Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
[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         if (!info || !info->hdev) {
298                 BT_ERR("Call of irq %d for unknown device", irq);
299                 return IRQ_NONE;
300         }
301
302         iobase = info->p_dev->io.BasePort1;
303
304         spin_lock(&(info->lock));
305
306         iir = inb(iobase + UART_IIR) & UART_IIR_ID;
307         while (iir) {
308
309                 /* Clear interrupt */
310                 lsr = inb(iobase + UART_LSR);
311
312                 switch (iir) {
313                 case UART_IIR_RLSI:
314                         BT_ERR("RLSI");
315                         break;
316                 case UART_IIR_RDI:
317                         /* Receive interrupt */
318                         btuart_receive(info);
319                         break;
320                 case UART_IIR_THRI:
321                         if (lsr & UART_LSR_THRE) {
322                                 /* Transmitter ready for data */
323                                 btuart_write_wakeup(info);
324                         }
325                         break;
326                 default:
327                         BT_ERR("Unhandled IIR=%#x", iir);
328                         break;
329                 }
330
331                 /* Make sure we don't stay here too long */
332                 if (boguscount++ > 100)
333                         break;
334
335                 iir = inb(iobase + UART_IIR) & UART_IIR_ID;
336
337         }
338
339         spin_unlock(&(info->lock));
340
341         return IRQ_HANDLED;
342 }
343
344
345 static void btuart_change_speed(btuart_info_t *info, unsigned int speed)
346 {
347         unsigned long flags;
348         unsigned int iobase;
349         int fcr;                /* FIFO control reg */
350         int lcr;                /* Line control reg */
351         int divisor;
352
353         if (!info) {
354                 BT_ERR("Unknown device");
355                 return;
356         }
357
358         iobase = info->p_dev->io.BasePort1;
359
360         spin_lock_irqsave(&(info->lock), flags);
361
362         /* Turn off interrupts */
363         outb(0, iobase + UART_IER);
364
365         divisor = SPEED_MAX / speed;
366
367         fcr = UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT;
368
369         /* 
370          * Use trigger level 1 to avoid 3 ms. timeout delay at 9600 bps, and
371          * almost 1,7 ms at 19200 bps. At speeds above that we can just forget
372          * about this timeout since it will always be fast enough. 
373          */
374
375         if (speed < 38400)
376                 fcr |= UART_FCR_TRIGGER_1;
377         else
378                 fcr |= UART_FCR_TRIGGER_14;
379
380         /* Bluetooth cards use 8N1 */
381         lcr = UART_LCR_WLEN8;
382
383         outb(UART_LCR_DLAB | lcr, iobase + UART_LCR);   /* Set DLAB */
384         outb(divisor & 0xff, iobase + UART_DLL);        /* Set speed */
385         outb(divisor >> 8, iobase + UART_DLM);
386         outb(lcr, iobase + UART_LCR);   /* Set 8N1  */
387         outb(fcr, iobase + UART_FCR);   /* Enable FIFO's */
388
389         /* Turn on interrups */
390         outb(UART_IER_RLSI | UART_IER_RDI | UART_IER_THRI, iobase + UART_IER);
391
392         spin_unlock_irqrestore(&(info->lock), flags);
393 }
394
395
396
397 /* ======================== HCI interface ======================== */
398
399
400 static int btuart_hci_flush(struct hci_dev *hdev)
401 {
402         btuart_info_t *info = (btuart_info_t *)(hdev->driver_data);
403
404         /* Drop TX queue */
405         skb_queue_purge(&(info->txq));
406
407         return 0;
408 }
409
410
411 static int btuart_hci_open(struct hci_dev *hdev)
