a81285ca7d5bcbb98d54f8bb326536e064442815
[linux-3.10.git] / drivers / media / video / saa6588.c
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/videodev.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 <asm/uaccess.h>
33
34
35 #include <media/rds.h>
36
37 /* Addresses to scan */
38 static unsigned short normal_i2c[] = {
39         0x20 >> 1,
40         0x22 >> 1,
41         I2C_CLIENT_END,
42 };
43
44 I2C_CLIENT_INSMOD;
45
46 /* insmod options */
47 static unsigned int debug = 0;
48 static unsigned int xtal = 0;
49 static unsigned int rbds = 0;
50 static unsigned int plvl = 0;
51 static unsigned int bufblocks = 100;
52
53 module_param(debug, int, 0644);
54 MODULE_PARM_DESC(debug, "enable debug messages");
55 module_param(xtal, int, 0);
56 MODULE_PARM_DESC(xtal, "select oscillator frequency (0..3), default 0");
57 module_param(rbds, int, 0);
58 MODULE_PARM_DESC(rbds, "select mode, 0=RDS, 1=RBDS, default 0");
59 module_param(plvl, int, 0);
60 MODULE_PARM_DESC(plvl, "select pause level (0..3), default 0");
61 module_param(bufblocks, int, 0);
62 MODULE_PARM_DESC(bufblocks, "number of buffered blocks, default 100");
63
64 MODULE_DESCRIPTION("v4l2 driver module for SAA6588 RDS decoder");
65 MODULE_AUTHOR("Hans J. Koch <koch@hjk-az.de>");
66
67 MODULE_LICENSE("GPL");
68
69 /* ---------------------------------------------------------------------- */
70
71 #define UNSET       (-1U)
72 #define PREFIX      "saa6588: "
73 #define dprintk     if (debug) printk
74
75 struct saa6588 {
76         struct i2c_client client;
77         struct work_struct work;
78         struct timer_list timer;
79         spinlock_t lock;
80         unsigned char *buffer;
81         unsigned int buf_size;
82         unsigned int rd_index;
83         unsigned int wr_index;
84         unsigned int block_count;
85         unsigned char last_blocknum;
86         wait_queue_head_t read_queue;
87         int data_available_for_read;
88 };
89
90 static struct i2c_driver driver;
91 static struct i2c_client client_template;
92
93 /* ---------------------------------------------------------------------- */
94
95 /*
96  * SAA6588 defines
97  */
98
99 /* Initialization and mode control byte (0w) */
100
101 /* bit 0+1 (DAC0/DAC1) */
102 #define cModeStandard           0x00
103 #define cModeFastPI             0x01
104 #define cModeReducedRequest     0x02
105 #define cModeInvalid            0x03
106
107 /* bit 2 (RBDS) */
108 #define cProcessingModeRDS      0x00
109 #define cProcessingModeRBDS     0x04
110
111 /* bit 3+4 (SYM0/SYM1) */
112 #define cErrCorrectionNone      0x00
113 #define cErrCorrection2Bits     0x08
114 #define cErrCorrection5Bits     0x10
115 #define cErrCorrectionNoneRBDS  0x18
116
117 /* bit 5 (NWSY) */
118 #define cSyncNormal             0x00
119 #define cSyncRestart            0x20
120
121 /* bit 6 (TSQD) */
122 #define cSigQualityDetectOFF    0x00
123 #define cSigQualityDetectON     0x40
124
125 /* bit 7 (SQCM) */
126 #define cSigQualityTriggered    0x00
127 #define cSigQualityContinous    0x80
128
129 /* Pause level and flywheel control byte (1w) */
130
131 /* bits 0..5 (FEB0..FEB5) */
132 #define cFlywheelMaxBlocksMask  0x3F
133 #define cFlywheelDefault        0x20
134
135 /* bits 6+7 (PL0/PL1) */
136 #define cPauseLevel_11mV        0x00
137 #define cPauseLevel_17mV        0x40
138 #define cPauseLevel_27mV        0x80
139 #define cPauseLevel_43mV        0xC0
140
141 /* Pause time/oscillator frequency/quality detector control byte (1w) */
142
143 /* bits 0..4 (SQS0..SQS4) */
144 #define cQualityDetectSensMask  0x1F
145 #define cQualityDetectDefault   0x0F
146
147 /* bit 5 (SOSC) */
148 #define cSelectOscFreqOFF       0x00
149 #define cSelectOscFreqON        0x20
