1 /*
2 Driver for SAA6588 RDS decoder
3
4 (c) 2005 Hans J. Koch
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
20
21
22 #include <linux/module.h>
23 #include <linux/kernel.h>
24 #include <linux/i2c.h>
25 #include <linux/types.h>
26 #include <linux/videodev2.h>
27 #include <linux/init.h>
28 #include <linux/errno.h>
29 #include <linux/slab.h>
30 #include <linux/poll.h>
31 #include <linux/wait.h>
32 #include <linux/uaccess.h>
33
34 #include <media/i2c/saa6588.h>
35 #include <media/v4l2-device.h>
36
37
38 /* insmod options */
39 static unsigned int debug;
40 static unsigned int xtal;
41 static unsigned int mmbs;
42 static unsigned int plvl;
43 static unsigned int bufblocks = 100;
44
45 module_param(debug, int, 0644);
46 MODULE_PARM_DESC(debug, "enable debug messages");
47 module_param(xtal, int, 0);
48 MODULE_PARM_DESC(xtal, "select oscillator frequency (0..3), default 0");
49 module_param(mmbs, int, 0);
50 MODULE_PARM_DESC(mmbs, "enable MMBS mode: 0=off (default), 1=on");
51 module_param(plvl, int, 0);
52 MODULE_PARM_DESC(plvl, "select pause level (0..3), default 0");
53 module_param(bufblocks, int, 0);
54 MODULE_PARM_DESC(bufblocks, "number of buffered blocks, default 100");
55
56 MODULE_DESCRIPTION("v4l2 driver module for SAA6588 RDS decoder");
57 MODULE_AUTHOR("Hans J. Koch <koch@hjk-az.de>");
58
59 MODULE_LICENSE("GPL");
60
61 /* ---------------------------------------------------------------------- */
62
63 #define UNSET (-1U)
64 #define PREFIX "saa6588: "
65 #define dprintk if (debug) printk
66
67 struct saa6588 {
68 struct v4l2_subdev sd;
69 struct delayed_work work;
70 spinlock_t lock;
71 unsigned char *buffer;
72 unsigned int buf_size;
73 unsigned int rd_index;
74 unsigned int wr_index;
75 unsigned int block_count;
76 unsigned char last_blocknum;
77 wait_queue_head_t read_queue;
78 int data_available_for_read;
79 u8 sync;
80 };
81
to_saa6588(struct v4l2_subdev * sd)82 static inline struct saa6588 *to_saa6588(struct v4l2_subdev *sd)
83 {
84 return container_of(sd, struct saa6588, sd);
85 }
86
87 /* ---------------------------------------------------------------------- */
88
89 /*
90 * SAA6588 defines
91 */
92
93 /* Initialization and mode control byte (0w) */
94
95 /* bit 0+1 (DAC0/DAC1) */
96 #define cModeStandard 0x00
97 #define cModeFastPI 0x01
98 #define cModeReducedRequest 0x02
99 #define cModeInvalid 0x03
100
101 /* bit 2 (RBDS) */
102 #define cProcessingModeRDS 0x00
103 #define cProcessingModeRBDS 0x04
104
105 /* bit 3+4 (SYM0/SYM1) */
106 #define cErrCorrectionNone 0x00
107 #define cErrCorrection2Bits 0x08
108 #define cErrCorrection5Bits 0x10
109 #define cErrCorrectionNoneRBDS 0x18
110
111 /* bit 5 (NWSY) */
112 #define cSyncNormal 0x00
113 #define cSyncRestart 0x20
114
115 /* bit 6 (TSQD) */
116 #define cSigQualityDetectOFF 0x00
117 #define cSigQualityDetectON 0x40
118
119 /* bit 7 (SQCM) */
120 #define cSigQualityTriggered 0x00
121 #define cSigQualityContinous 0x80
122
123 /* Pause level and flywheel control byte (1w) */
124
125 /* bits 0..5 (FEB0..FEB5) */
126 #define cFlywheelMaxBlocksMask 0x3F
127 #define cFlywheelDefault 0x20
128
129 /* bits 6+7 (PL0/PL1) */
130 #define cPauseLevel_11mV 0x00
131 #define cPauseLevel_17mV 0x40
132 #define cPauseLevel_27mV 0x80
133 #define cPauseLevel_43mV 0xC0
134
135 /* Pause time/oscillator frequency/quality detector control byte (1w) */
136
137 /* bits 0..4 (SQS0..SQS4) */
