xref: /linux/drivers/bluetooth/hci_nokia.c (revision 91ec2035134982b98fab0609a9fd8480e8217dc1)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Bluetooth HCI UART H4 driver with Nokia Extensions AKA Nokia H4+
4  *
5  *  Copyright (C) 2015 Marcel Holtmann <marcel@holtmann.org>
6  *  Copyright (C) 2015-2017 Sebastian Reichel <sre@kernel.org>
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/errno.h>
11 #include <linux/firmware.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/serdev.h>
19 #include <linux/skbuff.h>
20 #include <linux/slab.h>
21 #include <linux/string.h>
22 #include <linux/types.h>
23 #include <linux/unaligned.h>
24 #include <net/bluetooth/bluetooth.h>
25 #include <net/bluetooth/hci_core.h>
26 
27 #include "hci_uart.h"
28 #include "btbcm.h"
29 
30 #define VERSION "0.1"
31 
32 #define NOKIA_ID_BCM2048	0x04
33 #define NOKIA_ID_TI1271		0x31
34 
35 #define FIRMWARE_BCM2048	"nokia/bcmfw.bin"
36 #define FIRMWARE_TI1271		"nokia/ti1273.bin"
37 
38 #define HCI_NOKIA_NEG_PKT	0x06
39 #define HCI_NOKIA_ALIVE_PKT	0x07
40 #define HCI_NOKIA_RADIO_PKT	0x08
41 
42 #define HCI_NOKIA_NEG_HDR_SIZE		1
43 #define HCI_NOKIA_MAX_NEG_SIZE		255
44 #define HCI_NOKIA_ALIVE_HDR_SIZE	1
45 #define HCI_NOKIA_MAX_ALIVE_SIZE	255
46 #define HCI_NOKIA_RADIO_HDR_SIZE	2
47 #define HCI_NOKIA_MAX_RADIO_SIZE	255
48 
49 #define NOKIA_PROTO_PKT		0x44
50 #define NOKIA_PROTO_BYTE	0x4c
51 
52 #define NOKIA_NEG_REQ		0x00
53 #define NOKIA_NEG_ACK		0x20
54 #define NOKIA_NEG_NAK		0x40
55 
56 #define H4_TYPE_SIZE		1
57 
58 #define NOKIA_RECV_ALIVE \
59 	.type = HCI_NOKIA_ALIVE_PKT, \
60 	.hlen = HCI_NOKIA_ALIVE_HDR_SIZE, \
61 	.loff = 0, \
62 	.lsize = 1, \
63 	.maxlen = HCI_NOKIA_MAX_ALIVE_SIZE \
64 
65 #define NOKIA_RECV_NEG \
66 	.type = HCI_NOKIA_NEG_PKT, \
67 	.hlen = HCI_NOKIA_NEG_HDR_SIZE, \
68 	.loff = 0, \
69 	.lsize = 1, \
70 	.maxlen = HCI_NOKIA_MAX_NEG_SIZE \
71 
72 #define NOKIA_RECV_RADIO \
73 	.type = HCI_NOKIA_RADIO_PKT, \
74 	.hlen = HCI_NOKIA_RADIO_HDR_SIZE, \
75 	.loff = 1, \
76 	.lsize = 1, \
77 	.maxlen = HCI_NOKIA_MAX_RADIO_SIZE \
78 
79 struct hci_nokia_neg_hdr {
80 	u8	dlen;
81 } __packed;
82 
83 struct hci_nokia_neg_cmd {
84 	u8	ack;
85 	u16	baud;
86 	u16	unused1;
87 	u8	proto;
88 	u16	sys_clk;
89 	u16	unused2;
90 } __packed;
91 
92 #define NOKIA_ALIVE_REQ   0x55
93 #define NOKIA_ALIVE_RESP  0xcc
94 
95 struct hci_nokia_alive_hdr {
96 	u8	dlen;
97 } __packed;
98 
99 struct hci_nokia_alive_pkt {
100 	u8	mid;
101 	u8	unused;
102 } __packed;
103 
104 struct hci_nokia_neg_evt {
105 	u8	ack;
106 	u16	baud;
107 	u16	unused1;
108 	u8	proto;
109 	u16	sys_clk;
110 	u16	unused2;
111 	u8	man_id;
112 	u8	ver_id;
113 } __packed;
114 
