target/linux/coldfire/patches/027-Add-RTC-driver-support-on-MCF5441x-platform.patch

   1 From 6462d09dad154b69ea6180c0acb2d009627ff1be Mon Sep 17 00:00:00 2001
   2 From: Alison Wang <b18965@freescale.com>
   3 Date: Thu, 4 Aug 2011 09:59:46 +0800
   4 Subject: [PATCH 27/52] Add RTC driver support on MCF5441x platform
   5
   6 Support on-chip robust-RTC module on MCF5441x platform.
   7
   8 Signed-off-by: Alison Wang <b18965@freescale.com>
   9 ---
  10  drivers/rtc/Kconfig      |    9 +
  11  drivers/rtc/Makefile     |    1 +
  12  drivers/rtc/rtc-m5441x.c |  638 ++++++++++++++++++++++++++++++++++++++++++++++
  13  3 files changed, 648 insertions(+), 0 deletions(-)
  14  create mode 100644 drivers/rtc/rtc-m5441x.c
  15
  16 --- a/drivers/rtc/Kconfig
  17 +++ b/drivers/rtc/Kconfig
  18 @@ -928,6 +928,15 @@ config RTC_MCF
  19
  20           If you build it as a module it will be call mcf-rtc.
  21
  22 +config RTC_M5441X
  23 +        tristate "Freescale Coldfire M5441X platform Real Time Clock"
  24 +        depends on COLDFIRE
  25 +        help
  26 +          If you say yes here you will get support for the on-chip Coldfire
  27 +         Real-Time Clock for mcf5441x platform.
  28 +
  29 +         If you build it as a module it will be call rtc-m5441x.
  30 +
  31  config RTC_DRV_PS3
  32         tristate "PS3 RTC"
  33         depends on PPC_PS3
  34 --- a/drivers/rtc/Makefile
  35 +++ b/drivers/rtc/Makefile
  36 @@ -103,3 +103,4 @@ obj-$(CONFIG_RTC_DRV_WM831X)        += rtc-wm83
  37  obj-$(CONFIG_RTC_DRV_WM8350)   += rtc-wm8350.o
  38  obj-$(CONFIG_RTC_DRV_X1205)    += rtc-x1205.o
  39  obj-$(CONFIG_RTC_MCF)           += rtc-mcf.o
  40 +obj-$(CONFIG_RTC_M5441X)       += rtc-m5441x.o
  41 --- /dev/null
  42 +++ b/drivers/rtc/rtc-m5441x.c
  43 @@ -0,0 +1,638 @@
  44 +/*
  45 + * Copyright (C) 2010-2011 Freescale Semiconductor, Inc. All Rights Reserved.
  46 + *
  47 + * Lanttor.Guo@freescale.com
  48 + *
  49 + * The code contained herein is licensed under the GNU General Public
  50 + * License. You may obtain a copy of the GNU General Public License
  51 + * Version 2 or later at the following locations:
  52 + *
  53 + * http://www.opensource.org/licenses/gpl-license.html
  54 + * http://www.gnu.org/copyleft/gpl.html
  55 + */
  56 +
  57 +/*
  58 + * Implementation based on rtc-mcf.c
  59 + */
  60 +
  61 +/*
  62 + * RTC Real Time Clock (RTC) Driver
  63 + *
  64 + * @file rtc-m5441x.c
  65 + * @brief Real Time Clock interface
  66 + *
  67 + * This file contains Real Time Clock interface for Linux.
  68 + *
  69 + */
  70 +#include <linux/rtc.h>
  71 +#include <linux/module.h>
  72 +#include <linux/fs.h>
  73 +#include <linux/init.h>
  74 +#include <linux/interrupt.h>
  75 +#include <linux/platform_device.h>
  76 +#include <linux/clk.h>
  77 +#include <linux/uaccess.h>
  78 +#include <asm/mcfsim.h>
  79 +#include <linux/slab.h>
  80 +#include <linux/io.h>
  81 +
  82 +#ifdef readw
  83 +#undef readw
  84 +#endif
  85 +
  86 +#ifdef writew
  87 +#undef writew
  88 +#endif
  89 +
  90 +#define readw(addr)      in_be16(addr)
  91 +#define writew(val, addr) out_be16((addr), (val))
  92 +
  93 +
  94 +#define PIT_ALL_ON (MCF_RTC_ISR_2HZ | MCF_RTC_ISR_SAM0 | MCF_RTC_ISR_SAM1 | \
  95 +                    MCF_RTC_ISR_SAM2 | MCF_RTC_ISR_SAM3 | MCF_RTC_ISR_SAM4 | \
  96 +                    MCF_RTC_ISR_SAM5 | MCF_RTC_ISR_SAM6 | MCF_RTC_ISR_SAM7)
  97 +
  98 +#define MAX_PIE_NUM     9
  99 +#define MAX_PIE_FREQ    512
 100 +const u32 PIE_BIT_DEF[MAX_PIE_NUM][2] = {
 101 +       {2,   MCF_RTC_ISR_2HZ},
 102 +       {4,   MCF_RTC_ISR_SAM0},
 103 +       {8,   MCF_RTC_ISR_SAM1},
 104 +       {16,  MCF_RTC_ISR_SAM2},
 105 +       {32,  MCF_RTC_ISR_SAM3},
 106 +       {64,  MCF_RTC_ISR_SAM4},
 107 +       {128, MCF_RTC_ISR_SAM5},
 108 +       {256, MCF_RTC_ISR_SAM6},