150
151 /* bit 6+7 (PTF0/PTF1) */
152 #define cOscFreq_4332kHz        0x00
153 #define cOscFreq_8664kHz        0x40
154 #define cOscFreq_12996kHz       0x80
155 #define cOscFreq_17328kHz       0xC0
156
157 /* ---------------------------------------------------------------------- */
158
159 static int block_to_user_buf(struct saa6588 *s, unsigned char __user *user_buf)
160 {
161         int i;
162
163         if (s->rd_index == s->wr_index) {
164                 if (debug > 2)
165                         dprintk(PREFIX "Read: buffer empty.\n");
166                 return 0;
167         }
168
169         if (debug > 2) {
170                 dprintk(PREFIX "Read: ");
171                 for (i = s->rd_index; i < s->rd_index + 3; i++)
172                         dprintk("0x%02x ", s->buffer[i]);
173         }
174
175         if (copy_to_user(user_buf, &s->buffer[s->rd_index], 3))
176                 return -EFAULT;
177
178         s->rd_index += 3;
179         if (s->rd_index >= s->buf_size)
180                 s->rd_index = 0;
181         s->block_count--;
182
183         if (debug > 2)
184                 dprintk("%d blocks total.\n", s->block_count);
185
186         return 1;
187 }
188
189 static void read_from_buf(struct saa6588 *s, struct rds_command *a)
190 {
191         unsigned long flags;
192
193         unsigned char __user *buf_ptr = a->buffer;
194         unsigned int i;
195         unsigned int rd_blocks;
196
197         a->result = 0;
198         if (!a->buffer)
199                 return;
200
201         while (!s->data_available_for_read) {
202                 int ret = wait_event_interruptible(s->read_queue,
203                                              s->data_available_for_read);
204                 if (ret == -ERESTARTSYS) {
205                         a->result = -EINTR;
206                         return;
207                 }
208         }
209
210         spin_lock_irqsave(&s->lock, flags);
211         rd_blocks = a->block_count;
212         if (rd_blocks > s->block_count)
213                 rd_blocks = s->block_count;
214
215         if (!rd_blocks)
216                 return;
217
218         for (i = 0; i < rd_blocks; i++) {
219                 if (block_to_user_buf(s, buf_ptr)) {
220                         buf_ptr += 3;
221                         a->result++;
222                 } else
223                         break;
224         }
225         a->result *= 3;
226         s->data_available_for_read = (s->block_count > 0);
227         spin_unlock_irqrestore(&s->lock, flags);
228 }
229
230 static void block_to_buf(struct saa6588 *s, unsigned char *blockbuf)
231 {
232         unsigned int i;
233
234         if (debug > 3)
235                 dprintk(PREFIX "New block: ");
236
237         for (i = 0; i < 3; ++i) {
238                 if (debug > 3)
239                         dprintk("0x%02x ", blockbuf[i]);
240                 s->buffer[s->wr_index] = blockbuf[i];
241                 s->wr_index++;
242         }
243
244         if (s->wr_index >= s->buf_size)
245                 s->wr_index = 0;
246
247         if (s->wr_index == s->rd_index) {
248                 s->rd_index += 3;
249                 if (s->rd_index >= s->buf_size)
250                         s->rd_index = 0;
251         } else
252                 s->block_count++;
253
254         if (debug > 3)
255                 dprintk("%d blocks total.\n", s->block_count);
256 }
257
258 static void saa6588_i2c_poll(struct saa6588 *s)
259 {
260         unsigned long flags;
261         unsigned char tmpbuf[6];
262         unsigned char blocknum;
263         unsigned char tmp;
264
265         /* Although we only need 3 bytes, we have to read at least 6.
