Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide
[sfrench/cifs-2.6.git] / drivers / bluetooth / hci_ll.c
1 /*
2  *  Texas Instruments' Bluetooth HCILL UART protocol
3  *
4  *  HCILL (HCI Low Level) is a Texas Instruments' power management
5  *  protocol extension to H4.
6  *
7  *  Copyright (C) 2007 Texas Instruments, Inc.
8  *
9  *  Written by Ohad Ben-Cohen <ohad@bencohen.org>
10  *
11  *  Acknowledgements:
12  *  This file is based on hci_h4.c, which was written
13  *  by Maxim Krasnyansky and Marcel Holtmann.
14  *
15  *  This program is free software; you can redistribute it and/or modify
16  *  it under the terms of the GNU General Public License version 2
17  *  as published by the Free Software Foundation
18  *
19  *  This program is distributed in the hope that it will be useful,
20  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
21  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22  *  GNU General Public License for more details.
23  *
24  *  You should have received a copy of the GNU General Public License
25  *  along with this program; if not, write to the Free Software
26  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
27  *
28  */
29
30 #include <linux/module.h>
31 #include <linux/kernel.h>
32
33 #include <linux/init.h>
34 #include <linux/sched.h>
35 #include <linux/types.h>
36 #include <linux/fcntl.h>
37 #include <linux/firmware.h>
38 #include <linux/interrupt.h>
39 #include <linux/ptrace.h>
40 #include <linux/poll.h>
41
42 #include <linux/slab.h>
43 #include <linux/errno.h>
44 #include <linux/string.h>
45 #include <linux/signal.h>
46 #include <linux/ioctl.h>
47 #include <linux/of.h>
48 #include <linux/serdev.h>
49 #include <linux/skbuff.h>
50 #include <linux/ti_wilink_st.h>
51 #include <linux/clk.h>
52
53 #include <net/bluetooth/bluetooth.h>
54 #include <net/bluetooth/hci_core.h>
55 #include <linux/gpio/consumer.h>
56 #include <linux/nvmem-consumer.h>
57
58 #include "hci_uart.h"
59
60 /* Vendor-specific HCI commands */
61 #define HCI_VS_WRITE_BD_ADDR                    0xfc06
62 #define HCI_VS_UPDATE_UART_HCI_BAUDRATE         0xff36
63
64 /* HCILL commands */
65 #define HCILL_GO_TO_SLEEP_IND   0x30
66 #define HCILL_GO_TO_SLEEP_ACK   0x31
67 #define HCILL_WAKE_UP_IND       0x32
68 #define HCILL_WAKE_UP_ACK       0x33
69
70 /* HCILL states */
71 enum hcill_states_e {
72         HCILL_ASLEEP,
73         HCILL_ASLEEP_TO_AWAKE,
74         HCILL_AWAKE,
75         HCILL_AWAKE_TO_ASLEEP
76 };
77
78 struct ll_device {
79         struct hci_uart hu;
80         struct serdev_device *serdev;
81         struct gpio_desc *enable_gpio;
82         struct clk *ext_clk;
83         bdaddr_t bdaddr;
84 };
85
86 struct ll_struct {
87         struct sk_buff *rx_skb;
88         struct sk_buff_head txq;
89         spinlock_t hcill_lock;          /* HCILL state lock     */
90         unsigned long hcill_state;      /* HCILL power state    */
91         struct sk_buff_head tx_wait_q;  /* HCILL wait queue     */
92 };
93
94 /*
95  * Builds and sends an HCILL command packet.