115 #define MAX_BAUD_RATE		3692300
116 #define SETUP_BAUD_RATE		921600
117 #define INIT_BAUD_RATE		120000
118 
119 struct nokia_bt_dev {
120 	struct hci_uart hu;
121 	struct serdev_device *serdev;
122 
123 	struct gpio_desc *reset;
124 	struct gpio_desc *wakeup_host;
125 	struct gpio_desc *wakeup_bt;
126 	unsigned long sysclk_speed;
127 
128 	int wake_irq;
129 	struct sk_buff *rx_skb;
130 	struct sk_buff_head txq;
131 	bdaddr_t bdaddr;
132 
133 	int init_error;
134 	struct completion init_completion;
135 
136 	u8 man_id;
137 	u8 ver_id;
138 
139 	bool initialized;
140 	bool tx_enabled;
141 	bool rx_enabled;
142 };
143 
144 static int nokia_enqueue(struct hci_uart *hu, struct sk_buff *skb);
145 
nokia_flow_control(struct serdev_device * serdev,bool enable)146 static void nokia_flow_control(struct serdev_device *serdev, bool enable)
147 {
148 	if (enable) {
149 		serdev_device_set_rts(serdev, true);
150 		serdev_device_set_flow_control(serdev, true);
151 	} else {
152 		serdev_device_set_flow_control(serdev, false);
153 		serdev_device_set_rts(serdev, false);
154 	}
155 }
156 
wakeup_handler(int irq,void * data)157 static irqreturn_t wakeup_handler(int irq, void *data)
158 {
159 	struct nokia_bt_dev *btdev = data;
160 	struct device *dev = &btdev->serdev->dev;
161 	int wake_state = gpiod_get_value(btdev->wakeup_host);
162 
163 	if (btdev->rx_enabled == wake_state)
164 		return IRQ_HANDLED;
165 
166 	if (wake_state)
167 		pm_runtime_get(dev);
168 	else
169 		pm_runtime_put(dev);
170 
171 	btdev->rx_enabled = wake_state;
172 
173 	return IRQ_HANDLED;
174 }
175 
nokia_reset(struct hci_uart * hu)176 static int nokia_reset(struct hci_uart *hu)
177 {
178 	struct nokia_bt_dev *btdev = hu->priv;
179 	struct device *dev = &btdev->serdev->dev;
180 	int err;
181 
182 	/* reset routine */
183 	gpiod_set_value_cansleep(btdev->reset, 1);
184 	gpiod_set_value_cansleep(btdev->wakeup_bt, 1);
185 
186 	msleep(100);
187 
188 	/* safety check */
189 	err = gpiod_get_value_cansleep(btdev->wakeup_host);
190 	if (err == 1) {
191 		dev_err(dev, "reset: host wakeup not low!");
192 		return -EPROTO;
193 	}
194 
195 	/* flush queue */
196 	serdev_device_write_flush(btdev->serdev);
197 
198 	/* init uart */
199 	nokia_flow_control(btdev->serdev, false);
200 	serdev_device_set_baudrate(btdev->serdev, INIT_BAUD_RATE);
201 
202 	gpiod_set_value_cansleep(btdev->reset, 0);
203 
204 	/* wait for cts */
205 	err = serdev_device_wait_for_cts(btdev->serdev, true, 200);
206 	if (err < 0) {
207 		dev_err(dev, "CTS not received: %d", err);
208 		return err;
209 	}
210 
211 	nokia_flow_control(btdev->serdev, true);
212 
213 	return 0;
214 }
215 
