Merge branch 'upstream-2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarz...
[linux-2.6] / drivers / bluetooth / btuart_cs.c
1 /*
2  *
3  *  Driver for Bluetooth PCMCIA cards with HCI UART interface
4  *
5  *  Copyright (C) 2001-2002  Marcel Holtmann <marcel@holtmann.org>
6  *
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License version 2 as
10  *  published by the Free Software Foundation;
11  *
12  *  Software distributed under the License is distributed on an "AS
13  *  IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
14  *  implied. See the License for the specific language governing
15  *  rights and limitations under the License.
16  *
17  *  The initial developer of the original code is David A. Hinds
18  *  <dahinds@users.sourceforge.net>.  Portions created by David A. Hinds
19  *  are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
20  *
21  */
22
23 #include <linux/module.h>
24
25 #include <linux/kernel.h>
26 #include <linux/init.h>
27 #include <linux/slab.h>
28 #include <linux/types.h>
29 #include <linux/delay.h>
30 #include <linux/errno.h>
31 #include <linux/ptrace.h>
32 #include <linux/ioport.h>
33 #include <linux/spinlock.h>
34 #include <linux/moduleparam.h>
35
36 #include <linux/skbuff.h>
37 #include <linux/string.h>
38 #include <linux/serial.h>
39 #include <linux/serial_reg.h>
40 #include <linux/bitops.h>
41 #include <asm/system.h>
42 #include <asm/io.h>
43
44 #include <pcmcia/cs_types.h>
45 #include <pcmcia/cs.h>
46 #include <pcmcia/cistpl.h>
47 #include <pcmcia/ciscode.h>
48 #include <pcmcia/ds.h>
49 #include <pcmcia/cisreg.h>
50
51 #include <net/bluetooth/bluetooth.h>
52 #include <net/bluetooth/hci_core.h>
53
54
55
56 /* ======================== Module parameters ======================== */
57
58
59 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
60 MODULE_DESCRIPTION("Bluetooth driver for Bluetooth PCMCIA cards with HCI UART interface");
61 MODULE_LICENSE("GPL");
62
63
64
65 /* ======================== Local structures ======================== */
66
67
68 typedef struct btuart_info_t {
69         struct pcmcia_device *p_dev;
70         dev_node_t node;
71
72         struct hci_dev *hdev;
73
74         spinlock_t lock;        /* For serializing operations */
75
76         struct sk_buff_head txq;
77         unsigned long tx_state;
78
79         unsigned long rx_state;
80         unsigned long rx_count;
81         struct sk_buff *rx_skb;
82 } btuart_info_t;
83
84
85 static int btuart_config(struct pcmcia_device *link);
86 static void btuart_release(struct pcmcia_device *link);
87
88 static void btuart_detach(struct pcmcia_device *p_dev);
89
90
91 /* Maximum baud rate */
92 #define SPEED_MAX  115200
93
94 /* Default baud rate: 57600, 115200, 230400 or 460800 */
95 #define DEFAULT_BAUD_RATE  115200
96
97
98 /* Transmit states  */
99 #define XMIT_SENDING    1
100 #define XMIT_WAKEUP     2
101 #define XMIT_WAITING    8
102
103 /* Receiver states */
104 #define RECV_WAIT_PACKET_TYPE   0
105 #define RECV_WAIT_EVENT_HEADER  1
106 #define RECV_WAIT_ACL_HEADER    2
107 #define RECV_WAIT_SCO_HEADER    3
108 #define RECV_WAIT_DATA          4
109
110
111
112 /* ======================== Interrupt handling ======================== */
113
114
115 static int btuart_write(unsigned int iobase, int fifo_size, __u8 *buf, int len)
116 {
117         int actual = 0;
118
119         /* Tx FIFO should be empty */
120         if (!(inb(iobase + UART_LSR) & UART_LSR_THRE))
121                 return 0;
122
123         /* Fill FIFO with current frame */
124         while ((fifo_size-- > 0) && (actual < len)) {
125                 /* Transmit next byte */
126                 outb(buf[actual], iobase + UART_TX);
127                 actual++;
128         }
129
130         return actual;
131 }
132
133
134 static void btuart_write_wakeup(btuart_info_t *info)
135 {
136         if (!info) {
137                 BT_ERR("Unknown device");
138                 return;
139         }
140
141         if (test_and_set_bit(XMIT_SENDING, &(info->tx_state))) {
142                 set_bit(XMIT_WAKEUP, &(info->tx_state));
143                 return;
144         }
145
146         do {