412 {
413         set_bit(HCI_RUNNING, &(hdev->flags));
414
415         return 0;
416 }
417
418
419 static int btuart_hci_close(struct hci_dev *hdev)
420 {
421         if (!test_and_clear_bit(HCI_RUNNING, &(hdev->flags)))
422                 return 0;
423
424         btuart_hci_flush(hdev);
425
426         return 0;
427 }
428
429
430 static int btuart_hci_send_frame(struct sk_buff *skb)
431 {
432         btuart_info_t *info;
433         struct hci_dev *hdev = (struct hci_dev *)(skb->dev);
434
435         if (!hdev) {
436                 BT_ERR("Frame for unknown HCI device (hdev=NULL)");
437                 return -ENODEV;
438         }
439
440         info = (btuart_info_t *)(hdev->driver_data);
441
442         switch (bt_cb(skb)->pkt_type) {
443         case HCI_COMMAND_PKT:
444                 hdev->stat.cmd_tx++;
445                 break;
446         case HCI_ACLDATA_PKT:
447                 hdev->stat.acl_tx++;
448                 break;
449         case HCI_SCODATA_PKT:
450                 hdev->stat.sco_tx++;
451                 break;
452         };
453
454         /* Prepend skb with frame type */
455         memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
456         skb_queue_tail(&(info->txq), skb);
457
458         btuart_write_wakeup(info);
459
460         return 0;
461 }
462
463
464 static void btuart_hci_destruct(struct hci_dev *hdev)
465 {
466 }
467
468
469 static int btuart_hci_ioctl(struct hci_dev *hdev, unsigned int cmd, unsigned long arg)
470 {
471         return -ENOIOCTLCMD;
472 }
473
474
475
476 /* ======================== Card services HCI interaction ======================== */
477
478
479 static int btuart_open(btuart_info_t *info)
480 {
481         unsigned long flags;
482         unsigned int iobase = info->p_dev->io.BasePort1;
483         struct hci_dev *hdev;
484
485         spin_lock_init(&(info->lock));
486
487         skb_queue_head_init(&(info->txq));
488
489         info->rx_state = RECV_WAIT_PACKET_TYPE;
490         info->rx_count = 0;
491         info->rx_skb = NULL;
492
493         /* Initialize HCI device */
494         hdev = hci_alloc_dev();
495         if (!hdev) {
496                 BT_ERR("Can't allocate HCI device");
497                 return -ENOMEM;
498         }
499
500         info->hdev = hdev;
501
502         hdev->type = HCI_PCCARD;
503         hdev->driver_data = info;
504         SET_HCIDEV_DEV(hdev, &info->p_dev->dev);
505
506         hdev->open     = btuart_hci_open;
507         hdev->close    = btuart_hci_close;
508         hdev->flush    = btuart_hci_flush;
509         hdev->send     = btuart_hci_send_frame;
510         hdev->destruct = btuart_hci_destruct;
511         hdev->ioctl    = btuart_hci_ioctl;
512
513         hdev->owner = THIS_MODULE;
514
515         spin_lock_irqsave(&(info->lock), flags);
516
517         /* Reset UART */
518         outb(0, iobase + UART_MCR);
519
520         /* Turn off interrupts */
521         outb(0, iobase + UART_IER);
522
523         /* Initialize UART */
524         outb(UART_LCR_WLEN8, iobase + UART_LCR);        /* Reset DLAB */
525         outb((UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2), iobase + UART_MCR);
526
527         /* Turn on interrupts */
528         // outb(UART_IER_RLSI | UART_IER_RDI | UART_IER_THRI, iobase + UART_IER);
529
530         spin_unlock_irqrestore(&(info->lock), flags);
531
532         btuart_change_speed(info, DEFAULT_BAUD_RATE);
533
534         /* Timeout before it is safe to send the first HCI packet */
535         msleep(1000);
536
537         /* Register HCI device */
538         if (hci_register_dev(hdev) < 0) {
539                 BT_ERR("Can't register HCI device");
540                 info->hdev = NULL;
541                 hci_free_dev(hdev);
