Merge branch 'for-linus' of git://www.jni.nu/cris
[linux-2.6] / 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 #include <media/rds.h>
35
36 /* Addresses to scan */
37 static unsigned short normal_i2c[] = {
38         0x20 >> 1,
39         0x22 >> 1,
40         I2C_CLIENT_END,
41 };
42
43 I2C_CLIENT_INSMOD;
44
45 /* insmod options */
46 static unsigned int debug;
47 static unsigned int xtal;
48 static unsigned int rbds;
49 static unsigned int plvl;
50 static unsigned int bufblocks = 100;
51
52 module_param(debug, int, 0644);
53 MODULE_PARM_DESC(debug, "enable debug messages");
54 module_param(xtal, int, 0);
55 MODULE_PARM_DESC(xtal, "select oscillator frequency (0..3), default 0");
56 module_param(rbds, int, 0);
57 MODULE_PARM_DESC(rbds, "select mode, 0=RDS, 1=RBDS, default 0");
58 module_param(plvl, int, 0);
59 MODULE_PARM_DESC(plvl, "select pause level (0..3), default 0");
60 module_param(bufblocks, int, 0);
61 MODULE_PARM_DESC(bufblocks, "number of buffered blocks, default 100");
62
63 MODULE_DESCRIPTION("v4l2 driver module for SAA6588 RDS decoder");
64 MODULE_AUTHOR("Hans J. Koch <koch@hjk-az.de>");
65
66 MODULE_LICENSE("GPL");
67
68 /* ---------------------------------------------------------------------- */
69
70 #define UNSET       (-1U)
71 #define PREFIX      "saa6588: "
72 #define dprintk     if (debug) printk
73
74 struct saa6588 {
75         struct i2c_client client;
76         struct work_struct work;
77         struct timer_list timer;
78         spinlock_t lock;
79         unsigned char *buffer;
80         unsigned int buf_size;
81         unsigned int rd_index;
82         unsigned int wr_index;
83         unsigned int block_count;
84         unsigned char last_blocknum;
85         wait_queue_head_t read_queue;
86         int data_available_for_read;
87 };
88
89 static struct i2c_driver driver;
90 static struct i2c_client client_template;
91
92 /* ---------------------------------------------------------------------- */
93
94 /*
95  * SAA6588 defines
96  */
97
98 /* Initialization and mode control byte (0w) */
99
100 /* bit 0+1 (DAC0/DAC1) */
101 #define cModeStandard           0x00
102 #define cModeFastPI             0x01
103 #define cModeReducedRequest     0x02
104 #define cModeInvalid            0x03
105
106 /* bit 2 (RBDS) */
107 #define cProcessingModeRDS      0x00
108 #define cProcessingModeRBDS     0x04
109
110 /* bit 3+4 (SYM0/SYM1) */
111 #define cErrCorrectionNone      0x00
112 #define cErrCorrection2Bits     0x08
113 #define cErrCorrection5Bits     0x10
114 #define cErrCorrectionNoneRBDS  0x18
115
116 /* bit 5 (NWSY) */
117 #define cSyncNormal             0x00
118 #define cSyncRestart            0x20
119
120 /* bit 6 (TSQD) */
121 #define cSigQualityDetectOFF    0x00
122 #define cSigQualityDetectON     0x40
123
124 /* bit 7 (SQCM) */
125 #define cSigQualityTriggered    0x00
126 #define cSigQualityContinous    0x80
127
128 /* Pause level and flywheel control byte (1w) */
129
130 /* bits 0..5 (FEB0..FEB5) */
131 #define cFlywheelMaxBlocksMask  0x3F
132 #define cFlywheelDefault        0x20
133
134 /* bits 6+7 (PL0/PL1) */
135 #define cPauseLevel_11mV        0x00
136 #define cPauseLevel_17mV        0x40
137 #define cPauseLevel_27mV        0x80
138 #define cPauseLevel_43mV        0xC0
139
140 /* Pause time/oscillator frequency/quality detector control byte (1w) */
141
142 /* bits 0..4 (SQS0..SQS4) */
143 #define cQualityDetectSensMask  0x1F
144 #define cQualityDetectDefault   0x0F
145
146 /* bit 5 (SOSC) */
147 #define cSelectOscFreqOFF       0x00
148 #define cSelectOscFreqON        0x20
149
150 /* bit 6+7 (PTF0/PTF1) */
151 #define cOscFreq_4332kHz        0x00
152 #define cOscFreq_8664kHz        0x40