147                 register unsigned int iobase = info->p_dev->io.BasePort1;
148                 register struct sk_buff *skb;
149                 register int len;
150
151                 clear_bit(XMIT_WAKEUP, &(info->tx_state));
152
153                 if (!pcmcia_dev_present(info->p_dev))
154                         return;
155
156                 if (!(skb = skb_dequeue(&(info->txq))))
157                         break;
158
159                 /* Send frame */
160                 len = btuart_write(iobase, 16, skb->data, skb->len);
161                 set_bit(XMIT_WAKEUP, &(info->tx_state));
162
163                 if (len == skb->len) {
164                         kfree_skb(skb);
165                 } else {
166                         skb_pull(skb, len);
167                         skb_queue_head(&(info->txq), skb);
168                 }
169
170                 info->hdev->stat.byte_tx += len;
171
172         } while (test_bit(XMIT_WAKEUP, &(info->tx_state)));
173
174         clear_bit(XMIT_SENDING, &(info->tx_state));
175 }
176
177
178 static void btuart_receive(btuart_info_t *info)
179 {
180         unsigned int iobase;
181         int boguscount = 0;
182
183         if (!info) {
184                 BT_ERR("Unknown device");
185                 return;
186         }
187
188         iobase = info->p_dev->io.BasePort1;
189
190         do {
191                 info->hdev->stat.byte_rx++;
192
193                 /* Allocate packet */
194                 if (info->rx_skb == NULL) {
195                         info->rx_state = RECV_WAIT_PACKET_TYPE;
196                         info->rx_count = 0;
197                         if (!(info->rx_skb = bt_skb_alloc(HCI_MAX_FRAME_SIZE, GFP_ATOMIC))) {
198                                 BT_ERR("Can't allocate mem for new packet");
199                                 return;
200                         }
201                 }
202
203                 if (info->rx_state == RECV_WAIT_PACKET_TYPE) {
204
205                         info->rx_skb->dev = (void *) info->hdev;
206                         bt_cb(info->rx_skb)->pkt_type = inb(iobase + UART_RX);
207
208                         switch (bt_cb(info->rx_skb)->pkt_type) {
209
210                         case HCI_EVENT_PKT:
211                                 info->rx_state = RECV_WAIT_EVENT_HEADER;
212                                 info->rx_count = HCI_EVENT_HDR_SIZE;
213                                 break;
214
215                         case HCI_ACLDATA_PKT:
216                                 info->rx_state = RECV_WAIT_ACL_HEADER;
217                                 info->rx_count = HCI_ACL_HDR_SIZE;
218                                 break;
219
220                         case HCI_SCODATA_PKT:
221                                 info->rx_state = RECV_WAIT_SCO_HEADER;
222                                 info->rx_count = HCI_SCO_HDR_SIZE;
223                                 break;
224
225                         default:
226                                 /* Unknown packet */
227                                 BT_ERR("Unknown HCI packet with type 0x%02x received", bt_cb(info->rx_skb)->pkt_type);
228                                 info->hdev->stat.err_rx++;
229                                 clear_bit(HCI_RUNNING, &(info->hdev->flags));
230
231                                 kfree_skb(info->rx_skb);
232                                 info->rx_skb = NULL;
233                                 break;
234
235                         }
236
237                 } else {
238
239                         *skb_put(info->rx_skb, 1) = inb(iobase + UART_RX);
240                         info->rx_count--;
241
242                         if (info->rx_count == 0) {
243
244                                 int dlen;
245                                 struct hci_event_hdr *eh;
246                                 struct hci_acl_hdr *ah;
247                                 struct hci_sco_hdr *sh;
248
249
250                                 switch (info->rx_state) {
251
252                                 case RECV_WAIT_EVENT_HEADER:
253                                         eh = hci_event_hdr(info->rx_skb);