96  * These are very simple packets with only 1 cmd byte
97  */
98 static int send_hcill_cmd(u8 cmd, struct hci_uart *hu)
99 {
100         int err = 0;
101         struct sk_buff *skb = NULL;
102         struct ll_struct *ll = hu->priv;
103
104         BT_DBG("hu %p cmd 0x%x", hu, cmd);
105
106         /* allocate packet */
107         skb = bt_skb_alloc(1, GFP_ATOMIC);
108         if (!skb) {
109                 BT_ERR("cannot allocate memory for HCILL packet");
110                 err = -ENOMEM;
111                 goto out;
112         }
113
114         /* prepare packet */
115         skb_put_u8(skb, cmd);
116
117         /* send packet */
118         skb_queue_tail(&ll->txq, skb);
119 out:
120         return err;
121 }
122
123 /* Initialize protocol */
124 static int ll_open(struct hci_uart *hu)
125 {
126         struct ll_struct *ll;
127
128         BT_DBG("hu %p", hu);
129
130         ll = kzalloc(sizeof(*ll), GFP_KERNEL);
131         if (!ll)
132                 return -ENOMEM;
133
134         skb_queue_head_init(&ll->txq);
135         skb_queue_head_init(&ll->tx_wait_q);
136         spin_lock_init(&ll->hcill_lock);
137
138         ll->hcill_state = HCILL_AWAKE;
139
140         hu->priv = ll;
141
142         if (hu->serdev) {
143                 struct ll_device *lldev = serdev_device_get_drvdata(hu->serdev);
144                 if (!IS_ERR(lldev->ext_clk))
145                         clk_prepare_enable(lldev->ext_clk);
146         }
147
148         return 0;
149 }
150
151 /* Flush protocol data */
152 static int ll_flush(struct hci_uart *hu)
153 {
154         struct ll_struct *ll = hu->priv;
155
156         BT_DBG("hu %p", hu);
157
158         skb_queue_purge(&ll->tx_wait_q);
159         skb_queue_purge(&ll->txq);
160
161         return 0;
162 }
163
164 /* Close protocol */
165 static int ll_close(struct hci_uart *hu)
166 {
167         struct ll_struct *ll = hu->priv;
168
169         BT_DBG("hu %p", hu);
170
171         skb_queue_purge(&ll->tx_wait_q);
172         skb_queue_purge(&ll->txq);
173
174         kfree_skb(ll->rx_skb);
175
176         if (hu->serdev) {
177                 struct ll_device *lldev = serdev_device_get_drvdata(hu->serdev);
178                 gpiod_set_value_cansleep(lldev->enable_gpio, 0);
179
180                 clk_disable_unprepare(lldev->ext_clk);
181         }
182
183         hu->priv = NULL;
184
185         kfree(ll);
186
187         return 0;
188 }
189
190 /*
191  * internal function, which does common work of the device wake up process:
192  * 1. places all pending packets (waiting in tx_wait_q list) in txq list.
193  * 2. changes internal state to HCILL_AWAKE.
194  * Note: assumes that hcill_lock spinlock is taken,
195  * shouldn't be called otherwise!
196  */
197 static void __ll_do_awake(struct ll_struct *ll)
198 {
199         struct sk_buff *skb = NULL;
200
201         while ((skb = skb_dequeue(&ll->tx_wait_q)))
202                 skb_queue_tail(&ll->txq, skb);
203
204         ll->hcill_state = HCILL_AWAKE;
205 }
206
207 /*
208  * Called upon a wake-up-indication from the device
209  */
210 static void ll_device_want_to_wakeup(struct hci_uart *hu)
211 {
212         unsigned long flags;
213         struct ll_struct *ll = hu->priv;
214
215         BT_DBG("hu %p", hu);
216
217         /* lock hcill state */
218         spin_lock_irqsave(&ll->hcill_lock, flags);
219
220         switch (ll->hcill_state) {
221         case HCILL_ASLEEP_TO_AWAKE:
222                 /*
223                  * This state means that both the host and the BRF chip
224                  * have simultaneously sent a wake-up-indication packet.
225                  * Traditionally, in this case, receiving a wake-up-indication
226                  * was enough and an additional wake-up-ack wasn't needed.
227                  * This has changed with the BRF6350, which does require an
228                  * explicit wake-up-ack. Other BRF versions, which do not
229                  * require an explicit ack here, do accept it, thus it is
230                  * perfectly safe to always send one.
