1 /*
2  *
3  *  Bluetooth HCI UART driver for marvell devices
4  *
5  *  Copyright (C) 2016  Marvell International Ltd.
6  *  Copyright (C) 2016  Intel Corporation
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License as published by
10  *  the Free Software Foundation; either version 2 of the License, or
11  *  (at your option) any later version.
12  *
13  *  This program is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License
19  *  along with this program; if not, write to the Free Software
20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21  *
22  */
23 
24 #include <linux/kernel.h>
25 #include <linux/errno.h>
26 #include <linux/skbuff.h>
27 #include <linux/firmware.h>
28 #include <linux/module.h>
29 #include <linux/tty.h>
30 
31 #include <net/bluetooth/bluetooth.h>
32 #include <net/bluetooth/hci_core.h>
33 
34 #include "hci_uart.h"
35 
36 #define HCI_FW_REQ_PKT 0xA5
37 #define HCI_CHIP_VER_PKT 0xAA
38 
39 #define MRVL_ACK 0x5A
40 #define MRVL_NAK 0xBF
41 #define MRVL_RAW_DATA 0x1F
42 
43 enum {
44 	STATE_CHIP_VER_PENDING,
45 	STATE_FW_REQ_PENDING,
46 };
47 
48 struct mrvl_data {
49 	struct sk_buff *rx_skb;
50 	struct sk_buff_head txq;
51 	struct sk_buff_head rawq;
52 	unsigned long flags;
53 	unsigned int tx_len;
54 	u8 id, rev;
55 };
56 
57 struct hci_mrvl_pkt {
58 	__le16 lhs;
59 	__le16 rhs;
60 } __packed;
61 #define HCI_MRVL_PKT_SIZE 4
62 
mrvl_open(struct hci_uart * hu)63 static int mrvl_open(struct hci_uart *hu)
64 {
65 	struct mrvl_data *mrvl;
66 
67 	BT_DBG("hu %p", hu);
68 
69 	if (!hci_uart_has_flow_control(hu))
70 		return -EOPNOTSUPP;
71 
72 	mrvl = kzalloc(sizeof(*mrvl), GFP_KERNEL);
73 	if (!mrvl)
74 		return -ENOMEM;
75 
76 	skb_queue_head_init(&mrvl->txq);
77 	skb_queue_head_init(&mrvl->rawq);
78 
79 	set_bit(STATE_CHIP_VER_PENDING, &mrvl->flags);
80 
81 	hu->priv = mrvl;
82 	return 0;
83 }
84 
mrvl_close(struct hci_uart * hu)85 static int mrvl_close(struct hci_uart *hu)
86 {
87 	struct mrvl_data *mrvl = hu->priv;
88 
89 	BT_DBG("hu %p", hu);
90 
91 	skb_queue_purge(&mrvl->txq);
92 	skb_queue_purge(&mrvl->rawq);
93 	kfree_skb(mrvl->rx_skb);
94 	kfree(mrvl);
95 
96 	hu->priv = NULL;
97 	return 0;
98 }
99 
mrvl_flush(struct hci_uart * hu)100 static int mrvl_flush(struct hci_uart *hu)
101 {
102 	struct mrvl_data *mrvl = hu->priv;
103 
104 	BT_DBG("hu %p", hu);
105 
106 	skb_queue_purge(&mrvl->txq);
107 	skb_queue_purge(&mrvl->rawq);
108 
109 	return 0;
110 }
111 
mrvl_dequeue(struct hci_uart * hu)112 static struct sk_buff *mrvl_dequeue(struct hci_uart *hu)
113 {
114 	struct mrvl_data *mrvl = hu->priv;
115 	struct sk_buff *skb;
116 
117 	skb = skb_dequeue(&mrvl->txq);
118 	if (!skb) {
119 		/* Any raw data ? */
120 		skb = skb_dequeue(&mrvl->rawq);
121 	} else {
122 		/* Prepend skb with frame type */
123 		memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
124 	}
125 
126 	return skb;
127 }
128 
mrvl_enqueue(struct hci_uart * hu,struct sk_buff * skb)129 static int mrvl_enqueue(struct hci_uart *hu, struct sk_buff *skb)
130 {
131 	struct mrvl_data *mrvl = hu->priv;
132 
133 	skb_queue_tail(&mrvl->txq, skb);
134 	return 0;
135 }
136 
mrvl_send_ack(struct hci_uart * hu,unsigned char type)137 static void mrvl_send_ack(struct hci_uart *hu, unsigned char type)
138 {
139 	struct mrvl_data *mrvl = hu->priv;
140 	struct sk_buff *skb;
141 
142 	/* No H4 payload, only 1 byte header */
143 	skb = bt_skb_alloc(0, GFP_ATOMIC);
144 	if (!skb) {
145 		bt_dev_err(hu->hdev, "Unable to alloc ack/nak packet");
146 		return;
147 	}
148 	hci_skb_pkt_type(skb) = type;
149 
150 	skb_queue_tail(&mrvl->txq, skb);
151 	hci_uart_tx_wakeup(hu);
152 }
153 
mrvl_recv_fw_req(struct hci_dev * hdev,struct sk_buff * skb)154 static int mrvl_recv_fw_req(struct hci_dev *hdev, struct sk_buff *skb)
155 {
156 	struct hci_mrvl_pkt *pkt = (void *)skb->data;
157 	struct hci_uart *hu = hci_get_drvdata(hdev);
158 	struct mrvl_data *mrvl = hu->priv;