nokia_send_alive_packet(struct hci_uart * hu)216 static int nokia_send_alive_packet(struct hci_uart *hu)
217 {
218 	struct nokia_bt_dev *btdev = hu->priv;
219 	struct device *dev = &btdev->serdev->dev;
220 	struct hci_nokia_alive_hdr *hdr;
221 	struct hci_nokia_alive_pkt *pkt;
222 	struct sk_buff *skb;
223 	int len;
224 
225 	init_completion(&btdev->init_completion);
226 
227 	len = H4_TYPE_SIZE + sizeof(*hdr) + sizeof(*pkt);
228 	skb = bt_skb_alloc(len, GFP_KERNEL);
229 	if (!skb)
230 		return -ENOMEM;
231 
232 	hci_skb_pkt_type(skb) = HCI_NOKIA_ALIVE_PKT;
233 	memset(skb->data, 0x00, len);
234 
235 	hdr = skb_put(skb, sizeof(*hdr));
236 	hdr->dlen = sizeof(*pkt);
237 	pkt = skb_put(skb, sizeof(*pkt));
238 	pkt->mid = NOKIA_ALIVE_REQ;
239 
240 	nokia_enqueue(hu, skb);
241 	hci_uart_tx_wakeup(hu);
242 
243 	dev_dbg(dev, "Alive sent");
244 
245 	if (!wait_for_completion_interruptible_timeout(&btdev->init_completion,
246 		msecs_to_jiffies(1000))) {
247 		return -ETIMEDOUT;
248 	}
249 
250 	if (btdev->init_error < 0)
251 		return btdev->init_error;
252 
253 	return 0;
254 }
255 
nokia_send_negotiation(struct hci_uart * hu)256 static int nokia_send_negotiation(struct hci_uart *hu)
257 {
258 	struct nokia_bt_dev *btdev = hu->priv;
259 	struct device *dev = &btdev->serdev->dev;
260 	struct hci_nokia_neg_cmd *neg_cmd;
261 	struct hci_nokia_neg_hdr *neg_hdr;
262 	struct sk_buff *skb;
263 	int len, err;
264 	u16 baud = DIV_ROUND_CLOSEST(btdev->sysclk_speed * 10, SETUP_BAUD_RATE);
265 	int sysclk = btdev->sysclk_speed / 1000;
266 
267 	len = H4_TYPE_SIZE + sizeof(*neg_hdr) + sizeof(*neg_cmd);
268 	skb = bt_skb_alloc(len, GFP_KERNEL);
269 	if (!skb)
270 		return -ENOMEM;
271 
272 	hci_skb_pkt_type(skb) = HCI_NOKIA_NEG_PKT;
273 
274 	neg_hdr = skb_put(skb, sizeof(*neg_hdr));
275 	neg_hdr->dlen = sizeof(*neg_cmd);
276 
277 	neg_cmd = skb_put(skb, sizeof(*neg_cmd));
278 	neg_cmd->ack = NOKIA_NEG_REQ;
279 	neg_cmd->baud = cpu_to_le16(baud);
280 	neg_cmd->unused1 = 0x0000;
281 	neg_cmd->proto = NOKIA_PROTO_BYTE;
282 	neg_cmd->sys_clk = cpu_to_le16(sysclk);
283 	neg_cmd->unused2 = 0x0000;
284 
285 	btdev->init_error = 0;
286 	init_completion(&btdev->init_completion);
287 
288 	nokia_enqueue(hu, skb);
289 	hci_uart_tx_wakeup(hu);
290 
291 	dev_dbg(dev, "Negotiation sent");
292 
293 	if (!wait_for_completion_interruptible_timeout(&btdev->init_completion,
294 		msecs_to_jiffies(10000))) {
295 		return -ETIMEDOUT;
296 	}
297 
298 	if (btdev->init_error < 0)
299 		return btdev->init_error;
300 
301 	/* Change to previously negotiated speed. Flow Control
302 	 * is disabled until bluetooth adapter is ready to avoid
303 	 * broken bytes being received.
