drivers/rtc/rtc-rx8025.c

   1 /*
   2  * Driver for Epson's RTC module RX-8025 SA/NB
   3  *
   4  * Copyright (C) 2009 Wolfgang Grandegger <wg@grandegger.com>
   5  *
   6  * Copyright (C) 2005 by Digi International Inc.
   7  * All rights reserved.
   8  *
   9  * Modified by fengjh at rising.com.cn
  10  * <http://lists.lm-sensors.org/mailman/listinfo/lm-sensors>
  11  * 2006.11
  12  *
  13  * Code cleanup by Sergei Poselenov, <sposelenov@emcraft.com>
  14  * Converted to new style by Wolfgang Grandegger <wg@grandegger.com>
  15  * Alarm and periodic interrupt added by Dmitry Rakhchev <rda@emcraft.com>
  16  *
  17  * This program is free software; you can redistribute it and/or
  18  * modify it under the terms of the GNU General Public License
  19  * version 2 as published by the Free Software Foundation.
  20  */
  21 #include <linux/bcd.h>
  22 #include <linux/bitops.h>
  23 #include <linux/i2c.h>
  24 #include <linux/kernel.h>
  25 #include <linux/module.h>
  26 #include <linux/rtc.h>
  27
  28 /* Register definitions */
  29 #define RX8025_REG_SEC          0x00
  30 #define RX8025_REG_MIN          0x01
  31 #define RX8025_REG_HOUR         0x02
  32 #define RX8025_REG_WDAY         0x03
  33 #define RX8025_REG_MDAY         0x04
  34 #define RX8025_REG_MONTH        0x05
  35 #define RX8025_REG_YEAR         0x06
  36 #define RX8025_REG_DIGOFF       0x07
  37 #define RX8025_REG_ALWMIN       0x08
  38 #define RX8025_REG_ALWHOUR      0x09
  39 #define RX8025_REG_ALWWDAY      0x0a
  40 #define RX8025_REG_ALDMIN       0x0b
  41 #define RX8025_REG_ALDHOUR      0x0c
  42 /* 0x0d is reserved */
  43 #define RX8025_REG_CTRL1        0x0e
  44 #define RX8025_REG_CTRL2        0x0f
  45
  46 #define RX8025_BIT_CTRL1_CT     (7 << 0)
  47 /* 1 Hz periodic level irq */
  48 #define RX8025_BIT_CTRL1_CT_1HZ 4
  49 #define RX8025_BIT_CTRL1_TEST   BIT(3)
  50 #define RX8025_BIT_CTRL1_1224   BIT(5)
  51 #define RX8025_BIT_CTRL1_DALE   BIT(6)
  52 #define RX8025_BIT_CTRL1_WALE   BIT(7)
  53
  54 #define RX8025_BIT_CTRL2_DAFG   BIT(0)
  55 #define RX8025_BIT_CTRL2_WAFG   BIT(1)
  56 #define RX8025_BIT_CTRL2_CTFG   BIT(2)
  57 #define RX8025_BIT_CTRL2_PON    BIT(4)
  58 #define RX8025_BIT_CTRL2_XST    BIT(5)
  59 #define RX8025_BIT_CTRL2_VDET   BIT(6)
  60
  61 /* Clock precision adjustment */
  62 #define RX8025_ADJ_RESOLUTION   3050 /* in ppb */
  63 #define RX8025_ADJ_DATA_MAX     62
  64 #define RX8025_ADJ_DATA_MIN     -62
  65
  66 static const struct i2c_device_id rx8025_id[] = {
  67         { "rx8025", 0 },
  68         { }
  69 };
  70 MODULE_DEVICE_TABLE(i2c, rx8025_id);
  71
  72 struct rx8025_data {
  73         struct i2c_client *client;
  74         struct rtc_device *rtc;
  75         u8 ctrl1;
  76 };
  77
  78 static int rx8025_read_reg(struct i2c_client *client, int number, u8 *value)
  79 {
  80         int ret = i2c_smbus_read_byte_data(client, (number << 4) | 0x08);
  81
  82         if (ret < 0) {
  83                 dev_err(&client->dev, "Unable to read register #%d\n", number);
  84                 return ret;
  85         }
  86
  87         *value = ret;
  88         return 0;
  89 }
  90
  91 static int rx8025_read_regs(struct i2c_client *client,
  92                             int number, u8 length, u8 *values)
  93 {
  94         int ret = i2c_smbus_read_i2c_block_data(client, (number << 4) | 0x08,
  95                                                 length, values);
  96
  97         if (ret != length) {
  98                 dev_err(&client->dev, "Unable to read registers #%d..#%d\n",
  99                         number, number + length - 1);
 100                 return ret < 0 ? ret : -EIO;
