drivers/rtc/rtc-pcf8563.c

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This source file includes following definitions.
pcf8563_read_block_data
pcf8563_write_block_data
pcf8563_set_alarm_mode
pcf8563_get_alarm_mode
pcf8563_irq
pcf8563_rtc_read_time
pcf8563_rtc_set_time
pcf8563_rtc_ioctl
pcf8563_rtc_read_alarm
pcf8563_rtc_set_alarm
pcf8563_irq_enable
pcf8563_clkout_recalc_rate
pcf8563_clkout_round_rate
pcf8563_clkout_set_rate
pcf8563_clkout_control
pcf8563_clkout_prepare
pcf8563_clkout_unprepare
pcf8563_clkout_is_prepared
pcf8563_clkout_register_clk
pcf8563_probe
   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * An I2C driver for the Philips PCF8563 RTC
   4  * Copyright 2005-06 Tower Technologies
   5  *
   6  * Author: Alessandro Zummo <a.zummo@towertech.it>
   7  * Maintainers: http://www.nslu2-linux.org/
   8  *
   9  * based on the other drivers in this same directory.
  10  *
  11  * http://www.semiconductors.philips.com/acrobat/datasheets/PCF8563-04.pdf
  12  */
  13 
  14 #include <linux/clk-provider.h>
  15 #include <linux/i2c.h>
  16 #include <linux/bcd.h>
  17 #include <linux/rtc.h>
  18 #include <linux/slab.h>
  19 #include <linux/module.h>
  20 #include <linux/of.h>
  21 #include <linux/err.h>
  22 
  23 #define PCF8563_REG_ST1         0x00 /* status */
  24 #define PCF8563_REG_ST2         0x01
  25 #define PCF8563_BIT_AIE         (1 << 1)
  26 #define PCF8563_BIT_AF          (1 << 3)
  27 #define PCF8563_BITS_ST2_N      (7 << 5)
  28 
  29 #define PCF8563_REG_SC          0x02 /* datetime */
  30 #define PCF8563_REG_MN          0x03
  31 #define PCF8563_REG_HR          0x04
  32 #define PCF8563_REG_DM          0x05
  33 #define PCF8563_REG_DW          0x06
  34 #define PCF8563_REG_MO          0x07
  35 #define PCF8563_REG_YR          0x08
  36 
  37 #define PCF8563_REG_AMN         0x09 /* alarm */
  38 
  39 #define PCF8563_REG_CLKO                0x0D /* clock out */
  40 #define PCF8563_REG_CLKO_FE             0x80 /* clock out enabled */
  41 #define PCF8563_REG_CLKO_F_MASK         0x03 /* frequenc mask */
  42 #define PCF8563_REG_CLKO_F_32768HZ      0x00
  43 #define PCF8563_REG_CLKO_F_1024HZ       0x01
  44 #define PCF8563_REG_CLKO_F_32HZ         0x02
  45 #define PCF8563_REG_CLKO_F_1HZ          0x03
  46 
  47 #define PCF8563_REG_TMRC        0x0E /* timer control */
  48 #define PCF8563_TMRC_ENABLE     BIT(7)
  49 #define PCF8563_TMRC_4096       0
  50 #define PCF8563_TMRC_64         1
  51 #define PCF8563_TMRC_1          2
  52 #define PCF8563_TMRC_1_60       3
  53 #define PCF8563_TMRC_MASK       3
  54 
  55 #define PCF8563_REG_TMR         0x0F /* timer */
  56 
  57 #define PCF8563_SC_LV           0x80 /* low voltage */
  58 #define PCF8563_MO_C            0x80 /* century */
  59 
  60 static struct i2c_driver pcf8563_driver;
  61 
  62 struct pcf8563 {
  63         struct rtc_device *rtc;
  64         /*
  65          * The meaning of MO_C bit varies by the chip type.