 109 +       {MAX_PIE_FREQ, MCF_RTC_ISR_SAM7},
 110 +};
 111 +
 112 +/* Those are the bits from a classic RTC we want to mimic */
 113 +#define RTC_IRQF                0x80   /* any of the following 3 is active */
 114 +#define RTC_PF                  0x40   /* Periodic interrupt */
 115 +#define RTC_AF                  0x20   /* Alarm interrupt */
 116 +#define RTC_UF                  0x10   /* Update interrupt for 1Hz RTC */
 117 +
 118 +#define MCF_RTC_TIME            0
 119 +#define MCF_RTC_ALARM           1
 120 +
 121 +struct rtc_plat_data {
 122 +       struct rtc_device *rtc;
 123 +       int irq;
 124 +       unsigned int irqen;
 125 +       int alrm_sec;
 126 +       int alrm_min;
 127 +       int alrm_hour;
 128 +       int alrm_mday;
 129 +};
 130 +
 131 +static const int year_cal_basic = 2112;
 132 +
 133 +#define RTC_VERSION            "0.1"
 134 +
 135 +static u32 rtc_freq = 2;       /* minimun value for PIE */
 136 +static unsigned long rtc_status;
 137 +
 138 +static struct rtc_time g_rtc_alarm = {
 139 +       .tm_year = 0,
 140 +       .tm_mon = 0,
 141 +       .tm_mday = 0,
 142 +       .tm_hour = 0,
 143 +       .tm_mon = 0,
 144 +       .tm_sec = 0,
 145 +};
 146 +
 147 +static DEFINE_SPINLOCK(rtc_lock);
 148 +
 149 +
 150 +/*
 151 + * This funciton is used to disable RTC register write protection
 152 + */
 153 +static void disable_register_write_protection(void)
 154 +{
 155 +       if (readw(MCF_RTC_SR) & MCF_RTC_SR_WPE) {
 156 +               writew(0x0000, MCF_RTC_CR);
 157 +               writew(0x0001, MCF_RTC_CR);
 158 +               writew(0x0003, MCF_RTC_CR);
 159 +               writew(0x0002, MCF_RTC_CR);
 160 +       }
 161 +
 162 +}
 163 +
 164 +/*
 165 + * This function is used to obtain the RTC time or the alarm value in
 166 + * second.
 167 + *
 168 + * @param  time_alarm   use MCF_RTC_TIME for RTC time value;
 169 + *                         MCF_RTC_ALARM for alarm value
 170 + *
 171 + * @return The RTC time or alarm time in second.
 172 + */
 173 +static u32 get_alarm_or_time(struct device *dev, int time_alarm,
 174 +                       struct rtc_time *tm)
 175 +{
 176 +       dev_dbg(dev, "debug function %s()!\n", __func__);
 177 +
 178 +       if (time_alarm == MCF_RTC_TIME) {
 179 +               /*check register information */
 180 +               dev_dbg(dev, "RTC_YEARMON:0x%x,RTC_DAYS:0x%x,RTC_HOURMIN:0x%x,"
 181 +                       "RTC_SECONDS:0x%x\n", readw(MCF_RTC_YEARMON),
 182 +                       readw(MCF_RTC_DAYS), readw(MCF_RTC_HOURMIN),
 183 +                       readw(MCF_RTC_SECONDS));
 184 +
 185 +               /* get year */
 186 +               tm->tm_year = year_cal_basic +
 187 +                       (char)(MCF_RTC_YEARMON_YEAR_RD(readw(MCF_RTC_YEARMON)));
 188 +               /* get month */
 189 +               tm->tm_mon =
 190 +                       MCF_RTC_YEARMON_MON_RD(readw(MCF_RTC_YEARMON)) - 1;
 191 +               /* get month day */
 192 +               tm->tm_mday = MCF_RTC_DAYS_DAY_RD(readw(MCF_RTC_DAYS));
 193 +               /* get year day */
 194 +               tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon,
 195 +                               tm->tm_year);
 196 +               /* year minus 1900 */
 197 +               tm->tm_year = tm->tm_year - 1900;
 198 +               /* get week day */
 199 +               tm->tm_wday = MCF_RTC_DAYS_DAYWEEK_RD(readw(MCF_RTC_DAYS));
 200 +               /* get hours */
 201 +               tm->tm_hour =
 202 +                       MCF_RTC_HOURMIN_HOURS_RD(readw(MCF_RTC_HOURMIN));
 203 +               /* get minutes */
 204 +               tm->tm_min =
 205 +                       MCF_RTC_HOURMIN_MINUTES_RD(readw(MCF_RTC_HOURMIN));
 206 +               /* get seconds */
