1/*
2 * Texas Instrument's Bluetooth Driver For Shared Transport.
3 *
4 * Bluetooth Driver acts as interface between HCI core and
5 * TI Shared Transport Layer.
6 *
7 * Copyright (C) 2009-2010 Texas Instruments
8 * Author: Raja Mani <raja_mani@ti.com>
9 * Pavan Savoy <pavan_savoy@ti.com>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 *
24 */
25
26#include <linux/platform_device.h>
27#include <net/bluetooth/bluetooth.h>
28#include <net/bluetooth/hci_core.h>
29#include <net/bluetooth/hci.h>
30
31#include <linux/ti_wilink_st.h>
32#include <linux/module.h>
33
34/* Bluetooth Driver Version */
35#define VERSION "1.0"
36#define MAX_BT_CHNL_IDS 3
37
38/* Number of seconds to wait for registration completion
39 * when ST returns PENDING status.
40 */
41#define BT_REGISTER_TIMEOUT 6000 /* 6 sec */
42
43/**
44 * struct ti_st - driver operation structure
45 * @hdev: hci device pointer which binds to bt driver
46 * @reg_status: ST registration callback status
47 * @st_write: write function provided by the ST driver
48 * to be used by the driver during send_frame.
49 * @wait_reg_completion - completion sync between ti_st_open
50 * and st_reg_completion_cb.
51 */
52struct ti_st {
53 struct hci_dev *hdev;
54 int reg_status;
55 long (*st_write) (struct sk_buff *);
56 struct completion wait_reg_completion;
57};
58
59/* Increments HCI counters based on pocket ID (cmd,acl,sco) */
60static inline void ti_st_tx_complete(struct ti_st *hst, int pkt_type)
61{
62 struct hci_dev *hdev = hst->hdev;
63
64 /* Update HCI stat counters */
65 switch (pkt_type) {
66 case HCI_COMMAND_PKT:
67 hdev->stat.cmd_tx++;
68 break;
69
70 case HCI_ACLDATA_PKT:
71 hdev->stat.acl_tx++;
72 break;
73
74 case HCI_SCODATA_PKT:
75 hdev->stat.sco_tx++;
76 break;
77 }
78}
79
80/* ------- Interfaces to Shared Transport ------ */
81
82/* Called by ST layer to indicate protocol registration completion
83 * status.ti_st_open() function will wait for signal from this
84 * API when st_register() function returns ST_PENDING.
85 */
86static void st_reg_completion_cb(void *priv_data, int data)
87{
88 struct ti_st *lhst = priv_data;
89
90 /* Save registration status for use in ti_st_open() */
91 lhst->reg_status = data;
92 /* complete the wait in ti_st_open() */
93 complete(&lhst->wait_reg_completion);
94}
95
96/* Called by Shared Transport layer when receive data is available */
97static long st_receive(void *priv_data, struct sk_buff *skb)
98{
99 struct ti_st *lhst = priv_data;
100 int err;
101
102 if (!skb)
103 return -EFAULT;
104
105 if (!lhst) {
106 kfree_skb(skb);
107 return -EFAULT;
108 }
109
110 /* Forward skb to HCI core layer */
111 err = hci_recv_frame(lhst->hdev, skb);
112 if (err < 0) {
113 BT_ERR("Unable to push skb to HCI core(%d)", err);
114 return err;
115 }
116
117 lhst->hdev->stat.byte_rx += skb->len;
118
119 return 0;
120}
121
122/* ------- Interfaces to HCI layer ------ */
123/* protocol structure registered with shared transport */
124static struct st_proto_s ti_st_proto[MAX_BT_CHNL_IDS] = {
125 {
126 .chnl_id = HCI_EVENT_PKT, /* HCI Events */
127 .hdr_len = sizeof(struct hci_event_hdr),
128 .offset_len_in_hdr = offsetof(struct hci_event_hdr, plen),
129 .len_size = 1, /* sizeof(plen) in struct hci_event_hdr */
130 .reserve = 8,
131 },
132 {
133 .chnl_id = HCI_ACLDATA_PKT, /* ACL */
134 .hdr_len = sizeof(struct hci_acl_hdr),
135 .offset_len_in_hdr = offsetof(struct hci_acl_hdr, dlen),
136 .len_size = 2, /* sizeof(dlen) in struct hci_acl_hdr */
137 .reserve = 8,
138 },
139 {
140 .chnl_id = HCI_SCODATA_PKT, /* SCO */
141 .hdr_len = sizeof(struct hci_sco_hdr),
142 .offset_len_in_hdr = offsetof(struct hci_sco_hdr, dlen),
143 .len_size = 1, /* sizeof(dlen) in struct hci_sco_hdr */
144 .reserve = 8,
145 },
146};
147
148/* Called from HCI core to initialize the device */
149static int ti_st_open(struct hci_dev *hdev)
150{
151 unsigned long timeleft;
152 struct ti_st *hst;
153 int err, i;
154
155 BT_DBG("%s %p", hdev->name, hdev);
156
157 /* provide contexts for callbacks from ST */
158 hst = hci_get_drvdata(hdev);
159
160 for (i = 0; i < MAX_BT_CHNL_IDS; i++) {
161 ti_st_proto[i].priv_data = hst;
162 ti_st_proto[i].max_frame_size = HCI_MAX_FRAME_SIZE;
163 ti_st_proto[i].recv = st_receive;
164 ti_st_proto[i].reg_complete_cb = st_reg_completion_cb;
165
166 /* Prepare wait-for-completion handler */
167 init_completion(&hst->wait_reg_completion);
168 /* Reset ST registration callback status flag,
169 * this value will be updated in
170 * st_reg_completion_cb()
171 * function whenever it called from ST driver.
