btmtkuart.c

  1// SPDX-License-Identifier: GPL-2.0
  2// Copyright (c) 2018 MediaTek Inc.
  3
  4/*
  5 * Bluetooth support for MediaTek serial devices
  6 *
  7 * Author: Sean Wang <sean.wang@mediatek.com>
  8 *
  9 */
 10
 11#include <linux/unaligned.h>
 12#include <linux/atomic.h>
 13#include <linux/clk.h>
 14#include <linux/firmware.h>
 15#include <linux/gpio/consumer.h>
 16#include <linux/iopoll.h>
 17#include <linux/kernel.h>
 18#include <linux/module.h>
 19#include <linux/of.h>
 20#include <linux/pinctrl/consumer.h>
 21#include <linux/pm_runtime.h>
 22#include <linux/regulator/consumer.h>
 23#include <linux/serdev.h>
 24#include <linux/skbuff.h>
 25#include <linux/usb.h>
 26
 27#include <net/bluetooth/bluetooth.h>
 28#include <net/bluetooth/hci_core.h>
 29
 30#include "hci_uart.h"
 31#include "btmtk.h"
 32
 33#define VERSION "0.2"
 34
 35#define MTK_STP_TLR_SIZE	2
 36
 37#define BTMTKUART_TX_STATE_ACTIVE	1
 38#define BTMTKUART_TX_STATE_WAKEUP	2
 39#define BTMTKUART_TX_WAIT_VND_EVT	3
 40#define BTMTKUART_REQUIRED_WAKEUP	4
 41
 42#define BTMTKUART_FLAG_STANDALONE_HW	 BIT(0)
 43
 44struct mtk_stp_hdr {
 45	u8	prefix;
 46	__be16	dlen;
 47	u8	cs;
 48} __packed;
 49
 50struct btmtkuart_data {
 51	unsigned int flags;
 52	const char *fwname;
 53};
 54
 55struct btmtkuart_dev {
 56	struct hci_dev *hdev;
 57	struct serdev_device *serdev;
 58
 59	struct clk *clk;
 60	struct clk *osc;
 61	struct regulator *vcc;
 62	struct gpio_desc *reset;
 63	struct gpio_desc *boot;
 64	struct pinctrl *pinctrl;
 65	struct pinctrl_state *pins_runtime;
 66	struct pinctrl_state *pins_boot;
 67	speed_t	desired_speed;
 68	speed_t	curr_speed;
 69
 70	struct work_struct tx_work;
 71	unsigned long tx_state;
 72	struct sk_buff_head txq;
 73
 74	struct sk_buff *rx_skb;
 75	struct sk_buff *evt_skb;
 76
 77	u8	stp_pad[6];
 78	u8	stp_cursor;
 79	u16	stp_dlen;
 80
 81	const struct btmtkuart_data *data;
 82	struct hci_uart hu;
 83};
 84
 85#define btmtkuart_is_standalone(bdev)	\
 86	((bdev)->data->flags & BTMTKUART_FLAG_STANDALONE_HW)
 87#define btmtkuart_is_builtin_soc(bdev)	\
 88	!((bdev)->data->flags & BTMTKUART_FLAG_STANDALONE_HW)
 89
 90static int mtk_hci_wmt_sync(struct hci_dev *hdev,
 91			    struct btmtk_hci_wmt_params *wmt_params)
 92{
 93	struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 94	struct btmtk_hci_wmt_evt_funcc *wmt_evt_funcc;
 95	u32 hlen, status = BTMTK_WMT_INVALID;
 96	struct btmtk_hci_wmt_evt *wmt_evt;
 97	struct btmtk_hci_wmt_cmd *wc;
 98	struct btmtk_wmt_hdr *hdr;
 99	int err;
100
101	/* Send the WMT command and wait until the WMT event returns */
102	hlen = sizeof(*hdr) + wmt_params->dlen;
103	if (hlen > 255) {
104		err = -EINVAL;
105		goto err_free_skb;
106	}
107
108	wc = kzalloc(hlen, GFP_KERNEL);
109	if (!wc) {
110		err = -ENOMEM;
111		goto err_free_skb;
112	}
113
114	hdr = &wc->hdr;
115	hdr->dir = 1;
116	hdr->op = wmt_params->op;
117	hdr->dlen = cpu_to_le16(wmt_params->dlen + 1);
118	hdr->flag = wmt_params->flag;
119	memcpy(wc->data, wmt_params->data, wmt_params->dlen);
120
121	set_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
122
123	err = __hci_cmd_send(hdev, 0xfc6f, hlen, wc);
124	if (err < 0) {
125		clear_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
126		goto err_free_wc;
127	}
128
129	/* The vendor specific WMT commands are all answered by a vendor
130	 * specific event and will not have the Command Status or Command
131	 * Complete as with usual HCI command flow control.