231                  */
232                 BT_DBG("dual wake-up-indication");
233                 /* fall through */
234         case HCILL_ASLEEP:
235                 /* acknowledge device wake up */
236                 if (send_hcill_cmd(HCILL_WAKE_UP_ACK, hu) < 0) {
237                         BT_ERR("cannot acknowledge device wake up");
238                         goto out;
239                 }
240                 break;
241         default:
242                 /* any other state is illegal */
243                 BT_ERR("received HCILL_WAKE_UP_IND in state %ld", ll->hcill_state);
244                 break;
245         }
246
247         /* send pending packets and change state to HCILL_AWAKE */
248         __ll_do_awake(ll);
249
250 out:
251         spin_unlock_irqrestore(&ll->hcill_lock, flags);
252
253         /* actually send the packets */
254         hci_uart_tx_wakeup(hu);
255 }
256
257 /*
258  * Called upon a sleep-indication from the device
259  */
260 static void ll_device_want_to_sleep(struct hci_uart *hu)
261 {
262         unsigned long flags;
263         struct ll_struct *ll = hu->priv;
264
265         BT_DBG("hu %p", hu);
266
267         /* lock hcill state */
268         spin_lock_irqsave(&ll->hcill_lock, flags);
269
270         /* sanity check */
271         if (ll->hcill_state != HCILL_AWAKE)
272                 BT_ERR("ERR: HCILL_GO_TO_SLEEP_IND in state %ld", ll->hcill_state);
273
274         /* acknowledge device sleep */
275         if (send_hcill_cmd(HCILL_GO_TO_SLEEP_ACK, hu) < 0) {
276                 BT_ERR("cannot acknowledge device sleep");
277                 goto out;
278         }
279
280         /* update state */
281         ll->hcill_state = HCILL_ASLEEP;
282
283 out:
284         spin_unlock_irqrestore(&ll->hcill_lock, flags);
285
286         /* actually send the sleep ack packet */
287         hci_uart_tx_wakeup(hu);
288 }
289
290 /*
291  * Called upon wake-up-acknowledgement from the device
292  */
293 static void ll_device_woke_up(struct hci_uart *hu)
294 {
295         unsigned long flags;
296         struct ll_struct *ll = hu->priv;
297
298         BT_DBG("hu %p", hu);
299
300         /* lock hcill state */
301         spin_lock_irqsave(&ll->hcill_lock, flags);
302
303         /* sanity check */
304         if (ll->hcill_state != HCILL_ASLEEP_TO_AWAKE)
305                 BT_ERR("received HCILL_WAKE_UP_ACK in state %ld", ll->hcill_state);
306
307         /* send pending packets and change state to HCILL_AWAKE */
308         __ll_do_awake(ll);
309
310         spin_unlock_irqrestore(&ll->hcill_lock, flags);
311
312         /* actually send the packets */
313         hci_uart_tx_wakeup(hu);
314 }
315
316 /* Enqueue frame for transmittion (padding, crc, etc) */
317 /* may be called from two simultaneous tasklets */
318 static int ll_enqueue(struct hci_uart *hu, struct sk_buff *skb)
319 {
320         unsigned long flags = 0;
321         struct ll_struct *ll = hu->priv;
322
323         BT_DBG("hu %p skb %p", hu, skb);
324
325         /* Prepend skb with frame type */
326         memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
327
328         /* lock hcill state */
329         spin_lock_irqsave(&ll->hcill_lock, flags);
330
331         /* act according to current state */
332         switch (ll->hcill_state) {
333         case HCILL_AWAKE:
334                 BT_DBG("device awake, sending normally");
335                 skb_queue_tail(&ll->txq, skb);
336                 break;
337         case HCILL_ASLEEP:
338                 BT_DBG("device asleep, waking up and queueing packet");
339                 /* save packet for later */
340                 skb_queue_tail(&ll->tx_wait_q, skb);
341                 /* awake device */
342                 if (send_hcill_cmd(HCILL_WAKE_UP_IND, hu) < 0) {
343                         BT_ERR("cannot wake up device");
344                         break;
345                 }
346                 ll->hcill_state = HCILL_ASLEEP_TO_AWAKE;
347                 break;
348         case HCILL_ASLEEP_TO_AWAKE:
349                 BT_DBG("device waking up, queueing packet");
350                 /* transient state; just keep packet for later */
351                 skb_queue_tail(&ll->tx_wait_q, skb);
352                 break;
353         default:
354                 BT_ERR("illegal hcill state: %ld (losing packet)", ll->hcill_state);
355                 kfree_skb(skb);
356                 break;