254                                         info->rx_state = RECV_WAIT_DATA;
255                                         info->rx_count = eh->plen;
256                                         break;
257
258                                 case RECV_WAIT_ACL_HEADER:
259                                         ah = hci_acl_hdr(info->rx_skb);
260                                         dlen = __le16_to_cpu(ah->dlen);
261                                         info->rx_state = RECV_WAIT_DATA;
262                                         info->rx_count = dlen;
263                                         break;
264
265                                 case RECV_WAIT_SCO_HEADER:
266                                         sh = hci_sco_hdr(info->rx_skb);
267                                         info->rx_state = RECV_WAIT_DATA;
268                                         info->rx_count = sh->dlen;
269                                         break;
270
271                                 case RECV_WAIT_DATA:
272                                         hci_recv_frame(info->rx_skb);
273                                         info->rx_skb = NULL;
274                                         break;
275
276                                 }
277
278                         }
279
280                 }
281
282                 /* Make sure we don't stay here too long */
283                 if (boguscount++ > 16)
284                         break;
285
286         } while (inb(iobase + UART_LSR) & UART_LSR_DR);
287 }
288
289
290 static irqreturn_t btuart_interrupt(int irq, void *dev_inst)
291 {
292         btuart_info_t *info = dev_inst;
293         unsigned int iobase;
294         int boguscount = 0;
295         int iir, lsr;
296
297         BUG_ON(!info->hdev);
298
299         iobase = info->p_dev->io.BasePort1;
300
301         spin_lock(&(info->lock));
302
303         iir = inb(iobase + UART_IIR) & UART_IIR_ID;
304         while (iir) {
305
306                 /* Clear interrupt */
307                 lsr = inb(iobase + UART_LSR);
308
309                 switch (iir) {
310                 case UART_IIR_RLSI:
311                         BT_ERR("RLSI");
312                         break;
313                 case UART_IIR_RDI:
314                         /* Receive interrupt */
315                         btuart_receive(info);
316                         break;
317                 case UART_IIR_THRI:
318                         if (lsr & UART_LSR_THRE) {
319                                 /* Transmitter ready for data */
320                                 btuart_write_wakeup(info);
321                         }
322                         break;
323                 default:
324                         BT_ERR("Unhandled IIR=%#x", iir);
325                         break;
326                 }
327
328                 /* Make sure we don't stay here too long */
329                 if (boguscount++ > 100)
330                         break;
331
332                 iir = inb(iobase + UART_IIR) & UART_IIR_ID;
333
334         }
335
336         spin_unlock(&(info->lock));
337
338         return IRQ_HANDLED;
339 }
340
341
342 static void btuart_change_speed(btuart_info_t *info, unsigned int speed)
343 {
344         unsigned long flags;
345         unsigned int iobase;
346         int fcr;                /* FIFO control reg */
347         int lcr;                /* Line control reg */
348         int divisor;
349
350         if (!info) {
351                 BT_ERR("Unknown device");
352                 return;
353         }
354
355         iobase = info->p_dev->io.BasePort1;
356
357         spin_lock_irqsave(&(info->lock), flags);
358
359         /* Turn off interrupts */
360         outb(0, iobase + UART_IER);
361
362         divisor = SPEED_MAX / speed;
363
364         fcr = UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT;
365
366         /* 
367          * Use trigger level 1 to avoid 3 ms. timeout delay at 9600 bps, and
368          * almost 1,7 ms at 19200 bps. At speeds above that we can just forget
369          * about this timeout since it will always be fast enough. 
