xref: /openbmc/linux/drivers/bluetooth/hci_bcm.c (revision bbde9fc1824aab58bc78c084163007dd6c03fe5b)
1 /*
2  *
3  *  Bluetooth HCI UART driver for Broadcom devices
4  *
5  *  Copyright (C) 2015  Intel Corporation
6  *
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 
29 #include <net/bluetooth/bluetooth.h>
30 #include <net/bluetooth/hci_core.h>
31 
32 #include "btbcm.h"
33 #include "hci_uart.h"
34 
35 struct bcm_data {
36 	struct sk_buff *rx_skb;
37 	struct sk_buff_head txq;
38 };
39 
40 static int bcm_set_baudrate(struct hci_uart *hu, unsigned int speed)
41 {
42 	struct hci_dev *hdev = hu->hdev;
43 	struct sk_buff *skb;
44 	struct bcm_update_uart_baud_rate param;
45 
46 	if (speed > 3000000) {
47 		struct bcm_write_uart_clock_setting clock;
48 
49 		clock.type = BCM_UART_CLOCK_48MHZ;
50 
51 		BT_DBG("%s: Set Controller clock (%d)", hdev->name, clock.type);
52 
53 		/* This Broadcom specific command changes the UART's controller
54 		 * clock for baud rate > 3000000.
55 		 */
56 		skb = __hci_cmd_sync(hdev, 0xfc45, 1, &clock, HCI_INIT_TIMEOUT);
57 		if (IS_ERR(skb)) {
58 			int err = PTR_ERR(skb);
59 			BT_ERR("%s: BCM: failed to write clock command (%d)",
60 			       hdev->name, err);
61 			return err;
62 		}
63 
64 		kfree_skb(skb);
65 	}
66 
67 	BT_DBG("%s: Set Controller UART speed to %d bit/s", hdev->name, speed);
68 
69 	param.zero = cpu_to_le16(0);
70 	param.baud_rate = cpu_to_le32(speed);
71 
72 	/* This Broadcom specific command changes the UART's controller baud
73 	 * rate.
74 	 */
75 	skb = __hci_cmd_sync(hdev, 0xfc18, sizeof(param), &param,
76 			     HCI_INIT_TIMEOUT);
77 	if (IS_ERR(skb)) {
78 		int err = PTR_ERR(skb);
79 		BT_ERR("%s: BCM: failed to write update baudrate command (%d)",
80 		       hdev->name, err);
81 		return err;
82 	}
83 
84 	kfree_skb(skb);
85 
86 	return 0;
87 }
88 
89 static int bcm_open(struct hci_uart *hu)
90 {
91 	struct bcm_data *bcm;
92 
93 	BT_DBG("hu %p", hu);
94 
95 	bcm = kzalloc(sizeof(*bcm), GFP_KERNEL);
96 	if (!bcm)
97 		return -ENOMEM;
98 
99 	skb_queue_head_init(&bcm->txq);
100 
101 	hu->priv = bcm;
102 	return 0;
103 }
104 
105 static int bcm_close(struct hci_uart *hu)
106 {
107 	struct bcm_data *bcm = hu->priv;
108 
109 	BT_DBG("hu %p", hu);
110 
111 	skb_queue_purge(&bcm->txq);
112 	kfree_skb(bcm->rx_skb);
113 	kfree(bcm);
114 
115 	hu->priv = NULL;
116 	return 0;
117 }
118 
119 static int bcm_flush(struct hci_uart *hu)
120 {
121 	struct bcm_data *bcm = hu->priv;
122 
123 	BT_DBG("hu %p", hu);
124 
125 	skb_queue_purge(&bcm->txq);
126 
127 	return 0;
128 }
129 
130 static int bcm_setup(struct hci_uart *hu)
131 {
132 	char fw_name[64];
133 	const struct firmware *fw;
134 	unsigned int speed;
135 	int err;
136 
137 	BT_DBG("hu %p", hu);
138 
139 	hu->hdev->set_bdaddr = btbcm_set_bdaddr;
140 
141 	err = btbcm_initialize(hu->hdev, fw_name, sizeof(fw_name));
142 	if (err)