159 	int ret = 0;
160 
161 	if ((pkt->lhs ^ pkt->rhs) != 0xffff) {
162 		bt_dev_err(hdev, "Corrupted mrvl header");
163 		mrvl_send_ack(hu, MRVL_NAK);
164 		ret = -EINVAL;
165 		goto done;
166 	}
167 	mrvl_send_ack(hu, MRVL_ACK);
168 
169 	if (!test_bit(STATE_FW_REQ_PENDING, &mrvl->flags)) {
170 		bt_dev_err(hdev, "Received unexpected firmware request");
171 		ret = -EINVAL;
172 		goto done;
173 	}
174 
175 	mrvl->tx_len = le16_to_cpu(pkt->lhs);
176 
177 	clear_bit(STATE_FW_REQ_PENDING, &mrvl->flags);
178 	smp_mb__after_atomic();
179 	wake_up_bit(&mrvl->flags, STATE_FW_REQ_PENDING);
180 
181 done:
182 	kfree_skb(skb);
183 	return ret;
184 }
185 
mrvl_recv_chip_ver(struct hci_dev * hdev,struct sk_buff * skb)186 static int mrvl_recv_chip_ver(struct hci_dev *hdev, struct sk_buff *skb)
187 {
188 	struct hci_mrvl_pkt *pkt = (void *)skb->data;
189 	struct hci_uart *hu = hci_get_drvdata(hdev);
190 	struct mrvl_data *mrvl = hu->priv;
191 	u16 version = le16_to_cpu(pkt->lhs);
192 	int ret = 0;
193 
194 	if ((pkt->lhs ^ pkt->rhs) != 0xffff) {
195 		bt_dev_err(hdev, "Corrupted mrvl header");
196 		mrvl_send_ack(hu, MRVL_NAK);
197 		ret = -EINVAL;
198 		goto done;
199 	}
200 	mrvl_send_ack(hu, MRVL_ACK);
201 
202 	if (!test_bit(STATE_CHIP_VER_PENDING, &mrvl->flags)) {
203 		bt_dev_err(hdev, "Received unexpected chip version");
204 		goto done;
205 	}
206 
207 	mrvl->id = version;
208 	mrvl->rev = version >> 8;
209 
210 	bt_dev_info(hdev, "Controller id = %x, rev = %x", mrvl->id, mrvl->rev);
211 
212 	clear_bit(STATE_CHIP_VER_PENDING, &mrvl->flags);
213 	smp_mb__after_atomic();
214 	wake_up_bit(&mrvl->flags, STATE_CHIP_VER_PENDING);
215 
216 done:
217 	kfree_skb(skb);
218 	return ret;
219 }
220 
221 #define HCI_RECV_CHIP_VER \
222 	.type = HCI_CHIP_VER_PKT, \
223 	.hlen = HCI_MRVL_PKT_SIZE, \
224 	.loff = 0, \
225 	.lsize = 0, \
226 	.maxlen = HCI_MRVL_PKT_SIZE
227 
228 #define HCI_RECV_FW_REQ \
229 	.type = HCI_FW_REQ_PKT, \
230 	.hlen = HCI_MRVL_PKT_SIZE, \
231 	.loff = 0, \
232 	.lsize = 0, \
233 	.maxlen = HCI_MRVL_PKT_SIZE
234 
235 static const struct h4_recv_pkt mrvl_recv_pkts[] = {
236 	{ H4_RECV_ACL,       .recv = hci_recv_frame     },
237 	{ H4_RECV_SCO,       .recv = hci_recv_frame     },
238 	{ H4_RECV_EVENT,     .recv = hci_recv_frame     },
239 	{ HCI_RECV_FW_REQ,   .recv = mrvl_recv_fw_req   },
240 	{ HCI_RECV_CHIP_VER, .recv = mrvl_recv_chip_ver },
241 };
242 
mrvl_recv(struct hci_uart * hu,const void * data,int count)243 static int mrvl_recv(struct hci_uart *hu, const void *data, int count)
244 {
245 	struct mrvl_data *mrvl = hu->priv;
246 
247 	if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
248 		return -EUNATCH;
249 
250 	mrvl->rx_skb = h4_recv_buf(hu->hdev, mrvl->rx_skb, data, count,
251 				    mrvl_recv_pkts,
252 				    ARRAY_SIZE(mrvl_recv_pkts));
253 	if (IS_ERR(mrvl->rx_skb)) {
254 		int err = PTR_ERR(mrvl->rx_skb);
255 		bt_dev_err(hu->hdev, "Frame reassembly failed (%d)", err);
256 		mrvl->rx_skb = NULL;
257 		return err;
258 	}
259 
260 	return count;
261 }
262 
mrvl_load_firmware(struct hci_dev * hdev,const char * name)263 static int mrvl_load_firmware(struct hci_dev *hdev, const char *name)
264 {
265 	struct hci_uart *hu = hci_get_drvdata(hdev);
266 	struct mrvl_data *mrvl = hu->priv;
267 	const struct firmware *fw = NULL;
268 	const u8 *fw_ptr, *fw_max;
269 	int err;
270 
271 	err = request_firmware(&fw, name, &hdev->dev);
272 	if (err < 0) {
273 		bt_dev_err(hdev, "Failed to load firmware file %s", name);
274 		return err;
275 	}
276 
277 	fw_ptr = fw->data;
278 	fw_max = fw->data + fw->size;
279 
280 	bt_dev_info(hdev, "Loading %s", name);
281 
282 	set_bit(STATE_FW_REQ_PENDING, &mrvl->flags);
283 
284 	while (fw_ptr <= fw_max) {
285 		struct sk_buff *skb;
286 
287 		/* Controller drives the firmware load by sending firmware
288 		 * request packets containing the expected fragment size.
