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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 Driver for SAA6588 RDS decoder4 5 (c) 2005 Hans J. Koch6 7*/8 9 10#include <linux/module.h>11#include <linux/kernel.h>12#include <linux/i2c.h>13#include <linux/types.h>14#include <linux/videodev2.h>15#include <linux/init.h>16#include <linux/errno.h>17#include <linux/slab.h>18#include <linux/poll.h>19#include <linux/wait.h>20#include <linux/uaccess.h>21 22#include <media/i2c/saa6588.h>23#include <media/v4l2-device.h>24 25 26/* insmod options */27static unsigned int debug;28static unsigned int xtal;29static unsigned int mmbs;30static unsigned int plvl;31static unsigned int bufblocks = 100;32 33module_param(debug, int, 0644);34MODULE_PARM_DESC(debug, "enable debug messages");35module_param(xtal, int, 0);36MODULE_PARM_DESC(xtal, "select oscillator frequency (0..3), default 0");37module_param(mmbs, int, 0);38MODULE_PARM_DESC(mmbs, "enable MMBS mode: 0=off (default), 1=on");39module_param(plvl, int, 0);40MODULE_PARM_DESC(plvl, "select pause level (0..3), default 0");41module_param(bufblocks, int, 0);42MODULE_PARM_DESC(bufblocks, "number of buffered blocks, default 100");43 44MODULE_DESCRIPTION("v4l2 driver module for SAA6588 RDS decoder");45MODULE_AUTHOR("Hans J. Koch <koch@hjk-az.de>");46 47MODULE_LICENSE("GPL");48 49/* ---------------------------------------------------------------------- */50 51#define UNSET (-1U)52#define PREFIX "saa6588: "53#define dprintk if (debug) printk54 55struct saa6588 {56 struct v4l2_subdev sd;57 struct delayed_work work;58 spinlock_t lock;59 unsigned char *buffer;60 unsigned int buf_size;61 unsigned int rd_index;62 unsigned int wr_index;63 unsigned int block_count;64 unsigned char last_blocknum;65 wait_queue_head_t read_queue;66 int data_available_for_read;67 u8 sync;68};69 70static inline struct saa6588 *to_saa6588(struct v4l2_subdev *sd)71{72 return container_of(sd, struct saa6588, sd);73}74 75/* ---------------------------------------------------------------------- */76 77/*78 * SAA6588 defines79 */80 81/* Initialization and mode control byte (0w) */82 83/* bit 0+1 (DAC0/DAC1) */84#define cModeStandard 0x0085#define cModeFastPI 0x0186#define cModeReducedRequest 0x0287#define cModeInvalid 0x0388 89/* bit 2 (RBDS) */90#define cProcessingModeRDS 0x0091#define cProcessingModeRBDS 0x0492 93/* bit 3+4 (SYM0/SYM1) */94#define cErrCorrectionNone 0x0095#define cErrCorrection2Bits 0x0896#define cErrCorrection5Bits 0x1097#define cErrCorrectionNoneRBDS 0x1898 99/* bit 5 (NWSY) */100#define cSyncNormal 0x00101#define cSyncRestart 0x20102 103/* bit 6 (TSQD) */104#define cSigQualityDetectOFF 0x00105#define cSigQualityDetectON 0x40106 107/* bit 7 (SQCM) */108#define cSigQualityTriggered 0x00109#define cSigQualityContinous 0x80110 111/* Pause level and flywheel control byte (1w) */112 113/* bits 0..5 (FEB0..FEB5) */114#define cFlywheelMaxBlocksMask 0x3F115#define cFlywheelDefault 0x20116 117/* bits 6+7 (PL0/PL1) */118#define cPauseLevel_11mV 0x00119#define cPauseLevel_17mV 0x40120#define cPauseLevel_27mV 0x80121#define cPauseLevel_43mV 0xC0122 123/* Pause time/oscillator frequency/quality detector control byte (1w) */124 