132	 *
133	 * After sending the command, wait for BTMTKUART_TX_WAIT_VND_EVT
134	 * state to be cleared. The driver specific event receive routine
135	 * will clear that state and with that indicate completion of the
136	 * WMT command.
137	 */
138	err = wait_on_bit_timeout(&bdev->tx_state, BTMTKUART_TX_WAIT_VND_EVT,
139				  TASK_INTERRUPTIBLE, HCI_INIT_TIMEOUT);
140	if (err == -EINTR) {
141		bt_dev_err(hdev, "Execution of wmt command interrupted");
142		clear_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
143		goto err_free_wc;
144	}
145
146	if (err) {
147		bt_dev_err(hdev, "Execution of wmt command timed out");
148		clear_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
149		err = -ETIMEDOUT;
150		goto err_free_wc;
151	}
152
153	/* Parse and handle the return WMT event */
154	wmt_evt = (struct btmtk_hci_wmt_evt *)bdev->evt_skb->data;
155	if (wmt_evt->whdr.op != hdr->op) {
156		bt_dev_err(hdev, "Wrong op received %d expected %d",
157			   wmt_evt->whdr.op, hdr->op);
158		err = -EIO;
159		goto err_free_wc;
160	}
161
162	switch (wmt_evt->whdr.op) {
163	case BTMTK_WMT_SEMAPHORE:
164		if (wmt_evt->whdr.flag == 2)
165			status = BTMTK_WMT_PATCH_UNDONE;
166		else
167			status = BTMTK_WMT_PATCH_DONE;
168		break;
169	case BTMTK_WMT_FUNC_CTRL:
170		wmt_evt_funcc = (struct btmtk_hci_wmt_evt_funcc *)wmt_evt;
171		if (be16_to_cpu(wmt_evt_funcc->status) == 0x404)
172			status = BTMTK_WMT_ON_DONE;
173		else if (be16_to_cpu(wmt_evt_funcc->status) == 0x420)
174			status = BTMTK_WMT_ON_PROGRESS;
175		else
176			status = BTMTK_WMT_ON_UNDONE;
177		break;
178	}
179
180	if (wmt_params->status)
181		*wmt_params->status = status;
182
183err_free_wc:
184	kfree(wc);
185err_free_skb:
186	kfree_skb(bdev->evt_skb);
187	bdev->evt_skb = NULL;
188
189	return err;
190}
191
192static int btmtkuart_recv_event(struct hci_dev *hdev, struct sk_buff *skb)
193{
194	struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
195	struct hci_event_hdr *hdr = (void *)skb->data;
196	int err;
197
198	/* When someone waits for the WMT event, the skb is being cloned
199	 * and being processed the events from there then.
200	 */
201	if (test_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state)) {
202		bdev->evt_skb = skb_clone(skb, GFP_KERNEL);
203		if (!bdev->evt_skb) {
204			err = -ENOMEM;
205			goto err_out;
206		}
207	}
208
209	err = hci_recv_frame(hdev, skb);
210	if (err < 0)
211		goto err_free_skb;
212
213	if (hdr->evt == HCI_EV_WMT) {
214		if (test_and_clear_bit(BTMTKUART_TX_WAIT_VND_EVT,
215				       &bdev->tx_state)) {
216			/* Barrier to sync with other CPUs */
217			smp_mb__after_atomic();
218			wake_up_bit(&bdev->tx_state, BTMTKUART_TX_WAIT_VND_EVT);
219		}
220	}
221
222	return 0;
223
224err_free_skb:
225	kfree_skb(bdev->evt_skb);
226	bdev->evt_skb = NULL;
227
228err_out:
229	return err;
230}
231
232static const struct h4_recv_pkt mtk_recv_pkts[] = {
233	{ H4_RECV_ACL,      .recv = hci_recv_frame },
234	{ H4_RECV_SCO,      .recv = hci_recv_frame },
235	{ H4_RECV_EVENT,    .recv = btmtkuart_recv_event },
236};
237
238static void btmtkuart_tx_work(struct work_struct *work)
239{
240	struct btmtkuart_dev *bdev = container_of(work, struct btmtkuart_dev,
241						   tx_work);
242	struct serdev_device *serdev = bdev->serdev;
243	struct hci_dev *hdev = bdev->hdev;
244
245	while (1) {
246		clear_bit(BTMTKUART_TX_STATE_WAKEUP, &bdev->tx_state);
247
248		while (1) {
249			struct sk_buff *skb = skb_dequeue(&bdev->txq);