172 */
173 hst->reg_status = -EINPROGRESS;
174
175 err = st_register(&ti_st_proto[i]);
176 if (!err)
177 goto done;
178
179 if (err != -EINPROGRESS) {
180 BT_ERR("st_register failed %d", err);
181 return err;
182 }
183
184 /* ST is busy with either protocol
185 * registration or firmware download.
186 */
187 BT_DBG("waiting for registration "
188 "completion signal from ST");
189 timeleft = wait_for_completion_timeout
190 (&hst->wait_reg_completion,
191 msecs_to_jiffies(BT_REGISTER_TIMEOUT));
192 if (!timeleft) {
193 BT_ERR("Timeout(%d sec),didn't get reg "
194 "completion signal from ST",
195 BT_REGISTER_TIMEOUT / 1000);
196 return -ETIMEDOUT;
197 }
198
199 /* Is ST registration callback
200 * called with ERROR status?
201 */
202 if (hst->reg_status != 0) {
203 BT_ERR("ST registration completed with invalid "
204 "status %d", hst->reg_status);
205 return -EAGAIN;
206 }
207
208done:
209 hst->st_write = ti_st_proto[i].write;
210 if (!hst->st_write) {
211 BT_ERR("undefined ST write function");
212 for (i = 0; i < MAX_BT_CHNL_IDS; i++) {
213 /* Undo registration with ST */
214 err = st_unregister(&ti_st_proto[i]);
215 if (err)
216 BT_ERR("st_unregister() failed with "
217 "error %d", err);
218 hst->st_write = NULL;
219 }
220 return -EIO;
221 }
222 }
223 return 0;
224}
225
226/* Close device */
227static int ti_st_close(struct hci_dev *hdev)
228{
229 int err, i;
230 struct ti_st *hst = hci_get_drvdata(hdev);
231
232 for (i = MAX_BT_CHNL_IDS-1; i >= 0; i--) {
233 err = st_unregister(&ti_st_proto[i]);
234 if (err)
235 BT_ERR("st_unregister(%d) failed with error %d",
236 ti_st_proto[i].chnl_id, err);
237 }
238
239 hst->st_write = NULL;
240
241 return err;
242}
243
244static int ti_st_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
245{
246 struct ti_st *hst;
247 long len;
248 int pkt_type;
249
250 hst = hci_get_drvdata(hdev);
251
252 /* Prepend skb with frame type */
253 memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
254
255 BT_DBG("%s: type %d len %d", hdev->name, hci_skb_pkt_type(skb),
256 skb->len);
257
258 /* Insert skb to shared transport layer's transmit queue.
259 * Freeing skb memory is taken care in shared transport layer,
260 * so don't free skb memory here.
261 */
262 pkt_type = hci_skb_pkt_type(skb);
263 len = hst->st_write(skb);
264 if (len < 0) {
265 BT_ERR("ST write failed (%ld)", len);
266 /* Try Again, would only fail if UART has gone bad */
267 return -EAGAIN;
268 }
269
270 /* ST accepted our skb. So, Go ahead and do rest */
271 hdev->stat.byte_tx += len;
272 ti_st_tx_complete(hst, pkt_type);
273
274 return 0;
275}
276
277static int bt_ti_probe(struct platform_device *pdev)
278{
279 struct ti_st *hst;
280 struct hci_dev *hdev;
281 int err;
282
283 hst = devm_kzalloc(&pdev->dev, sizeof(struct ti_st), GFP_KERNEL);
284 if (!hst)
285 return -ENOMEM;
286
287 /* Expose "hciX" device to user space */
288 hdev = hci_alloc_dev();
289 if (!hdev)
290 return -ENOMEM;
291
292 BT_DBG("hdev %p", hdev);
293
294 hst->hdev = hdev;
295 hdev->bus = HCI_UART;
296 hci_set_drvdata(hdev, hst);
297 hdev->open = ti_st_open;
298 hdev->close = ti_st_close;
299 hdev->flush = NULL;
300 hdev->send = ti_st_send_frame;
301
302 err = hci_register_dev(hdev);
303 if (err < 0) {
304 BT_ERR("Can't register HCI device error %d", err);
305 hci_free_dev(hdev);
306 return err;
307 }
308
309 BT_DBG("HCI device registered (hdev %p)", hdev);
310
311 dev_set_drvdata(&pdev->dev, hst);
312 return 0;
313}
314
315static int bt_ti_remove(struct platform_device *pdev)
316{
317 struct hci_dev *hdev;
318 struct ti_st *hst = dev_get_drvdata(&pdev->dev);
319
320 if (!hst)
321 return -EFAULT;
322
323 BT_DBG("%s", hst->hdev->name);
324
325 hdev = hst->hdev;
326 ti_st_close(hdev);
327 hci_unregister_dev(hdev);
328
329 hci_free_dev(hdev);
330
331 dev_set_drvdata(&pdev->dev, NULL);
332 return 0;
333}
334
335static struct platform_driver btwilink_driver = {
336 .probe = bt_ti_probe,
337 .remove = bt_ti_remove,
338 .driver = {
339 .name = "btwilink",
340 },
341};
342
343module_platform_driver(btwilink_driver);
344
345/* ------ Module Info ------ */
346
347MODULE_AUTHOR("Raja Mani <raja_mani@ti.com>");
348MODULE_DESCRIPTION("Bluetooth Driver for TI Shared Transport" VERSION);
349MODULE_VERSION(VERSION);
350MODULE_LICENSE("GPL");
351