1 // SPDX-License-Identifier: GPL-2.0-only
3 * Texas Instruments' Bluetooth HCILL UART protocol
5 * HCILL (HCI Low Level) is a Texas Instruments' power management
6 * protocol extension to H4.
8 * Copyright (C) 2007 Texas Instruments, Inc.
10 * Written by Ohad Ben-Cohen <ohad@bencohen.org>
13 * This file is based on hci_h4.c, which was written
14 * by Maxim Krasnyansky and Marcel Holtmann.
17 #include <linux/module.h>
18 #include <linux/kernel.h>
20 #include <linux/init.h>
21 #include <linux/sched.h>
22 #include <linux/types.h>
23 #include <linux/fcntl.h>
24 #include <linux/firmware.h>
25 #include <linux/interrupt.h>
26 #include <linux/ptrace.h>
27 #include <linux/poll.h>
29 #include <linux/slab.h>
30 #include <linux/errno.h>
31 #include <linux/string.h>
32 #include <linux/signal.h>
33 #include <linux/ioctl.h>
35 #include <linux/serdev.h>
36 #include <linux/skbuff.h>
37 #include <linux/ti_wilink_st.h>
38 #include <linux/clk.h>
40 #include <net/bluetooth/bluetooth.h>
41 #include <net/bluetooth/hci_core.h>
42 #include <linux/gpio/consumer.h>
43 #include <linux/nvmem-consumer.h>
47 /* Vendor-specific HCI commands */
48 #define HCI_VS_WRITE_BD_ADDR 0xfc06
49 #define HCI_VS_UPDATE_UART_HCI_BAUDRATE 0xff36
52 #define HCILL_GO_TO_SLEEP_IND 0x30
53 #define HCILL_GO_TO_SLEEP_ACK 0x31
54 #define HCILL_WAKE_UP_IND 0x32
55 #define HCILL_WAKE_UP_ACK 0x33
60 HCILL_ASLEEP_TO_AWAKE
,
67 struct serdev_device
*serdev
;
68 struct gpio_desc
*enable_gpio
;
74 struct sk_buff
*rx_skb
;
75 struct sk_buff_head txq
;
76 spinlock_t hcill_lock
; /* HCILL state lock */
77 unsigned long hcill_state
; /* HCILL power state */
78 struct sk_buff_head tx_wait_q
; /* HCILL wait queue */
82 * Builds and sends an HCILL command packet.
83 * These are very simple packets with only 1 cmd byte
85 static int send_hcill_cmd(u8 cmd
, struct hci_uart
*hu
)
88 struct sk_buff
*skb
= NULL
;
89 struct ll_struct
*ll
= hu
->priv
;
91 BT_DBG("hu %p cmd 0x%x", hu
, cmd
);
94 skb
= bt_skb_alloc(1, GFP_ATOMIC
);
96 BT_ERR("cannot allocate memory for HCILL packet");
102 skb_put_u8(skb
, cmd
);
105 skb_queue_tail(&ll
->txq
, skb
);
110 /* Initialize protocol */
111 static int ll_open(struct hci_uart
*hu
)
113 struct ll_struct
*ll
;
117 ll
= kzalloc(sizeof(*ll
), GFP_KERNEL
);
121 skb_queue_head_init(&ll
->txq
);
122 skb_queue_head_init(&ll
->tx_wait_q
);
123 spin_lock_init(&ll
->hcill_lock
);
125 ll
->hcill_state
= HCILL_AWAKE
;
130 struct ll_device
*lldev
= serdev_device_get_drvdata(hu
->serdev
);
132 if (!IS_ERR(lldev
->ext_clk
))
133 clk_prepare_enable(lldev
->ext_clk
);
139 /* Flush protocol data */
140 static int ll_flush(struct hci_uart
*hu
)
142 struct ll_struct
*ll
= hu
->priv
;
146 skb_queue_purge(&ll
->tx_wait_q
);
147 skb_queue_purge(&ll
->txq
);
153 static int ll_close(struct hci_uart
*hu
)
155 struct ll_struct
*ll
= hu
->priv
;
159 skb_queue_purge(&ll
->tx_wait_q
);
160 skb_queue_purge(&ll
->txq
);
162 kfree_skb(ll
->rx_skb
);
165 struct ll_device
*lldev
= serdev_device_get_drvdata(hu
->serdev
);
167 gpiod_set_value_cansleep(lldev
->enable_gpio
, 0);
169 clk_disable_unprepare(lldev
->ext_clk
);
180 * internal function, which does common work of the device wake up process:
181 * 1. places all pending packets (waiting in tx_wait_q list) in txq list.
