Linux kernel & device driver programming

Cross-Referenced Linux and Device Driver Code

[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ]
Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  1 /*
  2  *
  3  *  Generic Bluetooth SDIO driver
  4  *
  5  *  Copyright (C) 2007  Cambridge Silicon Radio Ltd.
  6  *  Copyright (C) 2007  Marcel Holtmann <marcel@holtmann.org>
  7  *
  8  *
  9  *  This program is free software; you can redistribute it and/or modify
 10  *  it under the terms of the GNU General Public License as published by
 11  *  the Free Software Foundation; either version 2 of the License, or
 12  *  (at your option) any later version.
 13  *
 14  *  This program is distributed in the hope that it will be useful,
 15  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 17  *  GNU General Public License for more details.
 18  *
 19  *  You should have received a copy of the GNU General Public License
 20  *  along with this program; if not, write to the Free Software
 21  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 22  *
 23  */
 24 
 25 #include <linux/kernel.h>
 26 #include <linux/module.h>
 27 #include <linux/init.h>
 28 #include <linux/slab.h>
 29 #include <linux/types.h>
 30 #include <linux/sched.h>
 31 #include <linux/errno.h>
 32 #include <linux/skbuff.h>
 33 
 34 #include <linux/mmc/sdio_ids.h>
 35 #include <linux/mmc/sdio_func.h>
 36 
 37 #include <net/bluetooth/bluetooth.h>
 38 #include <net/bluetooth/hci_core.h>
 39 
 40 #ifndef CONFIG_BT_HCIBTSDIO_DEBUG
 41 #undef  BT_DBG
 42 #define BT_DBG(D...)
 43 #endif
 44 
 45 #define VERSION "0.1"
 46 
 47 static const struct sdio_device_id btsdio_table[] = {
 48         /* Generic Bluetooth Type-A SDIO device */
 49         { SDIO_DEVICE_CLASS(SDIO_CLASS_BT_A) },
 50 
 51         /* Generic Bluetooth Type-B SDIO device */
 52         { SDIO_DEVICE_CLASS(SDIO_CLASS_BT_B) },
 53 
 54         { }     /* Terminating entry */
 55 };
 56 
 57 MODULE_DEVICE_TABLE(sdio, btsdio_table);
 58 
 59 struct btsdio_data {
 60         struct hci_dev   *hdev;
 61         struct sdio_func *func;
 62 
 63         struct work_struct work;
 64 
 65         struct sk_buff_head txq;
 66 };
 67 
 68 #define REG_RDAT     0x00       /* Receiver Data */
 69 #define REG_TDAT     0x00       /* Transmitter Data */
 70 #define REG_PC_RRT   0x10       /* Read Packet Control */
 71 #define REG_PC_WRT   0x11       /* Write Packet Control */
 72 #define REG_RTC_STAT 0x12       /* Retry Control Status */
 73 #define REG_RTC_SET  0x12       /* Retry Control Set */
 74 #define REG_INTRD    0x13       /* Interrupt Indication */
 75 #define REG_CL_INTRD 0x13       /* Interrupt Clear */
 76 #define REG_EN_INTRD 0x14       /* Interrupt Enable */
 77 #define REG_MD_STAT  0x20       /* Bluetooth Mode Status */
 78 
 79 static int btsdio_tx_packet(struct btsdio_data *data, struct sk_buff *skb)
 80 {
 81         int err;
 82 
 83         BT_DBG("%s", data->hdev->name);
 84 
 85         /* Prepend Type-A header */
 86         skb_push(skb, 4);
 87         skb->data[0] = (skb->len & 0x0000ff);
 88         skb->data[1] = (skb->len & 0x00ff00) >> 8;
 89         skb->data[2] = (skb->len & 0xff0000) >> 16;
 90         skb->data[3] = bt_cb(skb)->pkt_type;
 91 
 92         err = sdio_writesb(data->func, REG_TDAT, skb->data, skb->len);
 93         if (err < 0) {
 94                 sdio_writeb(data->func, 0x01, REG_PC_WRT, NULL);
 95                 return err;
 96         }
 97 
 98         data->hdev->stat.byte_tx += skb->len;
 99 
100         kfree_skb(skb);
101 
102         return 0;
103 }
104 
105 static void btsdio_work(struct work_struct *work)
106 {
107         struct btsdio_data *data = container_of(work, struct btsdio_data, work);
108         struct sk_buff *skb;
109         int err;
110 
111         BT_DBG("%s", data->hdev->name);
112 
113         sdio_claim_host(data->func);
114 
115         while ((skb = skb_dequeue(&data->txq))) {
116                 err = btsdio_tx_packet(data, skb);
117                 if (err < 0) {