289 		 */
290 		err = wait_on_bit_timeout(&mrvl->flags, STATE_FW_REQ_PENDING,
291 					  TASK_INTERRUPTIBLE,
292 					  msecs_to_jiffies(2000));
293 		if (err == 1) {
294 			bt_dev_err(hdev, "Firmware load interrupted");
295 			err = -EINTR;
296 			break;
297 		} else if (err) {
298 			bt_dev_err(hdev, "Firmware request timeout");
299 			err = -ETIMEDOUT;
300 			break;
301 		}
302 
303 		bt_dev_dbg(hdev, "Firmware request, expecting %d bytes",
304 			   mrvl->tx_len);
305 
306 		if (fw_ptr == fw_max) {
307 			/* Controller requests a null size once firmware is
308 			 * fully loaded. If controller expects more data, there
309 			 * is an issue.
310 			 */
311 			if (!mrvl->tx_len) {
312 				bt_dev_info(hdev, "Firmware loading complete");
313 			} else {
314 				bt_dev_err(hdev, "Firmware loading failure");
315 				err = -EINVAL;
316 			}
317 			break;
318 		}
319 
320 		if (fw_ptr + mrvl->tx_len > fw_max) {
321 			mrvl->tx_len = fw_max - fw_ptr;
322 			bt_dev_dbg(hdev, "Adjusting tx_len to %d",
323 				   mrvl->tx_len);
324 		}
325 
326 		skb = bt_skb_alloc(mrvl->tx_len, GFP_KERNEL);
327 		if (!skb) {
328 			bt_dev_err(hdev, "Failed to alloc mem for FW packet");
329 			err = -ENOMEM;
330 			break;
331 		}
332 		bt_cb(skb)->pkt_type = MRVL_RAW_DATA;
333 
334 		skb_put_data(skb, fw_ptr, mrvl->tx_len);
335 		fw_ptr += mrvl->tx_len;
336 
337 		set_bit(STATE_FW_REQ_PENDING, &mrvl->flags);
338 
339 		skb_queue_tail(&mrvl->rawq, skb);
340 		hci_uart_tx_wakeup(hu);
341 	}
342 
343 	release_firmware(fw);
344 	return err;
345 }
346 
mrvl_setup(struct hci_uart * hu)347 static int mrvl_setup(struct hci_uart *hu)
348 {
349 	int err;
350 
351 	hci_uart_set_flow_control(hu, true);
352 
353 	err = mrvl_load_firmware(hu->hdev, "mrvl/helper_uart_3000000.bin");
354 	if (err) {
355 		bt_dev_err(hu->hdev, "Unable to download firmware helper");
356 		return -EINVAL;
357 	}
358 
359 	hci_uart_set_baudrate(hu, 3000000);
360 	hci_uart_set_flow_control(hu, false);
361 
362 	err = mrvl_load_firmware(hu->hdev, "mrvl/uart8897_bt.bin");
363 	if (err)
364 		return err;
365 
366 	return 0;
367 }
368 
369 static const struct hci_uart_proto mrvl_proto = {
370 	.id		= HCI_UART_MRVL,
371 	.name		= "Marvell",
372 	.init_speed	= 115200,
373 	.open		= mrvl_open,
374 	.close		= mrvl_close,
375 	.flush		= mrvl_flush,
376 	.setup		= mrvl_setup,
377 	.recv		= mrvl_recv,
378 	.enqueue	= mrvl_enqueue,
379 	.dequeue	= mrvl_dequeue,
380 };
381 
mrvl_init(void)382 int __init mrvl_init(void)
383 {
384 	return hci_uart_register_proto(&mrvl_proto);
385 }
386 
mrvl_deinit(void)387 int __exit mrvl_deinit(void)
388 {
389 	return hci_uart_unregister_proto(&mrvl_proto);
390 }
391