250			int len;
251
252			if (!skb)
253				break;
254
255			len = serdev_device_write_buf(serdev, skb->data,
256						      skb->len);
257			hdev->stat.byte_tx += len;
258
259			skb_pull(skb, len);
260			if (skb->len > 0) {
261				skb_queue_head(&bdev->txq, skb);
262				break;
263			}
264
265			switch (hci_skb_pkt_type(skb)) {
266			case HCI_COMMAND_PKT:
267				hdev->stat.cmd_tx++;
268				break;
269			case HCI_ACLDATA_PKT:
270				hdev->stat.acl_tx++;
271				break;
272			case HCI_SCODATA_PKT:
273				hdev->stat.sco_tx++;
274				break;
275			}
276
277			kfree_skb(skb);
278		}
279
280		if (!test_bit(BTMTKUART_TX_STATE_WAKEUP, &bdev->tx_state))
281			break;
282	}
283
284	clear_bit(BTMTKUART_TX_STATE_ACTIVE, &bdev->tx_state);
285}
286
287static void btmtkuart_tx_wakeup(struct btmtkuart_dev *bdev)
288{
289	if (test_and_set_bit(BTMTKUART_TX_STATE_ACTIVE, &bdev->tx_state))
290		set_bit(BTMTKUART_TX_STATE_WAKEUP, &bdev->tx_state);
291
292	schedule_work(&bdev->tx_work);
293}
294
295static const unsigned char *
296mtk_stp_split(struct btmtkuart_dev *bdev, const unsigned char *data, int count,
297	      int *sz_h4)
298{
299	struct mtk_stp_hdr *shdr;
300
301	/* The cursor is reset when all the data of STP is consumed out */
302	if (!bdev->stp_dlen && bdev->stp_cursor >= 6)
303		bdev->stp_cursor = 0;
304
305	/* Filling pad until all STP info is obtained */
306	while (bdev->stp_cursor < 6 && count > 0) {
307		bdev->stp_pad[bdev->stp_cursor] = *data;
308		bdev->stp_cursor++;
309		data++;
310		count--;
311	}
312
313	/* Retrieve STP info and have a sanity check */
314	if (!bdev->stp_dlen && bdev->stp_cursor >= 6) {
315		shdr = (struct mtk_stp_hdr *)&bdev->stp_pad[2];
316		bdev->stp_dlen = be16_to_cpu(shdr->dlen) & 0x0fff;
317
318		/* Resync STP when unexpected data is being read */
319		if (shdr->prefix != 0x80 || bdev->stp_dlen > 2048) {
320			bt_dev_err(bdev->hdev, "stp format unexpected (%d, %d)",
321				   shdr->prefix, bdev->stp_dlen);
322			bdev->stp_cursor = 2;
323			bdev->stp_dlen = 0;
324		}
325	}
326
327	/* Directly quit when there's no data found for H4 can process */
328	if (count <= 0)
329		return NULL;
330
331	/* Translate to how much the size of data H4 can handle so far */
332	*sz_h4 = min_t(int, count, bdev->stp_dlen);
333
334	/* Update the remaining size of STP packet */
335	bdev->stp_dlen -= *sz_h4;
336
337	/* Data points to STP payload which can be handled by H4 */
338	return data;
339}
340
341static void btmtkuart_recv(struct hci_dev *hdev, const u8 *data, size_t count)
342{
343	struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
344	const unsigned char *p_left = data, *p_h4;
345	int sz_left = count, sz_h4, adv;
346	int err;
347
348	while (sz_left > 0) {
349		/*  The serial data received from MT7622 BT controller is
350		 *  at all time padded around with the STP header and tailer.
351		 *
352		 *  A full STP packet is looking like
353		 *   -----------------------------------
354		 *  | STP header  |  H:4   | STP tailer |
355		 *   -----------------------------------
356		 *  but it doesn't guarantee to contain a full H:4 packet which
357		 *  means that it's possible for multiple STP packets forms a
358		 *  full H:4 packet that means extra STP header + length doesn't
359		 *  indicate a full H:4 frame, things can fragment. Whose length
360		 *  recorded in STP header just shows up the most length the
361		 *  H:4 engine can handle currently.
