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 #define DEBUG
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 */
52 struct ti_st {
53 struct hci_dev *hdev;
54 char 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) */
ti_st_tx_complete(struct ti_st * hst,int pkt_type)60 static 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 */
st_reg_completion_cb(void * priv_data,char data)86 static void st_reg_completion_cb(void *priv_data, char 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
97 * available */
st_receive(void * priv_data,struct sk_buff * skb)98 static long st_receive(void *priv_data, struct sk_buff *skb)
99 {
100 struct ti_st *lhst = priv_data;
101 int err;
102
103 if (!skb)
104 return -EFAULT;
105
106 if (!lhst) {
107 kfree_skb(skb);
108 return -EFAULT;
109 }
110
111 /* Forward skb to HCI core layer */
112 err = hci_recv_frame(lhst->hdev, skb);
113 if (err < 0) {
114 BT_ERR("Unable to push skb to HCI core(%d)", err);
115 return err;
116 }
117
118 lhst->hdev->stat.byte_rx += skb->len;
119
120 return 0;
121 }
122
123 /* ------- Interfaces to HCI layer ------ */
124 /* protocol structure registered with shared transport */
125 static struct st_proto_s ti_st_proto[MAX_BT_CHNL_IDS] = {
126 {
127 .chnl_id = HCI_EVENT_PKT, /* HCI Events */
128 .hdr_len = sizeof(struct hci_event_hdr),
129 .offset_len_in_hdr = offsetof(struct hci_event_hdr, plen),
130 .len_size = 1, /* sizeof(plen) in struct hci_event_hdr */
131 .reserve = 8,
132 },
133 {
134 .chnl_id = HCI_ACLDATA_PKT, /* ACL */
135 .hdr_len = sizeof(struct hci_acl_hdr),
136 .offset_len_in_hdr = offsetof(struct hci_acl_hdr, dlen),
137 .len_size = 2, /* sizeof(dlen) in struct hci_acl_hdr */
138 .reserve = 8,
139 },
140 {
141 .chnl_id = HCI_SCODATA_PKT, /* SCO */
142 .hdr_len = sizeof(struct hci_sco_hdr),
143 .offset_len_in_hdr = offsetof(struct hci_sco_hdr, dlen),
144 .len_size = 1, /* sizeof(dlen) in struct hci_sco_hdr */
145 .reserve = 8,
146 },
147 };
148
149 /* Called from HCI core to initialize the device */
ti_st_open(struct hci_dev * hdev)150 static int ti_st_open(struct hci_dev *hdev)
151 {
152 unsigned long timeleft;
153 struct ti_st *hst;
154 int err, i;
155
156 BT_DBG("%s %p", hdev->name, hdev);
157
158 if (test_and_set_bit(HCI_RUNNING, &hdev->flags))
159 return -EBUSY;
160
161 /* provide contexts for callbacks from ST */
162 hst = hci_get_drvdata(hdev);
163
164 for (i = 0; i < MAX_BT_CHNL_IDS; i++) {
165 ti_st_proto[i].priv_data = hst;
166 ti_st_proto[i].max_frame_size = HCI_MAX_FRAME_SIZE;
167 ti_st_proto[i].recv = st_receive;
168 ti_st_proto[i].reg_complete_cb = st_reg_completion_cb;
169
170 /* Prepare wait-for-completion handler */
171 init_completion(&hst->wait_reg_completion);
172 /* Reset ST registration callback status flag,
173 * this value will be updated in
174 * st_reg_completion_cb()
175 * function whenever it called from ST driver.
176 */
177 hst->reg_status = -EINPROGRESS;
178
179 err = st_register(&ti_st_proto[i]);
180 if (!err)
181 goto done;
182
183 if (err != -EINPROGRESS) {
184 clear_bit(HCI_RUNNING, &hdev->flags);
185 BT_ERR("st_register failed %d", err);
186 return err;
187 }
188
189 /* ST is busy with either protocol
190 * registration or firmware download.