266            SAA6588 returns garbage otherwise */
267         if (6 != i2c_master_recv(&s->client, &tmpbuf[0], 6)) {
268                 if (debug > 1)
269                         dprintk(PREFIX "read error!\n");
270                 return;
271         }
272
273         blocknum = tmpbuf[0] >> 5;
274         if (blocknum == s->last_blocknum) {
275                 if (debug > 3)
276                         dprintk("Saw block %d again.\n", blocknum);
277                 return;
278         }
279
280         s->last_blocknum = blocknum;
281
282         /*
283            Byte order according to v4l2 specification:
284
285            Byte 0: Least Significant Byte of RDS Block
286            Byte 1: Most Significant Byte of RDS Block
287            Byte 2 Bit 7: Error bit. Indicates that an uncorrectable error
288            occurred during reception of this block.
289            Bit 6: Corrected bit. Indicates that an error was
290            corrected for this data block.
291            Bits 5-3: Received Offset. Indicates the offset received
292            by the sync system.
293            Bits 2-0: Offset Name. Indicates the offset applied to this data.
294
295            SAA6588 byte order is Status-MSB-LSB, so we have to swap the
296            first and the last of the 3 bytes block.
297          */
298
299         tmp = tmpbuf[2];
300         tmpbuf[2] = tmpbuf[0];
301         tmpbuf[0] = tmp;
302
303         tmp = blocknum;
304         tmp |= blocknum << 3;   /* Received offset == Offset Name (OK ?) */
305         if ((tmpbuf[2] & 0x03) == 0x03)
306                 tmp |= 0x80;    /* uncorrectable error */
307         else if ((tmpbuf[2] & 0x03) != 0x00)
308                 tmp |= 0x40;    /* corrected error */
309         tmpbuf[2] = tmp;        /* Is this enough ? Should we also check other bits ? */
310
311         spin_lock_irqsave(&s->lock, flags);
312         block_to_buf(s, tmpbuf);
313         spin_unlock_irqrestore(&s->lock, flags);
314         s->data_available_for_read = 1;
315         wake_up_interruptible(&s->read_queue);
316 }
317
318 static void saa6588_timer(unsigned long data)
319 {
320         struct saa6588 *s = (struct saa6588 *)data;
321
322         schedule_work(&s->work);
323 }
324
325 static void saa6588_work(void *data)
326 {
327         struct saa6588 *s = (struct saa6588 *)data;
328
329         saa6588_i2c_poll(s);
330         mod_timer(&s->timer, jiffies + msecs_to_jiffies(20));
331 }
332
333 static int saa6588_configure(struct saa6588 *s)
334 {
335         unsigned char buf[3];
336         int rc;
337
338         buf[0] = cSyncRestart;
339         if (rbds)
340                 buf[0] |= cProcessingModeRBDS;
341
342         buf[1] = cFlywheelDefault;
343         switch (plvl) {
344         case 0:
345                 buf[1] |= cPauseLevel_11mV;
346                 break;
347         case 1:
348                 buf[1] |= cPauseLevel_17mV;
349                 break;
350         case 2:
351                 buf[1] |= cPauseLevel_27mV;
352                 break;
353         case 3:
354                 buf[1] |= cPauseLevel_43mV;
355                 break;
356         default:                /* nothing */
357                 break;
358         }
359
360         buf[2] = cQualityDetectDefault | cSelectOscFreqON;
361
362         switch (xtal) {
363         case 0:
364                 buf[2] |= cOscFreq_4332kHz;
365                 break;
366         case 1:
367                 buf[2] |= cOscFreq_8664kHz;
368                 break;
369         case 2:
370                 buf[2] |= cOscFreq_12996kHz;
371                 break;
372         case 3:
373                 buf[2] |= cOscFreq_17328kHz;
374                 break;
375         default:                /* nothing */
376                 break;
377         }
378
379         dprintk(PREFIX "writing: 0w=0x%02x 1w=0x%02x 2w=0x%02x\n",
380                 buf[0], buf[1], buf[2]);
381
382         if (3 != (rc = i2c_master_send(&s->client, buf, 3)))
383                 printk(PREFIX "i2c i/o error: rc == %d (should be 3)\n", rc);
384
385         return 0;
386 }
387
388 /* ---------------------------------------------------------------------- */
389