 101         }
 102
 103         return 0;
 104 }
 105
 106 static int rx8025_write_reg(struct i2c_client *client, int number, u8 value)
 107 {
 108         int ret = i2c_smbus_write_byte_data(client, number << 4, value);
 109
 110         if (ret)
 111                 dev_err(&client->dev, "Unable to write register #%d\n",
 112                         number);
 113
 114         return ret;
 115 }
 116
 117 static int rx8025_write_regs(struct i2c_client *client,
 118                              int number, u8 length, u8 *values)
 119 {
 120         int ret = i2c_smbus_write_i2c_block_data(client, (number << 4) | 0x08,
 121                                                  length, values);
 122
 123         if (ret)
 124                 dev_err(&client->dev, "Unable to write registers #%d..#%d\n",
 125                         number, number + length - 1);
 126
 127         return ret;
 128 }
 129
 130 static irqreturn_t rx8025_handle_irq(int irq, void *dev_id)
 131 {
 132         struct i2c_client *client = dev_id;
 133         struct rx8025_data *rx8025 = i2c_get_clientdata(client);
 134         u8 status;
 135
 136         if (rx8025_read_reg(client, RX8025_REG_CTRL2, &status))
 137                 goto out;
 138
 139         if (!(status & RX8025_BIT_CTRL2_XST))
 140                 dev_warn(&client->dev, "Oscillation stop was detected,"
 141                          "you may have to readjust the clock\n");
 142
 143         if (status & RX8025_BIT_CTRL2_CTFG) {
 144                 /* periodic */
 145                 status &= ~RX8025_BIT_CTRL2_CTFG;
 146                 rtc_update_irq(rx8025->rtc, 1, RTC_PF | RTC_IRQF);
 147         }
 148
 149         if (status & RX8025_BIT_CTRL2_DAFG) {
 150                 /* alarm */
 151                 status &= RX8025_BIT_CTRL2_DAFG;
 152                 if (rx8025_write_reg(client, RX8025_REG_CTRL1,
 153                                      rx8025->ctrl1 & ~RX8025_BIT_CTRL1_DALE))
 154                         goto out;
 155                 rtc_update_irq(rx8025->rtc, 1, RTC_AF | RTC_IRQF);
 156         }
 157
 158         /* acknowledge IRQ */
 159         rx8025_write_reg(client, RX8025_REG_CTRL2,
 160                          status | RX8025_BIT_CTRL2_XST);
 161
 162 out:
 163         return IRQ_HANDLED;
 164 }
 165
 166 static int rx8025_get_time(struct device *dev, struct rtc_time *dt)
 167 {
 168         struct rx8025_data *rx8025 = dev_get_drvdata(dev);
 169         u8 date[7];
 170         int err;
 171
 172         err = rx8025_read_regs(rx8025->client, RX8025_REG_SEC, 7, date);
 173         if (err)
 174                 return err;
 175
 176         dev_dbg(dev, "%s: read 0x%02x 0x%02x "
 177                 "0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n", __func__,
 178                 date[0], date[1], date[2], date[3], date[4],
 179                 date[5], date[6]);
 180
 181         dt->tm_sec = bcd2bin(date[RX8025_REG_SEC] & 0x7f);
 182         dt->tm_min = bcd2bin(date[RX8025_REG_MIN] & 0x7f);
 183         if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
 184                 dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x3f);
 185         else
 186                 dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x1f) % 12
 187                         + (date[RX8025_REG_HOUR] & 0x20 ? 12 : 0);
 188
 189         dt->tm_mday = bcd2bin(date[RX8025_REG_MDAY] & 0x3f);
 190         dt->tm_mon = bcd2bin(date[RX8025_REG_MONTH] & 0x1f) - 1;
 191         dt->tm_year = bcd2bin(date[RX8025_REG_YEAR]);
 192
 193         if (dt->tm_year < 70)
 194                 dt->tm_year += 100;
 195