362		 */
363
364		p_h4 = mtk_stp_split(bdev, p_left, sz_left, &sz_h4);
365		if (!p_h4)
366			break;
367
368		adv = p_h4 - p_left;
369		sz_left -= adv;
370		p_left += adv;
371
372		bdev->rx_skb = h4_recv_buf(&bdev->hu, bdev->rx_skb, p_h4,
373					   sz_h4, mtk_recv_pkts,
374					   ARRAY_SIZE(mtk_recv_pkts));
375		if (IS_ERR(bdev->rx_skb)) {
376			err = PTR_ERR(bdev->rx_skb);
377			bt_dev_err(bdev->hdev,
378				   "Frame reassembly failed (%d)", err);
379			bdev->rx_skb = NULL;
380			return;
381		}
382
383		sz_left -= sz_h4;
384		p_left += sz_h4;
385	}
386}
387
388static size_t btmtkuart_receive_buf(struct serdev_device *serdev,
389				    const u8 *data, size_t count)
390{
391	struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
392
393	btmtkuart_recv(bdev->hdev, data, count);
394
395	bdev->hdev->stat.byte_rx += count;
396
397	return count;
398}
399
400static void btmtkuart_write_wakeup(struct serdev_device *serdev)
401{
402	struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
403
404	btmtkuart_tx_wakeup(bdev);
405}
406
407static const struct serdev_device_ops btmtkuart_client_ops = {
408	.receive_buf = btmtkuart_receive_buf,
409	.write_wakeup = btmtkuart_write_wakeup,
410};
411
412static int btmtkuart_open(struct hci_dev *hdev)
413{
414	struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
415	struct device *dev;
416	int err;
417
418	err = serdev_device_open(bdev->serdev);
419	if (err) {
420		bt_dev_err(hdev, "Unable to open UART device %s",
421			   dev_name(&bdev->serdev->dev));
422		goto err_open;
423	}
424
425	if (btmtkuart_is_standalone(bdev)) {
426		if (bdev->curr_speed != bdev->desired_speed)
427			err = serdev_device_set_baudrate(bdev->serdev,
428							 115200);
429		else
430			err = serdev_device_set_baudrate(bdev->serdev,
431							 bdev->desired_speed);
432
433		if (err < 0) {
434			bt_dev_err(hdev, "Unable to set baudrate UART device %s",
435				   dev_name(&bdev->serdev->dev));
436			goto  err_serdev_close;
437		}
438
439		serdev_device_set_flow_control(bdev->serdev, false);
440	}
441
442	bdev->stp_cursor = 2;
443	bdev->stp_dlen = 0;
444
445	dev = &bdev->serdev->dev;
446
447	/* Enable the power domain and clock the device requires */
448	pm_runtime_enable(dev);
449	err = pm_runtime_resume_and_get(dev);
450	if (err < 0)
451		goto err_disable_rpm;
452
453	err = clk_prepare_enable(bdev->clk);
454	if (err < 0)
455		goto err_put_rpm;
456
457	return 0;
458
459err_put_rpm:
460	pm_runtime_put_sync(dev);
461err_disable_rpm:
462	pm_runtime_disable(dev);
463err_serdev_close:
464	serdev_device_close(bdev->serdev);
465err_open:
466	return err;
467}
468
469static int btmtkuart_close(struct hci_dev *hdev)
470{
471	struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
472	struct device *dev = &bdev->serdev->dev;
473
474	/* Shutdown the clock and power domain the device requires */
475	clk_disable_unprepare(bdev->clk);
476	pm_runtime_put_sync(dev);
477	pm_runtime_disable(dev);
478
479	serdev_device_close(bdev->serdev);
480
481	return 0;
482}
483
484static int btmtkuart_flush(struct hci_dev *hdev)
485{
486	struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
487
488	/* Flush any pending characters */
489	serdev_device_write_flush(bdev->serdev);
490	skb_queue_purge(&bdev->txq);
491
492	cancel_work_sync(&bdev->tx_work);
493
494	kfree_skb(bdev->rx_skb);
495	bdev->rx_skb = NULL;
496
497	bdev->stp_cursor = 2;
498	bdev->stp_dlen = 0;
499
500	return 0;
501}
502
503static int btmtkuart_func_query(struct hci_dev *hdev)
504{
505	struct btmtk_hci_wmt_params wmt_params;
506	int status, err;
507	u8 param = 0;
508
509	/* Query whether the function is enabled */
510	wmt_params.op = BTMTK_WMT_FUNC_CTRL;
511	wmt_params.flag = 4;
512	wmt_params.dlen = sizeof(param);
513	wmt_params.data = &param;
514	wmt_params.status = &status;
515
516	err = mtk_hci_wmt_sync(hdev, &wmt_params);
517	if (err < 0) {
518		bt_dev_err(hdev, "Failed to query function status (%d)", err);
519		return err;
520	}
521
522	return status;
523}
524
525static int btmtkuart_change_baudrate(struct hci_dev *hdev)
526{
527	struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
528	struct btmtk_hci_wmt_params wmt_params;
529	__le32 baudrate;
530	u8 param;
531	int err;
532
533	/* Indicate the device to enter the probe state the host is
534	 * ready to change a new baudrate.