138 #define cQualityDetectSensMask 0x1F
139 #define cQualityDetectDefault 0x0F
140
141 /* bit 5 (SOSC) */
142 #define cSelectOscFreqOFF 0x00
143 #define cSelectOscFreqON 0x20
144
145 /* bit 6+7 (PTF0/PTF1) */
146 #define cOscFreq_4332kHz 0x00
147 #define cOscFreq_8664kHz 0x40
148 #define cOscFreq_12996kHz 0x80
149 #define cOscFreq_17328kHz 0xC0
150
151 /* ---------------------------------------------------------------------- */
152
block_from_buf(struct saa6588 * s,unsigned char * buf)153 static bool block_from_buf(struct saa6588 *s, unsigned char *buf)
154 {
155 int i;
156
157 if (s->rd_index == s->wr_index) {
158 if (debug > 2)
159 dprintk(PREFIX "Read: buffer empty.\n");
160 return false;
161 }
162
163 if (debug > 2) {
164 dprintk(PREFIX "Read: ");
165 for (i = s->rd_index; i < s->rd_index + 3; i++)
166 dprintk("0x%02x ", s->buffer[i]);
167 }
168
169 memcpy(buf, &s->buffer[s->rd_index], 3);
170
171 s->rd_index += 3;
172 if (s->rd_index >= s->buf_size)
173 s->rd_index = 0;
174 s->block_count--;
175
176 if (debug > 2)
177 dprintk("%d blocks total.\n", s->block_count);
178
179 return true;
180 }
181
read_from_buf(struct saa6588 * s,struct saa6588_command * a)182 static void read_from_buf(struct saa6588 *s, struct saa6588_command *a)
183 {
184 unsigned char __user *buf_ptr = a->buffer;
185 unsigned char buf[3];
186 unsigned long flags;
187 unsigned int rd_blocks;
188 unsigned int i;
189
190 a->result = 0;
191 if (!a->buffer)
192 return;
193
194 while (!a->nonblocking && !s->data_available_for_read) {
195 int ret = wait_event_interruptible(s->read_queue,
196 s->data_available_for_read);
197 if (ret == -ERESTARTSYS) {
198 a->result = -EINTR;
199 return;
200 }
201 }
202
203 rd_blocks = a->block_count;
204 spin_lock_irqsave(&s->lock, flags);
205 if (rd_blocks > s->block_count)
206 rd_blocks = s->block_count;
207 spin_unlock_irqrestore(&s->lock, flags);
208
209 if (!rd_blocks)
210 return;
211
212 for (i = 0; i < rd_blocks; i++) {
213 bool got_block;
214
215 spin_lock_irqsave(&s->lock, flags);
216 got_block = block_from_buf(s, buf);
217 spin_unlock_irqrestore(&s->lock, flags);
218 if (!got_block)
219 break;
220 if (copy_to_user(buf_ptr, buf, 3)) {
221 a->result = -EFAULT;
222 return;
223 }
224 buf_ptr += 3;
225 a->result += 3;
226 }
227 spin_lock_irqsave(&s->lock, flags);
228 s->data_available_for_read = (s->block_count > 0);
229 spin_unlock_irqrestore(&s->lock, flags);
230 }
231
block_to_buf(struct saa6588 * s,unsigned char * blockbuf)232 static void block_to_buf(struct saa6588 *s, unsigned char *blockbuf)
233 {
234 unsigned int i;
235
236 if (debug > 3)
237 dprintk(PREFIX "New block: ");
238
239 for (i = 0; i < 3; ++i) {
240 if (debug > 3)
241 dprintk("0x%02x ", blockbuf[i]);
242 s->buffer[s->wr_index] = blockbuf[i];
243 s->wr_index++;
244 }
245
246 if (s->wr_index >= s->buf_size)
247 s->wr_index = 0;
248
249 if (s->wr_index == s->rd_index) {
250 s->rd_index += 3;
251 if (s->rd_index >= s->buf_size)
252 s->rd_index = 0;
253 } else
254 s->block_count++;
255
256 if (debug > 3)
257 dprintk("%d blocks total.\n", s->block_count);
258 }
259
saa6588_i2c_poll(struct saa6588 * s)260 static void saa6588_i2c_poll(struct saa6588 *s)
261 {
262 struct i2c_client *client = v4l2_get_subdevdata(&s->sd);
263 unsigned long flags;
264 unsigned char tmpbuf[6];
265 unsigned char blocknum;
266 unsigned char tmp;
267
268 /* Although we only need 3 bytes, we have to read at least 6.