191 */
192 BT_DBG("waiting for registration "
193 "completion signal from ST");
194 timeleft = wait_for_completion_timeout
195 (&hst->wait_reg_completion,
196 msecs_to_jiffies(BT_REGISTER_TIMEOUT));
197 if (!timeleft) {
198 clear_bit(HCI_RUNNING, &hdev->flags);
199 BT_ERR("Timeout(%d sec),didn't get reg "
200 "completion signal from ST",
201 BT_REGISTER_TIMEOUT / 1000);
202 return -ETIMEDOUT;
203 }
204
205 /* Is ST registration callback
206 * called with ERROR status? */
207 if (hst->reg_status != 0) {
208 clear_bit(HCI_RUNNING, &hdev->flags);
209 BT_ERR("ST registration completed with invalid "
210 "status %d", hst->reg_status);
211 return -EAGAIN;
212 }
213
214 done:
215 hst->st_write = ti_st_proto[i].write;
216 if (!hst->st_write) {
217 BT_ERR("undefined ST write function");
218 clear_bit(HCI_RUNNING, &hdev->flags);
219 for (i = 0; i < MAX_BT_CHNL_IDS; i++) {
220 /* Undo registration with ST */
221 err = st_unregister(&ti_st_proto[i]);
222 if (err)
223 BT_ERR("st_unregister() failed with "
224 "error %d", err);
225 hst->st_write = NULL;
226 }
227 return -EIO;
228 }
229 }
230 return 0;
231 }
232
233 /* Close device */
ti_st_close(struct hci_dev * hdev)234 static int ti_st_close(struct hci_dev *hdev)
235 {
236 int err, i;
237 struct ti_st *hst = hci_get_drvdata(hdev);
238
239 if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
240 return 0;
241
242 for (i = MAX_BT_CHNL_IDS-1; i >= 0; i--) {
243 err = st_unregister(&ti_st_proto[i]);
244 if (err)
245 BT_ERR("st_unregister(%d) failed with error %d",
246 ti_st_proto[i].chnl_id, err);
247 }
248
249 hst->st_write = NULL;
250
251 return err;
252 }
253
ti_st_send_frame(struct hci_dev * hdev,struct sk_buff * skb)254 static int ti_st_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
255 {
256 struct ti_st *hst;
257 long len;
258
259 if (!test_bit(HCI_RUNNING, &hdev->flags))
260 return -EBUSY;
261
262 hst = hci_get_drvdata(hdev);
263
264 /* Prepend skb with frame type */
265 memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
266
267 BT_DBG("%s: type %d len %d", hdev->name, bt_cb(skb)->pkt_type,
268 skb->len);
269
270 /* Insert skb to shared transport layer's transmit queue.
271 * Freeing skb memory is taken care in shared transport layer,
272 * so don't free skb memory here.
273 */
274 len = hst->st_write(skb);
275 if (len < 0) {
276 kfree_skb(skb);
277 BT_ERR("ST write failed (%ld)", len);
278 /* Try Again, would only fail if UART has gone bad */
279 return -EAGAIN;
280 }
281
282 /* ST accepted our skb. So, Go ahead and do rest */
283 hdev->stat.byte_tx += len;
284 ti_st_tx_complete(hst, bt_cb(skb)->pkt_type);
285
286 return 0;
287 }
288
bt_ti_probe(struct platform_device * pdev)289 static int bt_ti_probe(struct platform_device *pdev)
290 {
291 static struct ti_st *hst;
292 struct hci_dev *hdev;
293 int err;
294
295 hst = devm_kzalloc(&pdev->dev, sizeof(struct ti_st), GFP_KERNEL);
296 if (!hst)
297 return -ENOMEM;
298
299 /* Expose "hciX" device to user space */
300 hdev = hci_alloc_dev();
301 if (!hdev)
302 return -ENOMEM;
303
304 BT_DBG("hdev %p", hdev);
305
306 hst->hdev = hdev;
307 hdev->bus = HCI_UART;
308 hci_set_drvdata(hdev, hst);
309 hdev->open = ti_st_open;
310 hdev->close = ti_st_close;
311 hdev->flush = NULL;
312 hdev->send = ti_st_send_frame;
313
314 err = hci_register_dev(hdev);
315 if (err < 0) {
316 BT_ERR("Can't register HCI device error %d", err);
317 hci_free_dev(hdev);
318 return err;
319 }
320
321 BT_DBG("HCI device registered (hdev %p)", hdev);
322
323 dev_set_drvdata(&pdev->dev, hst);
324 return err;
325 }
326
bt_ti_remove(struct platform_device * pdev)327 static int bt_ti_remove(struct platform_device *pdev)
328 {
329 struct hci_dev *hdev;
330 struct ti_st *hst = dev_get_drvdata(&pdev->dev);
331
332 if (!hst)
333 return -EFAULT;
334
335 BT_DBG("%s", hst->hdev->name);
336
337 hdev = hst->hdev;
338 ti_st_close(hdev);
339 hci_unregister_dev(hdev);
340
341 hci_free_dev(hdev);
342
343 dev_set_drvdata(&pdev->dev, NULL);
344 return 0;
345 }
346
347 static struct platform_driver btwilink_driver = {
348 .probe = bt_ti_probe,
349 .remove = bt_ti_remove,
350 .driver = {
351 .name = "btwilink",
352 .owner = THIS_MODULE,
353 },
354 };
355
356 module_platform_driver(btwilink_driver);
357
358 /* ------ Module Info ------ */
359
360 MODULE_AUTHOR("Raja Mani <raja_mani@ti.com>");
361 MODULE_DESCRIPTION("Bluetooth Driver for TI Shared Transport" VERSION);
362 MODULE_VERSION(VERSION);
363 MODULE_LICENSE("GPL");
364