535	 */
536	baudrate = cpu_to_le32(bdev->desired_speed);
537	wmt_params.op = BTMTK_WMT_HIF;
538	wmt_params.flag = 1;
539	wmt_params.dlen = 4;
540	wmt_params.data = &baudrate;
541	wmt_params.status = NULL;
542
543	err = mtk_hci_wmt_sync(hdev, &wmt_params);
544	if (err < 0) {
545		bt_dev_err(hdev, "Failed to device baudrate (%d)", err);
546		return err;
547	}
548
549	err = serdev_device_set_baudrate(bdev->serdev,
550					 bdev->desired_speed);
551	if (err < 0) {
552		bt_dev_err(hdev, "Failed to set up host baudrate (%d)",
553			   err);
554		return err;
555	}
556
557	serdev_device_set_flow_control(bdev->serdev, false);
558
559	/* Send a dummy byte 0xff to activate the new baudrate */
560	param = 0xff;
561	err = serdev_device_write_buf(bdev->serdev, &param, sizeof(param));
562	if (err < 0 || err < sizeof(param))
563		return err;
564
565	serdev_device_wait_until_sent(bdev->serdev, 0);
566
567	/* Wait some time for the device changing baudrate done */
568	usleep_range(20000, 22000);
569
570	/* Test the new baudrate */
571	wmt_params.op = BTMTK_WMT_TEST;
572	wmt_params.flag = 7;
573	wmt_params.dlen = 0;
574	wmt_params.data = NULL;
575	wmt_params.status = NULL;
576
577	err = mtk_hci_wmt_sync(hdev, &wmt_params);
578	if (err < 0) {
579		bt_dev_err(hdev, "Failed to test new baudrate (%d)",
580			   err);
581		return err;
582	}
583
584	bdev->curr_speed = bdev->desired_speed;
585
586	return 0;
587}
588
589static int btmtkuart_setup(struct hci_dev *hdev)
590{
591	struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
592	struct btmtk_hci_wmt_params wmt_params;
593	ktime_t calltime, delta, rettime;
594	struct btmtk_tci_sleep tci_sleep;
595	unsigned long long duration;
596	struct sk_buff *skb;
597	int err, status;
598	u8 param = 0x1;
599
600	calltime = ktime_get();
601
602	/* Wakeup MCUSYS is required for certain devices before we start to
603	 * do any setups.