304 	 */
305 	nokia_flow_control(btdev->serdev, false);
306 	serdev_device_set_baudrate(btdev->serdev, SETUP_BAUD_RATE);
307 	err = serdev_device_wait_for_cts(btdev->serdev, true, 200);
308 	if (err < 0) {
309 		dev_err(dev, "CTS not received: %d", err);
310 		return err;
311 	}
312 	nokia_flow_control(btdev->serdev, true);
313 
314 	dev_dbg(dev, "Negotiation successful");
315 
316 	return 0;
317 }
318 
nokia_setup_fw(struct hci_uart * hu)319 static int nokia_setup_fw(struct hci_uart *hu)
320 {
321 	struct nokia_bt_dev *btdev = hu->priv;
322 	struct device *dev = &btdev->serdev->dev;
323 	const char *fwname;
324 	const struct firmware *fw;
325 	const u8 *fw_ptr;
326 	size_t fw_size;
327 	int err;
328 
329 	dev_dbg(dev, "setup firmware");
330 
331 	if (btdev->man_id == NOKIA_ID_BCM2048) {
332 		fwname = FIRMWARE_BCM2048;
333 	} else if (btdev->man_id == NOKIA_ID_TI1271) {
334 		fwname = FIRMWARE_TI1271;
335 	} else {
336 		dev_err(dev, "Unsupported bluetooth device!");
337 		return -ENODEV;
338 	}
339 
340 	err = request_firmware(&fw, fwname, dev);
341 	if (err < 0) {
342 		dev_err(dev, "%s: Failed to load Nokia firmware file (%d)",
343 			hu->hdev->name, err);
344 		return err;
345 	}
346 
347 	fw_ptr = fw->data;
348 	fw_size = fw->size;
349 
350 	while (fw_size >= 4) {
351 		u16 pkt_size = get_unaligned_le16(fw_ptr);
352 		u8 pkt_type = fw_ptr[2];
353 		const struct hci_command_hdr *cmd;
354 		u16 opcode;
355 		struct sk_buff *skb;
356 
357 		if (pkt_size > fw_size - 2) {
358 			err = -EINVAL;
359 			dev_err(dev, "%s: Malformed firmware packet\n",
360 				hu->hdev->name);
361 			goto done;
362 		}
363 
364 		switch (pkt_type) {
365 		case HCI_COMMAND_PKT:
366 			if (pkt_size < 1 + HCI_COMMAND_HDR_SIZE) {
367 				err = -EINVAL;
368 				dev_err(dev, "%s: Malformed firmware command\n",
369 					hu->hdev->name);
370 				goto done;
371 			}
372 
373 			cmd = (struct hci_command_hdr *)(fw_ptr + 3);
374 			if (cmd->plen > pkt_size - 1 - HCI_COMMAND_HDR_SIZE) {
375 				err = -EINVAL;
376 				dev_err(dev, "%s: Truncated firmware command\n",
377 					hu->hdev->name);
378 				goto done;
379 			}
380 			opcode = le16_to_cpu(cmd->opcode);
381 
382 			skb = __hci_cmd_sync(hu->hdev, opcode, cmd->plen,
383 					     fw_ptr + 3 + HCI_COMMAND_HDR_SIZE,
384 					     HCI_INIT_TIMEOUT);
385 			if (IS_ERR(skb)) {
386 				err = PTR_ERR(skb);
387 				dev_err(dev, "%s: FW command %04x failed (%d)",
388 				       hu->hdev->name, opcode, err);
389 				goto done;
390 			}
391 			kfree_skb(skb);
392 			break;
393 		case HCI_NOKIA_RADIO_PKT:
394 		case HCI_NOKIA_NEG_PKT:
395 		case HCI_NOKIA_ALIVE_PKT:
396 			break;
397 		}
398 
399 		fw_ptr += pkt_size + 2;
400 		fw_size -= pkt_size + 2;
401 	}
402 
403 done:
404 	release_firmware(fw);
405 	return err;
406 }
407 
nokia_setup(struct hci_uart * hu)408 static int nokia_setup(struct hci_uart *hu)
409 {
410 	struct nokia_bt_dev *btdev = hu->priv;