125/* bits 0..4 (SQS0..SQS4) */126#define cQualityDetectSensMask 0x1F127#define cQualityDetectDefault 0x0F128 129/* bit 5 (SOSC) */130#define cSelectOscFreqOFF 0x00131#define cSelectOscFreqON 0x20132 133/* bit 6+7 (PTF0/PTF1) */134#define cOscFreq_4332kHz 0x00135#define cOscFreq_8664kHz 0x40136#define cOscFreq_12996kHz 0x80137#define cOscFreq_17328kHz 0xC0138 139/* ---------------------------------------------------------------------- */140 141static bool block_from_buf(struct saa6588 *s, unsigned char *buf)142{143 int i;144 145 if (s->rd_index == s->wr_index) {146 if (debug > 2)147 dprintk(PREFIX "Read: buffer empty.\n");148 return false;149 }150 151 if (debug > 2) {152 dprintk(PREFIX "Read: ");153 for (i = s->rd_index; i < s->rd_index + 3; i++)154 dprintk("0x%02x ", s->buffer[i]);155 }156 157 memcpy(buf, &s->buffer[s->rd_index], 3);158 159 s->rd_index += 3;160 if (s->rd_index >= s->buf_size)161 s->rd_index = 0;162 s->block_count--;163 164 if (debug > 2)165 dprintk("%d blocks total.\n", s->block_count);166 167 return true;168}169 170static void read_from_buf(struct saa6588 *s, struct saa6588_command *a)171{172 unsigned char __user *buf_ptr = a->buffer;173 unsigned char buf[3];174 unsigned long flags;175 unsigned int rd_blocks;176 unsigned int i;177 178 a->result = 0;179 if (!a->buffer)180 return;181 182 while (!a->nonblocking && !s->data_available_for_read) {183 int ret = wait_event_interruptible(s->read_queue,184 s->data_available_for_read);185 if (ret == -ERESTARTSYS) {186 a->result = -EINTR;187 return;188 }189 }190 191 rd_blocks = a->block_count;192 spin_lock_irqsave(&s->lock, flags);193 if (rd_blocks > s->block_count)194 rd_blocks = s->block_count;195 spin_unlock_irqrestore(&s->lock, flags);196 197 if (!rd_blocks)198 return;199 200 for (i = 0; i < rd_blocks; i++) {201 bool got_block;202 203 spin_lock_irqsave(&s->lock, flags);204 got_block = block_from_buf(s, buf);205 spin_unlock_irqrestore(&s->lock, flags);206 if (!got_block)207 break;208 if (copy_to_user(buf_ptr, buf, 3)) {209 a->result = -EFAULT;210 return;211 }212 buf_ptr += 3;213 a->result += 3;214 }215 spin_lock_irqsave(&s->lock, flags);216 s->data_available_for_read = (s->block_count > 0);217 spin_unlock_irqrestore(&s->lock, flags);218}219 220static void block_to_buf(struct saa6588 *s, unsigned char *blockbuf)221{222 unsigned int i;223 224 if (debug > 3)225 dprintk(PREFIX "New block: ");226 227 for (i = 0; i < 3; ++i) {228 if (debug > 3)229 dprintk("0x%02x ", blockbuf[i]);230 s->buffer[s->wr_index] = blockbuf[i];231 s->wr_index++;232 }233 234 if (s->wr_index >= s->buf_size)235 s->wr_index = 0;236 237 if (s->wr_index == s->rd_index) {238 s->rd_index += 3;239 if (s->rd_index >= s->buf_size)240 s->rd_index = 0;241 } else242 s->block_count++;243 244 if (debug > 3)245 dprintk("%d blocks total.\n", s->block_count);246}247 248static void saa6588_i2c_poll(struct saa6588 *s)249{250 struct i2c_client *client = v4l2_get_subdevdata(&s->sd);251 unsigned long flags;252 unsigned char tmpbuf[6];253 unsigned char blocknum;254 unsigned char tmp;255 256 /* Although we only need 3 bytes, we have to read at least 6.257 SAA6588 returns garbage otherwise. */258 if (6 != i2c_master_recv(client, &tmpbuf[0], 6)) {259 if (debug > 1)260 dprintk(PREFIX "read error!