153 #define cOscFreq_12996kHz       0x80
154 #define cOscFreq_17328kHz       0xC0
155
156 /* ---------------------------------------------------------------------- */
157
158 static int block_to_user_buf(struct saa6588 *s, unsigned char __user *user_buf)
159 {
160         int i;
161
162         if (s->rd_index == s->wr_index) {
163                 if (debug > 2)
164                         dprintk(PREFIX "Read: buffer empty.\n");
165                 return 0;
166         }
167
168         if (debug > 2) {
169                 dprintk(PREFIX "Read: ");
170                 for (i = s->rd_index; i < s->rd_index + 3; i++)
171                         dprintk("0x%02x ", s->buffer[i]);
172         }
173
174         if (copy_to_user(user_buf, &s->buffer[s->rd_index], 3))
175                 return -EFAULT;
176
177         s->rd_index += 3;
178         if (s->rd_index >= s->buf_size)
179                 s->rd_index = 0;
180         s->block_count--;
181
182         if (debug > 2)
183                 dprintk("%d blocks total.\n", s->block_count);
184
185         return 1;
186 }
187
188 static void read_from_buf(struct saa6588 *s, struct rds_command *a)
189 {
190         unsigned long flags;
191
192         unsigned char __user *buf_ptr = a->buffer;
193         unsigned int i;
194         unsigned int rd_blocks;
195
196         a->result = 0;
197         if (!a->buffer)
198                 return;
199
200         while (!s->data_available_for_read) {
201                 int ret = wait_event_interruptible(s->read_queue,
202                                              s->data_available_for_read);
203                 if (ret == -ERESTARTSYS) {
204                         a->result = -EINTR;
205                         return;
206                 }
207         }
208
209         spin_lock_irqsave(&s->lock, flags);
210         rd_blocks = a->block_count;
211         if (rd_blocks > s->block_count)
212                 rd_blocks = s->block_count;
213
214         if (!rd_blocks) {
215                 spin_unlock_irqrestore(&s->lock, flags);
216                 return;
217         }
218
219         for (i = 0; i < rd_blocks; i++) {
220                 if (block_to_user_buf(s, buf_ptr)) {
221                         buf_ptr += 3;
222                         a->result++;
223                 } else
224                         break;
225         }
226         a->result *= 3;
227         s->data_available_for_read = (s->block_count > 0);
228         spin_unlock_irqrestore(&s->lock, flags);
229 }
230
231 static void block_to_buf(struct saa6588 *s, unsigned char *blockbuf)
232 {
233         unsigned int i;
234
235         if (debug > 3)
236                 dprintk(PREFIX "New block: ");
237
238         for (i = 0; i < 3; ++i) {
239                 if (debug > 3)
240                         dprintk("0x%02x ", blockbuf[i]);
241                 s->buffer[s->wr_index] = blockbuf[i];
242                 s->wr_index++;
243         }
244
245         if (s->wr_index >= s->buf_size)
246                 s->wr_index = 0;
247
248         if (s->wr_index == s->rd_index) {
249                 s->rd_index += 3;
250                 if (s->rd_index >= s->buf_size)
251                         s->rd_index = 0;
252         } else
253                 s->block_count++;
254
255         if (debug > 3)
256                 dprintk("%d blocks total.\n", s->block_count);
257 }
258
259 static void saa6588_i2c_poll(struct saa6588 *s)
260 {
261         unsigned long flags;
262         unsigned char tmpbuf[6];
263         unsigned char blocknum;
264         unsigned char tmp;
265
266         /* Although we only need 3 bytes, we have to read at least 6.