357         }
358
359         spin_unlock_irqrestore(&ll->hcill_lock, flags);
360
361         return 0;
362 }
363
364 static int ll_recv_frame(struct hci_dev *hdev, struct sk_buff *skb)
365 {
366         struct hci_uart *hu = hci_get_drvdata(hdev);
367         struct ll_struct *ll = hu->priv;
368
369         switch (hci_skb_pkt_type(skb)) {
370         case HCILL_GO_TO_SLEEP_IND:
371                 BT_DBG("HCILL_GO_TO_SLEEP_IND packet");
372                 ll_device_want_to_sleep(hu);
373                 break;
374         case HCILL_GO_TO_SLEEP_ACK:
375                 /* shouldn't happen */
376                 bt_dev_err(hdev, "received HCILL_GO_TO_SLEEP_ACK in state %ld",
377                            ll->hcill_state);
378                 break;
379         case HCILL_WAKE_UP_IND:
380                 BT_DBG("HCILL_WAKE_UP_IND packet");
381                 ll_device_want_to_wakeup(hu);
382                 break;
383         case HCILL_WAKE_UP_ACK:
384                 BT_DBG("HCILL_WAKE_UP_ACK packet");
385                 ll_device_woke_up(hu);
386                 break;
387         }
388
389         kfree_skb(skb);
390         return 0;
391 }
392
393 #define LL_RECV_SLEEP_IND \
394         .type = HCILL_GO_TO_SLEEP_IND, \
395         .hlen = 0, \
396         .loff = 0, \
397         .lsize = 0, \
398         .maxlen = 0
399
400 #define LL_RECV_SLEEP_ACK \
401         .type = HCILL_GO_TO_SLEEP_ACK, \
402         .hlen = 0, \
403         .loff = 0, \
404         .lsize = 0, \
405         .maxlen = 0
406
407 #define LL_RECV_WAKE_IND \
408         .type = HCILL_WAKE_UP_IND, \
409         .hlen = 0, \
410         .loff = 0, \
411         .lsize = 0, \
412         .maxlen = 0
413
414 #define LL_RECV_WAKE_ACK \
415         .type = HCILL_WAKE_UP_ACK, \
416         .hlen = 0, \
417         .loff = 0, \
418         .lsize = 0, \
419         .maxlen = 0
420
421 static const struct h4_recv_pkt ll_recv_pkts[] = {
422         { H4_RECV_ACL,       .recv = hci_recv_frame },
423         { H4_RECV_SCO,       .recv = hci_recv_frame },
424         { H4_RECV_EVENT,     .recv = hci_recv_frame },
425         { LL_RECV_SLEEP_IND, .recv = ll_recv_frame  },
426         { LL_RECV_SLEEP_ACK, .recv = ll_recv_frame  },
427         { LL_RECV_WAKE_IND,  .recv = ll_recv_frame  },
428         { LL_RECV_WAKE_ACK,  .recv = ll_recv_frame  },
429 };
430
431 /* Recv data */
432 static int ll_recv(struct hci_uart *hu, const void *data, int count)
433 {
434         struct ll_struct *ll = hu->priv;
435
436         if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
437                 return -EUNATCH;
438
439         ll->rx_skb = h4_recv_buf(hu->hdev, ll->rx_skb, data, count,
440                                  ll_recv_pkts, ARRAY_SIZE(ll_recv_pkts));
441         if (IS_ERR(ll->rx_skb)) {
442                 int err = PTR_ERR(ll->rx_skb);
443                 bt_dev_err(hu->hdev, "Frame reassembly failed (%d)", err);
444                 ll->rx_skb = NULL;
445                 return err;
446         }
447
448         return count;
449 }
450
451 static struct sk_buff *ll_dequeue(struct hci_uart *hu)
452 {
453         struct ll_struct *ll = hu->priv;
454         return skb_dequeue(&ll->txq);
455 }
456
457 #if IS_ENABLED(CONFIG_SERIAL_DEV_BUS)
458 static int read_local_version(struct hci_dev *hdev)
459 {
460         int err = 0;
461         unsigned short version = 0;
462         struct sk_buff *skb;
463         struct hci_rp_read_local_version *ver;
464
465         skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL, HCI_INIT_TIMEOUT);
466         if (IS_ERR(skb)) {
467                 bt_dev_err(hdev, "Reading TI version information failed (%ld)",
468                            PTR_ERR(skb));
469                 return PTR_ERR(skb);
470         }
471         if (skb->len != sizeof(*ver)) {
472                 err = -EILSEQ;
473                 goto out;
474         }
475
476         ver = (struct hci_rp_read_local_version *)skb->data;
477         if (le16_to_cpu(ver->manufacturer) != 13) {
478                 err = -ENODEV;
479                 goto out;
480         }
481
482         version = le16_to_cpu(ver->lmp_subver);
483
484 out:
485         if (err) bt_dev_err(hdev, "Failed to read TI version info: %d", err);
486         kfree_skb(skb);
487         return err ? err : version;
488 }
489
490 /**
491  * download_firmware -
492  *      internal function which parses through the .bts firmware
