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 struct timeval rx_time;
118 spinlock_t lock;
119 int receiving;
120
121 __u8 ep_in;
122 __u8 ep_out;
123
124 struct urb *tx_urb;
125 struct urb *rx_urb;
126 };
127
128 /* Callback transmission routine */
kingsun_send_irq(struct urb * urb)129 static void kingsun_send_irq(struct urb *urb)
130 {
131 struct kingsun_cb *kingsun = urb->context;
132 struct net_device *netdev = kingsun->netdev;
133
134 /* in process of stopping, just drop data */
135 if (!netif_running(kingsun->netdev)) {
136 dev_err(&kingsun->usbdev->dev,
137 "kingsun_send_irq: Network not running!\n");
138 return;
139 }
140
141 /* unlink, shutdown, unplug, other nasties */
142 if (urb->status != 0) {
143 dev_err(&kingsun->usbdev->dev,
144 "kingsun_send_irq: urb asynchronously failed - %d\n",
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 netdev_tx_t kingsun_hard_xmit(struct sk_buff *skb,
154 struct net_device *netdev)
155 {
156 struct kingsun_cb *kingsun;
157 int wraplen;
158 int ret = 0;
159
160 netif_stop_queue(netdev);
161
162 /* the IRDA wrapping routines don't deal with non linear skb */
163 SKB_LINEAR_ASSERT(skb);
164
165 kingsun = netdev_priv(netdev);
166
167 spin_lock(&kingsun->lock);
168
169 /* Append data to the end of whatever data remains to be transmitted */
170 wraplen = async_wrap_skb(skb,
171 kingsun->out_buf,
172 KINGSUN_FIFO_SIZE);
173
174 /* Calculate how much data can be transmitted in this urb */
175 usb_fill_int_urb(kingsun->tx_urb, kingsun->usbdev,
176 usb_sndintpipe(kingsun->usbdev, kingsun->ep_out),
177 kingsun->out_buf, wraplen, kingsun_send_irq,
178 kingsun, 1);
179
180 if ((ret = usb_submit_urb(kingsun->tx_urb, GFP_ATOMIC))) {
181 dev_err(&kingsun->usbdev->dev,
182 "kingsun_hard_xmit: failed tx_urb submit: %d\n", ret);
183 switch (ret) {
184 case -ENODEV:
185 case -EPIPE:
186 break;
187 default:
188 netdev->stats.tx_errors++;
189 netif_start_queue(netdev);
190 }
191 } else {
192 netdev->stats.tx_packets++;
193 netdev->stats.tx_bytes += skb->len;
194 }
195
196 dev_kfree_skb(skb);
197 spin_unlock(&kingsun->lock);
198
199 return NETDEV_TX_OK;
200 }
201
202 /* Receive callback function */
kingsun_rcv_irq(struct urb * urb)203 static void kingsun_rcv_irq(struct urb *urb)
204 {
205 struct kingsun_cb *kingsun = urb->context;
206 int ret;
207
208 /* in process of stopping, just drop data */
209 if (!netif_running(kingsun->netdev)) {
210 kingsun->receiving = 0;
211 return;
212 }
213
214 /* unlink, shutdown, unplug, other nasties */
215 if (urb->status != 0) {
216 dev_err(&kingsun->usbdev->dev,
217 "kingsun_rcv_irq: urb asynchronously failed - %d\n",
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 dev_err(&kingsun->usbdev->dev,
245 "%s(): Unexpected response length, expected %d got %d\n",
246 __func__, kingsun->max_rx, urb->actual_length);
247 }
248 /* This urb has already been filled in kingsun_net_open */
249 ret = usb_submit_urb(urb, GFP_ATOMIC);
250 }
251
252 /*
253 * Function kingsun_net_open (dev)
254 *
255 * Network device is taken up. Usually this is done by "ifconfig irda0 up"
256 */
kingsun_net_open(struct net_device * netdev)257 static int kingsun_net_open(struct net_device *netdev)
258 {
259 struct kingsun_cb *kingsun = netdev_priv(netdev);
260 int err = -ENOMEM;
261 char hwname[16];
262
263 /* At this point, urbs are NULL, and skb is NULL (see kingsun_probe) */
264 kingsun->receiving = 0;
265
266 /* Initialize for SIR to copy data directly into skb. */
267 kingsun->rx_buff.in_frame = FALSE;
268 kingsun->rx_buff.state = OUTSIDE_FRAME;
269 kingsun->rx_buff.truesize = IRDA_SKB_MAX_MTU;
270 kingsun->rx_buff.skb = dev_alloc_skb(IRDA_SKB_MAX_MTU);
271 if (!kingsun->rx_buff.skb)
272 goto free_mem;
273
274 skb_reserve(kingsun->rx_buff.skb, 1);
275 kingsun->rx_buff.head = kingsun->rx_buff.skb->data;
276 do_gettimeofday(&kingsun->rx_time);
277
278 kingsun->rx_urb = usb_alloc_urb(0, GFP_KERNEL);
279 if (!kingsun->rx_urb)
280 goto free_mem;
281
282 kingsun->tx_urb = usb_alloc_urb(0, GFP_KERNEL);
283 if (!kingsun->tx_urb)
284 goto free_mem;
285
286 /*
287 * Now that everything should be initialized properly,
288 * Open new IrLAP layer instance to take care of us...