370          */
371
372         if (speed < 38400)
373                 fcr |= UART_FCR_TRIGGER_1;
374         else
375                 fcr |= UART_FCR_TRIGGER_14;
376
377         /* Bluetooth cards use 8N1 */
378         lcr = UART_LCR_WLEN8;
379
380         outb(UART_LCR_DLAB | lcr, iobase + UART_LCR);   /* Set DLAB */
381         outb(divisor & 0xff, iobase + UART_DLL);        /* Set speed */
382         outb(divisor >> 8, iobase + UART_DLM);
383         outb(lcr, iobase + UART_LCR);   /* Set 8N1  */
384         outb(fcr, iobase + UART_FCR);   /* Enable FIFO's */
385
386         /* Turn on interrupts */
387         outb(UART_IER_RLSI | UART_IER_RDI | UART_IER_THRI, iobase + UART_IER);
388
389         spin_unlock_irqrestore(&(info->lock), flags);
390 }
391
392
393
394 /* ======================== HCI interface ======================== */
395
396
397 static int btuart_hci_flush(struct hci_dev *hdev)
398 {
399         btuart_info_t *info = (btuart_info_t *)(hdev->driver_data);
400
401         /* Drop TX queue */
402         skb_queue_purge(&(info->txq));
403
404         return 0;
405 }
406
407
408 static int btuart_hci_open(struct hci_dev *hdev)
409 {
410         set_bit(HCI_RUNNING, &(hdev->flags));
411
412         return 0;
413 }
414
415
416 static int btuart_hci_close(struct hci_dev *hdev)
417 {
418         if (!test_and_clear_bit(HCI_RUNNING, &(hdev->flags)))
419                 return 0;
420
421         btuart_hci_flush(hdev);
422
423         return 0;
424 }
425
426
427 static int btuart_hci_send_frame(struct sk_buff *skb)
428 {
429         btuart_info_t *info;
430         struct hci_dev *hdev = (struct hci_dev *)(skb->dev);
431
432         if (!hdev) {
433                 BT_ERR("Frame for unknown HCI device (hdev=NULL)");
434                 return -ENODEV;
435         }
436
437         info = (btuart_info_t *)(hdev->driver_data);
438
439         switch (bt_cb(skb)->pkt_type) {
440         case HCI_COMMAND_PKT:
441                 hdev->stat.cmd_tx++;
442                 break;
443         case HCI_ACLDATA_PKT:
444                 hdev->stat.acl_tx++;
445                 break;
446         case HCI_SCODATA_PKT:
447                 hdev->stat.sco_tx++;
448                 break;
449         };
450
451         /* Prepend skb with frame type */
452         memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
453         skb_queue_tail(&(info->txq), skb);
454
455         btuart_write_wakeup(info);
456
457         return 0;
458 }
459
460
461 static void btuart_hci_destruct(struct hci_dev *hdev)
462 {
463 }
464
465
466 static int btuart_hci_ioctl(struct hci_dev *hdev, unsigned int cmd, unsigned long arg)
467 {
468         return -ENOIOCTLCMD;
469 }
470
471
472
473 /* ======================== Card services HCI interaction ======================== */
474
475
476 static int btuart_open(btuart_info_t *info)
477 {
478         unsigned long flags;
479         unsigned int iobase = info->p_dev->io.BasePort1;
480         struct hci_dev *hdev;
481
482         spin_lock_init(&(info->lock));
483
484         skb_queue_head_init(&(info->txq));
485
486         info->rx_state = RECV_WAIT_PACKET_TYPE;
487         info->rx_count = 0;
488         info->rx_skb = NULL;
489
490         /* Initialize HCI device */
491         hdev = hci_alloc_dev();
492         if (!hdev) {
493                 BT_ERR("Can't allocate HCI device");
494                 return -ENOMEM;
495         }
496
497         info->hdev = hdev;
498
499         hdev->type = HCI_PCCARD;
500         hdev->driver_data = info;
501         SET_HCIDEV_DEV(hdev, &info->p_dev->dev);
502
503         hdev->open     = btuart_hci_open;
504         hdev->close    = btuart_hci_close;
505         hdev->flush    = btuart_hci_flush;
506         hdev->send     = btuart_hci_send_frame;
507         hdev->destruct = btuart_hci_destruct;
508         hdev->ioctl    = btuart_hci_ioctl;
509
510         hdev->owner = THIS_MODULE;
511
512         spin_lock_irqsave(&(info->lock), flags);
513
514         /* Reset UART */
515         outb(0, iobase + UART_MCR);
516
517         /* Turn off interrupts */
518         outb(0, iobase + UART_IER);
519
520         /* Initialize UART */