390 static int saa6588_attach(struct i2c_adapter *adap, int addr, int kind)
391 {
392         struct saa6588 *s;
393         client_template.adapter = adap;
394         client_template.addr = addr;
395
396         printk(PREFIX "chip found @ 0x%x\n", addr << 1);
397
398         if (NULL == (s = kmalloc(sizeof(*s), GFP_KERNEL)))
399                 return -ENOMEM;
400
401         s->buf_size = bufblocks * 3;
402
403         if (NULL == (s->buffer = kmalloc(s->buf_size, GFP_KERNEL))) {
404                 kfree(s);
405                 return -ENOMEM;
406         }
407         s->client = client_template;
408         s->block_count = 0;
409         s->wr_index = 0;
410         s->rd_index = 0;
411         s->last_blocknum = 0xff;
412         init_waitqueue_head(&s->read_queue);
413         s->data_available_for_read = 0;
414         i2c_set_clientdata(&s->client, s);
415         i2c_attach_client(&s->client);
416
417         saa6588_configure(s);
418
419         /* start polling via eventd */
420         INIT_WORK(&s->work, saa6588_work, s);
421         init_timer(&s->timer);
422         s->timer.function = saa6588_timer;
423         s->timer.data = (unsigned long)s;
424         schedule_work(&s->work);
425         return 0;
426 }
427
428 static int saa6588_probe(struct i2c_adapter *adap)
429 {
430         if (adap->class & I2C_CLASS_TV_ANALOG)
431                 return i2c_probe(adap, &addr_data, saa6588_attach);
432         return 0;
433 }
434
435 static int saa6588_detach(struct i2c_client *client)
436 {
437         struct saa6588 *s = i2c_get_clientdata(client);
438
439         del_timer_sync(&s->timer);
440         flush_scheduled_work();
441
442         i2c_detach_client(client);
443         kfree(s->buffer);
444         kfree(s);
445         return 0;
446 }
447
448 static int saa6588_command(struct i2c_client *client, unsigned int cmd,
449                                                         void *arg)
450 {
451         struct saa6588 *s = i2c_get_clientdata(client);
452         struct rds_command *a = (struct rds_command *)arg;
453
454         switch (cmd) {
455                 /* --- open() for /dev/radio --- */
456         case RDS_CMD_OPEN:
457                 a->result = 0;  /* return error if chip doesn't work ??? */
458                 break;
459                 /* --- close() for /dev/radio --- */
460         case RDS_CMD_CLOSE:
461                 s->data_available_for_read = 1;
462                 wake_up_interruptible(&s->read_queue);
463                 a->result = 0;
464                 break;
465                 /* --- read() for /dev/radio --- */
466         case RDS_CMD_READ:
467                 read_from_buf(s, a);
468                 break;
469                 /* --- poll() for /dev/radio --- */
470         case RDS_CMD_POLL:
471                 a->result = 0;
472                 if (s->data_available_for_read) {
473                         a->result |= POLLIN | POLLRDNORM;
474                 }
475                 poll_wait(a->instance, &s->read_queue, a->event_list);
476                 break;
477
478         default:
479                 /* nothing */
480                 break;
481         }
482         return 0;
483 }
484
485 /* ----------------------------------------------------------------------- */
486
487 static struct i2c_driver driver = {
488         .driver = {
489                 .name = "saa6588",
490         },
491         .id = -1,               /* FIXME */
492         .attach_adapter = saa6588_probe,
493         .detach_client = saa6588_detach,
494         .command = saa6588_command,
495 };
496
497 static struct i2c_client client_template = {
498         .name = "saa6588",
499         .driver = &driver,
500 };
501
502 static int __init saa6588_init_module(void)
503 {
504         return i2c_add_driver(&driver);
505 }
506
507 static void __exit saa6588_cleanup_module(void)
508 {
509         i2c_del_driver(&driver);
510 }
511
512 module_init(saa6588_init_module);
513 module_exit(saa6588_cleanup_module);
514
515 /*
516  * Overrides for Emacs so that we follow Linus's tabbing style.
517  * ---------------------------------------------------------------------------
518  * Local variables:
519  * c-basic-offset: 8
520  * End:
521  */