604	 */
605	if (test_bit(BTMTKUART_REQUIRED_WAKEUP, &bdev->tx_state)) {
606		wmt_params.op = BTMTK_WMT_WAKEUP;
607		wmt_params.flag = 3;
608		wmt_params.dlen = 0;
609		wmt_params.data = NULL;
610		wmt_params.status = NULL;
611
612		err = mtk_hci_wmt_sync(hdev, &wmt_params);
613		if (err < 0) {
614			bt_dev_err(hdev, "Failed to wakeup the chip (%d)", err);
615			return err;
616		}
617
618		clear_bit(BTMTKUART_REQUIRED_WAKEUP, &bdev->tx_state);
619	}
620
621	if (btmtkuart_is_standalone(bdev))
622		btmtkuart_change_baudrate(hdev);
623
624	/* Query whether the firmware is already download */
625	wmt_params.op = BTMTK_WMT_SEMAPHORE;
626	wmt_params.flag = 1;
627	wmt_params.dlen = 0;
628	wmt_params.data = NULL;
629	wmt_params.status = &status;
630
631	err = mtk_hci_wmt_sync(hdev, &wmt_params);
632	if (err < 0) {
633		bt_dev_err(hdev, "Failed to query firmware status (%d)", err);
634		return err;
635	}
636
637	if (status == BTMTK_WMT_PATCH_DONE) {
638		bt_dev_info(hdev, "Firmware already downloaded");
639		goto ignore_setup_fw;
640	}
641
642	/* Setup a firmware which the device definitely requires */
643	err = btmtk_setup_firmware(hdev, bdev->data->fwname, mtk_hci_wmt_sync);
644	if (err < 0)
645		return err;
646
647ignore_setup_fw:
648	/* Query whether the device is already enabled */
649	err = readx_poll_timeout(btmtkuart_func_query, hdev, status,
650				 status < 0 || status != BTMTK_WMT_ON_PROGRESS,
651				 2000, 5000000);
652	/* -ETIMEDOUT happens */
653	if (err < 0)
654		return err;
655
656	/* The other errors happen in btusb_mtk_func_query */
657	if (status < 0)
658		return status;
659
660	if (status == BTMTK_WMT_ON_DONE) {
661		bt_dev_info(hdev, "function already on");
662		goto ignore_func_on;
663	}
664
665	/* Enable Bluetooth protocol */
666	wmt_params.op = BTMTK_WMT_FUNC_CTRL;
667	wmt_params.flag = 0;
668	wmt_params.dlen = sizeof(param);
669	wmt_params.data = &param;
670	wmt_params.status = NULL;
671
672	err = mtk_hci_wmt_sync(hdev, &wmt_params);
673	if (err < 0) {
674		bt_dev_err(hdev, "Failed to send wmt func ctrl (%d)", err);
675		return err;
676	}
677
678ignore_func_on:
679	/* Apply the low power environment setup */
680	tci_sleep.mode = 0x5;
681	tci_sleep.duration = cpu_to_le16(0x640);
682	tci_sleep.host_duration = cpu_to_le16(0x640);
683	tci_sleep.host_wakeup_pin = 0;
684	tci_sleep.time_compensation = 0;
685
686	skb = __hci_cmd_sync(hdev, 0xfc7a, sizeof(tci_sleep), &tci_sleep,
687			     HCI_INIT_TIMEOUT);
688	if (IS_ERR(skb)) {
689		err = PTR_ERR(skb);
690		bt_dev_err(hdev, "Failed to apply low power setting (%d)", err);
691		return err;
692	}
693	kfree_skb(skb);
694
695	rettime = ktime_get();
696	delta = ktime_sub(rettime, calltime);
697	duration = (unsigned long long)ktime_to_ns(delta) >> 10;
698
699	bt_dev_info(hdev, "Device setup in %llu usecs", duration);
700
701	return 0;
702}
703
704static int btmtkuart_shutdown(struct hci_dev *hdev)
705{
706	struct btmtk_hci_wmt_params wmt_params;
707	u8 param = 0x0;
708	int err;
709
710	/* Disable the device */
711	wmt_params.op = BTMTK_WMT_FUNC_CTRL;
712	wmt_params.flag = 0;
713	wmt_params.dlen = sizeof(param);
714	wmt_params.data = &param;
715	wmt_params.status = NULL;
716
717	err = mtk_hci_wmt_sync(hdev, &wmt_params);
718	if (err < 0) {
719		bt_dev_err(hdev, "Failed to send wmt func ctrl (%d)", err);
720		return err;
721	}
722
723	return 0;
724}
725
726static int btmtkuart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
727{
728	struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
729	struct mtk_stp_hdr *shdr;
730	int err, dlen, type = 0;
731
732	/* Prepend skb with frame type */
733	memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
734
735	/* Make sure that there is enough rooms for STP header and trailer */
736	if (unlikely(skb_headroom(skb) < sizeof(*shdr)) ||
737	    (skb_tailroom(skb) < MTK_STP_TLR_SIZE)) {
738		err = pskb_expand_head(skb, sizeof(*shdr), MTK_STP_TLR_SIZE,
739				       GFP_ATOMIC);
740		if (err < 0)
