xref: /openbmc/linux/drivers/bluetooth/hci_ath.c (revision 9b93eb47)
1 /*
2  *  Atheros Communication Bluetooth HCIATH3K UART protocol
3  *
4  *  HCIATH3K (HCI Atheros AR300x Protocol) is a Atheros Communication's
5  *  power management protocol extension to H4 to support AR300x Bluetooth Chip.
6  *
7  *  Copyright (c) 2009-2010 Atheros Communications Inc.
8  *
9  *  Acknowledgements:
10  *  This file is based on hci_h4.c, which was written
11  *  by Maxim Krasnyansky and Marcel Holtmann.
12  *
13  *  This program is free software; you can redistribute it and/or modify
14  *  it under the terms of the GNU General Public License as published by
15  *  the Free Software Foundation; either version 2 of the License, or
16  *  (at your option) any later version.
17  *
18  *  This program is distributed in the hope that it will be useful,
19  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
20  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  *  GNU General Public License for more details.
22  *
23  *  You should have received a copy of the GNU General Public License
24  *  along with this program; if not, write to the Free Software
25  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
26  *
27  */
28 
29 #include <linux/module.h>
30 #include <linux/kernel.h>
31 
32 #include <linux/init.h>
33 #include <linux/slab.h>
34 #include <linux/tty.h>
35 #include <linux/errno.h>
36 #include <linux/ioctl.h>
37 #include <linux/skbuff.h>
38 
39 #include <net/bluetooth/bluetooth.h>
40 #include <net/bluetooth/hci_core.h>
41 
42 #include "hci_uart.h"
43 
44 struct ath_struct {
45 	struct hci_uart *hu;
46 	unsigned int cur_sleep;
47 
48 	struct sk_buff *rx_skb;
49 	struct sk_buff_head txq;
50 	struct work_struct ctxtsw;
51 };
52 
53 #define OP_WRITE_TAG	0x01
54 
55 #define INDEX_BDADDR	0x01
56 
57 struct ath_vendor_cmd {
58 	__u8 opcode;
59 	__le16 index;
60 	__u8 len;
61 	__u8 data[251];
62 } __packed;
63 
64 static int ath_wakeup_ar3k(struct tty_struct *tty)
65 {
66 	int status = tty->driver->ops->tiocmget(tty);
67 
68 	if (status & TIOCM_CTS)
69 		return status;
70 
71 	/* Clear RTS first */
72 	tty->driver->ops->tiocmget(tty);
73 	tty->driver->ops->tiocmset(tty, 0x00, TIOCM_RTS);
74 	msleep(20);
75 
76 	/* Set RTS, wake up board */
77 	tty->driver->ops->tiocmget(tty);
78 	tty->driver->ops->tiocmset(tty, TIOCM_RTS, 0x00);
79 	msleep(20);
80 
81 	status = tty->driver->ops->tiocmget(tty);
82 	return status;
83 }
84 
85 static void ath_hci_uart_work(struct work_struct *work)
86 {
87 	int status;
88 	struct ath_struct *ath;
89 	struct hci_uart *hu;
90 	struct tty_struct *tty;
91 
92 	ath = container_of(work, struct ath_struct, ctxtsw);
93 
94 	hu = ath->hu;
95 	tty = hu->tty;
96 
97 	/* verify and wake up controller */
98 	if (ath->cur_sleep) {
99 		status = ath_wakeup_ar3k(tty);
100 		if (!(status & TIOCM_CTS))
101 			return;
102 	}
103 
104 	/* Ready to send Data */
105 	clear_bit(HCI_UART_SENDING, &hu->tx_state);
106 	hci_uart_tx_wakeup(hu);
107 }
108 
109 static int ath_open(struct hci_uart *hu)
110 {
111 	struct ath_struct *ath;
112 
113 	BT_DBG("hu %p", hu);
114 
115 	ath = kzalloc(sizeof(*ath), GFP_KERNEL);
116 	if (!ath)
117 		return -ENOMEM;
118 
119 	skb_queue_head_init(&ath->txq);
120 
121 	hu->priv = ath;
122 	ath->hu = hu;
123 
124 	INIT_WORK(&ath->ctxtsw, ath_hci_uart_work);
125 
126 	return 0;
127 }
128 
129 static int ath_close(struct hci_uart *hu)
130 {
131 	struct ath_struct *ath = hu->priv;
132 
133 	BT_DBG("hu %p", hu);
134 
135 	skb_queue_purge(&ath->txq);