267            SAA6588 returns garbage otherwise */
268         if (6 != i2c_master_recv(&s->client, &tmpbuf[0], 6)) {
269                 if (debug > 1)
270                         dprintk(PREFIX "read error!\n");
271                 return;
272         }
273
274         blocknum = tmpbuf[0] >> 5;
275         if (blocknum == s->last_blocknum) {
276                 if (debug > 3)
277                         dprintk("Saw block %d again.\n", blocknum);
278                 return;
279         }
280
281         s->last_blocknum = blocknum;
282
283         /*
284            Byte order according to v4l2 specification:
285
286            Byte 0: Least Significant Byte of RDS Block
287            Byte 1: Most Significant Byte of RDS Block
288            Byte 2 Bit 7: Error bit. Indicates that an uncorrectable error
289            occurred during reception of this block.
290            Bit 6: Corrected bit. Indicates that an error was
291            corrected for this data block.
292            Bits 5-3: Received Offset. Indicates the offset received
293            by the sync system.
294            Bits 2-0: Offset Name. Indicates the offset applied to this data.
295
296            SAA6588 byte order is Status-MSB-LSB, so we have to swap the
297            first and the last of the 3 bytes block.
298          */
299
300         tmp = tmpbuf[2];
301         tmpbuf[2] = tmpbuf[0];
302         tmpbuf[0] = tmp;
303
304         tmp = blocknum;
305         tmp |= blocknum << 3;   /* Received offset == Offset Name (OK ?) */
306         if ((tmpbuf[2] & 0x03) == 0x03)
307                 tmp |= 0x80;    /* uncorrectable error */
308         else if ((tmpbuf[2] & 0x03) != 0x00)
309                 tmp |= 0x40;    /* corrected error */
310         tmpbuf[2] = tmp;        /* Is this enough ? Should we also check other bits ? */
311
312         spin_lock_irqsave(&s->lock, flags);
313         block_to_buf(s, tmpbuf);
314         spin_unlock_irqrestore(&s->lock, flags);
315         s->data_available_for_read = 1;
316         wake_up_interruptible(&s->read_queue);
317 }
318
319 static void saa6588_timer(unsigned long data)
320 {
321         struct saa6588 *s = (struct saa6588 *)data;
322
323         schedule_work(&s->work);
324 }
325
326 static void saa6588_work(struct work_struct *work)
327 {
328         struct saa6588 *s = container_of(work, struct saa6588, work);
329
330         saa6588_i2c_poll(s);
331         mod_timer(&s->timer, jiffies + msecs_to_jiffies(20));
332 }
333
334 static int saa6588_configure(struct saa6588 *s)
335 {
336         unsigned char buf[3];
337         int rc;
338
339         buf[0] = cSyncRestart;
340         if (rbds)
341                 buf[0] |= cProcessingModeRBDS;
342
343         buf[1] = cFlywheelDefault;
344         switch (plvl) {
345         case 0:
346                 buf[1] |= cPauseLevel_11mV;
347                 break;
348         case 1:
349                 buf[1] |= cPauseLevel_17mV;
350                 break;
351         case 2:
352                 buf[1] |= cPauseLevel_27mV;
353                 break;
354         case 3:
355                 buf[1] |= cPauseLevel_43mV;
356                 break;
357         default:                /* nothing */
358                 break;
359         }
360
361         buf[2] = cQualityDetectDefault | cSelectOscFreqON;
362
363         switch (xtal) {
364         case 0:
365                 buf[2] |= cOscFreq_4332kHz;
366                 break;
367         case 1:
368                 buf[2] |= cOscFreq_8664kHz;
369                 break;
370         case 2:
371                 buf[2] |= cOscFreq_12996kHz;
372                 break;
373         case 3:
374                 buf[2] |= cOscFreq_17328kHz;
375                 break;
376         default:                /* nothing */
377                 break;
378         }
379
380         dprintk(PREFIX "writing: 0w=0x%02x 1w=0x%02x 2w=0x%02x\n",
381                 buf[0], buf[1], buf[2]);
382
383         if (3 != (rc = i2c_master_send(&s->client, buf, 3)))
384                 printk(PREFIX "i2c i/o error: rc == %d (should be 3)\n", rc);
385
386         return 0;
387 }
388
389 /* ---------------------------------------------------------------------- */
390