411 	struct device *dev = &btdev->serdev->dev;
412 	int err;
413 
414 	btdev->initialized = false;
415 
416 	nokia_flow_control(btdev->serdev, false);
417 
418 	pm_runtime_get_sync(dev);
419 
420 	if (btdev->tx_enabled) {
421 		gpiod_set_value_cansleep(btdev->wakeup_bt, 0);
422 		pm_runtime_put(&btdev->serdev->dev);
423 		btdev->tx_enabled = false;
424 	}
425 
426 	dev_dbg(dev, "protocol setup");
427 
428 	/* 0. reset connection */
429 	err = nokia_reset(hu);
430 	if (err < 0) {
431 		dev_err(dev, "Reset failed: %d", err);
432 		goto out;
433 	}
434 
435 	/* 1. negotiate speed etc */
436 	err = nokia_send_negotiation(hu);
437 	if (err < 0) {
438 		dev_err(dev, "Negotiation failed: %d", err);
439 		goto out;
440 	}
441 
442 	/* 2. verify correct setup using alive packet */
443 	err = nokia_send_alive_packet(hu);
444 	if (err < 0) {
445 		dev_err(dev, "Alive check failed: %d", err);
446 		goto out;
447 	}
448 
449 	/* 3. send firmware */
450 	err = nokia_setup_fw(hu);
451 	if (err < 0) {
452 		dev_err(dev, "Could not setup FW: %d", err);
453 		goto out;
454 	}
455 
456 	nokia_flow_control(btdev->serdev, false);
457 	serdev_device_set_baudrate(btdev->serdev, MAX_BAUD_RATE);
458 	nokia_flow_control(btdev->serdev, true);
459 
460 	if (btdev->man_id == NOKIA_ID_BCM2048) {
461 		hu->hdev->set_bdaddr = btbcm_set_bdaddr;
462 		hci_set_quirk(hu->hdev, HCI_QUIRK_INVALID_BDADDR);
463 		dev_dbg(dev, "bcm2048 has invalid bluetooth address!");
464 	}
465 
466 	dev_dbg(dev, "protocol setup done!");
467 
468 	gpiod_set_value_cansleep(btdev->wakeup_bt, 0);
469 	pm_runtime_put(dev);
470 	btdev->tx_enabled = false;
471 	btdev->initialized = true;
472 
473 	return 0;
474 out:
475 	pm_runtime_put(dev);
476 
477 	return err;
478 }
479 
nokia_open(struct hci_uart * hu)480 static int nokia_open(struct hci_uart *hu)
481 {
482 	struct device *dev = &hu->serdev->dev;
483 
484 	dev_dbg(dev, "protocol open");
485 
486 	pm_runtime_enable(dev);
487 
488 	return 0;
489 }
490 
nokia_flush(struct hci_uart * hu)491 static int nokia_flush(struct hci_uart *hu)
492 {
493 	struct nokia_bt_dev *btdev = hu->priv;
494 
495 	dev_dbg(&btdev->serdev->dev, "flush device");
496 
497 	skb_queue_purge(&btdev->txq);
498 
499 	return 0;
500 }
501 
nokia_close(struct hci_uart * hu)502 static int nokia_close(struct hci_uart *hu)
503 {
504 	struct nokia_bt_dev *btdev = hu->priv;
505 	struct device *dev = &btdev->serdev->dev;
506 
507 	dev_dbg(dev, "close device");
508 
509 	btdev->initialized = false;
510 
511 	skb_queue_purge(&btdev->txq);
512 
513 	kfree_skb(btdev->rx_skb);
514 
515 	/* disable module */
516 	gpiod_set_value(btdev->reset, 1);
517 	gpiod_set_value(btdev->wakeup_bt, 0);
518 
519 	pm_runtime_disable(&btdev->serdev->dev);
520 
521 	return 0;
522 }
523 
524 /* Enqueue frame for transmission (padding, crc, etc) */