182 * 2. changes internal state to HCILL_AWAKE.
183 * Note: assumes that hcill_lock spinlock is taken,
184 * shouldn't be called otherwise!
186 static void __ll_do_awake(struct ll_struct
*ll
)
188 struct sk_buff
*skb
= NULL
;
190 while ((skb
= skb_dequeue(&ll
->tx_wait_q
)))
191 skb_queue_tail(&ll
->txq
, skb
);
193 ll
->hcill_state
= HCILL_AWAKE
;
197 * Called upon a wake-up-indication from the device
199 static void ll_device_want_to_wakeup(struct hci_uart
*hu
)
202 struct ll_struct
*ll
= hu
->priv
;
206 /* lock hcill state */
207 spin_lock_irqsave(&ll
->hcill_lock
, flags
);
209 switch (ll
->hcill_state
) {
210 case HCILL_ASLEEP_TO_AWAKE
:
212 * This state means that both the host and the BRF chip
213 * have simultaneously sent a wake-up-indication packet.
214 * Traditionally, in this case, receiving a wake-up-indication
215 * was enough and an additional wake-up-ack wasn't needed.
216 * This has changed with the BRF6350, which does require an
217 * explicit wake-up-ack. Other BRF versions, which do not
218 * require an explicit ack here, do accept it, thus it is
219 * perfectly safe to always send one.
221 BT_DBG("dual wake-up-indication");
224 /* acknowledge device wake up */
225 if (send_hcill_cmd(HCILL_WAKE_UP_ACK
, hu
) < 0) {
226 BT_ERR("cannot acknowledge device wake up");
231 /* any other state is illegal */
232 BT_ERR("received HCILL_WAKE_UP_IND in state %ld",
237 /* send pending packets and change state to HCILL_AWAKE */
241 spin_unlock_irqrestore(&ll
->hcill_lock
, flags
);
243 /* actually send the packets */
244 hci_uart_tx_wakeup(hu
);
248 * Called upon a sleep-indication from the device
250 static void ll_device_want_to_sleep(struct hci_uart
*hu
)
253 struct ll_struct
*ll
= hu
->priv
;
257 /* lock hcill state */
258 spin_lock_irqsave(&ll
->hcill_lock
, flags
);
261 if (ll
->hcill_state
!= HCILL_AWAKE
)
262 BT_ERR("ERR: HCILL_GO_TO_SLEEP_IND in state %ld",
265 /* acknowledge device sleep */
266 if (send_hcill_cmd(HCILL_GO_TO_SLEEP_ACK
, hu
) < 0) {
267 BT_ERR("cannot acknowledge device sleep");
272 ll
->hcill_state
= HCILL_ASLEEP
;
275 spin_unlock_irqrestore(&ll
->hcill_lock
, flags
);
277 /* actually send the sleep ack packet */
278 hci_uart_tx_wakeup(hu
);
282 * Called upon wake-up-acknowledgement from the device
284 static void ll_device_woke_up(struct hci_uart
*hu
)
287 struct ll_struct
*ll
= hu
->priv
;
291 /* lock hcill state */
292 spin_lock_irqsave(&ll
->hcill_lock
, flags
);
295 if (ll
->hcill_state
!= HCILL_ASLEEP_TO_AWAKE
)
296 BT_ERR("received HCILL_WAKE_UP_ACK in state %ld",
299 /* send pending packets and change state to HCILL_AWAKE */
302 spin_unlock_irqrestore(&ll
->hcill_lock
, flags
);
304 /* actually send the packets */
305 hci_uart_tx_wakeup(hu
);
308 /* Enqueue frame for transmittion (padding, crc, etc) */
309 /* may be called from two simultaneous tasklets */
310 static int ll_enqueue(struct hci_uart
*hu
, struct sk_buff
*skb
)
312 unsigned long flags
= 0;
313 struct ll_struct
*ll
= hu
->priv
;
315 BT_DBG("hu %p skb %p", hu
, skb
);