289 */
290 sprintf(hwname, "usb#%d", kingsun->usbdev->devnum);
291 kingsun->irlap = irlap_open(netdev, &kingsun->qos, hwname);
292 if (!kingsun->irlap) {
293 dev_err(&kingsun->usbdev->dev, "irlap_open failed\n");
294 goto free_mem;
295 }
296
297 /* Start first reception */
298 usb_fill_int_urb(kingsun->rx_urb, kingsun->usbdev,
299 usb_rcvintpipe(kingsun->usbdev, kingsun->ep_in),
300 kingsun->in_buf, kingsun->max_rx,
301 kingsun_rcv_irq, kingsun, 1);
302 kingsun->rx_urb->status = 0;
303 err = usb_submit_urb(kingsun->rx_urb, GFP_KERNEL);
304 if (err) {
305 dev_err(&kingsun->usbdev->dev,
306 "first urb-submit failed: %d\n", err);
307 goto close_irlap;
308 }
309
310 netif_start_queue(netdev);
311
312 /* Situation at this point:
313 - all work buffers allocated
314 - urbs allocated and ready to fill
315 - max rx packet known (in max_rx)
316 - unwrap state machine initialized, in state outside of any frame
317 - receive request in progress
318 - IrLAP layer started, about to hand over packets to send
319 */
320
321 return 0;
322
323 close_irlap:
324 irlap_close(kingsun->irlap);
325 free_mem:
326 if (kingsun->tx_urb) {
327 usb_free_urb(kingsun->tx_urb);
328 kingsun->tx_urb = NULL;
329 }
330 if (kingsun->rx_urb) {
331 usb_free_urb(kingsun->rx_urb);
332 kingsun->rx_urb = NULL;
333 }
334 if (kingsun->rx_buff.skb) {
335 kfree_skb(kingsun->rx_buff.skb);
336 kingsun->rx_buff.skb = NULL;
337 kingsun->rx_buff.head = NULL;
338 }
339 return err;
340 }
341
342 /*
343 * Function kingsun_net_close (kingsun)
344 *
345 * Network device is taken down. Usually this is done by
346 * "ifconfig irda0 down"
347 */
kingsun_net_close(struct net_device * netdev)348 static int kingsun_net_close(struct net_device *netdev)
349 {
350 struct kingsun_cb *kingsun = netdev_priv(netdev);
351
352 /* Stop transmit processing */
353 netif_stop_queue(netdev);
354
355 /* Mop up receive && transmit urb's */
356 usb_kill_urb(kingsun->tx_urb);
357 usb_kill_urb(kingsun->rx_urb);
358
359 usb_free_urb(kingsun->tx_urb);
360 usb_free_urb(kingsun->rx_urb);
361
362 kingsun->tx_urb = NULL;
363 kingsun->rx_urb = NULL;
364
365 kfree_skb(kingsun->rx_buff.skb);
366 kingsun->rx_buff.skb = NULL;
367 kingsun->rx_buff.head = NULL;
368 kingsun->rx_buff.in_frame = FALSE;
369 kingsun->rx_buff.state = OUTSIDE_FRAME;
370 kingsun->receiving = 0;
371
372 /* Stop and remove instance of IrLAP */
373 if (kingsun->irlap)
374 irlap_close(kingsun->irlap);
375
376 kingsun->irlap = NULL;
377
378 return 0;
379 }
380
381 /*
382 * IOCTLs : Extra out-of-band network commands...