493  *      script file intreprets SEND, DELAY actions only as of now
494  */
495 static int download_firmware(struct ll_device *lldev)
496 {
497         unsigned short chip, min_ver, maj_ver;
498         int version, err, len;
499         unsigned char *ptr, *action_ptr;
500         unsigned char bts_scr_name[40]; /* 40 char long bts scr name? */
501         const struct firmware *fw;
502         struct sk_buff *skb;
503         struct hci_command *cmd;
504
505         version = read_local_version(lldev->hu.hdev);
506         if (version < 0)
507                 return version;
508
509         chip = (version & 0x7C00) >> 10;
510         min_ver = (version & 0x007F);
511         maj_ver = (version & 0x0380) >> 7;
512         if (version & 0x8000)
513                 maj_ver |= 0x0008;
514
515         snprintf(bts_scr_name, sizeof(bts_scr_name),
516                  "ti-connectivity/TIInit_%d.%d.%d.bts",
517                  chip, maj_ver, min_ver);
518
519         err = request_firmware(&fw, bts_scr_name, &lldev->serdev->dev);
520         if (err || !fw->data || !fw->size) {
521                 bt_dev_err(lldev->hu.hdev, "request_firmware failed(errno %d) for %s",
522                            err, bts_scr_name);
523                 return -EINVAL;
524         }
525         ptr = (void *)fw->data;
526         len = fw->size;
527         /* bts_header to remove out magic number and
528          * version
529          */
530         ptr += sizeof(struct bts_header);
531         len -= sizeof(struct bts_header);
532
533         while (len > 0 && ptr) {
534                 bt_dev_dbg(lldev->hu.hdev, " action size %d, type %d ",
535                            ((struct bts_action *)ptr)->size,
536                            ((struct bts_action *)ptr)->type);
537
538                 action_ptr = &(((struct bts_action *)ptr)->data[0]);
539
540                 switch (((struct bts_action *)ptr)->type) {
541                 case ACTION_SEND_COMMAND:       /* action send */
542                         bt_dev_dbg(lldev->hu.hdev, "S");
543                         cmd = (struct hci_command *)action_ptr;
544                         if (cmd->opcode == HCI_VS_UPDATE_UART_HCI_BAUDRATE) {
545                                 /* ignore remote change
546                                  * baud rate HCI VS command
547                                  */
548                                 bt_dev_warn(lldev->hu.hdev, "change remote baud rate command in firmware");
549                                 break;
550                         }
551                         if (cmd->prefix != 1)
552                                 bt_dev_dbg(lldev->hu.hdev, "command type %d", cmd->prefix);
553
554                         skb = __hci_cmd_sync(lldev->hu.hdev, cmd->opcode, cmd->plen, &cmd->speed, HCI_INIT_TIMEOUT);
555                         if (IS_ERR(skb)) {
556                                 bt_dev_err(lldev->hu.hdev, "send command failed");
557                                 err = PTR_ERR(skb);
558                                 goto out_rel_fw;
559                         }
560                         kfree_skb(skb);
561                         break;
562                 case ACTION_WAIT_EVENT:  /* wait */
563                         /* no need to wait as command was synchronous */
564                         bt_dev_dbg(lldev->hu.hdev, "W");
565                         break;
566                 case ACTION_DELAY:      /* sleep */
567                         bt_dev_info(lldev->hu.hdev, "sleep command in scr");
568                         msleep(((struct bts_action_delay *)action_ptr)->msec);
569                         break;
570                 }
571                 len -= (sizeof(struct bts_action) +
572                         ((struct bts_action *)ptr)->size);
573                 ptr += sizeof(struct bts_action) +
574                         ((struct bts_action *)ptr)->size;
575         }
576
577 out_rel_fw:
578         /* fw download complete */
579         release_firmware(fw);
580         return err;
581 }
582
583 static int ll_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
584 {
585         bdaddr_t bdaddr_swapped;
586         struct sk_buff *skb;
587
588         /* HCI_VS_WRITE_BD_ADDR (at least on a CC2560A chip) expects the BD
589          * address to be MSB first, but bdaddr_t has the convention of being
590          * LSB first.
