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 */ 38static unsigned short normal_i2c[] = { 39 0x20 >> 1, 40 0x22 >> 1, 41 I2C_CLIENT_END, 42}; 43 44I2C_CLIENT_INSMOD; 45 46/* insmod options */ 47static unsigned int debug = 0; 48static unsigned int xtal = 0; 49static unsigned int rbds = 0; 50static unsigned int plvl = 0; 51static unsigned int bufblocks = 100; 52 53module_param(debug, int, 0644); 54MODULE_PARM_DESC(debug, "enable debug messages"); 55module_param(xtal, int, 0); 56MODULE_PARM_DESC(xtal, "select oscillator frequency (0..3), default 0"); 57module_param(rbds, int, 0); 58MODULE_PARM_DESC(rbds, "select mode, 0=RDS, 1=RBDS, default 0"); 59module_param(plvl, int, 0); 60MODULE_PARM_DESC(plvl, "select pause level (0..3), default 0"); 61module_param(bufblocks, int, 0); 62MODULE_PARM_DESC(bufblocks, "number of buffered blocks, default 100"); 63 64MODULE_DESCRIPTION("v4l2 driver module for SAA6588 RDS decoder"); 65MODULE_AUTHOR("Hans J. Koch <koch@hjk-az.de>"); 66 67MODULE_LICENSE("GPL"); 68 69/* ---------------------------------------------------------------------- */ 70 71#define UNSET (-1U) 72#define PREFIX "saa6588: " 73#define dprintk if (debug) printk 74 75struct 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 90static struct i2c_driver driver; 91static 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 159static 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 189static 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 232static 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 260static 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 320static void saa6588_timer(unsigned long data) 321{ 322 struct saa6588 *s = (struct saa6588 *)data; 323 324 schedule_work(&s->work); 325} 326 327static void saa6588_work(struct work_struct *work) 328{ 329 struct saa6588 *s = container_of(work, struct saa6588, work); 330 331 saa6588_i2c_poll(s); 332 mod_timer(&s->timer, jiffies + msecs_to_jiffies(20)); 333} 334 335static 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 392static 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); 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 430static 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 437static 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 450static 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 489static struct i2c_driver driver = { 490 .driver = { 491 .name = "saa6588", 492 }, 493 .id = -1, 494 .attach_adapter = saa6588_probe, 495 .detach_client = saa6588_detach, 496 .command = saa6588_command, 497}; 498 499static struct i2c_client client_template = { 500 .name = "saa6588", 501 .driver = &driver, 502}; 503 504static int __init saa6588_init_module(void) 505{ 506 return i2c_add_driver(&driver); 507} 508 509static void __exit saa6588_cleanup_module(void) 510{ 511 i2c_del_driver(&driver); 512} 513 514module_init(saa6588_init_module); 515module_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 */ 524