269 SAA6588 returns garbage otherwise. */
270 if (6 != i2c_master_recv(client, &tmpbuf[0], 6)) {
271 if (debug > 1)
272 dprintk(PREFIX "read error!\n");
273 return;
274 }
275
276 s->sync = tmpbuf[0] & 0x10;
277 if (!s->sync)
278 return;
279 blocknum = tmpbuf[0] >> 5;
280 if (blocknum == s->last_blocknum) {
281 if (debug > 3)
282 dprintk("Saw block %d again.\n", blocknum);
283 return;
284 }
285
286 s->last_blocknum = blocknum;
287
288 /*
289 Byte order according to v4l2 specification:
290
291 Byte 0: Least Significant Byte of RDS Block
292 Byte 1: Most Significant Byte of RDS Block
293 Byte 2 Bit 7: Error bit. Indicates that an uncorrectable error
294 occurred during reception of this block.
295 Bit 6: Corrected bit. Indicates that an error was
296 corrected for this data block.
297 Bits 5-3: Same as bits 0-2.
298 Bits 2-0: Block number.
299
300 SAA6588 byte order is Status-MSB-LSB, so we have to swap the
301 first and the last of the 3 bytes block.
302 */
303
304 swap(tmpbuf[2], tmpbuf[0]);
305
306 /* Map 'Invalid block E' to 'Invalid Block' */
307 if (blocknum == 6)
308 blocknum = V4L2_RDS_BLOCK_INVALID;
309 /* And if are not in mmbs mode, then 'Block E' is also mapped
310 to 'Invalid Block'. As far as I can tell MMBS is discontinued,
311 and if there is ever a need to support E blocks, then please
312 contact the linux-media mailinglist. */
313 else if (!mmbs && blocknum == 5)
314 blocknum = V4L2_RDS_BLOCK_INVALID;
315 tmp = blocknum;
316 tmp |= blocknum << 3; /* Received offset == Offset Name (OK ?) */
317 if ((tmpbuf[2] & 0x03) == 0x03)
318 tmp |= V4L2_RDS_BLOCK_ERROR; /* uncorrectable error */
319 else if ((tmpbuf[2] & 0x03) != 0x00)
320 tmp |= V4L2_RDS_BLOCK_CORRECTED; /* corrected error */
321 tmpbuf[2] = tmp; /* Is this enough ? Should we also check other bits ? */
322
323 spin_lock_irqsave(&s->lock, flags);
324 block_to_buf(s, tmpbuf);
325 spin_unlock_irqrestore(&s->lock, flags);
326 s->data_available_for_read = 1;
327 wake_up_interruptible(&s->read_queue);
328 }
329
saa6588_work(struct work_struct * work)330 static void saa6588_work(struct work_struct *work)
331 {
332 struct saa6588 *s = container_of(work, struct saa6588, work.work);
333
334 saa6588_i2c_poll(s);
335 schedule_delayed_work(&s->work, msecs_to_jiffies(20));
336 }
337
saa6588_configure(struct saa6588 * s)338 static void saa6588_configure(struct saa6588 *s)
339 {
340 struct i2c_client *client = v4l2_get_subdevdata(&s->sd);
341 unsigned char buf[3];
342 int rc;
343
344 buf[0] = cSyncRestart;
345 if (mmbs)
346 buf[0] |= cProcessingModeRBDS;
347
348 buf[1] = cFlywheelDefault;
349 switch (plvl) {
350 case 0:
351 buf[1] |= cPauseLevel_11mV;
352 break;
353 case 1:
354 buf[1] |= cPauseLevel_17mV;
355 break;
356 case 2:
357 buf[1] |= cPauseLevel_27mV;
358 break;
359 case 3:
360 buf[1] |= cPauseLevel_43mV;
361 break;
362 default: /* nothing */
363 break;
364 }
365
366 buf[2] = cQualityDetectDefault | cSelectOscFreqON;
367
368 switch (xtal) {
369 case 0:
370 buf[2] |= cOscFreq_4332kHz;
371 break;
372 case 1:
373 buf[2] |= cOscFreq_8664kHz;
374 break;
375 case 2:
376 buf[2] |= cOscFreq_12996kHz;
377 break;
378 case 3:
379 buf[2] |= cOscFreq_17328kHz;
380 break;
381 default: /* nothing */
382 break;
383 }
384
385 dprintk(PREFIX "writing: 0w=0x%02x 1w=0x%02x 2w=0x%02x\n",
386 buf[0], buf[1], buf[2]);
387
388 rc = i2c_master_send(client, buf, 3);
389 if (rc != 3)
390 printk(PREFIX "i2c i/o error: rc == %d (should be 3)\n", rc);
391 }
392
393 /* ---------------------------------------------------------------------- */
394
saa6588_ioctl(struct v4l2_subdev * sd,unsigned int cmd,void * arg)395 static long saa6588_ioctl(struct v4l2_subdev *sd, unsigned int cmd, void *arg)
396 {