317 /* Prepend skb with frame type */
318 memcpy(skb_push(skb
, 1), &hci_skb_pkt_type(skb
), 1);
320 /* lock hcill state */
321 spin_lock_irqsave(&ll
->hcill_lock
, flags
);
323 /* act according to current state */
324 switch (ll
->hcill_state
) {
326 BT_DBG("device awake, sending normally");
327 skb_queue_tail(&ll
->txq
, skb
);
330 BT_DBG("device asleep, waking up and queueing packet");
331 /* save packet for later */
332 skb_queue_tail(&ll
->tx_wait_q
, skb
);
334 if (send_hcill_cmd(HCILL_WAKE_UP_IND
, hu
) < 0) {
335 BT_ERR("cannot wake up device");
338 ll
->hcill_state
= HCILL_ASLEEP_TO_AWAKE
;
340 case HCILL_ASLEEP_TO_AWAKE
:
341 BT_DBG("device waking up, queueing packet");
342 /* transient state; just keep packet for later */
343 skb_queue_tail(&ll
->tx_wait_q
, skb
);
346 BT_ERR("illegal hcill state: %ld (losing packet)",
352 spin_unlock_irqrestore(&ll
->hcill_lock
, flags
);
357 static int ll_recv_frame(struct hci_dev
*hdev
, struct sk_buff
*skb
)
359 struct hci_uart
*hu
= hci_get_drvdata(hdev
);
360 struct ll_struct
*ll
= hu
->priv
;
362 switch (hci_skb_pkt_type(skb
)) {
363 case HCILL_GO_TO_SLEEP_IND
:
364 BT_DBG("HCILL_GO_TO_SLEEP_IND packet");
365 ll_device_want_to_sleep(hu
);
367 case HCILL_GO_TO_SLEEP_ACK
:
368 /* shouldn't happen */
369 bt_dev_err(hdev
, "received HCILL_GO_TO_SLEEP_ACK in state %ld",
372 case HCILL_WAKE_UP_IND
:
373 BT_DBG("HCILL_WAKE_UP_IND packet");
374 ll_device_want_to_wakeup(hu
);
376 case HCILL_WAKE_UP_ACK
:
377 BT_DBG("HCILL_WAKE_UP_ACK packet");
378 ll_device_woke_up(hu
);
386 #define LL_RECV_SLEEP_IND \
387 .type = HCILL_GO_TO_SLEEP_IND, \
393 #define LL_RECV_SLEEP_ACK \
394 .type = HCILL_GO_TO_SLEEP_ACK, \
400 #define LL_RECV_WAKE_IND \
401 .type = HCILL_WAKE_UP_IND, \
407 #define LL_RECV_WAKE_ACK \
408 .type = HCILL_WAKE_UP_ACK, \
414 static const struct h4_recv_pkt ll_recv_pkts
[] = {
415 { H4_RECV_ACL
, .recv
= hci_recv_frame
},
416 { H4_RECV_SCO
, .recv
= hci_recv_frame
},
417 { H4_RECV_EVENT
, .recv
= hci_recv_frame
},
418 { LL_RECV_SLEEP_IND
, .recv
= ll_recv_frame
},
419 { LL_RECV_SLEEP_ACK
, .recv
= ll_recv_frame
},
420 { LL_RECV_WAKE_IND
, .recv
= ll_recv_frame
},
421 { LL_RECV_WAKE_ACK
, .recv
= ll_recv_frame
},
425 static int ll_recv(struct hci_uart
*hu
, const void *data
, int count
)
427 struct ll_struct
*ll
= hu
->priv
;
429 if (!test_bit(HCI_UART_REGISTERED
, &hu
->flags
))
432 ll
->rx_skb
= h4_recv_buf(hu
->hdev
, ll
->rx_skb
, data
, count
,
433 ll_recv_pkts
, ARRAY_SIZE(ll_recv_pkts
));
434 if (IS_ERR(ll
->rx_skb
)) {
435 int err
= PTR_ERR(ll
->rx_skb
);
436 bt_dev_err(hu
->hdev
, "Frame reassembly failed (%d)", err
);
444 static struct sk_buff
*ll_dequeue(struct hci_uart
*hu
)
446 struct ll_struct
*ll
= hu
->priv
;
448 return skb_dequeue(&ll
->txq
);
451 #if IS_ENABLED(CONFIG_SERIAL_DEV_BUS)
452 static int read_local_version(struct hci_dev
*hdev
)
455 unsigned short version
= 0;
457 struct hci_rp_read_local_version
*ver
;
459 skb
= __hci_cmd_sync(hdev
, HCI_OP_READ_LOCAL_VERSION
, 0, NULL
,
462 bt_dev_err(hdev
