xref: /openbmc/linux/drivers/bluetooth/hci_ath.c (revision 275876e2)
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_head txq;
49 	struct work_struct ctxtsw;
50 };
51 
52 static int ath_wakeup_ar3k(struct tty_struct *tty)
53 {
54 	struct ktermios ktermios;
55 	int status = tty->driver->ops->tiocmget(tty);
56 
57 	if (status & TIOCM_CTS)
58 		return status;
59 
60 	/* Disable Automatic RTSCTS */
61 	ktermios = tty->termios;
62 	ktermios.c_cflag &= ~CRTSCTS;
63 	tty_set_termios(tty, &ktermios);
64 
65 	/* Clear RTS first */
66 	status = tty->driver->ops->tiocmget(tty);
67 	tty->driver->ops->tiocmset(tty, 0x00, TIOCM_RTS);
68 	mdelay(20);
69 
70 	/* Set RTS, wake up board */
71 	status = tty->driver->ops->tiocmget(tty);
72 	tty->driver->ops->tiocmset(tty, TIOCM_RTS, 0x00);
73 	mdelay(20);
74 
75 	status = tty->driver->ops->tiocmget(tty);
76 
77 	/* Disable Automatic RTSCTS */
78 	ktermios.c_cflag |= CRTSCTS;
79 	status = tty_set_termios(tty, &ktermios);
80 
81 	return status;
82 }
83 
84 static void ath_hci_uart_work(struct work_struct *work)
85 {
86 	int status;
87 	struct ath_struct *ath;
88 	struct hci_uart *hu;
89 	struct tty_struct *tty;
90 
91 	ath = container_of(work, struct ath_struct, ctxtsw);
92 
93 	hu = ath->hu;
94 	tty = hu->tty;
95 
96 	/* verify and wake up controller */
97 	if (ath->cur_sleep) {
98 		status = ath_wakeup_ar3k(tty);
99 		if (!(status & TIOCM_CTS))
100 			return;
101 	}
102 
103 	/* Ready to send Data */
104 	clear_bit(HCI_UART_SENDING, &hu->tx_state);
105 	hci_uart_tx_wakeup(hu);
106 }
107 
108 /* Initialize protocol */
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 /* Flush protocol data */
130 static int ath_flush(struct hci_uart *hu)
131 {
132 	struct ath_struct *ath = hu->priv;
133 
134 	BT_DBG("hu %p", hu);
135 
136 	skb_queue_purge(&ath->txq);
137 
138 	return 0;
139 }
140 
141 /* Close protocol */
142 static int ath_close(struct hci_uart *hu)
143 {
144 	struct ath_struct *ath = hu->priv;
145 
146 	BT_DBG("hu %p", hu);
147 
148 	skb_queue_purge(&ath->txq);
149 
150 	cancel_work_sync(&ath->ctxtsw);
151 
152 	hu->priv = NULL;
153 	kfree(ath);
154 
155 	return 0;
156 }
157 
158 #define HCI_OP_ATH_SLEEP 0xFC04
159 
160 /* Enqueue frame for transmittion */
161 static int ath_enqueue(struct hci_uart *hu, struct sk_buff *skb)
162 {
163 	struct ath_struct *ath = hu->priv;
164 
165 	if (bt_cb(skb)->pkt_type == HCI_SCODATA_PKT) {
166 		kfree_skb(skb);
167 		return 0;
168 	}
169 
170 	/*
171 	 * Update power management enable flag with parameters of
172 	 * HCI sleep enable vendor specific HCI command.
173 	 */
174 	if (bt_cb(skb)->pkt_type == HCI_COMMAND_PKT) {
175 		struct hci_command_hdr *hdr = (void *)skb->data;
176 
177 		if (__le16_to_cpu(hdr->opcode) == HCI_OP_ATH_SLEEP)
178 			ath->cur_sleep = skb->data[HCI_COMMAND_HDR_SIZE];
179 	}
180 
181 	BT_DBG("hu %p skb %p", hu, skb);
182 
183 	/* Prepend skb with frame type */
184 	memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
185 
186 	skb_queue_tail(&ath->txq, skb);
187 	set_bit(HCI_UART_SENDING, &hu->tx_state);
188 
189 	schedule_work(&ath->ctxtsw);
190 
191 	return 0;
192 }
193 
194 static struct sk_buff *ath_dequeue(struct hci_uart *hu)
195 {
196 	struct ath_struct *ath = hu->priv;
197 
198 	return skb_dequeue(&ath->txq);
199 }
200 
201 /* Recv data */
202 static int ath_recv(struct hci_uart *hu, void *data, int count)
203 {
204 	int ret;
205 
206 	ret = hci_recv_stream_fragment(hu->hdev, data, count);
207 	if (ret < 0) {
208 		BT_ERR("Frame Reassembly Failed");
209 		return ret;
210 	}
211 
212 	return count;
213 }
214 
215 static struct hci_uart_proto athp = {
216 	.id = HCI_UART_ATH3K,
217 	.open = ath_open,
218 	.close = ath_close,
219 	.recv = ath_recv,
220 	.enqueue = ath_enqueue,
221 	.dequeue = ath_dequeue,
222 	.flush = ath_flush,
223 };
224 
225 int __init ath_init(void)
226 {
227 	int err = hci_uart_register_proto(&athp);
228 
229 	if (!err)
230 		BT_INFO("HCIATH3K protocol initialized");
231 	else
232 		BT_ERR("HCIATH3K protocol registration failed");
233 
234 	return err;
235 }
236 
237 int __exit ath_deinit(void)
238 {
239 	return hci_uart_unregister_proto(&athp);
240 }
241