741			return err;
742	}
743
744	/* Add the STP header */
745	dlen = skb->len;
746	shdr = skb_push(skb, sizeof(*shdr));
747	shdr->prefix = 0x80;
748	shdr->dlen = cpu_to_be16((dlen & 0x0fff) | (type << 12));
749	shdr->cs = 0;		/* MT7622 doesn't care about checksum value */
750
751	/* Add the STP trailer */
752	skb_put_zero(skb, MTK_STP_TLR_SIZE);
753
754	skb_queue_tail(&bdev->txq, skb);
755
756	btmtkuart_tx_wakeup(bdev);
757	return 0;
758}
759
760static int btmtkuart_parse_dt(struct serdev_device *serdev)
761{
762	struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
763	struct device_node *node = serdev->dev.of_node;
764	u32 speed = 921600;
765	int err;
766
767	if (btmtkuart_is_standalone(bdev)) {
768		of_property_read_u32(node, "current-speed", &speed);
769
770		bdev->desired_speed = speed;
771
772		bdev->vcc = devm_regulator_get(&serdev->dev, "vcc");
773		if (IS_ERR(bdev->vcc)) {
774			err = PTR_ERR(bdev->vcc);
775			return err;
776		}
777
778		bdev->osc = devm_clk_get_optional(&serdev->dev, "osc");
779		if (IS_ERR(bdev->osc)) {
780			err = PTR_ERR(bdev->osc);
781			return err;
782		}
783
784		bdev->boot = devm_gpiod_get_optional(&serdev->dev, "boot",
785						     GPIOD_OUT_LOW);
786		if (IS_ERR(bdev->boot)) {
787			err = PTR_ERR(bdev->boot);
788			return err;
789		}
790
791		bdev->pinctrl = devm_pinctrl_get(&serdev->dev);
792		if (IS_ERR(bdev->pinctrl)) {
793			err = PTR_ERR(bdev->pinctrl);
794			return err;
795		}
796
797		bdev->pins_boot = pinctrl_lookup_state(bdev->pinctrl,
798						       "default");
799		if (IS_ERR(bdev->pins_boot) && !bdev->boot) {
800			err = PTR_ERR(bdev->pins_boot);
801			dev_err(&serdev->dev,
802				"Should assign RXD to LOW at boot stage\n");
803			return err;
804		}
805
806		bdev->pins_runtime = pinctrl_lookup_state(bdev->pinctrl,
807							  "runtime");
808		if (IS_ERR(bdev->pins_runtime)) {
809			err = PTR_ERR(bdev->pins_runtime);
810			return err;
811		}
812
813		bdev->reset = devm_gpiod_get_optional(&serdev->dev, "reset",
814						      GPIOD_OUT_LOW);
815		if (IS_ERR(bdev->reset)) {
816			err = PTR_ERR(bdev->reset);
817			return err;
818		}
819	} else if (btmtkuart_is_builtin_soc(bdev)) {
820		bdev->clk = devm_clk_get(&serdev->dev, "ref");
821		if (IS_ERR(bdev->clk))
822			return PTR_ERR(bdev->clk);
823	}
824
825	return 0;
826}
827
828static int btmtkuart_probe(struct serdev_device *serdev)
829{
830	struct btmtkuart_dev *bdev;
831	struct hci_dev *hdev;
832	int err;
833
834	bdev = devm_kzalloc(&serdev->dev, sizeof(*bdev), GFP_KERNEL);
835	if (!bdev)
836		return -ENOMEM;
837
838	bdev->data = of_device_get_match_data(&serdev->dev);
839	if (!bdev->data)
840		return -ENODEV;
841
842	bdev->serdev = serdev;
843	serdev_device_set_drvdata(serdev, bdev);
844
845	serdev_device_set_client_ops(serdev, &btmtkuart_client_ops);
846
847	err = btmtkuart_parse_dt(serdev);
848	if (err < 0)
849		return err;
850
851	INIT_WORK(&bdev->tx_work, btmtkuart_tx_work);
852	skb_queue_head_init(&bdev->txq);
853
854	/* Initialize and register HCI device */
855	hdev = hci_alloc_dev();
856	if (!hdev) {
857		dev_err(&serdev->dev, "Can't allocate HCI device\n");
858		return -ENOMEM;
859	}
860
861	bdev->hdev = hdev;
862	bdev->hu.hdev = hdev;
863
864	hdev->bus = HCI_UART;
865	hci_set_drvdata(hdev, bdev);
866
867	hdev->open     = btmtkuart_open;
868	hdev->close    = btmtkuart_close;
869	hdev->flush    = btmtkuart_flush;
870	hdev->setup    = btmtkuart_setup;
871	hdev->shutdown = btmtkuart_shutdown;
872	hdev->send     = btmtkuart_send_frame;
873	hdev->set_bdaddr = btmtk_set_bdaddr;
874	SET_HCIDEV_DEV(hdev, &serdev->dev);
875
876	hdev->manufacturer = 70;
877	hci_set_quirk(hdev, HCI_QUIRK_NON_PERSISTENT_SETUP);
878
879	if (btmtkuart_is_standalone(bdev)) {
880		err = clk_prepare_enable(bdev->osc);
881		if (err < 0)
882			goto err_hci_free_dev;
883
884		if (bdev->boot) {
885			gpiod_set_value_cansleep(bdev->boot, 1);
886		} else {
887			/* Switch to the specific pin state for the booting
888			 * requires.