 196         dev_dbg(dev, "%s: date %ds %dm %dh %dmd %dm %dy\n", __func__,
 197                 dt->tm_sec, dt->tm_min, dt->tm_hour,
 198                 dt->tm_mday, dt->tm_mon, dt->tm_year);
 199
 200         return rtc_valid_tm(dt);
 201 }
 202
 203 static int rx8025_set_time(struct device *dev, struct rtc_time *dt)
 204 {
 205         struct rx8025_data *rx8025 = dev_get_drvdata(dev);
 206         u8 date[7];
 207
 208         /*
 209          * BUG: The HW assumes every year that is a multiple of 4 to be a leap
 210          * year.  Next time this is wrong is 2100, which will not be a leap
 211          * year.
 212          */
 213
 214         /*
 215          * Here the read-only bits are written as "0".  I'm not sure if that
 216          * is sound.
 217          */
 218         date[RX8025_REG_SEC] = bin2bcd(dt->tm_sec);
 219         date[RX8025_REG_MIN] = bin2bcd(dt->tm_min);
 220         if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
 221                 date[RX8025_REG_HOUR] = bin2bcd(dt->tm_hour);
 222         else
 223                 date[RX8025_REG_HOUR] = (dt->tm_hour >= 12 ? 0x20 : 0)
 224                         | bin2bcd((dt->tm_hour + 11) % 12 + 1);
 225
 226         date[RX8025_REG_WDAY] = bin2bcd(dt->tm_wday);
 227         date[RX8025_REG_MDAY] = bin2bcd(dt->tm_mday);
 228         date[RX8025_REG_MONTH] = bin2bcd(dt->tm_mon + 1);
 229         date[RX8025_REG_YEAR] = bin2bcd(dt->tm_year % 100);
 230
 231         dev_dbg(dev,
 232                 "%s: write 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n",
 233                 __func__,
 234                 date[0], date[1], date[2], date[3], date[4], date[5], date[6]);
 235
 236         return rx8025_write_regs(rx8025->client, RX8025_REG_SEC, 7, date);
 237 }
 238
 239 static int rx8025_init_client(struct i2c_client *client, int *need_reset)
 240 {
 241         struct rx8025_data *rx8025 = i2c_get_clientdata(client);
 242         u8 ctrl[2], ctrl2;
 243         int need_clear = 0;
 244         int err;
 245
 246         err = rx8025_read_regs(rx8025->client, RX8025_REG_CTRL1, 2, ctrl);
 247         if (err)
 248                 goto out;
 249
 250         /* Keep test bit zero ! */
 251         rx8025->ctrl1 = ctrl[0] & ~RX8025_BIT_CTRL1_TEST;
 252
 253         if (ctrl[1] & RX8025_BIT_CTRL2_PON) {
 254                 dev_warn(&client->dev, "power-on reset was detected, "
 255                          "you may have to readjust the clock\n");
 256                 *need_reset = 1;
 257         }
 258
 259         if (ctrl[1] & RX8025_BIT_CTRL2_VDET) {
 260                 dev_warn(&client->dev, "a power voltage drop was detected, "
 261                          "you may have to readjust the clock\n");
 262                 *need_reset = 1;
 263         }
 264
 265         if (!(ctrl[1] & RX8025_BIT_CTRL2_XST)) {
 266                 dev_warn(&client->dev, "Oscillation stop was detected,"
 267                          "you may have to readjust the clock\n");
 268                 *need_reset = 1;
 269         }
 270
 271         if (ctrl[1] & (RX8025_BIT_CTRL2_DAFG | RX8025_BIT_CTRL2_WAFG)) {
 272                 dev_warn(&client->dev, "Alarm was detected\n");
 273                 need_clear = 1;
 274         }
 275
 276         if (!(ctrl[1] & RX8025_BIT_CTRL2_CTFG))
 277                 need_clear = 1;
 278
 279         if (*need_reset || need_clear) {
 280                 ctrl2 = ctrl[0];
 281                 ctrl2 &= ~(RX8025_BIT_CTRL2_PON | RX8025_BIT_CTRL2_VDET |
 282                            RX8025_BIT_CTRL2_CTFG | RX8025_BIT_CTRL2_WAFG |
 283                            RX8025_BIT_CTRL2_DAFG);
 284                 ctrl2 |= RX8025_BIT_CTRL2_XST;