521         outb(UART_LCR_WLEN8, iobase + UART_LCR);        /* Reset DLAB */
522         outb((UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2), iobase + UART_MCR);
523
524         /* Turn on interrupts */
525         // outb(UART_IER_RLSI | UART_IER_RDI | UART_IER_THRI, iobase + UART_IER);
526
527         spin_unlock_irqrestore(&(info->lock), flags);
528
529         btuart_change_speed(info, DEFAULT_BAUD_RATE);
530
531         /* Timeout before it is safe to send the first HCI packet */
532         msleep(1000);
533
534         /* Register HCI device */
535         if (hci_register_dev(hdev) < 0) {
536                 BT_ERR("Can't register HCI device");
537                 info->hdev = NULL;
538                 hci_free_dev(hdev);
539                 return -ENODEV;
540         }
541
542         return 0;
543 }
544
545
546 static int btuart_close(btuart_info_t *info)
547 {
548         unsigned long flags;
549         unsigned int iobase = info->p_dev->io.BasePort1;
550         struct hci_dev *hdev = info->hdev;
551
552         if (!hdev)
553                 return -ENODEV;
554
555         btuart_hci_close(hdev);
556
557         spin_lock_irqsave(&(info->lock), flags);
558
559         /* Reset UART */
560         outb(0, iobase + UART_MCR);
561
562         /* Turn off interrupts */
563         outb(0, iobase + UART_IER);
564
565         spin_unlock_irqrestore(&(info->lock), flags);
566
567         if (hci_unregister_dev(hdev) < 0)
568                 BT_ERR("Can't unregister HCI device %s", hdev->name);
569
570         hci_free_dev(hdev);
571
572         return 0;
573 }
574
575 static int btuart_probe(struct pcmcia_device *link)
576 {
577         btuart_info_t *info;
578
579         /* Create new info device */
580         info = kzalloc(sizeof(*info), GFP_KERNEL);
581         if (!info)
582                 return -ENOMEM;
583
584         info->p_dev = link;
585         link->priv = info;
586
587         link->io.Attributes1 = IO_DATA_PATH_WIDTH_8;
588         link->io.NumPorts1 = 8;
589         link->irq.Attributes = IRQ_TYPE_EXCLUSIVE | IRQ_HANDLE_PRESENT;
590         link->irq.IRQInfo1 = IRQ_LEVEL_ID;
591
592         link->irq.Handler = btuart_interrupt;
593         link->irq.Instance = info;
594
595         link->conf.Attributes = CONF_ENABLE_IRQ;
596         link->conf.IntType = INT_MEMORY_AND_IO;
597
598         return btuart_config(link);
599 }
600
601
602 static void btuart_detach(struct pcmcia_device *link)
603 {
604         btuart_info_t *info = link->priv;
605
606         btuart_release(link);
607         kfree(info);
608 }
609
610 static int get_tuple(struct pcmcia_device *handle, tuple_t *tuple, cisparse_t *parse)
611 {
612         int i;
613
614         i = pcmcia_get_tuple_data(handle, tuple);
615         if (i != CS_SUCCESS)
616                 return i;
617
618         return pcmcia_parse_tuple(handle, tuple, parse);
619 }
620
621 static int first_tuple(struct pcmcia_device *handle, tuple_t *tuple, cisparse_t *parse)
622 {
623         if (pcmcia_get_first_tuple(handle, tuple) != CS_SUCCESS)
624                 return CS_NO_MORE_ITEMS;
625         return get_tuple(handle, tuple, parse);
626 }
627
628 static int next_tuple(struct pcmcia_device *handle, tuple_t *tuple, cisparse_t *parse)
629 {
630         if (pcmcia_get_next_tuple(handle, tuple) != CS_SUCCESS)
631                 return CS_NO_MORE_ITEMS;
632         return get_tuple(handle, tuple, parse);
633 }
634
635 static int btuart_config(struct pcmcia_device *link)
636 {
637         static unsigned int base[5] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8, 0x0 };
638         btuart_info_t *info = link->priv;
639         tuple_t tuple;
640         u_short buf[256];
641         cisparse_t parse;
642         cistpl_cftable_entry_t *cf = &parse.cftable_entry;
643         int i, j, try;
644
645         /* First pass: look for a config entry that looks normal. */
646         tuple.TupleData = (cisdata_t *) buf;
647         tuple.TupleOffset = 0;
648         tuple.TupleDataMax = 255;
649         tuple.Attributes = 0;
650         tuple.DesiredTuple = CISTPL_CFTABLE_ENTRY;
651         /* Two tries: without IO aliases, then with aliases */