383 */
kingsun_net_ioctl(struct net_device * netdev,struct ifreq * rq,int cmd)384 static int kingsun_net_ioctl(struct net_device *netdev, struct ifreq *rq,
385 int cmd)
386 {
387 struct if_irda_req *irq = (struct if_irda_req *) rq;
388 struct kingsun_cb *kingsun = netdev_priv(netdev);
389 int ret = 0;
390
391 switch (cmd) {
392 case SIOCSBANDWIDTH: /* Set bandwidth */
393 if (!capable(CAP_NET_ADMIN))
394 return -EPERM;
395
396 /* Check if the device is still there */
397 if (netif_device_present(kingsun->netdev))
398 /* No observed commands for speed change */
399 ret = -EOPNOTSUPP;
400 break;
401
402 case SIOCSMEDIABUSY: /* Set media busy */
403 if (!capable(CAP_NET_ADMIN))
404 return -EPERM;
405
406 /* Check if the IrDA stack is still there */
407 if (netif_running(kingsun->netdev))
408 irda_device_set_media_busy(kingsun->netdev, TRUE);
409 break;
410
411 case SIOCGRECEIVING:
412 /* Only approximately true */
413 irq->ifr_receiving = kingsun->receiving;
414 break;
415
416 default:
417 ret = -EOPNOTSUPP;
418 }
419
420 return ret;
421 }
422
423 static const struct net_device_ops kingsun_ops = {
424 .ndo_start_xmit = kingsun_hard_xmit,
425 .ndo_open = kingsun_net_open,
426 .ndo_stop = kingsun_net_close,
427 .ndo_do_ioctl = kingsun_net_ioctl,
428 };
429
430 /*
431 * This routine is called by the USB subsystem for each new device
432 * in the system. We need to check if the device is ours, and in
433 * this case start handling it.
434 */
kingsun_probe(struct usb_interface * intf,const struct usb_device_id * id)435 static int kingsun_probe(struct usb_interface *intf,
436 const struct usb_device_id *id)
437 {
438 struct usb_host_interface *interface;
439 struct usb_endpoint_descriptor *endpoint;
440
441 struct usb_device *dev = interface_to_usbdev(intf);
442 struct kingsun_cb *kingsun = NULL;
443 struct net_device *net = NULL;
444 int ret = -ENOMEM;
445 int pipe, maxp_in, maxp_out;
446 __u8 ep_in;
447 __u8 ep_out;
448
449 /* Check that there really are two interrupt endpoints.
450 Check based on the one in drivers/usb/input/usbmouse.c
451 */
452 interface = intf->cur_altsetting;
453 if (interface->desc.bNumEndpoints != 2) {
454 dev_err(&intf->dev,
455 "kingsun-sir: expected 2 endpoints, found %d\n",
456 interface->desc.bNumEndpoints);
457 return -ENODEV;
458 }
459 endpoint = &interface->endpoint[KINGSUN_EP_IN].desc;
460 if (!usb_endpoint_is_int_in(endpoint)) {
461 dev_err(&intf->dev,
462 "kingsun-sir: endpoint 0 is not interrupt IN\n");
463 return -ENODEV;
464 }
465
466 ep_in = endpoint->bEndpointAddress;
467 pipe = usb_rcvintpipe(dev, ep_in);
468 maxp_in = usb_maxpacket(dev, pipe, usb_pipeout(pipe));
469 if (maxp_in > 255 || maxp_in <= 1) {
470 dev_err(&intf->dev,
471 "endpoint 0 has max packet size %d not in range\n",
472 maxp_in);
473 return -ENODEV;
474 }
475
476 endpoint = &interface->endpoint[KINGSUN_EP_OUT].desc;
477 if (!usb_endpoint_is_int_out(endpoint)) {
478 dev_err(&intf->dev,
479 "kingsun-sir: endpoint 1 is not interrupt OUT\n");
480 return -ENODEV;
481 }
482
483 ep_out = endpoint->bEndpointAddress;
484 pipe = usb_sndintpipe(dev, ep_out);
485 maxp_out = usb_maxpacket(dev, pipe, usb_pipeout(pipe));
486
487 /* Allocate network device container. */
488 net = alloc_irdadev(sizeof(*kingsun));
489 if(!net)
490 goto err_out1;
491
492 SET_NETDEV_DEV(net, &intf->dev);
493 kingsun = netdev_priv(net);
494 kingsun->irlap = NULL;
495 kingsun->tx_urb = NULL;
496 kingsun->rx_urb = NULL;
497 kingsun->ep_in = ep_in;
498 kingsun->ep_out = ep_out;
499 kingsun->in_buf = NULL;
500 kingsun->out_buf = NULL;
501 kingsun->max_rx = (__u8)maxp_in;
502 kingsun->max_tx = (__u8)maxp_out;
503 kingsun->netdev = net;
504 kingsun->usbdev = dev;
505 kingsun->rx_buff.in_frame = FALSE;
506 kingsun->rx_buff.state = OUTSIDE_FRAME;