 285
 286                 err = rx8025_write_reg(client, RX8025_REG_CTRL2, ctrl2);
 287         }
 288 out:
 289         return err;
 290 }
 291
 292 /* Alarm support */
 293 static int rx8025_read_alarm(struct device *dev, struct rtc_wkalrm *t)
 294 {
 295         struct rx8025_data *rx8025 = dev_get_drvdata(dev);
 296         struct i2c_client *client = rx8025->client;
 297         u8 ctrl2, ald[2];
 298         int err;
 299
 300         if (client->irq <= 0)
 301                 return -EINVAL;
 302
 303         err = rx8025_read_regs(client, RX8025_REG_ALDMIN, 2, ald);
 304         if (err)
 305                 return err;
 306
 307         err = rx8025_read_reg(client, RX8025_REG_CTRL2, &ctrl2);
 308         if (err)
 309                 return err;
 310
 311         dev_dbg(dev, "%s: read alarm 0x%02x 0x%02x ctrl2 %02x\n",
 312                 __func__, ald[0], ald[1], ctrl2);
 313
 314         /* Hardware alarms precision is 1 minute! */
 315         t->time.tm_sec = 0;
 316         t->time.tm_min = bcd2bin(ald[0] & 0x7f);
 317         if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
 318                 t->time.tm_hour = bcd2bin(ald[1] & 0x3f);
 319         else
 320                 t->time.tm_hour = bcd2bin(ald[1] & 0x1f) % 12
 321                         + (ald[1] & 0x20 ? 12 : 0);
 322
 323         t->time.tm_wday = -1;
 324         t->time.tm_mday = -1;
 325         t->time.tm_mon = -1;
 326         t->time.tm_year = -1;
 327
 328         dev_dbg(dev, "%s: date: %ds %dm %dh %dmd %dm %dy\n",
 329                 __func__,
 330                 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
 331                 t->time.tm_mday, t->time.tm_mon, t->time.tm_year);
 332         t->enabled = !!(rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE);
 333         t->pending = (ctrl2 & RX8025_BIT_CTRL2_DAFG) && t->enabled;
 334
 335         return err;
 336 }
 337
 338 static int rx8025_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 339 {
 340         struct i2c_client *client = to_i2c_client(dev);
 341         struct rx8025_data *rx8025 = dev_get_drvdata(dev);
 342         u8 ald[2];
 343         int err;
 344
 345         if (client->irq <= 0)
 346                 return -EINVAL;
 347
 348         /* Hardware alarm precision is 1 minute! */
 349         ald[0] = bin2bcd(t->time.tm_min);
 350         if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
 351                 ald[1] = bin2bcd(t->time.tm_hour);
 352         else
 353                 ald[1] = (t->time.tm_hour >= 12 ? 0x20 : 0)
 354                         | bin2bcd((t->time.tm_hour + 11) % 12 + 1);
 355
 356         dev_dbg(dev, "%s: write 0x%02x 0x%02x\n", __func__, ald[0], ald[1]);
 357
 358         if (rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE) {
 359                 rx8025->ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
 360                 err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
 361                                        rx8025->ctrl1);
 362                 if (err)
 363                         return err;
 364         }
 365         err = rx8025_write_regs(rx8025->client, RX8025_REG_ALDMIN, 2, ald);
 366         if (err)
 367                 return err;
 368
 369         if (t->enabled) {
 370                 rx8025->ctrl1 |= RX8025_BIT_CTRL1_DALE;
 371                 err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
 372                                        rx8025->ctrl1);
 373                 if (err)
 374                         return err;
 375         }
 376
 377         return 0;
 378 }
 379