652         for (try = 0; try < 2; try++) {
653                 i = first_tuple(link, &tuple, &parse);
654                 while (i != CS_NO_MORE_ITEMS) {
655                         if (i != CS_SUCCESS)
656                                 goto next_entry;
657                         if (cf->vpp1.present & (1 << CISTPL_POWER_VNOM))
658                                 link->conf.Vpp = cf->vpp1.param[CISTPL_POWER_VNOM] / 10000;
659                         if ((cf->io.nwin > 0) && (cf->io.win[0].len == 8) && (cf->io.win[0].base != 0)) {
660                                 link->conf.ConfigIndex = cf->index;
661                                 link->io.BasePort1 = cf->io.win[0].base;
662                                 link->io.IOAddrLines = (try == 0) ? 16 : cf->io.flags & CISTPL_IO_LINES_MASK;
663                                 i = pcmcia_request_io(link, &link->io);
664                                 if (i == CS_SUCCESS)
665                                         goto found_port;
666                         }
667 next_entry:
668                         i = next_tuple(link, &tuple, &parse);
669                 }
670         }
671
672         /* Second pass: try to find an entry that isn't picky about
673            its base address, then try to grab any standard serial port
674            address, and finally try to get any free port. */
675         i = first_tuple(link, &tuple, &parse);
676         while (i != CS_NO_MORE_ITEMS) {
677                 if ((i == CS_SUCCESS) && (cf->io.nwin > 0)
678                     && ((cf->io.flags & CISTPL_IO_LINES_MASK) <= 3)) {
679                         link->conf.ConfigIndex = cf->index;
680                         for (j = 0; j < 5; j++) {
681                                 link->io.BasePort1 = base[j];
682                                 link->io.IOAddrLines = base[j] ? 16 : 3;
683                                 i = pcmcia_request_io(link, &link->io);
684                                 if (i == CS_SUCCESS)
685                                         goto found_port;
686                         }
687                 }
688                 i = next_tuple(link, &tuple, &parse);
689         }
690
691 found_port:
692         if (i != CS_SUCCESS) {
693                 BT_ERR("No usable port range found");
694                 cs_error(link, RequestIO, i);
695                 goto failed;
696         }
697
698         i = pcmcia_request_irq(link, &link->irq);
699         if (i != CS_SUCCESS) {
700                 cs_error(link, RequestIRQ, i);
701                 link->irq.AssignedIRQ = 0;
702         }
703
704         i = pcmcia_request_configuration(link, &link->conf);
705         if (i != CS_SUCCESS) {
706                 cs_error(link, RequestConfiguration, i);
707                 goto failed;
708         }
709
710         if (btuart_open(info) != 0)
711                 goto failed;
712
713         strcpy(info->node.dev_name, info->hdev->name);
714         link->dev_node = &info->node;
715
716         return 0;
717
718 failed:
719         btuart_release(link);
720         return -ENODEV;
721 }
722
723
724 static void btuart_release(struct pcmcia_device *link)
725 {
726         btuart_info_t *info = link->priv;
727
728         btuart_close(info);
729
730         pcmcia_disable_device(link);
731 }
732
733 static struct pcmcia_device_id btuart_ids[] = {
734         /* don't use this driver. Use serial_cs + hci_uart instead */
735         PCMCIA_DEVICE_NULL
736 };
737 MODULE_DEVICE_TABLE(pcmcia, btuart_ids);
738
739 static struct pcmcia_driver btuart_driver = {
740         .owner          = THIS_MODULE,
741         .drv            = {
742                 .name   = "btuart_cs",
743         },
744         .probe          = btuart_probe,
745         .remove         = btuart_detach,
746         .id_table       = btuart_ids,
747 };
748
749 static int __init init_btuart_cs(void)
750 {
751         return pcmcia_register_driver(&btuart_driver);
752 }
753
754
755 static void __exit exit_btuart_cs(void)
756 {
757         pcmcia_unregister_driver(&btuart_driver);
758 }
759
760 module_init(init_btuart_cs);
761 module_exit(exit_btuart_cs);