889			 */
890			pinctrl_select_state(bdev->pinctrl, bdev->pins_boot);
891		}
892
893		/* Power on */
894		err = regulator_enable(bdev->vcc);
895		if (err < 0)
896			goto err_clk_disable_unprepare;
897
898		/* Reset if the reset-gpios is available otherwise the board
899		 * -level design should be guaranteed.
900		 */
901		if (bdev->reset) {
902			gpiod_set_value_cansleep(bdev->reset, 1);
903			usleep_range(1000, 2000);
904			gpiod_set_value_cansleep(bdev->reset, 0);
905		}
906
907		/* Wait some time until device got ready and switch to the pin
908		 * mode the device requires for UART transfers.
909		 */
910		msleep(50);
911
912		if (bdev->boot)
913			devm_gpiod_put(&serdev->dev, bdev->boot);
914
915		pinctrl_select_state(bdev->pinctrl, bdev->pins_runtime);
916
917		/* A standalone device doesn't depends on power domain on SoC,
918		 * so mark it as no callbacks.
919		 */
920		pm_runtime_no_callbacks(&serdev->dev);
921
922		set_bit(BTMTKUART_REQUIRED_WAKEUP, &bdev->tx_state);
923	}
924
925	err = hci_register_dev(hdev);
926	if (err < 0) {
927		dev_err(&serdev->dev, "Can't register HCI device\n");
928		goto err_regulator_disable;
929	}
930
931	return 0;
932
933err_regulator_disable:
934	if (btmtkuart_is_standalone(bdev))
935		regulator_disable(bdev->vcc);
936err_clk_disable_unprepare:
937	if (btmtkuart_is_standalone(bdev))
938		clk_disable_unprepare(bdev->osc);
939err_hci_free_dev:
940	hci_free_dev(hdev);
941
942	return err;
943}
944
945static void btmtkuart_remove(struct serdev_device *serdev)
946{
947	struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
948	struct hci_dev *hdev = bdev->hdev;
949
950	if (btmtkuart_is_standalone(bdev)) {
951		regulator_disable(bdev->vcc);
952		clk_disable_unprepare(bdev->osc);
953	}
954
955	hci_unregister_dev(hdev);
956	hci_free_dev(hdev);
957}
958
959static const struct btmtkuart_data mt7622_data __maybe_unused = {
960	.fwname = FIRMWARE_MT7622,
961};
962
963static const struct btmtkuart_data mt7663_data __maybe_unused = {
964	.flags = BTMTKUART_FLAG_STANDALONE_HW,
965	.fwname = FIRMWARE_MT7663,
966};
967
968static const struct btmtkuart_data mt7668_data __maybe_unused = {
969	.flags = BTMTKUART_FLAG_STANDALONE_HW,
970	.fwname = FIRMWARE_MT7668,
971};
972
973#ifdef CONFIG_OF
974static const struct of_device_id mtk_of_match_table[] = {
975	{ .compatible = "mediatek,mt7622-bluetooth", .data = &mt7622_data},
976	{ .compatible = "mediatek,mt7663u-bluetooth", .data = &mt7663_data},
977	{ .compatible = "mediatek,mt7668u-bluetooth", .data = &mt7668_data},
978	{ }
979};
980MODULE_DEVICE_TABLE(of, mtk_of_match_table);
981#endif
982
983static struct serdev_device_driver btmtkuart_driver = {
984	.probe = btmtkuart_probe,
985	.remove = btmtkuart_remove,
986	.driver = {
987		.name = "btmtkuart",
988		.of_match_table = of_match_ptr(mtk_of_match_table),
989	},
990};
991
992module_serdev_device_driver(btmtkuart_driver);
993
994MODULE_AUTHOR("Sean Wang <sean.wang@mediatek.com>");
995MODULE_DESCRIPTION("MediaTek Bluetooth Serial driver ver " VERSION);
996MODULE_VERSION(VERSION);
997MODULE_LICENSE("GPL");