  66          * From PCF8563 datasheet: this bit is toggled when the years
  67          * register overflows from 99 to 00
  68          *   0 indicates the century is 20xx
  69          *   1 indicates the century is 19xx
  70          * From RTC8564 datasheet: this bit indicates change of
  71          * century. When the year digit data overflows from 99 to 00,
  72          * this bit is set. By presetting it to 0 while still in the
  73          * 20th century, it will be set in year 2000, ...
  74          * There seems no reliable way to know how the system use this
  75          * bit.  So let's do it heuristically, assuming we are live in
  76          * 1970...2069.
  77          */
  78         int c_polarity; /* 0: MO_C=1 means 19xx, otherwise MO_C=1 means 20xx */
  79         int voltage_low; /* incicates if a low_voltage was detected */
  80 
  81         struct i2c_client *client;
  82 #ifdef CONFIG_COMMON_CLK
  83         struct clk_hw           clkout_hw;
  84 #endif
  85 };
  86 
  87 static int pcf8563_read_block_data(struct i2c_client *client, unsigned char reg,
  88                                    unsigned char length, unsigned char *buf)
  89 {
  90         struct i2c_msg msgs[] = {
  91                 {/* setup read ptr */
  92                         .addr = client->addr,
  93                         .len = 1,
  94                         .buf = &reg,
  95                 },
  96                 {
  97                         .addr = client->addr,
  98                         .flags = I2C_M_RD,
  99                         .len = length,
 100                         .buf = buf
 101                 },
 102         };
 103 
 104         if ((i2c_transfer(client->adapter, msgs, 2)) != 2) {
 105                 dev_err(&client->dev, "%s: read error\n", __func__);
 106                 return -EIO;
 107         }
 108 
 109         return 0;
 110 }
 111 
 112 static int pcf8563_write_block_data(struct i2c_client *client,
 113                                    unsigned char reg, unsigned char length,
 114                                    unsigned char *buf)
 115 {
 116         int i, err;
 117 
 118         for (i = 0; i < length; i++) {
 119                 unsigned char data[2] = { reg + i, buf[i] };
 120 
 121                 err = i2c_master_send(client, data, sizeof(data));
 122                 if (err != sizeof(data)) {
 123                         dev_err(&client->dev,
 124                                 "%s: err=%d addr=%02x, data=%02x\n",
 125                                 __func__, err, data[0], data[1]);
 126                         return -EIO;
 127                 }
 128         }
 129 
 130         return 0;
 131 }
 132 
 133 static int pcf8563_set_alarm_mode(struct i2c_client *client, bool on)
 134 {
 135         unsigned char buf;
 136         int err;
 137 
 138         err = pcf8563_read_block_data(client, PCF8563_REG_ST2, 1, &buf);
 139         if (err < 0)
 140                 return err;
 141 
 142         if (on)
 143                 buf |= PCF8563_BIT_AIE;
 144         else
 145                 buf &= ~PCF8563_BIT_AIE;
 146 
 147         buf &= ~(PCF8563_BIT_AF | PCF8563_BITS_ST2_N);
 148 
 149         err = pcf8563_write_block_data(client, PCF8563_REG_ST2, 1, &buf);
 150         if (err < 0) {
 151                 dev_err(&client->dev, "%s: write error\n", __func__);
 152                 return -EIO;
 153         }
 154 
 155         return 0;
 156 }
 157 
 158 static int pcf8563_get_alarm_mode(struct i2c_client *client, unsigned char *en,
 159                                   unsigned char *pen)
 160 {
 161         unsigned char buf;
 162         int err;
 163 
 164         err = pcf8563_read_block_data(client, PCF8563_REG_ST2, 1, &buf);
 165         if (err)
 166                 return err;
 167 
 168         if (en)
 169                 *en = !!(buf & PCF8563_BIT_AIE);
 170         if (pen)
 171                 *pen = !!(buf & PCF8563_BIT_AF);
 172 
 173         return 0;
 174 }
 175 
 176 static irqreturn_t pcf8563_irq(int irq, void *dev_id)
 177 {
 178         struct pcf8563 *pcf8563 = i2c_get_clientdata(dev_id);
 179         int err;
 180         char pending;
 181 
 182         err = pcf8563_get_alarm_mode(pcf8563->client, NULL, &pending);
 183         if (err)
 184                 return IRQ_NONE;
 185 
 186         if (pending) {
 187                 rtc_update_irq(pcf8563->rtc, 1, RTC_IRQF | RTC_AF);
 188                 pcf8563_set_alarm_mode(pcf8563->client, 1);
 189                 return IRQ_HANDLED;
 190         }
 191 
 192         return IRQ_NONE;
 193 }
 194 
 195 /*
 196  * In the routines that deal directly with the pcf8563 hardware, we use
 197  * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch.
