rx_buff.in_frame = FALSE;
503 kingsun->rx_buff.state = OUTSIDE_FRAME;
504 kingsun->rx_buff.skb = NULL;
505 kingsun->receiving = 0;
506 spin_lock_init(&kingsun->lock);
507
508 /* Allocate input buffer */
509 kingsun->in_buf = kmalloc(kingsun->max_rx, GFP_KERNEL);
510 if (!kingsun->in_buf)
511 goto free_mem;
512
513 /* Allocate output buffer */
514 kingsun->out_buf = kmalloc(KINGSUN_FIFO_SIZE, GFP_KERNEL);
515 if (!kingsun->out_buf)
516 goto free_mem;
517
518 printk(KERN_INFO "KingSun/DonShine IRDA/USB found at address %d, "
519 "Vendor: %x, Product: %x\n",
520 dev->devnum, le16_to_cpu(dev->descriptor.idVendor),
521 le16_to_cpu(dev->descriptor.idProduct));
522
523 /* Initialize QoS for this device */
524 irda_init_max_qos_capabilies(&kingsun->qos);
525
526 /* That's the Rx capability. */
527 kingsun->qos.baud_rate.bits &= IR_9600;
528 kingsun->qos.min_turn_time.bits &= KINGSUN_MTT;
529 irda_qos_bits_to_value(&kingsun->qos);
530
531 /* Override the network functions we need to use */
532 net->netdev_ops = &kingsun_ops;
533
534 ret = register_netdev(net);
535 if (ret != 0)
536 goto free_mem;
537
538 dev_info(&net->dev, "IrDA: Registered KingSun/DonShine device %s\n",
539 net->name);
540
541 usb_set_intfdata(intf, kingsun);
542
543 /* Situation at this point:
544 - all work buffers allocated
545 - urbs not allocated, set to NULL
546 - max rx packet known (in max_rx)
547 - unwrap state machine (partially) initialized, but skb == NULL
548 */
549
550 return 0;
551
552 free_mem:
553 kfree(kingsun->out_buf);
554 kfree(kingsun->in_buf);
555 free_netdev(net);
556 err_out1:
557 return ret;
558 }
559
560 /*
561 * The current device is removed, the USB layer tell us to shut it down...
562 */
kingsun_disconnect(struct usb_interface * intf)563 static void kingsun_disconnect(struct usb_interface *intf)
564 {
565 struct kingsun_cb *kingsun = usb_get_intfdata(intf);
566
567 if (!kingsun)
568 return;
569
570 unregister_netdev(kingsun->netdev);
571
572 /* Mop up receive && transmit urb's */
573 if (kingsun->tx_urb != NULL) {
574 usb_kill_urb(kingsun->tx_urb);
575 usb_free_urb(kingsun->tx_urb);
576 kingsun->tx_urb = NULL;
577 }
578 if (kingsun->rx_urb != NULL) {
579 usb_kill_urb(kingsun->rx_urb);
580 usb_free_urb(kingsun->rx_urb);
581 kingsun->rx_urb = NULL;
582 }
583
584 kfree(kingsun->out_buf);
585 kfree(kingsun->in_buf);
586 free_netdev(kingsun->netdev);
587
588 usb_set_intfdata(intf, NULL);
589 }
590
591 #ifdef CONFIG_PM
592 /* USB suspend, so power off the transmitter/receiver */
kingsun_suspend(struct usb_interface * intf,pm_message_t message)593 static int kingsun_suspend(struct usb_interface *intf, pm_message_t message)
594 {
595 struct kingsun_cb *kingsun = usb_get_intfdata(intf);
596
597 netif_device_detach(kingsun->netdev);
598 if (kingsun->tx_urb != NULL) usb_kill_urb(kingsun->tx_urb);
599 if (kingsun->rx_urb != NULL) usb_kill_urb(kingsun->rx_urb);
600 return 0;
601 }
602
603 /* Coming out of suspend, so reset hardware */
kingsun_resume(struct usb_interface * intf)604 static int kingsun_resume(struct usb_interface *intf)
605 {
606 struct kingsun_cb *kingsun = usb_get_intfdata(intf);
607
608 if (kingsun->rx_urb != NULL)
609 usb_submit_urb(kingsun->rx_urb, GFP_KERNEL);
610 netif_device_attach(kingsun->netdev);
611
612 return 0;
613 }
614 #endif
615
616 /*
617 * USB device callbacks
618 */
619 static struct usb_driver irda_driver = {
620 .name = "kingsun-sir",
621 .probe = kingsun_probe,
622 .disconnect = kingsun_disconnect,
623 .id_table = dongles,
624 #ifdef CONFIG_PM
625 .suspend = kingsun_suspend,
626 .resume = kingsun_resume,
627 #endif
628 };
629
630 module_usb_driver(irda_driver);
631
632 MODULE_AUTHOR("Alex Villacís Lasso <a_villacis@palosanto.com>");
633 MODULE_DESCRIPTION("IrDA-USB Dongle Driver for KingSun/DonShine");
634 MODULE_LICENSE("GPL");
635