nokia_enqueue(struct hci_uart * hu,struct sk_buff * skb)525 static int nokia_enqueue(struct hci_uart *hu, struct sk_buff *skb)
526 {
527 	struct nokia_bt_dev *btdev = hu->priv;
528 	int err;
529 
530 	/* Prepend skb with frame type */
531 	memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
532 
533 	/* Packets must be word aligned */
534 	if (skb->len % 2) {
535 		err = skb_pad(skb, 1);
536 		if (err)
537 			return err;
538 		skb_put(skb, 1);
539 	}
540 
541 	skb_queue_tail(&btdev->txq, skb);
542 
543 	return 0;
544 }
545 
nokia_recv_negotiation_packet(struct hci_dev * hdev,struct sk_buff * skb)546 static int nokia_recv_negotiation_packet(struct hci_dev *hdev,
547 					 struct sk_buff *skb)
548 {
549 	struct hci_uart *hu = hci_get_drvdata(hdev);
550 	struct nokia_bt_dev *btdev = hu->priv;
551 	struct device *dev = &btdev->serdev->dev;
552 	struct hci_nokia_neg_hdr *hdr;
553 	struct hci_nokia_neg_evt *evt;
554 	int ret = 0;
555 
556 	hdr = (struct hci_nokia_neg_hdr *)skb->data;
557 	if (hdr->dlen != sizeof(*evt)) {
558 		btdev->init_error = -EIO;
559 		ret = -EIO;
560 		goto finish_neg;
561 	}
562 
563 	evt = skb_pull(skb, sizeof(*hdr));
564 
565 	if (evt->ack != NOKIA_NEG_ACK) {
566 		dev_err(dev, "Negotiation received: wrong reply");
567 		btdev->init_error = -EINVAL;
568 		ret = -EINVAL;
569 		goto finish_neg;
570 	}
571 
572 	btdev->man_id = evt->man_id;
573 	btdev->ver_id = evt->ver_id;
574 
575 	dev_dbg(dev, "Negotiation received: baud=%u:clk=%u:manu=%u:vers=%u",
576 		evt->baud, evt->sys_clk, evt->man_id, evt->ver_id);
577 
578 finish_neg:
579 	complete(&btdev->init_completion);
580 	kfree_skb(skb);
581 	return ret;
582 }
583 
nokia_recv_alive_packet(struct hci_dev * hdev,struct sk_buff * skb)584 static int nokia_recv_alive_packet(struct hci_dev *hdev, struct sk_buff *skb)
585 {
586 	struct hci_uart *hu = hci_get_drvdata(hdev);
587 	struct nokia_bt_dev *btdev = hu->priv;
588 	struct device *dev = &btdev->serdev->dev;
589 	struct hci_nokia_alive_hdr *hdr;
590 	struct hci_nokia_alive_pkt *pkt;
591 	int ret = 0;
592 
593 	hdr = (struct hci_nokia_alive_hdr *)skb->data;
594 	if (hdr->dlen != sizeof(*pkt)) {
595 		dev_err(dev, "Corrupted alive message");
596 		btdev->init_error = -EIO;
597 		ret = -EIO;
598 		goto finish_alive;
599 	}
600 
601 	pkt = skb_pull(skb, sizeof(*hdr));
602 
603 	if (pkt->mid != NOKIA_ALIVE_RESP) {
604 		dev_err(dev, "Alive received: invalid response: 0x%02x!",
605 			pkt->mid);
606 		btdev->init_error = -EINVAL;
607 		ret = -EINVAL;
608 		goto finish_alive;
609 	}
610 
611 	dev_dbg(dev, "Alive received");
612 
613 finish_alive:
614 	complete(&btdev->init_completion);
615 	kfree_skb(skb);
616 	return ret;
617 }
618 
nokia_recv_radio(struct hci_dev * hdev,struct sk_buff * skb)619 static int nokia_recv_radio(struct hci_dev *hdev, struct sk_buff *skb)
620 {
621 	/* Packets received on the dedicated radio channel are
622 	 * HCI events and so feed them back into the core.