 198  */
 199 static int pcf8563_rtc_read_time(struct device *dev, struct rtc_time *tm)
 200 {
 201         struct i2c_client *client = to_i2c_client(dev);
 202         struct pcf8563 *pcf8563 = i2c_get_clientdata(client);
 203         unsigned char buf[9];
 204         int err;
 205 
 206         err = pcf8563_read_block_data(client, PCF8563_REG_ST1, 9, buf);
 207         if (err)
 208                 return err;
 209 
 210         if (buf[PCF8563_REG_SC] & PCF8563_SC_LV) {
 211                 pcf8563->voltage_low = 1;
 212                 dev_err(&client->dev,
 213                         "low voltage detected, date/time is not reliable.\n");
 214                 return -EINVAL;
 215         }
 216 
 217         dev_dbg(&client->dev,
 218                 "%s: raw data is st1=%02x, st2=%02x, sec=%02x, min=%02x, hr=%02x, "
 219                 "mday=%02x, wday=%02x, mon=%02x, year=%02x\n",
 220                 __func__,
 221                 buf[0], buf[1], buf[2], buf[3],
 222                 buf[4], buf[5], buf[6], buf[7],
 223                 buf[8]);
 224 
 225 
 226         tm->tm_sec = bcd2bin(buf[PCF8563_REG_SC] & 0x7F);
 227         tm->tm_min = bcd2bin(buf[PCF8563_REG_MN] & 0x7F);
 228         tm->tm_hour = bcd2bin(buf[PCF8563_REG_HR] & 0x3F); /* rtc hr 0-23 */
 229         tm->tm_mday = bcd2bin(buf[PCF8563_REG_DM] & 0x3F);
 230         tm->tm_wday = buf[PCF8563_REG_DW] & 0x07;
 231         tm->tm_mon = bcd2bin(buf[PCF8563_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */
 232         tm->tm_year = bcd2bin(buf[PCF8563_REG_YR]) + 100;
 233         /* detect the polarity heuristically. see note above. */
 234         pcf8563->c_polarity = (buf[PCF8563_REG_MO] & PCF8563_MO_C) ?