542                 return -ENODEV;
543         }
544
545         return 0;
546 }
547
548
549 static int btuart_close(btuart_info_t *info)
550 {
551         unsigned long flags;
552         unsigned int iobase = info->p_dev->io.BasePort1;
553         struct hci_dev *hdev = info->hdev;
554
555         if (!hdev)
556                 return -ENODEV;
557
558         btuart_hci_close(hdev);
559
560         spin_lock_irqsave(&(info->lock), flags);
561
562         /* Reset UART */
563         outb(0, iobase + UART_MCR);
564
565         /* Turn off interrupts */
566         outb(0, iobase + UART_IER);
567
568         spin_unlock_irqrestore(&(info->lock), flags);
569
570         if (hci_unregister_dev(hdev) < 0)
571                 BT_ERR("Can't unregister HCI device %s", hdev->name);
572
573         hci_free_dev(hdev);
574
575         return 0;
576 }
577
578 static int btuart_probe(struct pcmcia_device *link)
579 {
580         btuart_info_t *info;
581
582         /* Create new info device */
583         info = kzalloc(sizeof(*info), GFP_KERNEL);
584         if (!info)
585                 return -ENOMEM;
586
587         info->p_dev = link;
588         link->priv = info;
589
590         link->io.Attributes1 = IO_DATA_PATH_WIDTH_8;
591         link->io.NumPorts1 = 8;
592         link->irq.Attributes = IRQ_TYPE_EXCLUSIVE | IRQ_HANDLE_PRESENT;
593         link->irq.IRQInfo1 = IRQ_LEVEL_ID;
594
595         link->irq.Handler = btuart_interrupt;
596         link->irq.Instance = info;
597
598         link->conf.Attributes = CONF_ENABLE_IRQ;
599         link->conf.IntType = INT_MEMORY_AND_IO;
600
601         return btuart_config(link);
602 }
603
604
605 static void btuart_detach(struct pcmcia_device *link)
606 {
607         btuart_info_t *info = link->priv;
608
609         btuart_release(link);
610         kfree(info);
611 }
612
613 static int get_tuple(struct pcmcia_device *handle, tuple_t *tuple, cisparse_t *parse)
614 {
615         int i;
616
617         i = pcmcia_get_tuple_data(handle, tuple);
618         if (i != CS_SUCCESS)
619                 return i;
620
621         return pcmcia_parse_tuple(handle, tuple, parse);
622 }
623
624 static int first_tuple(struct pcmcia_device *handle, tuple_t *tuple, cisparse_t *parse)
625 {
626         if (pcmcia_get_first_tuple(handle, tuple) != CS_SUCCESS)
627                 return CS_NO_MORE_ITEMS;
628         return get_tuple(handle, tuple, parse);
629 }
630
631 static int next_tuple(struct pcmcia_device *handle, tuple_t *tuple, cisparse_t *parse)
632 {
633         if (pcmcia_get_next_tuple(handle, tuple) != CS_SUCCESS)
634                 return CS_NO_MORE_ITEMS;
635         return get_tuple(handle, tuple, parse);
636 }
637
638 static int btuart_config(struct pcmcia_device *link)
639 {
640         static kio_addr_t base[5] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8, 0x0 };
641         btuart_info_t *info = link->priv;
642         tuple_t tuple;
643         u_short buf[256];
644         cisparse_t parse;
645         cistpl_cftable_entry_t *cf = &parse.cftable_entry;
646         int i, j, try;
647
648         /* First pass: look for a config entry that looks normal. */
649         tuple.TupleData = (cisdata_t *) buf;
650         tuple.TupleOffset = 0;
651         tuple.TupleDataMax = 255;
652         tuple.Attributes = 0;
653         tuple.DesiredTuple = CISTPL_CFTABLE_ENTRY;
654         /* Two tries: without IO aliases, then with aliases */
655         for (try = 0; try < 2; try++) {
656                 i = first_tuple(link, &tuple, &parse);
657                 while (i != CS_NO_MORE_ITEMS) {
658                         if (i != CS_SUCCESS)
659                                 goto next_entry;
660                         if (cf->vpp1.present & (1 << CISTPL_POWER_VNOM))