591          */
592         baswap(&bdaddr_swapped, bdaddr);
593         skb = __hci_cmd_sync(hdev, HCI_VS_WRITE_BD_ADDR, sizeof(bdaddr_t),
594                              &bdaddr_swapped, HCI_INIT_TIMEOUT);
595         if (!IS_ERR(skb))
596                 kfree_skb(skb);
597
598         return PTR_ERR_OR_ZERO(skb);
599 }
600
601 static int ll_setup(struct hci_uart *hu)
602 {
603         int err, retry = 3;
604         struct ll_device *lldev;
605         struct serdev_device *serdev = hu->serdev;
606         u32 speed;
607
608         if (!serdev)
609                 return 0;
610
611         lldev = serdev_device_get_drvdata(serdev);
612
613         hu->hdev->set_bdaddr = ll_set_bdaddr;
614
615         serdev_device_set_flow_control(serdev, true);
616
617         do {
618                 /* Reset the Bluetooth device */
619                 gpiod_set_value_cansleep(lldev->enable_gpio, 0);
620                 msleep(5);
621                 gpiod_set_value_cansleep(lldev->enable_gpio, 1);
622                 err = serdev_device_wait_for_cts(serdev, true, 200);
623                 if (err) {
624                         bt_dev_err(hu->hdev, "Failed to get CTS");
625                         return err;
626                 }
627
628                 err = download_firmware(lldev);
629                 if (!err)
630                         break;
631
632                 /* Toggle BT_EN and retry */
633                 bt_dev_err(hu->hdev, "download firmware failed, retrying...");
634         } while (retry--);
635
636         if (err)
637                 return err;
638
639         /* Set BD address if one was specified at probe */
640         if (!bacmp(&lldev->bdaddr, BDADDR_NONE)) {
641                 /* This means that there was an error getting the BD address
642                  * during probe, so mark the device as having a bad address.
643                  */
644                 set_bit(HCI_QUIRK_INVALID_BDADDR, &hu->hdev->quirks);
645         } else if (bacmp(&lldev->bdaddr, BDADDR_ANY)) {
646                 err = ll_set_bdaddr(hu->hdev, &lldev->bdaddr);
647                 if (err)
648                         set_bit(HCI_QUIRK_INVALID_BDADDR, &hu->hdev->quirks);
649         }
650
651         /* Operational speed if any */
652         if (hu->oper_speed)
653                 speed = hu->oper_speed;
654         else if (hu->proto->oper_speed)
655                 speed = hu->proto->oper_speed;
656         else
657                 speed = 0;
658
659         if (speed) {
660                 __le32 speed_le = cpu_to_le32(speed);
661                 struct sk_buff *skb;
662
663                 skb = __hci_cmd_sync(hu->hdev, HCI_VS_UPDATE_UART_HCI_BAUDRATE,
664                                      sizeof(speed_le), &speed_le,
665                                      HCI_INIT_TIMEOUT);
666                 if (!IS_ERR(skb)) {
667                         kfree_skb(skb);
668                         serdev_device_set_baudrate(serdev, speed);
669                 }
670         }
671
672         return 0;
673 }
674
675 static const struct hci_uart_proto llp;
676
677 static int hci_ti_probe(struct serdev_device *serdev)
678 {
679         struct hci_uart *hu;
680         struct ll_device *lldev;
681         struct nvmem_cell *bdaddr_cell;
682         u32 max_speed = 3000000;
683
684         lldev = devm_kzalloc(&serdev->dev, sizeof(struct ll_device), GFP_KERNEL);
685         if (!lldev)
686                 return -ENOMEM;
687         hu = &lldev->hu;
688
689         serdev_device_set_drvdata(serdev, lldev);
690         lldev->serdev = hu->serdev = serdev;
691
692         lldev->enable_gpio = devm_gpiod_get_optional(&serdev->dev, "enable", GPIOD_OUT_LOW);
693         if (IS_ERR(lldev->enable_gpio))
694                 return PTR_ERR(lldev->enable_gpio);
695
696         lldev->ext_clk = devm_clk_get(&serdev->dev, "ext_clock");
697         if (IS_ERR(lldev->ext_clk) && PTR_ERR(lldev->ext_clk) != -ENOENT)
698                 return PTR_ERR(lldev->ext_clk);
699
700         of_property_read_u32(serdev->dev.of_node, "max-speed", &max_speed);
701         hci_uart_set_speeds(hu, 115200, max_speed);
702
703         /* optional BD address from nvram */
704         bdaddr_cell = nvmem_cell_get(&serdev->dev, "bd-address");
705         if (IS_ERR(bdaddr_cell)) {
706                 int err = PTR_ERR(bdaddr_cell);
707
708                 if (err == -EPROBE_DEFER)
709                         return err;
710
711                 /* ENOENT means there is no matching nvmem cell and ENOSYS
712                  * means that nvmem is not enabled in the kernel configuration.