 235                 (tm->tm_year >= 100) : (tm->tm_year < 100);
 236 
 237         dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
 238                 "mday=%d, mon=%d, year=%d, wday=%d\n",
 239                 __func__,
 240                 tm->tm_sec, tm->tm_min, tm->tm_hour,
 241                 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
 242 
 243         return 0;
 244 }
 245 
 246 static int pcf8563_rtc_set_time(struct device *dev, struct rtc_time *tm)
 247 {
 248         struct i2c_client *client = to_i2c_client(dev);
 249         struct pcf8563 *pcf8563 = i2c_get_clientdata(client);
 250         unsigned char buf[9];
 251 
 252         dev_dbg(&client->dev, "%s: secs=%d, mins=%d, hours=%d, "
 253                 "mday=%d, mon=%d, year=%d, wday=%d\n",
 254                 __func__,
 255                 tm->tm_sec, tm->tm_min, tm->tm_hour,
 256                 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
 257 
 258         /* hours, minutes and seconds */
 259         buf[PCF8563_REG_SC] = bin2bcd(tm->tm_sec);
 260         buf[PCF8563_REG_MN] = bin2bcd(tm->tm_min);
 261         buf[PCF8563_REG_HR] = bin2bcd(tm->tm_hour);
 262 
 263         buf[PCF8563_REG_DM] = bin2bcd(tm->tm_mday);
 264 
 265         /* month, 1 - 12 */
 266         buf[PCF8563_REG_MO] = bin2bcd(tm->tm_mon + 1);
 267 
 268         /* year and century */
 269         buf[PCF8563_REG_YR] = bin2bcd(tm->tm_year - 100);
 270         if (pcf8563->c_polarity ? (tm->tm_year >= 100) : (tm->tm_year < 100))
 271                 buf[PCF8563_REG_MO] |= PCF8563_MO_C;
 272 
 273         buf[PCF8563_REG_DW] = tm->tm_wday & 0x07;
 274 
 275         return pcf8563_write_block_data(client, PCF8563_REG_SC,
 276                                 9 - PCF8563_REG_SC, buf + PCF8563_REG_SC);
 277 }
 278 
 279 #ifdef CONFIG_RTC_INTF_DEV
 280 static int pcf8563_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
 281 {
 282         struct pcf8563 *pcf8563 = i2c_get_clientdata(to_i2c_client(dev));
 283         struct rtc_time tm;
 284 
 285         switch (cmd) {
 286         case RTC_VL_READ:
 287                 if (pcf8563->voltage_low)
 288                         dev_info(dev, "low voltage detected, date/time is not reliable.\n");
 289 
 290                 if (copy_to_user((void __user *)arg, &pcf8563->voltage_low,
 291                                         sizeof(int)))
 292                         return -EFAULT;
 293                 return 0;
 294         case RTC_VL_CLR:
 295                 /*
 296                  * Clear the VL bit in the seconds register in case
 297                  * the time has not been set already (which would
 298                  * have cleared it). This does not really matter
 299                  * because of the cached voltage_low value but do it
 300                  * anyway for consistency.
 301                  */
 302                 if (pcf8563_rtc_read_time(dev, &tm))
 303                         pcf8563_rtc_set_time(dev, &tm);
 304 
 305                 /* Clear the cached value. */
 306                 pcf8563->voltage_low = 0;
 307 
 308                 return 0;
 309         default:
 310                 return -ENOIOCTLCMD;
 311         }
 312 }
 313 #else
 314 #define pcf8563_rtc_ioctl NULL
 315 #endif
 316 
 317 static int pcf8563_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *tm)
 318 {
 319         struct i2c_client *client = to_i2c_client(dev);
 320         unsigned char buf[4];
 321         int err;
 322 
 323         err = pcf8563_read_block_data(client, PCF8563_REG_AMN, 4, buf);
 324         if (err)
 325                 return err;
 326 
 327         dev_dbg(&client->dev,
 328                 "%s: raw data is min=%02x, hr=%02x, mday=%02x, wday=%02x\n",
 329                 __func__, buf[0], buf[1], buf[2], buf[3]);
 330 
 331         tm->time.tm_sec = 0;
 332         tm->time.tm_min = bcd2bin(buf[0] & 0x7F);