, "Reading TI version information failed (%ld)",
466 if (skb
->len
!= sizeof(*ver
)) {
471 ver
= (struct hci_rp_read_local_version
*)skb
->data
;
472 if (le16_to_cpu(ver
->manufacturer
) != 13) {
477 version
= le16_to_cpu(ver
->lmp_subver
);
481 bt_dev_err(hdev
, "Failed to read TI version info: %d", err
);
483 return err
? err
: version
;
486 static int send_command_from_firmware(struct ll_device
*lldev
,
487 struct hci_command
*cmd
)
491 if (cmd
->opcode
== HCI_VS_UPDATE_UART_HCI_BAUDRATE
) {
492 /* ignore remote change
493 * baud rate HCI VS command
495 bt_dev_warn(lldev
->hu
.hdev
,
496 "change remote baud rate command in firmware");
499 if (cmd
->prefix
!= 1)
500 bt_dev_dbg(lldev
->hu
.hdev
, "command type %d", cmd
->prefix
);
502 skb
= __hci_cmd_sync(lldev
->hu
.hdev
, cmd
->opcode
, cmd
->plen
,
503 &cmd
->speed
, HCI_INIT_TIMEOUT
);
505 bt_dev_err(lldev
->hu
.hdev
, "send command failed");
513 * download_firmware -
514 * internal function which parses through the .bts firmware
515 * script file intreprets SEND, DELAY actions only as of now
517 static int download_firmware(struct ll_device
*lldev
)
519 unsigned short chip
, min_ver
, maj_ver
;
520 int version
, err
, len
;
521 unsigned char *ptr
, *action_ptr
;
522 unsigned char bts_scr_name
[40]; /* 40 char long bts scr name? */
523 const struct firmware
*fw
;
524 struct hci_command
*cmd
;
526 version
= read_local_version(lldev
->hu
.hdev
);
530 chip
= (version
& 0x7C00) >> 10;
531 min_ver
= (version
& 0x007F);
532 maj_ver
= (version
& 0x0380) >> 7;
533 if (version
& 0x8000)
536 snprintf(bts_scr_name
, sizeof(bts_scr_name
),
537 "ti-connectivity/TIInit_%d.%d.%d.bts",
538 chip
, maj_ver
, min_ver
);
540 err
= request_firmware(&fw
, bts_scr_name
, &lldev
->serdev
->dev
);
541 if (err
|| !fw
->data
|| !fw
->size
) {
542 bt_dev_err(lldev
->hu
.hdev
, "request_firmware failed(errno %d) for %s",
546 ptr
= (void *)fw
->data
;
548 /* bts_header to remove out magic number and
551 ptr
+= sizeof(struct bts_header
);
552 len
-= sizeof(struct bts_header
);
554 while (len
> 0 && ptr
) {
555 bt_dev_dbg(lldev
->hu
.hdev
, " action size %d, type %d ",
556 ((struct bts_action
*)ptr
)->size
,
557 ((struct bts_action
*)ptr
)->type
);
559 action_ptr
= &(((struct bts_action
*)ptr
)->data
[0]);
561 switch (((struct bts_action
*)ptr
)->type
) {
562 case ACTION_SEND_COMMAND
: /* action send */
563 bt_dev_dbg(lldev
->hu
.hdev
, "S");
564 cmd
= (struct hci_command
*)action_ptr
;
565 err
= send_command_from_firmware(lldev
, cmd
);
569 case ACTION_WAIT_EVENT
: /* wait */
570 /* no need to wait as command was synchronous */
571 bt_dev_dbg(lldev
->hu
.hdev
, "W");
573 case ACTION_DELAY
: /* sleep */
574 bt_dev_info(lldev
->hu
.hdev
, "sleep command in scr");
575 msleep(((struct bts_action_delay
*)action_ptr
)->msec
);
578 len
-= (sizeof(struct bts_action
) +
579 ((struct bts_action
*)ptr
)->size
);
580 ptr
+= sizeof(struct bts_action
) +
581 ((struct bts_action
*)ptr
)->size
;
585 /* fw download complete */
586 release_firmware(fw
);
590 static int ll_set_bdaddr(struct hci_dev