\n");261 return;262 }263 264 s->sync = tmpbuf[0] & 0x10;265 if (!s->sync)266 return;267 blocknum = tmpbuf[0] >> 5;268 if (blocknum == s->last_blocknum) {269 if (debug > 3)270 dprintk("Saw block %d again.\n", blocknum);271 return;272 }273 274 s->last_blocknum = blocknum;275 276 /*277 Byte order according to v4l2 specification:278 279 Byte 0: Least Significant Byte of RDS Block280 Byte 1: Most Significant Byte of RDS Block281 Byte 2 Bit 7: Error bit. Indicates that an uncorrectable error282 occurred during reception of this block.283 Bit 6: Corrected bit. Indicates that an error was284 corrected for this data block.285 Bits 5-3: Same as bits 0-2.286 Bits 2-0: Block number.287 288 SAA6588 byte order is Status-MSB-LSB, so we have to swap the289 first and the last of the 3 bytes block.290 */291 292 swap(tmpbuf[2], tmpbuf[0]);293 294 /* Map 'Invalid block E' to 'Invalid Block' */295 if (blocknum == 6)296 blocknum = V4L2_RDS_BLOCK_INVALID;297 /* And if are not in mmbs mode, then 'Block E' is also mapped298 to 'Invalid Block'. As far as I can tell MMBS is discontinued,299 and if there is ever a need to support E blocks, then please300 contact the linux-media mailinglist. */301 else if (!mmbs && blocknum == 5)302 blocknum = V4L2_RDS_BLOCK_INVALID;303 tmp = blocknum;304 tmp |= blocknum << 3; /* Received offset == Offset Name (OK ?) */305 if ((tmpbuf[2] & 0x03) == 0x03)306 tmp |= V4L2_RDS_BLOCK_ERROR; /* uncorrectable error */307 else if ((tmpbuf[2] & 0x03) != 0x00)308 tmp |= V4L2_RDS_BLOCK_CORRECTED; /* 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 318static void saa6588_work(struct work_struct *work)319{320 struct saa6588 *s = container_of(work, struct saa6588, work.work);321 322 saa6588_i2c_poll(s);323 schedule_delayed_work(&s->work, msecs_to_jiffies(20));324}325 326static void saa6588_configure(struct saa6588 *s)327{328 struct i2c_client *client = v4l2_get_subdevdata(&s->sd);329 unsigned char buf[3];330 int rc;331 332 buf[0] = cSyncRestart;333 if (mmbs)334 buf[0] |= cProcessingModeRBDS;335 336 buf[1] = cFlywheelDefault;337 switch (plvl) {338 case 0:339 buf[1] |= cPauseLevel_11mV;340 break;341 case 1:342 buf[1] |= cPauseLevel_17mV;343 break;344 case 2:345 buf[1] |= cPauseLevel_27mV;346 break;347 case 3:348 buf[1] |= cPauseLevel_43mV;349 break;350 default: /* nothing */351 break;352 }353 354 buf[2] = cQualityDetectDefault | cSelectOscFreqON;355 356 switch (xtal) {357 case 0:358 buf[2] |= cOscFreq_4332kHz;359 break;360 case 1:361 buf[2] |= cOscFreq_8664kHz;362 break;363 case 2:364 buf[2] |= cOscFreq_12996kHz;365 break;366 case 3:367 buf[2] |= cOscFreq_17328kHz;368 break;369 default: /* nothing */370 break;371 }372 373 dprintk(PREFIX "writing: 0w=0x%02x 1w=0x%02x 2w=0x%02x\n",374 buf[0], buf[1], buf[2]);375 376 rc = i2c_master_send(client, buf, 3);377 if (rc != 3)378 printk(PREFIX "i2c i/o error: rc == %d (should be 3)\n", rc);379}380 381/* ---------------------------------------------------------------------- */382 383static long saa6588_command(struct v4l2_subdev *sd, unsigned int cmd, void *arg)384{385 struct saa6588 *s = to_saa6588(sd);386 struct saa6588_command *a = arg;387 