391 static int saa6588_attach(struct i2c_adapter *adap, int addr, int kind)
392 {
393         struct saa6588 *s;
394         client_template.adapter = adap;
395         client_template.addr = addr;
396
397         printk(PREFIX "chip found @ 0x%x\n", addr << 1);
398
399         if (NULL == (s = kmalloc(sizeof(*s), GFP_KERNEL)))
400                 return -ENOMEM;
401
402         s->buf_size = bufblocks * 3;
403
404         if (NULL == (s->buffer = kmalloc(s->buf_size, GFP_KERNEL))) {
405                 kfree(s);
406                 return -ENOMEM;
407         }
408         spin_lock_init(&s->lock);
409         s->client = client_template;
410         s->block_count = 0;
411         s->wr_index = 0;
412         s->rd_index = 0;
413         s->last_blocknum = 0xff;
414         init_waitqueue_head(&s->read_queue);
415         s->data_available_for_read = 0;
416         i2c_set_clientdata(&s->client, s);
417         i2c_attach_client(&s->client);
418
419         saa6588_configure(s);
420
421         /* start polling via eventd */
422         INIT_WORK(&s->work, saa6588_work);
423         init_timer(&s->timer);
424         s->timer.function = saa6588_timer;
425         s->timer.data = (unsigned long)s;
426         schedule_work(&s->work);
427         return 0;
428 }
429
430 static int saa6588_probe(struct i2c_adapter *adap)
431 {
432         if (adap->class & I2C_CLASS_TV_ANALOG)
433                 return i2c_probe(adap, &addr_data, saa6588_attach);
434         return 0;
435 }
436
437 static int saa6588_detach(struct i2c_client *client)
438 {
439         struct saa6588 *s = i2c_get_clientdata(client);
440
441         del_timer_sync(&s->timer);
442         flush_scheduled_work();
443
444         i2c_detach_client(client);
445         kfree(s->buffer);
446         kfree(s);
447         return 0;
448 }
449
450 static int saa6588_command(struct i2c_client *client, unsigned int cmd,
451                                                         void *arg)
452 {
453         struct saa6588 *s = i2c_get_clientdata(client);
454         struct rds_command *a = (struct rds_command *)arg;
455
456         switch (cmd) {
457                 /* --- open() for /dev/radio --- */
458         case RDS_CMD_OPEN:
459                 a->result = 0;  /* return error if chip doesn't work ??? */
460                 break;
461                 /* --- close() for /dev/radio --- */
462         case RDS_CMD_CLOSE:
463                 s->data_available_for_read = 1;
464                 wake_up_interruptible(&s->read_queue);
465                 a->result = 0;
466                 break;
467                 /* --- read() for /dev/radio --- */
468         case RDS_CMD_READ:
469                 read_from_buf(s, a);
470                 break;
471                 /* --- poll() for /dev/radio --- */
472         case RDS_CMD_POLL:
473                 a->result = 0;
474                 if (s->data_available_for_read) {
475                         a->result |= POLLIN | POLLRDNORM;
476                 }
477                 poll_wait(a->instance, &s->read_queue, a->event_list);
478                 break;
479
480         default:
481                 /* nothing */
482                 break;
483         }
484         return 0;
485 }
486
487 /* ----------------------------------------------------------------------- */
488
489 static struct i2c_driver driver = {
490         .driver = {
491                 .name = "saa6588",
492         },
493         .id = -1,               /* FIXME */
494         .attach_adapter = saa6588_probe,
495         .detach_client = saa6588_detach,
496         .command = saa6588_command,
497 };
498
499 static struct i2c_client client_template = {
500         .name = "saa6588",
501         .driver = &driver,
502 };
503
504 static int __init saa6588_init_module(void)
505 {
506         return i2c_add_driver(&driver);
507 }
508
509 static void __exit saa6588_cleanup_module(void)
510 {
511         i2c_del_driver(&driver);
512 }
513
514 module_init(saa6588_init_module);
515 module_exit(saa6588_cleanup_module);
516
517 /*
518  * Overrides for Emacs so that we follow Linus's tabbing style.
519  * ---------------------------------------------------------------------------
520  * Local variables:
521  * c-basic-offset: 8
522  * End:
523  */