*hdev
, const bdaddr_t
*bdaddr
)
592 bdaddr_t bdaddr_swapped
;
595 /* HCI_VS_WRITE_BD_ADDR (at least on a CC2560A chip) expects the BD
596 * address to be MSB first, but bdaddr_t has the convention of being
599 baswap(&bdaddr_swapped
, bdaddr
);
600 skb
= __hci_cmd_sync(hdev
, HCI_VS_WRITE_BD_ADDR
, sizeof(bdaddr_t
),
601 &bdaddr_swapped
, HCI_INIT_TIMEOUT
);
605 return PTR_ERR_OR_ZERO(skb
);
608 static int ll_setup(struct hci_uart
*hu
)
611 struct ll_device
*lldev
;
612 struct serdev_device
*serdev
= hu
->serdev
;
618 lldev
= serdev_device_get_drvdata(serdev
);
620 hu
->hdev
->set_bdaddr
= ll_set_bdaddr
;
622 serdev_device_set_flow_control(serdev
, true);
625 /* Reset the Bluetooth device */
626 gpiod_set_value_cansleep(lldev
->enable_gpio
, 0);
628 gpiod_set_value_cansleep(lldev
->enable_gpio
, 1);
629 err
= serdev_device_wait_for_cts(serdev
, true, 200);
631 bt_dev_err(hu
->hdev
, "Failed to get CTS");
635 err
= download_firmware(lldev
);
639 /* Toggle BT_EN and retry */
640 bt_dev_err(hu
->hdev
, "download firmware failed, retrying...");
646 /* Set BD address if one was specified at probe */
647 if (!bacmp(&lldev
->bdaddr
, BDADDR_NONE
)) {
648 /* This means that there was an error getting the BD address
649 * during probe, so mark the device as having a bad address.
651 set_bit(HCI_QUIRK_INVALID_BDADDR
, &hu
->hdev
->quirks
);
652 } else if (bacmp(&lldev
->bdaddr
, BDADDR_ANY
)) {
653 err
= ll_set_bdaddr(hu
->hdev
, &lldev
->bdaddr
);
655 set_bit(HCI_QUIRK_INVALID_BDADDR
, &hu
->hdev
->quirks
);
658 /* Operational speed if any */
660 speed
= hu
->oper_speed
;
661 else if (hu
->proto
->oper_speed
)
662 speed
= hu
->proto
->oper_speed
;
667 __le32 speed_le
= cpu_to_le32(speed
);
670 skb
= __hci_cmd_sync(hu
->hdev
, HCI_VS_UPDATE_UART_HCI_BAUDRATE
,
671 sizeof(speed_le
), &speed_le
,
675 serdev_device_set_baudrate(serdev
, speed
);
682 static const struct hci_uart_proto llp
;
684 static int hci_ti_probe(struct serdev_device
*serdev
)
687 struct ll_device
*lldev
;
688 struct nvmem_cell
*bdaddr_cell
;
689 u32 max_speed
= 3000000;
691 lldev
= devm_kzalloc(&serdev
->dev
, sizeof(struct ll_device
), GFP_KERNEL
);
696 serdev_device_set_drvdata(serdev
, lldev
);
697 lldev
->serdev
= hu
->serdev
= serdev
;
699 lldev
->enable_gpio
= devm_gpiod_get_optional(&serdev
->dev
,
702 if (IS_ERR(lldev
->enable_gpio
))
703 return PTR_ERR(lldev
->enable_gpio
);
705 lldev
->ext_clk
= devm_clk_get(&serdev
->dev
, "ext_clock");
706 if (IS_ERR(lldev
->ext_clk
) && PTR_ERR(lldev
->ext_clk
) != -ENOENT
)
707 return PTR_ERR(lldev
->ext_clk
);
709 of_property_read_u32(serdev
->dev
.of_node
, "max-speed", &max_speed
);
710 hci_uart_set_speeds(hu
, 115200, max_speed
);
712 /* optional BD address from nvram */
713 bdaddr_cell
= nvmem_cell_get(&serdev
->dev
, "bd-address");
714 if (IS_ERR(bdaddr_cell
)) {
715 int err
= PTR_ERR(bdaddr_cell
);
717 if (err
== -EPROBE_DEFER
)
720 /* ENOENT means there is no matching nvmem cell and ENOSYS
721 * means that nvmem is not enabled in the kernel configuration.