623 	 */
624 	hci_skb_pkt_type(skb) = HCI_EVENT_PKT;
625 	return hci_recv_frame(hdev, skb);
626 }
627 
628 /* Recv data */
629 static const struct h4_recv_pkt nokia_recv_pkts[] = {
630 	{ H4_RECV_ACL,		.recv = hci_recv_frame },
631 	{ H4_RECV_SCO,		.recv = hci_recv_frame },
632 	{ H4_RECV_EVENT,	.recv = hci_recv_frame },
633 	{ NOKIA_RECV_ALIVE,	.recv = nokia_recv_alive_packet },
634 	{ NOKIA_RECV_NEG,	.recv = nokia_recv_negotiation_packet },
635 	{ NOKIA_RECV_RADIO,	.recv = nokia_recv_radio },
636 };
637 
nokia_recv(struct hci_uart * hu,const void * data,int count)638 static int nokia_recv(struct hci_uart *hu, const void *data, int count)
639 {
640 	struct nokia_bt_dev *btdev = hu->priv;
641 	struct device *dev = &btdev->serdev->dev;
642 	int err;
643 
644 	if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
645 		return -EUNATCH;
646 
647 	btdev->rx_skb = h4_recv_buf(hu, btdev->rx_skb, data, count,
648 				    nokia_recv_pkts, ARRAY_SIZE(nokia_recv_pkts));
649 	if (IS_ERR(btdev->rx_skb)) {
650 		err = PTR_ERR(btdev->rx_skb);
651 		dev_err(dev, "Frame reassembly failed (%d)", err);
652 		btdev->rx_skb = NULL;
653 		return err;
654 	}
655 
656 	return count;
657 }
658 
nokia_dequeue(struct hci_uart * hu)659 static struct sk_buff *nokia_dequeue(struct hci_uart *hu)
660 {
661 	struct nokia_bt_dev *btdev = hu->priv;
662 	struct device *dev = &btdev->serdev->dev;
663 	struct sk_buff *result = skb_dequeue(&btdev->txq);
664 
665 	if (!btdev->initialized)
666 		return result;
667 
668 	if (btdev->tx_enabled == !!result)
669 		return result;
670 
671 	if (result) {
672 		pm_runtime_get_sync(dev);
673 		gpiod_set_value_cansleep(btdev->wakeup_bt, 1);
674 	} else {
675 		serdev_device_wait_until_sent(btdev->serdev, 0);
676 		gpiod_set_value_cansleep(btdev->wakeup_bt, 0);
677 		pm_runtime_put(dev);
678 	}
679 
680 	btdev->tx_enabled = !!result;
681 
682 	return result;
683 }
684 
685 static const struct hci_uart_proto nokia_proto = {
686 	.id		= HCI_UART_NOKIA,
687 	.name		= "Nokia",
688 	.open		= nokia_open,
689 	.close		= nokia_close,
690 	.recv		= nokia_recv,
691 	.enqueue	= nokia_enqueue,
692 	.dequeue	= nokia_dequeue,
693 	.flush		= nokia_flush,
694 	.setup		= nokia_setup,
695 	.manufacturer	= 1,
696 };
697 
nokia_bluetooth_serdev_probe(struct serdev_device * serdev)698 static int nokia_bluetooth_serdev_probe(struct serdev_device *serdev)
699 {
700 	struct device *dev = &serdev->dev;
701 	struct nokia_bt_dev *btdev;
702 	struct clk *sysclk;
703 	int err = 0;
704 
705 	btdev = devm_kzalloc(dev, sizeof(*btdev), GFP_KERNEL);
706 	if (!btdev)
707 		return -ENOMEM;
708 
709 	btdev->hu.serdev = btdev->serdev = serdev;
710 	serdev_device_set_drvdata(serdev, btdev);
711 
712 	btdev->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
713 	if (IS_ERR(btdev->reset)) {
714 		err = PTR_ERR(btdev->reset);
715 		dev_err(dev, "could not get reset gpio: %d", err);
716 		return err;
717 	}
718 
719 	btdev->wakeup_host = devm_gpiod_get(dev, "host-wakeup", GPIOD_IN);
720 	if (IS_ERR(btdev->wakeup_host)) {
721 		err = PTR_ERR(btdev->wakeup_host);
722 		dev_err(dev, "could not get host wakeup gpio: %d", err);
723 		return err;