118                         data->hdev->stat.err_tx++;
119                         skb_queue_head(&data->txq, skb);
120                         break;
121                 }
122         }
123 
124         sdio_release_host(data->func);
125 }
126 
127 static int btsdio_rx_packet(struct btsdio_data *data)
128 {
129         u8 hdr[4] __attribute__ ((aligned(4)));
130         struct sk_buff *skb;
131         int err, len;
132 
133         BT_DBG("%s", data->hdev->name);
134 
135         err = sdio_readsb(data->func, hdr, REG_RDAT, 4);
136         if (err < 0)
137                 return err;
138 
139         len = hdr[0] | (hdr[1] << 8) | (hdr[2] << 16);
140         if (len < 4 || len > 65543)
141                 return -EILSEQ;
142 
143         skb = bt_skb_alloc(len - 4, GFP_KERNEL);
144         if (!skb) {
145                 /* Out of memory. Prepare a read retry and just
146                  * return with the expectation that the next time
147                  * we're called we'll have more memory. */
148                 return -ENOMEM;
149         }
150 
151         skb_put(skb, len - 4);
152 
153         err = sdio_readsb(data->func, skb->data, REG_RDAT, len - 4);
154         if (err < 0) {
155                 kfree(skb);
156                 return err;
157         }
158 
159         data->hdev->stat.byte_rx += len;
160 
161         skb->dev = (void *) data->hdev;
162         bt_cb(skb)->pkt_type = hdr[3];
163 
164         err = hci_recv_frame(skb);
165         if (err < 0)
166                 return err;
167 
168         sdio_writeb(data->func, 0x00, REG_PC_RRT, NULL);
169 
170         return 0;
171 }
172 
173 static void btsdio_interrupt(struct sdio_func *func)
174 {
175         struct btsdio_data *data = sdio_get_drvdata(func);
176         int intrd;
177 
178         BT_DBG("%s", data->hdev->name);
179 
180         intrd = sdio_readb(func, REG_INTRD, NULL);
181         if (intrd & 0x01) {
182                 sdio_writeb(func, 0x01, REG_CL_INTRD, NULL);
183 
184                 if (btsdio_rx_packet(data) < 0) {
185                         data->hdev->stat.err_rx++;
186                         sdio_writeb(data->func, 0x01, REG_PC_RRT, NULL);
187                 }
188         }
189 }
190 
191 static int btsdio_open(struct hci_dev *hdev)
192 {
193         struct btsdio_data *data = hdev->driver_data;
194         int err;
195 
196         BT_DBG("%s", hdev->name);
197 
198         if (test_and_set_bit(HCI_RUNNING, &hdev->flags))
199                 return 0;
200 
201         sdio_claim_host(data->func);
202 
203         err = sdio_enable_func(data->func);
204         if (err < 0) {
205                 clear_bit(HCI_RUNNING, &hdev->flags);
206                 goto release;
207         }
208 
209         err = sdio_claim_irq(data->func, btsdio_interrupt);
210         if (err < 0) {
211                 sdio_disable_func(data->func);
212                 clear_bit(HCI_RUNNING, &hdev->flags);
213                 goto release;
214         }
215 
216         if (data->func->class == SDIO_CLASS_BT_B)
217                 sdio_writeb(data->func, 0x00, REG_MD_STAT, NULL);
218 
219         sdio_writeb(data->func, 0x01, REG_EN_INTRD, NULL);
220 
221 release:
222         sdio_release_host(data->func);
223 
224         return err;
225 }
226 
227 static int btsdio_close(struct hci_dev *hdev)
228 {
229         struct btsdio_data *data = hdev->driver_data;
230 
231         BT_DBG("%s", hdev->name);
232 
233         if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
234                 return 0;
235 
236         sdio_claim_host(data->func);
237 
238         sdio_writeb(data->func, 0x00, REG_EN_INTRD, NULL);
239 
240         sdio_release_irq(data->func);
241         sdio_disable_func(data->func);
242 
243         sdio_release_host(data->func);
244 
245         return 0;
246 }
247 
248 static int btsdio_flush(struct hci_dev *hdev)
249 {
250         struct btsdio_data *data = hdev->driver_data;
251 
252         BT_DBG("%s", hdev->name);
253 
254         skb_queue_purge(&data->txq);
255 