723 if (err
!= -ENOENT
&& err
!= -ENOSYS
) {
724 /* If there was some other error, give userspace a
725 * chance to fix the problem instead of failing to load
726 * the driver. Using BDADDR_NONE as a flag that is
727 * tested later in the setup function.
729 dev_warn(&serdev
->dev
,
730 "Failed to get \"bd-address\" nvmem cell (%d)\n",
732 bacpy(&lldev
->bdaddr
, BDADDR_NONE
);
738 bdaddr
= nvmem_cell_read(bdaddr_cell
, &len
);
739 nvmem_cell_put(bdaddr_cell
);
740 if (IS_ERR(bdaddr
)) {
741 dev_err(&serdev
->dev
, "Failed to read nvmem bd-address\n");
742 return PTR_ERR(bdaddr
);
744 if (len
!= sizeof(bdaddr_t
)) {
745 dev_err(&serdev
->dev
, "Invalid nvmem bd-address length\n");
750 /* As per the device tree bindings, the value from nvmem is
751 * expected to be MSB first, but in the kernel it is expected
752 * that bdaddr_t is LSB first.
754 baswap(&lldev
->bdaddr
, bdaddr
);
758 return hci_uart_register_device(hu
, &llp
);
761 static void hci_ti_remove(struct serdev_device
*serdev
)
763 struct ll_device
*lldev
= serdev_device_get_drvdata(serdev
);
765 hci_uart_unregister_device(&lldev
->hu
);
768 static const struct of_device_id hci_ti_of_match
[] = {
769 { .compatible
= "ti,cc2560" },
770 { .compatible
= "ti,wl1271-st" },
771 { .compatible
= "ti,wl1273-st" },
772 { .compatible
= "ti,wl1281-st" },
773 { .compatible
= "ti,wl1283-st" },
774 { .compatible
= "ti,wl1285-st" },
775 { .compatible
= "ti,wl1801-st" },
776 { .compatible
= "ti,wl1805-st" },
777 { .compatible
= "ti,wl1807-st" },
778 { .compatible
= "ti,wl1831-st" },
779 { .compatible
= "ti,wl1835-st" },
780 { .compatible
= "ti,wl1837-st" },
783 MODULE_DEVICE_TABLE(of
, hci_ti_of_match
);
785 static struct serdev_device_driver hci_ti_drv
= {
788 .of_match_table
= of_match_ptr(hci_ti_of_match
),
790 .probe
= hci_ti_probe
,
791 .remove
= hci_ti_remove
,
794 #define ll_setup NULL
797 static const struct hci_uart_proto llp
= {
804 .enqueue
= ll_enqueue
,
805 .dequeue
= ll_dequeue
,
809 int __init
ll_init(void)
811 serdev_device_driver_register(&hci_ti_drv
);
813 return hci_uart_register_proto(&llp
);
816 int __exit
ll_deinit(void)
818 serdev_device_driver_unregister(&hci_ti_drv
);
820 return hci_uart_unregister_proto(&llp
);