713                  */
714                 if (err != -ENOENT && err != -ENOSYS) {
715                         /* If there was some other error, give userspace a
716                          * chance to fix the problem instead of failing to load
717                          * the driver. Using BDADDR_NONE as a flag that is
718                          * tested later in the setup function.
719                          */
720                         dev_warn(&serdev->dev,
721                                  "Failed to get \"bd-address\" nvmem cell (%d)\n",
722                                  err);
723                         bacpy(&lldev->bdaddr, BDADDR_NONE);
724                 }
725         } else {
726                 bdaddr_t *bdaddr;
727                 size_t len;
728
729                 bdaddr = nvmem_cell_read(bdaddr_cell, &len);
730                 nvmem_cell_put(bdaddr_cell);
731                 if (IS_ERR(bdaddr)) {
732                         dev_err(&serdev->dev, "Failed to read nvmem bd-address\n");
733                         return PTR_ERR(bdaddr);
734                 }
735                 if (len != sizeof(bdaddr_t)) {
736                         dev_err(&serdev->dev, "Invalid nvmem bd-address length\n");
737                         kfree(bdaddr);
738                         return -EINVAL;
739                 }
740
741                 /* As per the device tree bindings, the value from nvmem is
742                  * expected to be MSB first, but in the kernel it is expected
743                  * that bdaddr_t is LSB first.
744                  */
745                 baswap(&lldev->bdaddr, bdaddr);
746                 kfree(bdaddr);
747         }
748
749         return hci_uart_register_device(hu, &llp);
750 }
751
752 static void hci_ti_remove(struct serdev_device *serdev)
753 {
754         struct ll_device *lldev = serdev_device_get_drvdata(serdev);
755
756         hci_uart_unregister_device(&lldev->hu);
757 }
758
759 static const struct of_device_id hci_ti_of_match[] = {
760         { .compatible = "ti,cc2560" },
761         { .compatible = "ti,wl1271-st" },
762         { .compatible = "ti,wl1273-st" },
763         { .compatible = "ti,wl1281-st" },
764         { .compatible = "ti,wl1283-st" },
765         { .compatible = "ti,wl1285-st" },
766         { .compatible = "ti,wl1801-st" },
767         { .compatible = "ti,wl1805-st" },
768         { .compatible = "ti,wl1807-st" },
769         { .compatible = "ti,wl1831-st" },
770         { .compatible = "ti,wl1835-st" },
771         { .compatible = "ti,wl1837-st" },
772         {},
773 };
774 MODULE_DEVICE_TABLE(of, hci_ti_of_match);
775
776 static struct serdev_device_driver hci_ti_drv = {
777         .driver         = {
778                 .name   = "hci-ti",
779                 .of_match_table = of_match_ptr(hci_ti_of_match),
780         },
781         .probe  = hci_ti_probe,
782         .remove = hci_ti_remove,
783 };
784 #else
785 #define ll_setup NULL
786 #endif
787
788 static const struct hci_uart_proto llp = {
789         .id             = HCI_UART_LL,
790         .name           = "LL",
791         .setup          = ll_setup,
792         .open           = ll_open,
793         .close          = ll_close,
794         .recv           = ll_recv,
795         .enqueue        = ll_enqueue,
796         .dequeue        = ll_dequeue,
797         .flush          = ll_flush,
798 };
799
800 int __init ll_init(void)
801 {
802         serdev_device_driver_register(&hci_ti_drv);
803
804         return hci_uart_register_proto(&llp);
805 }
806
807 int __exit ll_deinit(void)
808 {
809         serdev_device_driver_unregister(&hci_ti_drv);
810
811         return hci_uart_unregister_proto(&llp);
812 }