256         return 0;
257 }
258 
259 static int btsdio_send_frame(struct sk_buff *skb)
260 {
261         struct hci_dev *hdev = (struct hci_dev *) skb->dev;
262         struct btsdio_data *data = hdev->driver_data;
263 
264         BT_DBG("%s", hdev->name);
265 
266         if (!test_bit(HCI_RUNNING, &hdev->flags))
267                 return -EBUSY;
268 
269         switch (bt_cb(skb)->pkt_type) {
270         case HCI_COMMAND_PKT:
271                 hdev->stat.cmd_tx++;
272                 break;
273 
274         case HCI_ACLDATA_PKT:
275                 hdev->stat.acl_tx++;
276                 break;
277 
278         case HCI_SCODATA_PKT:
279                 hdev->stat.sco_tx++;
280                 break;
281 
282         default:
283                 return -EILSEQ;
284         }
285 
286         skb_queue_tail(&data->txq, skb);
287 
288         schedule_work(&data->work);
289 
290         return 0;
291 }
292 
293 static void btsdio_destruct(struct hci_dev *hdev)
294 {
295         struct btsdio_data *data = hdev->driver_data;
296 
297         BT_DBG("%s", hdev->name);
298 
299         kfree(data);
300 }
301 
302 static int btsdio_probe(struct sdio_func *func,
303                                 const struct sdio_device_id *id)
304 {
305         struct btsdio_data *data;
306         struct hci_dev *hdev;
307         struct sdio_func_tuple *tuple = func->tuples;
308         int err;
309 
310         BT_DBG("func %p id %p class 0x%04x", func, id, func->class);
311 
312         while (tuple) {
313                 BT_DBG("code 0x%x size %d", tuple->code, tuple->size);
314                 tuple = tuple->next;
315         }
316 
317         data = kzalloc(sizeof(*data), GFP_KERNEL);
318         if (!data)
319                 return -ENOMEM;
320 
321         data->func = func;
322 
323         INIT_WORK(&data->work, btsdio_work);
324 
325         skb_queue_head_init(&data->txq);
326 
327         hdev = hci_alloc_dev();
328         if (!hdev) {
329                 kfree(data);
330                 return -ENOMEM;
331         }
332 
333         hdev->type = HCI_SDIO;
334         hdev->driver_data = data;
335 
336         data->hdev = hdev;
337 
338         SET_HCIDEV_DEV(hdev, &func->dev);
339 
340         hdev->open     = btsdio_open;
341         hdev->close    = btsdio_close;
342         hdev->flush    = btsdio_flush;
343         hdev->send     = btsdio_send_frame;
344         hdev->destruct = btsdio_destruct;
345 
346         hdev->owner = THIS_MODULE;
347 
348         err = hci_register_dev(hdev);
349         if (err < 0) {
350                 hci_free_dev(hdev);
351                 kfree(data);
352                 return err;
353         }
354 
355         sdio_set_drvdata(func, data);
356 
357         return 0;
358 }
359 
360 static void btsdio_remove(struct sdio_func *func)
361 {
362         struct btsdio_data *data = sdio_get_drvdata(func);
363         struct hci_dev *hdev;
364 
365         BT_DBG("func %p", func);
366 
367         if (!data)
368                 return;
369 
370         hdev = data->hdev;
371 
372         sdio_set_drvdata(func, NULL);
373 
374         hci_unregister_dev(hdev);
375 
376         hci_free_dev(hdev);
377 }
378 
379 static struct sdio_driver btsdio_driver = {
380         .name           = "btsdio",
381         .probe          = btsdio_probe,
382         .remove         = btsdio_remove,
383         .id_table       = btsdio_table,
384 };
385 
386 static int __init btsdio_init(void)
387 {
388         BT_INFO("Generic Bluetooth SDIO driver ver %s", VERSION);
389 
390         return sdio_register_driver(&btsdio_driver);
391 }
392 
393 static void __exit btsdio_exit(void)
394 {
395         sdio_unregister_driver(&btsdio_driver);
396 }
397 
398 module_init(btsdio_init);
399 module_exit(btsdio_exit);
400 
401 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
402 MODULE_DESCRIPTION("Generic Bluetooth SDIO driver ver " VERSION);
403 MODULE_VERSION(VERSION);
404 MODULE_LICENSE("GPL");
405 
  This page was automatically generated by the LXR engine.