 333         tm->time.tm_hour = bcd2bin(buf[1] & 0x3F);
 334         tm->time.tm_mday = bcd2bin(buf[2] & 0x3F);
 335         tm->time.tm_wday = bcd2bin(buf[3] & 0x7);
 336 
 337         err = pcf8563_get_alarm_mode(client, &tm->enabled, &tm->pending);
 338         if (err < 0)
 339                 return err;
 340 
 341         dev_dbg(&client->dev, "%s: tm is mins=%d, hours=%d, mday=%d, wday=%d,"
 342                 " enabled=%d, pending=%d\n", __func__, tm->time.tm_min,
 343                 tm->time.tm_hour, tm->time.tm_mday, tm->time.tm_wday,
 344                 tm->enabled, tm->pending);
 345 
 346         return 0;
 347 }
 348 
 349 static int pcf8563_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *tm)
 350 {
 351         struct i2c_client *client = to_i2c_client(dev);
 352         unsigned char buf[4];
 353         int err;
 354 
 355         /* The alarm has no seconds, round up to nearest minute */
 356         if (tm->time.tm_sec) {
 357                 time64_t alarm_time = rtc_tm_to_time64(&tm->time);
 358 
 359                 alarm_time += 60 - tm->time.tm_sec;
 360                 rtc_time64_to_tm(alarm_time, &tm->time);
 361         }
 362 
 363         dev_dbg(dev, "%s, min=%d hour=%d wday=%d mday=%d "
 364                 "enabled=%d pending=%d\n", __func__,
 365                 tm->time.tm_min, tm->time.tm_hour, tm->time.tm_wday,
 366                 tm->time.tm_mday, tm->enabled, tm->pending);
 367 
 368         buf[0] = bin2bcd(tm->time.tm_min);
 369         buf[1] = bin2bcd(tm->time.tm_hour);
 370         buf[2] = bin2bcd(tm->time.tm_mday);
 371         buf[3] = tm->time.tm_wday & 0x07;
 372 
 373         err = pcf8563_write_block_data(client, PCF8563_REG_AMN, 4, buf);
 374         if (err)
 375                 return err;
 376 
 377         return pcf8563_set_alarm_mode(client, !!tm->enabled);
 378 }
 379 
 380 static int pcf8563_irq_enable(struct device *dev, unsigned int enabled)
 381 {
 382         dev_dbg(dev, "%s: en=%d\n", __func__, enabled);
 383         return pcf8563_set_alarm_mode(to_i2c_client(dev), !!enabled);
 384 }
 385 
 386 #ifdef CONFIG_COMMON_CLK
 387 /*
 388  * Handling of the clkout
 389  */
 390 
 391 #define clkout_hw_to_pcf8563(_hw) container_of(_hw, struct pcf8563, clkout_hw)
 392 
 393 static int clkout_rates[] = {
 394         32768,
 395         1024,
 396         32,
 397         1,
 398 };
 399 
 400 static unsigned long pcf8563_clkout_recalc_rate(struct clk_hw *hw,
 401                                                 unsigned long parent_rate)
 402 {
 403         struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw);
 404         struct i2c_client *client = pcf8563->client;
 405         unsigned char buf;
 406         int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf);
 407 
 408         if (ret < 0)
 409                 return 0;
 410 
 411         buf &= PCF8563_REG_CLKO_F_MASK;
 412         return clkout_rates[buf];
 413 }
 414 
 415 static long pcf8563_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
 416                                       unsigned long *prate)
 417 {
 418         int i;
 419 
 420         for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
 421                 if (clkout_rates[i] <= rate)
 422                         return clkout_rates[i];
 423 
 424         return 0;
 425 }
 426 
 427 static int pcf8563_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
 428                                    unsigned long parent_rate)
 429 {
 430         struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw);
 431         struct i2c_client *client = pcf8563->client;
 432         unsigned char buf;
 433         int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf);
 434         int i;
 435 
 436         if (ret < 0)
 437                 return ret;
 438 
 439         for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