724 	}
725 
726 	btdev->wake_irq = gpiod_to_irq(btdev->wakeup_host);
727 
728 	err = devm_request_threaded_irq(dev, btdev->wake_irq, NULL,
729 		wakeup_handler,
730 		IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
731 		"wakeup", btdev);
732 	if (err) {
733 		dev_err(dev, "could request wakeup irq: %d", err);
734 		return err;
735 	}
736 
737 	btdev->wakeup_bt = devm_gpiod_get(dev, "bluetooth-wakeup",
738 					   GPIOD_OUT_LOW);
739 	if (IS_ERR(btdev->wakeup_bt)) {
740 		err = PTR_ERR(btdev->wakeup_bt);
741 		dev_err(dev, "could not get BT wakeup gpio: %d", err);
742 		return err;
743 	}
744 
745 	sysclk = devm_clk_get(dev, "sysclk");
746 	if (IS_ERR(sysclk)) {
747 		err = PTR_ERR(sysclk);
748 		dev_err(dev, "could not get sysclk: %d", err);
749 		return err;
750 	}
751 
752 	err = clk_prepare_enable(sysclk);
753 	if (err) {
754 		dev_err(dev, "could not enable sysclk: %d", err);
755 		return err;
756 	}
757 	btdev->sysclk_speed = clk_get_rate(sysclk);
758 	clk_disable_unprepare(sysclk);
759 
760 	skb_queue_head_init(&btdev->txq);
761 
762 	btdev->hu.priv = btdev;
763 	btdev->hu.alignment = 2; /* Nokia H4+ is word aligned */
764 
765 	err = hci_uart_register_device(&btdev->hu, &nokia_proto);
766 	if (err) {
767 		dev_err(dev, "could not register bluetooth uart: %d", err);
768 		return err;
769 	}
770 
771 	return 0;
772 }
773 
nokia_bluetooth_serdev_remove(struct serdev_device * serdev)774 static void nokia_bluetooth_serdev_remove(struct serdev_device *serdev)
775 {
776 	struct nokia_bt_dev *btdev = serdev_device_get_drvdata(serdev);
777 
778 	hci_uart_unregister_device(&btdev->hu);
779 }
780 
nokia_bluetooth_runtime_suspend(struct device * dev)781 static int nokia_bluetooth_runtime_suspend(struct device *dev)
782 {
783 	struct serdev_device *serdev = to_serdev_device(dev);
784 
785 	nokia_flow_control(serdev, false);
786 	return 0;
787 }
788 
nokia_bluetooth_runtime_resume(struct device * dev)789 static int nokia_bluetooth_runtime_resume(struct device *dev)
790 {
791 	struct serdev_device *serdev = to_serdev_device(dev);
792 
793 	nokia_flow_control(serdev, true);
794 	return 0;
795 }
796 
797 static const struct dev_pm_ops nokia_bluetooth_pm_ops = {
798 	SET_RUNTIME_PM_OPS(nokia_bluetooth_runtime_suspend,
799 			   nokia_bluetooth_runtime_resume,
800 			   NULL)
801 };
802 
803 #ifdef CONFIG_OF
804 static const struct of_device_id nokia_bluetooth_of_match[] = {
805 	{ .compatible = "nokia,h4p-bluetooth", },
806 	{},
807 };
808 MODULE_DEVICE_TABLE(of, nokia_bluetooth_of_match);
809 #endif
810 
811 static struct serdev_device_driver nokia_bluetooth_serdev_driver = {
812 	.probe = nokia_bluetooth_serdev_probe,
813 	.remove = nokia_bluetooth_serdev_remove,
814 	.driver = {
815 		.name = "nokia-bluetooth",
816 		.pm = &nokia_bluetooth_pm_ops,
817 		.of_match_table = of_match_ptr(nokia_bluetooth_of_match),
818 	},
819 };
820 
821 module_serdev_device_driver(nokia_bluetooth_serdev_driver);
822 
823 MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");
824 MODULE_DESCRIPTION("Bluetooth HCI UART Nokia H4+ driver ver " VERSION);
825 MODULE_VERSION(VERSION);
826 MODULE_LICENSE("GPL");
827