 380 static int rx8025_alarm_irq_enable(struct device *dev, unsigned int enabled)
 381 {
 382         struct rx8025_data *rx8025 = dev_get_drvdata(dev);
 383         u8 ctrl1;
 384         int err;
 385
 386         ctrl1 = rx8025->ctrl1;
 387         if (enabled)
 388                 ctrl1 |= RX8025_BIT_CTRL1_DALE;
 389         else
 390                 ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
 391
 392         if (ctrl1 != rx8025->ctrl1) {
 393                 rx8025->ctrl1 = ctrl1;
 394                 err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
 395                                        rx8025->ctrl1);
 396                 if (err)
 397                         return err;
 398         }
 399         return 0;
 400 }
 401
 402 static struct rtc_class_ops rx8025_rtc_ops = {
 403         .read_time = rx8025_get_time,
 404         .set_time = rx8025_set_time,
 405         .read_alarm = rx8025_read_alarm,
 406         .set_alarm = rx8025_set_alarm,
 407         .alarm_irq_enable = rx8025_alarm_irq_enable,
 408 };
 409
 410 /*
 411  * Clock precision adjustment support
 412  *
 413  * According to the RX8025 SA/NB application manual the frequency and
 414  * temperature characteristics can be approximated using the following
 415  * equation:
 416  *
 417  *   df = a * (ut - t)**2
 418  *
 419  *   df: Frequency deviation in any temperature
 420  *   a : Coefficient = (-35 +-5) * 10**-9
 421  *   ut: Ultimate temperature in degree = +25 +-5 degree
 422  *   t : Any temperature in degree
 423  *
 424  * Note that the clock adjustment in ppb must be entered (which is
 425  * the negative value of the deviation).
 426  */
 427 static int rx8025_get_clock_adjust(struct device *dev, int *adj)
 428 {
 429         struct i2c_client *client = to_i2c_client(dev);
 430         u8 digoff;
 431         int err;
 432
 433         err = rx8025_read_reg(client, RX8025_REG_DIGOFF, &digoff);
 434         if (err)
 435                 return err;
 436
 437         *adj = digoff >= 64 ? digoff - 128 : digoff;
 438         if (*adj > 0)
 439                 (*adj)--;
 440         *adj *= -RX8025_ADJ_RESOLUTION;
 441
 442         return 0;
 443 }
 444
 445 static int rx8025_set_clock_adjust(struct device *dev, int adj)
 446 {
 447         struct i2c_client *client = to_i2c_client(dev);
 448         u8 digoff;
 449         int err;
 450
 451         adj /= -RX8025_ADJ_RESOLUTION;
 452         if (adj > RX8025_ADJ_DATA_MAX)
 453                 adj = RX8025_ADJ_DATA_MAX;
 454         else if (adj < RX8025_ADJ_DATA_MIN)
 455                 adj = RX8025_ADJ_DATA_MIN;
 456         else if (adj > 0)
 457                 adj++;
 458         else if (adj < 0)
 459                 adj += 128;
 460         digoff = adj;
 461
 462         err = rx8025_write_reg(client, RX8025_REG_DIGOFF, digoff);
 463         if (err)
 464                 return err;
 465
 466         dev_dbg(dev, "%s: write 0x%02x\n", __func__, digoff);
 467
 468         return 0;
 469 }
 470
 471 static ssize_t rx8025_sysfs_show_clock_adjust(struct device *dev,
 472                                               struct device_attribute *attr,
 473                                               char *buf)
 474 {
 475         int err, adj;
 476
 477         err = rx8025_get_clock_adjust(dev, &adj);
 478         if (err)
 479                 return err;
 480
 481         return sprintf(buf, "%d\n", adj);
 482 }
 483
 484 static ssize_t rx8025_sysfs_store_clock_adjust(struct device *dev,
 485                                                struct device_attribute *attr,
 486                                                const char *buf, size_t count)
 487 {
 488         int adj, err;