 440                 if (clkout_rates[i] == rate) {
 441                         buf &= ~PCF8563_REG_CLKO_F_MASK;
 442                         buf |= i;
 443                         ret = pcf8563_write_block_data(client,
 444                                                        PCF8563_REG_CLKO, 1,
 445                                                        &buf);
 446                         return ret;
 447                 }
 448 
 449         return -EINVAL;
 450 }
 451 
 452 static int pcf8563_clkout_control(struct clk_hw *hw, bool enable)
 453 {
 454         struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw);
 455         struct i2c_client *client = pcf8563->client;
 456         unsigned char buf;
 457         int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf);
 458 
 459         if (ret < 0)
 460                 return ret;
 461 
 462         if (enable)
 463                 buf |= PCF8563_REG_CLKO_FE;
 464         else
 465                 buf &= ~PCF8563_REG_CLKO_FE;
 466 
 467         ret = pcf8563_write_block_data(client, PCF8563_REG_CLKO, 1, &buf);
 468         return ret;
 469 }
 470 
 471 static int pcf8563_clkout_prepare(struct clk_hw *hw)
 472 {
 473         return pcf8563_clkout_control(hw, 1);
 474 }
 475 
 476 static void pcf8563_clkout_unprepare(struct clk_hw *hw)
 477 {
 478         pcf8563_clkout_control(hw, 0);
 479 }
 480 
 481 static int pcf8563_clkout_is_prepared(struct clk_hw *hw)
 482 {
 483         struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw);
 484         struct i2c_client *client = pcf8563->client;
 485         unsigned char buf;
 486         int ret = pcf8563_read_block_data(client, PCF8563_REG_CLKO, 1, &buf);
 487 
 488         if (ret < 0)
 489                 return ret;
 490 
 491         return !!(buf & PCF8563_REG_CLKO_FE);
 492 }
 493 
 494 static const struct clk_ops pcf8563_clkout_ops = {
 495         .prepare = pcf8563_clkout_prepare,
 496         .unprepare = pcf8563_clkout_unprepare,
 497         .is_prepared = pcf8563_clkout_is_prepared,
 498         .recalc_rate = pcf8563_clkout_recalc_rate,
 499         .round_rate = pcf8563_clkout_round_rate,
 500         .set_rate = pcf8563_clkout_set_rate,
 501 };
 502 
 503 static struct clk *pcf8563_clkout_register_clk(struct pcf8563 *pcf8563)
 504 {
 505         struct i2c_client *client = pcf8563->client;
 506         struct device_node *node = client->dev.of_node;
 507         struct clk *clk;
 508         struct clk_init_data init;
 509         int ret;
 510         unsigned char buf;
 511 
 512         /* disable the clkout output */
 513         buf = 0;
 514         ret = pcf8563_write_block_data(client, PCF8563_REG_CLKO, 1, &buf);
 515         if (ret < 0)
 516                 return ERR_PTR(ret);
 517 
 518         init.name = "pcf8563-clkout";
 519         init.ops = &pcf8563_clkout_ops;
 520         init.flags = 0;
 521         init.parent_names = NULL;
 522         init.num_parents = 0;
 523         pcf8563->clkout_hw.init = &init;
 524 
 525         /* optional override of the clockname */
 526         of_property_read_string(node, "clock-output-names", &init.name);
 527 
 528         /* register the clock */
 529         clk = devm_clk_register(&client->dev, &pcf8563->clkout_hw);
 530 
 531         if (!IS_ERR(clk))
 532                 of_clk_add_provider(node, of_clk_src_simple_get, clk);
 533 
 534         return clk;
 535 }
 536 #endif
 537 
 538 static const struct rtc_class_ops pcf8563_rtc_ops = {
 539         .ioctl          = pcf8563_rtc_ioctl,
 540         .read_time      = pcf8563_rtc_read_time,
 541         .set_time       = pcf8563_rtc_set_time,
 542         .read_alarm     = pcf8563_rtc_read_alarm,
 543         .set_alarm      = pcf8563_rtc_set_alarm,
 544         .alarm_irq_enable = pcf8563_irq_enable,
 545 };
 546 
 547 static int pcf8563_probe(struct i2c_client *client,