507 kingsun->rx_buff.skb = NULL;
508 kingsun->receiving = 0;
509 spin_lock_init(&kingsun->lock);
510
511 /* Allocate input buffer */
512 kingsun->in_buf = kmalloc(kingsun->max_rx, GFP_KERNEL);
513 if (!kingsun->in_buf)
514 goto free_mem;
515
516 /* Allocate output buffer */
517 kingsun->out_buf = kmalloc(KINGSUN_FIFO_SIZE, GFP_KERNEL);
518 if (!kingsun->out_buf)
519 goto free_mem;
520
521 printk(KERN_INFO "KingSun/DonShine IRDA/USB found at address %d, "
522 "Vendor: %x, Product: %x\n",
523 dev->devnum, le16_to_cpu(dev->descriptor.idVendor),
524 le16_to_cpu(dev->descriptor.idProduct));
525
526 /* Initialize QoS for this device */
527 irda_init_max_qos_capabilies(&kingsun->qos);
528
529 /* That's the Rx capability. */
530 kingsun->qos.baud_rate.bits &= IR_9600;
531 kingsun->qos.min_turn_time.bits &= KINGSUN_MTT;
532 irda_qos_bits_to_value(&kingsun->qos);
533
534 /* Override the network functions we need to use */
535 net->netdev_ops = &kingsun_ops;
536
537 ret = register_netdev(net);
538 if (ret != 0)
539 goto free_mem;
540
541 dev_info(&net->dev, "IrDA: Registered KingSun/DonShine device %s\n",
542 net->name);
543
544 usb_set_intfdata(intf, kingsun);
545
546 /* Situation at this point:
547 - all work buffers allocated
548 - urbs not allocated, set to NULL
549 - max rx packet known (in max_rx)
550 - unwrap state machine (partially) initialized, but skb == NULL
551 */
552
553 return 0;
554
555 free_mem:
556 kfree(kingsun->out_buf);
557 kfree(kingsun->in_buf);
558 free_netdev(net);
559 err_out1:
560 return ret;
561 }
562
563 /*
564 * The current device is removed, the USB layer tell us to shut it down...
565 */
kingsun_disconnect(struct usb_interface * intf)566 static void kingsun_disconnect(struct usb_interface *intf)
567 {
568 struct kingsun_cb *kingsun = usb_get_intfdata(intf);
569
570 if (!kingsun)
571 return;
572
573 unregister_netdev(kingsun->netdev);
574
575 /* Mop up receive && transmit urb's */
576 if (kingsun->tx_urb != NULL) {
577 usb_kill_urb(kingsun->tx_urb);
578 usb_free_urb(kingsun->tx_urb);
579 kingsun->tx_urb = NULL;
580 }
581 if (kingsun->rx_urb != NULL) {
582 usb_kill_urb(kingsun->rx_urb);
583 usb_free_urb(kingsun->rx_urb);
584 kingsun->rx_urb = NULL;
585 }
586
587 kfree(kingsun->out_buf);
588 kfree(kingsun->in_buf);
589 free_netdev(kingsun->netdev);
590
591 usb_set_intfdata(intf, NULL);
592 }
593
594 #ifdef CONFIG_PM
595 /* USB suspend, so power off the transmitter/receiver */
kingsun_suspend(struct usb_interface * intf,pm_message_t message)596 static int kingsun_suspend(struct usb_interface *intf, pm_message_t message)
597 {
598 struct kingsun_cb *kingsun = usb_get_intfdata(intf);
599
600 netif_device_detach(kingsun->netdev);
601 if (kingsun->tx_urb != NULL) usb_kill_urb(kingsun->tx_urb);
602 if (kingsun->rx_urb != NULL) usb_kill_urb(kingsun->rx_urb);
603 return 0;
604 }
605
606 /* Coming out of suspend, so reset hardware */
kingsun_resume(struct usb_interface * intf)607 static int kingsun_resume(struct usb_interface *intf)
608 {
609 struct kingsun_cb *kingsun = usb_get_intfdata(intf);
610
611 if (kingsun->rx_urb != NULL)
612 usb_submit_urb(kingsun->rx_urb, GFP_KERNEL);
613 netif_device_attach(kingsun->netdev);
614
615 return 0;
616 }
617 #endif
618
619 /*
620 * USB device callbacks
621 */
622 static struct usb_driver irda_driver = {
623 .name = "kingsun-sir",
624 .probe = kingsun_probe,
625 .disconnect = kingsun_disconnect,
626 .id_table = dongles,
627 #ifdef CONFIG_PM
628 .suspend = kingsun_suspend,
629 .resume = kingsun_resume,
630 #endif
631 };
632
633 module_usb_driver(irda_driver);
634
635 MODULE_AUTHOR("Alex Villacís Lasso <a_villacis@palosanto.com>");
636 MODULE_DESCRIPTION("IrDA-USB Dongle Driver for KingSun/DonShine");
637 MODULE_LICENSE("GPL");
638