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 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 /* ---------------------------------------------------------------------- */ 152 153 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 } 181 182 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 } 231 232 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 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 } 329 330 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 } 337 338 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 /* ---------------------------------------------------------------------- */ 394 395 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 } 426 427 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 } 436 437 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 /* ---------------------------------------------------------------------- */ 462 463 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 } 498 499 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