397 struct saa6588 *s = to_saa6588(sd);
398 struct saa6588_command *a = arg;
399
400 switch (cmd) {
401 /* --- close() for /dev/radio --- */
402 case SAA6588_CMD_CLOSE:
403 s->data_available_for_read = 1;
404 wake_up_interruptible(&s->read_queue);
405 s->data_available_for_read = 0;
406 a->result = 0;
407 break;
408 /* --- read() for /dev/radio --- */
409 case SAA6588_CMD_READ:
410 read_from_buf(s, a);
411 break;
412 /* --- poll() for /dev/radio --- */
413 case SAA6588_CMD_POLL:
414 a->poll_mask = 0;
415 if (s->data_available_for_read)
416 a->poll_mask |= EPOLLIN | EPOLLRDNORM;
417 poll_wait(a->instance, &s->read_queue, a->event_list);
418 break;
419
420 default:
421 /* nothing */
422 return -ENOIOCTLCMD;
423 }
424 return 0;
425 }
426
saa6588_g_tuner(struct v4l2_subdev * sd,struct v4l2_tuner * vt)427 static int saa6588_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *vt)
428 {
429 struct saa6588 *s = to_saa6588(sd);
430
431 vt->capability |= V4L2_TUNER_CAP_RDS | V4L2_TUNER_CAP_RDS_BLOCK_IO;
432 if (s->sync)
433 vt->rxsubchans |= V4L2_TUNER_SUB_RDS;
434 return 0;
435 }
436
saa6588_s_tuner(struct v4l2_subdev * sd,const struct v4l2_tuner * vt)437 static int saa6588_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *vt)
438 {
439 struct saa6588 *s = to_saa6588(sd);
440
441 saa6588_configure(s);
442 return 0;
443 }
444
445 /* ----------------------------------------------------------------------- */
446
447 static const struct v4l2_subdev_core_ops saa6588_core_ops = {
448 .ioctl = saa6588_ioctl,
449 };
450
451 static const struct v4l2_subdev_tuner_ops saa6588_tuner_ops = {
452 .g_tuner = saa6588_g_tuner,
453 .s_tuner = saa6588_s_tuner,
454 };
455
456 static const struct v4l2_subdev_ops saa6588_ops = {
457 .core = &saa6588_core_ops,
458 .tuner = &saa6588_tuner_ops,
459 };
460
461 /* ---------------------------------------------------------------------- */
462
saa6588_probe(struct i2c_client * client,const struct i2c_device_id * id)463 static int saa6588_probe(struct i2c_client *client,
464 const struct i2c_device_id *id)
465 {
466 struct saa6588 *s;
467 struct v4l2_subdev *sd;
468
469 v4l_info(client, "saa6588 found @ 0x%x (%s)\n",
470 client->addr << 1, client->adapter->name);
471
472 s = devm_kzalloc(&client->dev, sizeof(*s), GFP_KERNEL);
473 if (s == NULL)
474 return -ENOMEM;
475
476 s->buf_size = bufblocks * 3;
477
478 s->buffer = devm_kzalloc(&client->dev, s->buf_size, GFP_KERNEL);
479 if (s->buffer == NULL)
480 return -ENOMEM;
481 sd = &s->sd;
482 v4l2_i2c_subdev_init(sd, client, &saa6588_ops);
483 spin_lock_init(&s->lock);
484 s->block_count = 0;
485 s->wr_index = 0;
486 s->rd_index = 0;
487 s->last_blocknum = 0xff;
488 init_waitqueue_head(&s->read_queue);
489 s->data_available_for_read = 0;
490
491 saa6588_configure(s);
492
493 /* start polling via eventd */
494 INIT_DELAYED_WORK(&s->work, saa6588_work);
495 schedule_delayed_work(&s->work, 0);
496 return 0;
497 }
498
saa6588_remove(struct i2c_client * client)499 static int saa6588_remove(struct i2c_client *client)
500 {
501 struct v4l2_subdev *sd = i2c_get_clientdata(client);
502 struct saa6588 *s = to_saa6588(sd);
503
504 v4l2_device_unregister_subdev(sd);
505
506 cancel_delayed_work_sync(&s->work);
507
508 return 0;
509 }
510
511 /* ----------------------------------------------------------------------- */
512
513 static const struct i2c_device_id saa6588_id[] = {
514 { "saa6588", 0 },
515 { }
516 };
517 MODULE_DEVICE_TABLE(i2c, saa6588_id);
518
519 static struct i2c_driver saa6588_driver = {
520 .driver = {
521 .name = "saa6588",
522 },
523 .probe = saa6588_probe,
524 .remove = saa6588_remove,
525 .id_table = saa6588_id,
526 };
527
528 module_i2c_driver(saa6588_driver);
529