661                                 link->conf.Vpp = cf->vpp1.param[CISTPL_POWER_VNOM] / 10000;
662                         if ((cf->io.nwin > 0) && (cf->io.win[0].len == 8) && (cf->io.win[0].base != 0)) {
663                                 link->conf.ConfigIndex = cf->index;
664                                 link->io.BasePort1 = cf->io.win[0].base;
665                                 link->io.IOAddrLines = (try == 0) ? 16 : cf->io.flags & CISTPL_IO_LINES_MASK;
666                                 i = pcmcia_request_io(link, &link->io);
667                                 if (i == CS_SUCCESS)
668                                         goto found_port;
669                         }
670 next_entry:
671                         i = next_tuple(link, &tuple, &parse);
672                 }
673         }
674
675         /* Second pass: try to find an entry that isn't picky about
676            its base address, then try to grab any standard serial port
677            address, and finally try to get any free port. */
678         i = first_tuple(link, &tuple, &parse);
679         while (i != CS_NO_MORE_ITEMS) {
680                 if ((i == CS_SUCCESS) && (cf->io.nwin > 0)
681                     && ((cf->io.flags & CISTPL_IO_LINES_MASK) <= 3)) {
682                         link->conf.ConfigIndex = cf->index;
683                         for (j = 0; j < 5; j++) {
684                                 link->io.BasePort1 = base[j];
685                                 link->io.IOAddrLines = base[j] ? 16 : 3;
686                                 i = pcmcia_request_io(link, &link->io);
687                                 if (i == CS_SUCCESS)
688                                         goto found_port;
689                         }
690                 }
691                 i = next_tuple(link, &tuple, &parse);
692         }
693
694 found_port:
695         if (i != CS_SUCCESS) {
696                 BT_ERR("No usable port range found");
697                 cs_error(link, RequestIO, i);
698                 goto failed;
699         }
700
701         i = pcmcia_request_irq(link, &link->irq);
702         if (i != CS_SUCCESS) {
703                 cs_error(link, RequestIRQ, i);
704                 link->irq.AssignedIRQ = 0;
705         }
706
707         i = pcmcia_request_configuration(link, &link->conf);
708         if (i != CS_SUCCESS) {
709                 cs_error(link, RequestConfiguration, i);
710                 goto failed;
711         }
712
713         if (btuart_open(info) != 0)
714                 goto failed;
715
716         strcpy(info->node.dev_name, info->hdev->name);
717         link->dev_node = &info->node;
718
719         return 0;
720
721 failed:
722         btuart_release(link);
723         return -ENODEV;
724 }
725
726
727 static void btuart_release(struct pcmcia_device *link)
728 {
729         btuart_info_t *info = link->priv;
730
731         btuart_close(info);
732
733         pcmcia_disable_device(link);
734 }
735
736 static struct pcmcia_device_id btuart_ids[] = {
737         /* don't use this driver. Use serial_cs + hci_uart instead */
738         PCMCIA_DEVICE_NULL
739 };
740 MODULE_DEVICE_TABLE(pcmcia, btuart_ids);
741
742 static struct pcmcia_driver btuart_driver = {
743         .owner          = THIS_MODULE,
744         .drv            = {
745                 .name   = "btuart_cs",
746         },
747         .probe          = btuart_probe,
748         .remove         = btuart_detach,
749         .id_table       = btuart_ids,
750 };
751
752 static int __init init_btuart_cs(void)
753 {
754         return pcmcia_register_driver(&btuart_driver);
755 }
756
757
758 static void __exit exit_btuart_cs(void)
759 {
760         pcmcia_unregister_driver(&btuart_driver);
761 }
762
763 module_init(init_btuart_cs);
764 module_exit(exit_btuart_cs);