Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
[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
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                 spin_unlock_irqrestore(&s->lock, flags);
217                 return;
218         }
219
220         for (i = 0; i < rd_blocks; i++) {
221                 if (block_to_user_buf(s, buf_ptr)) {
222                         buf_ptr += 3;
223                         a->result++;
224                 } else
225                         break;
226         }
227         a->result *= 3;
228         s->data_available_for_read = (s->block_count > 0);
229         spin_unlock_irqrestore(&s->lock, flags);
230 }
231
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
260 static void saa6588_i2c_poll(struct saa6588 *s)
261 {
262         unsigned long flags;
263         unsigned char tmpbuf[6];
264         unsigned char blocknum;
265         unsigned char tmp;
266
267         /* Although we only need 3 bytes, we have to read at least 6.
268            SAA6588 returns garbage otherwise */
269         if (6 != i2c_master_recv(&s->client, &tmpbuf[0], 6)) {
270                 if (debug > 1)
271                         dprintk(PREFIX "read error!\n");
272                 return;
273         }
274
275         blocknum = tmpbuf[0] >> 5;
276         if (blocknum == s->last_blocknum) {
277                 if (debug > 3)
278                         dprintk("Saw block %d again.\n", blocknum);
279                 return;
280         }
281
282         s->last_blocknum = blocknum;
283
284         /*
285            Byte order according to v4l2 specification:
286
287            Byte 0: Least Significant Byte of RDS Block
288            Byte 1: Most Significant Byte of RDS Block
289            Byte 2 Bit 7: Error bit. Indicates that an uncorrectable error
290            occurred during reception of this block.
291            Bit 6: Corrected bit. Indicates that an error was
292            corrected for this data block.
293            Bits 5-3: Received Offset. Indicates the offset received
294            by the sync system.
295            Bits 2-0: Offset Name. Indicates the offset applied to this data.
296
297            SAA6588 byte order is Status-MSB-LSB, so we have to swap the
298            first and the last of the 3 bytes block.
299          */
300
301         tmp = tmpbuf[2];
302         tmpbuf[2] = tmpbuf[0];
303         tmpbuf[0] = tmp;
304
305         tmp = blocknum;
306         tmp |= blocknum << 3;   /* Received offset == Offset Name (OK ?) */
307         if ((tmpbuf[2] & 0x03) == 0x03)
308                 tmp |= 0x80;    /* uncorrectable error */
309         else if ((tmpbuf[2] & 0x03) != 0x00)
310                 tmp |= 0x40;    /* corrected error */
311         tmpbuf[2] = tmp;        /* Is this enough ? Should we also check other bits ? */
312
313         spin_lock_irqsave(&s->lock, flags);
314         block_to_buf(s, tmpbuf);
315         spin_unlock_irqrestore(&s->lock, flags);
316         s->data_available_for_read = 1;
317         wake_up_interruptible(&s->read_queue);
318 }
319
320 static void saa6588_timer(unsigned long data)
321 {
322         struct saa6588 *s = (struct saa6588 *)data;
323
324         schedule_work(&s->work);
325 }
326
327 static void saa6588_work(void *data)
328 {
329         struct saa6588 *s = (struct saa6588 *)data;
330
331         saa6588_i2c_poll(s);
332         mod_timer(&s->timer, jiffies + msecs_to_jiffies(20));
333 }
334
335 static int saa6588_configure(struct saa6588 *s)
336 {
337         unsigned char buf[3];
338         int rc;
339
340         buf[0] = cSyncRestart;
341         if (rbds)
342                 buf[0] |= cProcessingModeRBDS;
343
344         buf[1] = cFlywheelDefault;
345         switch (plvl) {
346         case 0:
347                 buf[1] |= cPauseLevel_11mV;
348                 break;
349         case 1:
350                 buf[1] |= cPauseLevel_17mV;
351                 break;
352         case 2:
353                 buf[1] |= cPauseLevel_27mV;
354                 break;
355         case 3:
356                 buf[1] |= cPauseLevel_43mV;
357                 break;
358         default:                /* nothing */
359                 break;
360         }
361
362         buf[2] = cQualityDetectDefault | cSelectOscFreqON;
363
364         switch (xtal) {
365         case 0:
366                 buf[2] |= cOscFreq_4332kHz;
367                 break;
368         case 1:
369                 buf[2] |= cOscFreq_8664kHz;
370                 break;
371         case 2:
372                 buf[2] |= cOscFreq_12996kHz;
373                 break;
374         case 3:
375                 buf[2] |= cOscFreq_17328kHz;
376                 break;
377         default:                /* nothing */
378                 break;
379         }
380
381         dprintk(PREFIX "writing: 0w=0x%02x 1w=0x%02x 2w=0x%02x\n",
382                 buf[0], buf[1], buf[2]);
383
384         if (3 != (rc = i2c_master_send(&s->client, buf, 3)))
385                 printk(PREFIX "i2c i/o error: rc == %d (should be 3)\n", rc);
386
387         return 0;
388 }
389
390 /* ---------------------------------------------------------------------- */
391
392 static int saa6588_attach(struct i2c_adapter *adap, int addr, int kind)
393 {
394         struct saa6588 *s;
395         client_template.adapter = adap;
396         client_template.addr = addr;
397
398         printk(PREFIX "chip found @ 0x%x\n", addr << 1);
399
400         if (NULL == (s = kmalloc(sizeof(*s), GFP_KERNEL)))
401                 return -ENOMEM;
402
403         s->buf_size = bufblocks * 3;
404
405         if (NULL == (s->buffer = kmalloc(s->buf_size, GFP_KERNEL))) {
406                 kfree(s);
407                 return -ENOMEM;
408         }
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, s);
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  */