 489
 490         if (sscanf(buf, "%i", &adj) != 1)
 491                 return -EINVAL;
 492
 493         err = rx8025_set_clock_adjust(dev, adj);
 494
 495         return err ? err : count;
 496 }
 497
 498 static DEVICE_ATTR(clock_adjust_ppb, S_IRUGO | S_IWUSR,
 499                    rx8025_sysfs_show_clock_adjust,
 500                    rx8025_sysfs_store_clock_adjust);
 501
 502 static int rx8025_sysfs_register(struct device *dev)
 503 {
 504         return device_create_file(dev, &dev_attr_clock_adjust_ppb);
 505 }
 506
 507 static void rx8025_sysfs_unregister(struct device *dev)
 508 {
 509         device_remove_file(dev, &dev_attr_clock_adjust_ppb);
 510 }
 511
 512 static int rx8025_probe(struct i2c_client *client,
 513                         const struct i2c_device_id *id)
 514 {
 515         struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
 516         struct rx8025_data *rx8025;
 517         int err = 0, need_reset = 0;
 518
 519         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
 520                                      | I2C_FUNC_SMBUS_I2C_BLOCK)) {
 521                 dev_err(&adapter->dev,
 522                         "doesn't support required functionality\n");
 523                 return -EIO;
 524         }
 525
 526         rx8025 = devm_kzalloc(&client->dev, sizeof(*rx8025), GFP_KERNEL);
 527         if (!rx8025) {
 528                 return -ENOMEM;
 529         }
 530
 531         rx8025->client = client;
 532         i2c_set_clientdata(client, rx8025);
 533
 534         err = rx8025_init_client(client, &need_reset);
 535         if (err)
 536                 return err;
 537
 538         if (need_reset) {
 539                 struct rtc_time tm;
 540                 dev_info(&client->dev,
 541                          "bad conditions detected, resetting date\n");
 542                 rtc_time_to_tm(0, &tm); /* 1970/1/1 */
 543                 rx8025_set_time(&client->dev, &tm);
 544         }
 545
 546         rx8025->rtc = devm_rtc_device_register(&client->dev, client->name,
 547                                           &rx8025_rtc_ops, THIS_MODULE);
 548         if (IS_ERR(rx8025->rtc)) {
 549                 dev_err(&client->dev, "unable to register the class device\n");
 550                 return PTR_ERR(rx8025->rtc);
 551         }
 552
 553         if (client->irq > 0) {
 554                 dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
 555                 err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
 556                                                 rx8025_handle_irq, 0, "rx8025",
 557                                                 client);
 558                 if (err) {
 559                         dev_err(&client->dev, "unable to request IRQ\n");
 560                         return err;
 561                 }
 562         }
 563
 564         rx8025->rtc->irq_freq = 1;
 565         rx8025->rtc->max_user_freq = 1;
 566
 567         err = rx8025_sysfs_register(&client->dev);
 568         return err;
 569 }
 570
 571 static int rx8025_remove(struct i2c_client *client)
 572 {
 573         rx8025_sysfs_unregister(&client->dev);
 574         return 0;
 575 }
 576
 577 static struct i2c_driver rx8025_driver = {
 578         .driver = {
 579                 .name = "rtc-rx8025",
 580         },
 581         .probe          = rx8025_probe,
 582         .remove         = rx8025_remove,
 583         .id_table       = rx8025_id,
 584 };
 585
 586 module_i2c_driver(rx8025_driver);
 587
 588 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
 589 MODULE_DESCRIPTION("RX-8025 SA/NB RTC driver");
 590 MODULE_LICENSE("GPL");