136 
137 	kfree_skb(ath->rx_skb);
138 
139 	cancel_work_sync(&ath->ctxtsw);
140 
141 	hu->priv = NULL;
142 	kfree(ath);
143 
144 	return 0;
145 }
146 
147 static int ath_flush(struct hci_uart *hu)
148 {
149 	struct ath_struct *ath = hu->priv;
150 
151 	BT_DBG("hu %p", hu);
152 
153 	skb_queue_purge(&ath->txq);
154 
155 	return 0;
156 }
157 
158 static int ath_vendor_cmd(struct hci_dev *hdev, uint8_t opcode, uint16_t index,
159 			  const void *data, size_t dlen)
160 {
161 	struct sk_buff *skb;
162 	struct ath_vendor_cmd cmd;
163 
164 	if (dlen > sizeof(cmd.data))
165 		return -EINVAL;
166 
167 	cmd.opcode = opcode;
168 	cmd.index = cpu_to_le16(index);
169 	cmd.len = dlen;
170 	memcpy(cmd.data, data, dlen);
171 
172 	skb = __hci_cmd_sync(hdev, 0xfc0b, dlen + 4, &cmd, HCI_INIT_TIMEOUT);
173 	if (IS_ERR(skb))
174 		return PTR_ERR(skb);
175 	kfree_skb(skb);
176 
177 	return 0;
178 }
179 
180 static int ath_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
181 {
182 	return ath_vendor_cmd(hdev, OP_WRITE_TAG, INDEX_BDADDR, bdaddr,
183 			      sizeof(*bdaddr));
184 }
185 
186 static int ath_setup(struct hci_uart *hu)
187 {
188 	BT_DBG("hu %p", hu);
189 
190 	hu->hdev->set_bdaddr = ath_set_bdaddr;
191 
192 	return 0;
193 }
194 
195 static const struct h4_recv_pkt ath_recv_pkts[] = {
196 	{ H4_RECV_ACL,   .recv = hci_recv_frame },
197 	{ H4_RECV_SCO,   .recv = hci_recv_frame },
198 	{ H4_RECV_EVENT, .recv = hci_recv_frame },
199 };
200 
201 static int ath_recv(struct hci_uart *hu, const void *data, int count)
202 {
203 	struct ath_struct *ath = hu->priv;
204 
205 	ath->rx_skb = h4_recv_buf(hu->hdev, ath->rx_skb, data, count,
206 				  ath_recv_pkts, ARRAY_SIZE(ath_recv_pkts));
207 	if (IS_ERR(ath->rx_skb)) {
208 		int err = PTR_ERR(ath->rx_skb);
209 		bt_dev_err(hu->hdev, "Frame reassembly failed (%d)", err);
210 		ath->rx_skb = NULL;
211 		return err;
212 	}
213 
214 	return count;
215 }
216 
217 #define HCI_OP_ATH_SLEEP 0xFC04
218 
219 static int ath_enqueue(struct hci_uart *hu, struct sk_buff *skb)
220 {
221 	struct ath_struct *ath = hu->priv;
222 
223 	if (hci_skb_pkt_type(skb) == HCI_SCODATA_PKT) {
224 		kfree_skb(skb);
225 		return 0;
226 	}
227 
228 	/* Update power management enable flag with parameters of
229 	 * HCI sleep enable vendor specific HCI command.
230 	 */
231 	if (hci_skb_pkt_type(skb) == HCI_COMMAND_PKT) {
232 		struct hci_command_hdr *hdr = (void *)skb->data;
233 
234 		if (__le16_to_cpu(hdr->opcode) == HCI_OP_ATH_SLEEP)
235 			ath->cur_sleep = skb->data[HCI_COMMAND_HDR_SIZE];
236 	}
237 
238 	BT_DBG("hu %p skb %p", hu, skb);
239 
240 	/* Prepend skb with frame type */
241 	memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
242 
243 	skb_queue_tail(&ath->txq, skb);
244 	set_bit(HCI_UART_SENDING, &hu->tx_state);
245 
246 	schedule_work(&ath->ctxtsw);
247 
248 	return 0;
249 }
250 
251 static struct sk_buff *ath_dequeue(struct hci_uart *hu)
252 {
253 	struct ath_struct *ath = hu->priv;
254 
255 	return skb_dequeue(&ath->txq);
256 }
257 
258 static const struct hci_uart_proto athp = {
259 	.id		= HCI_UART_ATH3K,
260 	.name		= "ATH3K",
261 	.manufacturer	= 69,
262 	.open		= ath_open,
263 	.close		= ath_close,
264 	.flush		= ath_flush,
265 	.setup		= ath_setup,
266 	.recv		= ath_recv,
267 	.enqueue	= ath_enqueue,
268 	.dequeue	= ath_dequeue,
269 };
270 
271 int __init ath_init(void)
272 {
273 	return hci_uart_register_proto(&athp);
274 }
275 
276 int __exit ath_deinit(void)
277 {
278 	return hci_uart_unregister_proto(&athp);
279 }
280