 548                                 const struct i2c_device_id *id)
 549 {
 550         struct pcf8563 *pcf8563;
 551         int err;
 552         unsigned char buf;
 553 
 554         dev_dbg(&client->dev, "%s\n", __func__);
 555 
 556         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
 557                 return -ENODEV;
 558 
 559         pcf8563 = devm_kzalloc(&client->dev, sizeof(struct pcf8563),
 560                                 GFP_KERNEL);
 561         if (!pcf8563)
 562                 return -ENOMEM;
 563 
 564         i2c_set_clientdata(client, pcf8563);
 565         pcf8563->client = client;
 566         device_set_wakeup_capable(&client->dev, 1);
 567 
 568         /* Set timer to lowest frequency to save power (ref Haoyu datasheet) */
 569         buf = PCF8563_TMRC_1_60;
 570         err = pcf8563_write_block_data(client, PCF8563_REG_TMRC, 1, &buf);
 571         if (err < 0) {
 572                 dev_err(&client->dev, "%s: write error\n", __func__);
 573                 return err;
 574         }
 575 
 576         /* Clear flags and disable interrupts */
 577         buf = 0;
 578         err = pcf8563_write_block_data(client, PCF8563_REG_ST2, 1, &buf);
 579         if (err < 0) {
 580                 dev_err(&client->dev, "%s: write error\n", __func__);
 581                 return err;
 582         }
 583 
 584         pcf8563->rtc = devm_rtc_allocate_device(&client->dev);
 585         if (IS_ERR(pcf8563->rtc))
 586                 return PTR_ERR(pcf8563->rtc);
 587 
 588         pcf8563->rtc->ops = &pcf8563_rtc_ops;
 589         /* the pcf8563 alarm only supports a minute accuracy */
 590         pcf8563->rtc->uie_unsupported = 1;
 591         pcf8563->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 592         pcf8563->rtc->range_max = RTC_TIMESTAMP_END_2099;
 593         pcf8563->rtc->set_start_time = true;
 594 
 595         if (client->irq > 0) {
 596                 err = devm_request_threaded_irq(&client->dev, client->irq,
 597                                 NULL, pcf8563_irq,
 598                                 IRQF_SHARED | IRQF_ONESHOT | IRQF_TRIGGER_LOW,
 599                                 pcf8563_driver.driver.name, client);
 600                 if (err) {
 601                         dev_err(&client->dev, "unable to request IRQ %d\n",
 602                                                                 client->irq);
 603                         return err;
 604                 }
 605         }
 606 
 607         err = rtc_register_device(pcf8563->rtc);
 608         if (err)
 609                 return err;
 610 
 611 #ifdef CONFIG_COMMON_CLK
 612         /* register clk in common clk framework */
 613         pcf8563_clkout_register_clk(pcf8563);
 614 #endif
 615 
 616         return 0;
 617 }
 618 
 619 static const struct i2c_device_id pcf8563_id[] = {
 620         { "pcf8563", 0 },
 621         { "rtc8564", 0 },
 622         { }
 623 };
 624 MODULE_DEVICE_TABLE(i2c, pcf8563_id);
 625 
 626 #ifdef CONFIG_OF
 627 static const struct of_device_id pcf8563_of_match[] = {
 628         { .compatible = "nxp,pcf8563" },
 629         { .compatible = "epson,rtc8564" },
 630         { .compatible = "microcrystal,rv8564" },
 631         {}
 632 };
 633 MODULE_DEVICE_TABLE(of, pcf8563_of_match);
 634 #endif
 635 
 636 static struct i2c_driver pcf8563_driver = {
 637         .driver         = {
 638                 .name   = "rtc-pcf8563",
 639                 .of_match_table = of_match_ptr(pcf8563_of_match),
 640         },
 641         .probe          = pcf8563_probe,
 642         .id_table       = pcf8563_id,
 643 };
 644 
 645 module_i2c_driver(pcf8563_driver);
 646 
 647 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
 648 MODULE_DESCRIPTION("Philips PCF8563/Epson RTC8564 RTC driver");
 649 MODULE_LICENSE("GPL");
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/rtc/rtc-pcf8563.c

DEFINITIONS