388 switch (cmd) {389 /* --- close() for /dev/radio --- */390 case SAA6588_CMD_CLOSE:391 s->data_available_for_read = 1;392 wake_up_interruptible(&s->read_queue);393 s->data_available_for_read = 0;394 a->result = 0;395 break;396 /* --- read() for /dev/radio --- */397 case SAA6588_CMD_READ:398 read_from_buf(s, a);399 break;400 /* --- poll() for /dev/radio --- */401 case SAA6588_CMD_POLL:402 a->poll_mask = 0;403 if (s->data_available_for_read)404 a->poll_mask |= EPOLLIN | EPOLLRDNORM;405 poll_wait(a->instance, &s->read_queue, a->event_list);406 break;407 408 default:409 /* nothing */410 return -ENOIOCTLCMD;411 }412 return 0;413}414 415static int saa6588_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *vt)416{417 struct saa6588 *s = to_saa6588(sd);418 419 vt->capability |= V4L2_TUNER_CAP_RDS | V4L2_TUNER_CAP_RDS_BLOCK_IO;420 if (s->sync)421 vt->rxsubchans |= V4L2_TUNER_SUB_RDS;422 return 0;423}424 425static int saa6588_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *vt)426{427 struct saa6588 *s = to_saa6588(sd);428 429 saa6588_configure(s);430 return 0;431}432 433/* ----------------------------------------------------------------------- */434 435static const struct v4l2_subdev_core_ops saa6588_core_ops = {436 .command = saa6588_command,437};438 439static const struct v4l2_subdev_tuner_ops saa6588_tuner_ops = {440 .g_tuner = saa6588_g_tuner,441 .s_tuner = saa6588_s_tuner,442};443 444static const struct v4l2_subdev_ops saa6588_ops = {445 .core = &saa6588_core_ops,446 .tuner = &saa6588_tuner_ops,447};448 449/* ---------------------------------------------------------------------- */450 451static int saa6588_probe(struct i2c_client *client)452{453 struct saa6588 *s;454 struct v4l2_subdev *sd;455 456 v4l_info(client, "saa6588 found @ 0x%x (%s)\n",457 client->addr << 1, client->adapter->name);458 459 s = devm_kzalloc(&client->dev, sizeof(*s), GFP_KERNEL);460 if (s == NULL)461 return -ENOMEM;462 463 s->buf_size = bufblocks * 3;464 465 s->buffer = devm_kzalloc(&client->dev, s->buf_size, GFP_KERNEL);466 if (s->buffer == NULL)467 return -ENOMEM;468 sd = &s->sd;469 v4l2_i2c_subdev_init(sd, client, &saa6588_ops);470 spin_lock_init(&s->lock);471 s->block_count = 0;472 s->wr_index = 0;473 s->rd_index = 0;474 s->last_blocknum = 0xff;475 init_waitqueue_head(&s->read_queue);476 s->data_available_for_read = 0;477 478 saa6588_configure(s);479 480 /* start polling via eventd */481 INIT_DELAYED_WORK(&s->work, saa6588_work);482 schedule_delayed_work(&s->work, 0);483 return 0;484}485 486static void saa6588_remove(struct i2c_client *client)487{488 struct v4l2_subdev *sd = i2c_get_clientdata(client);489 struct saa6588 *s = to_saa6588(sd);490 491 v4l2_device_unregister_subdev(sd);492 493 cancel_delayed_work_sync(&s->work);494}495 496/* ----------------------------------------------------------------------- */497 498static const struct i2c_device_id saa6588_id[] = {499 { "saa6588" },500 { }501};502MODULE_DEVICE_TABLE(i2c, saa6588_id);503 504static struct i2c_driver saa6588_driver = {505 .driver = {506 .name = "saa6588",507 },508 .probe = saa6588_probe,509 .remove = saa6588_remove,510 .id_table = saa6588_id,511};512 513module_i2c_driver(saa6588_driver);514