143 		return err;
144 
145 	err = request_firmware(&fw, fw_name, &hu->hdev->dev);
146 	if (err < 0) {
147 		BT_INFO("%s: BCM: Patch %s not found", hu->hdev->name, fw_name);
148 		return 0;
149 	}
150 
151 	err = btbcm_patchram(hu->hdev, fw);
152 	if (err) {
153 		BT_INFO("%s: BCM: Patch failed (%d)", hu->hdev->name, err);
154 		goto finalize;
155 	}
156 
157 	/* Init speed if any */
158 	if (hu->init_speed)
159 		speed = hu->init_speed;
160 	else if (hu->proto->init_speed)
161 		speed = hu->proto->init_speed;
162 	else
163 		speed = 0;
164 
165 	if (speed)
166 		hci_uart_set_baudrate(hu, speed);
167 
168 	/* Operational speed if any */
169 	if (hu->oper_speed)
170 		speed = hu->oper_speed;
171 	else if (hu->proto->oper_speed)
172 		speed = hu->proto->oper_speed;
173 	else
174 		speed = 0;
175 
176 	if (speed) {
177 		err = bcm_set_baudrate(hu, speed);
178 		if (!err)
179 			hci_uart_set_baudrate(hu, speed);
180 	}
181 
182 finalize:
183 	release_firmware(fw);
184 
185 	err = btbcm_finalize(hu->hdev);
186 
187 	return err;
188 }
189 
190 static const struct h4_recv_pkt bcm_recv_pkts[] = {
191 	{ H4_RECV_ACL,   .recv = hci_recv_frame },
192 	{ H4_RECV_SCO,   .recv = hci_recv_frame },
193 	{ H4_RECV_EVENT, .recv = hci_recv_frame },
194 };
195 
196 static int bcm_recv(struct hci_uart *hu, const void *data, int count)
197 {
198 	struct bcm_data *bcm = hu->priv;
199 
200 	if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
201 		return -EUNATCH;
202 
203 	bcm->rx_skb = h4_recv_buf(hu->hdev, bcm->rx_skb, data, count,
204 				  bcm_recv_pkts, ARRAY_SIZE(bcm_recv_pkts));
205 	if (IS_ERR(bcm->rx_skb)) {
206 		int err = PTR_ERR(bcm->rx_skb);
207 		BT_ERR("%s: Frame reassembly failed (%d)", hu->hdev->name, err);
208 		bcm->rx_skb = NULL;
209 		return err;
210 	}
211 
212 	return count;
213 }
214 
215 static int bcm_enqueue(struct hci_uart *hu, struct sk_buff *skb)
216 {
217 	struct bcm_data *bcm = hu->priv;
218 
219 	BT_DBG("hu %p skb %p", hu, skb);
220 
221 	/* Prepend skb with frame type */
222 	memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
223 	skb_queue_tail(&bcm->txq, skb);
224 
225 	return 0;
226 }
227 
228 static struct sk_buff *bcm_dequeue(struct hci_uart *hu)
229 {
230 	struct bcm_data *bcm = hu->priv;
231 
232 	return skb_dequeue(&bcm->txq);
233 }
234 
235 static const struct hci_uart_proto bcm_proto = {
236 	.id		= HCI_UART_BCM,
237 	.name		= "BCM",
238 	.init_speed	= 115200,
239 	.oper_speed	= 4000000,
240 	.open		= bcm_open,
241 	.close		= bcm_close,
242 	.flush		= bcm_flush,
243 	.setup		= bcm_setup,
244 	.set_baudrate	= bcm_set_baudrate,
245 	.recv		= bcm_recv,
246 	.enqueue	= bcm_enqueue,
247 	.dequeue	= bcm_dequeue,
248 };
249 
250 int __init bcm_init(void)
251 {
252 	return hci_uart_register_proto(&bcm_proto);
253 }
254 
255 int __exit bcm_deinit(void)
256 {
257 	return hci_uart_unregister_proto(&bcm_proto);
258 }
259