 207 +               tm->tm_sec =
 208 +                       MCF_RTC_SECONDS_SECONDS_RD(readw(MCF_RTC_SECONDS));
 209 +               /* no day saving time */
 210 +               tm->tm_isdst = -1;
 211 +
 212 +               /* check rtc_tm fileds information */
 213 +               dev_dbg(dev, "RTC TIME --> year:%d,yday:%d,mon:%d,mday:%d,"
 214 +                       "wday:%d,hour:%d,min:%d,sec:%d\n", tm->tm_year,
 215 +                       tm->tm_yday, tm->tm_mon, tm->tm_mday, tm->tm_wday,
 216 +                       tm->tm_hour, tm->tm_min, tm->tm_sec);
 217 +
 218 +       } else if (time_alarm == MCF_RTC_ALARM) {
 219 +               tm->tm_year = year_cal_basic +
 220 +                       (char)MCF_RTC_YEARMON_YEAR_RD
 221 +                       (readw(MCF_RTC_ALRM_YRMON));
 222 +               tm->tm_mon =
 223 +                       MCF_RTC_YEARMON_MON_RD(readw(MCF_RTC_ALRM_YRMON)) - 1;
 224 +               tm->tm_mday = MCF_RTC_DAYS_DAY_RD(readw(MCF_RTC_ALRM_DAYS));
 225 +               tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon,
 226 +                       tm->tm_year);
 227 +               tm->tm_year = tm->tm_year - 1900;
 228 +               tm->tm_wday =
 229 +                       MCF_RTC_DAYS_DAYWEEK_RD(readw(MCF_RTC_ALRM_DAYS));
 230 +               tm->tm_hour =
 231 +                       MCF_RTC_HOURMIN_HOURS_RD(readw(MCF_RTC_ALRM_HM));
 232 +               tm->tm_min =
 233 +                       MCF_RTC_HOURMIN_MINUTES_RD(readw(MCF_RTC_ALRM_HM));
 234 +               tm->tm_sec =
 235 +                       MCF_RTC_SECONDS_SECONDS_RD(readw(MCF_RTC_ALRM_SEC));
 236 +               tm->tm_isdst = -1;
 237 +
 238 +               /* debug information */
 239 +               dev_dbg(dev, "RTC ALARM --> year:%d,yday:%d,mon:%d,mday:%d,"
 240 +                       "wday:%d,hour:%d,min:%d,sec:%d\n", tm->tm_year,
 241 +                       tm->tm_yday, tm->tm_mon, tm->tm_mday, tm->tm_wday,
 242 +                       tm->tm_hour, tm->tm_min, tm->tm_sec);
 243 +
 244 +       } else {
 245 +               panic("wrong value for time_alarm=%d\n", time_alarm);
 246 +       }
 247 +
 248 +       return 0;
 249 +}
 250 +
 251 +/*
 252 + * This function sets the RTC alarm value or the time value.
 253 + *
 254 + * @param  time_alarm  the new alarm value to be updated in the RTC
 255 + * @param  time        use MCF_RTC_TIME for RTC time value;
 256 + *                     MCF_RTC_ALARM for alarm value
 257 + */
 258 +static void set_alarm_or_time(struct device *dev, int time_alarm,
 259 +                       struct rtc_time *tm)
 260 +{
 261 +       char year;
 262 +
 263 +       dev_dbg(dev, "debug function %s()!\n", __func__);
 264 +
 265 +       /* wirte enable setting */
 266 +       disable_register_write_protection();
 267 +
 268 +       if (time_alarm == MCF_RTC_TIME) {
 269 +               /* check rtc_time fields information */
 270 +               dev_dbg(dev, "RTC TIME --> year:%d,yday:%d,mon:%d,mday:%d,"
 271 +                       "wday:%d,hour:%d,min:%d,sec:%d\n", tm->tm_year,
 272 +                       tm->tm_yday, tm->tm_mon, tm->tm_mday, tm->tm_wday,
 273 +                       tm->tm_hour, tm->tm_min, tm->tm_sec);
 274 +
 275 +               year = ((tm->tm_year + 1900) - year_cal_basic);
 276 +               /* write RTC_YEARMON register */
 277 +               writew((year << 8) | (tm->tm_mon + 1), MCF_RTC_YEARMON);
 278 +
 279 +               /* write RTC_DAYS register */
 280 +               writew(MCF_RTC_DAYS_DAYWEEK_SET(tm->tm_wday) |
 281 +                       MCF_RTC_DAYS_DAY_SET(tm->tm_mday), MCF_RTC_DAYS);
 282 +
 283 +               /* write RTC_HOURMIN register */
 284 +               writew(MCF_RTC_HOURMIN_HOURS_SET(tm->tm_hour) |
 285 +                       MCF_RTC_HOURMIN_MINUTES_SET(tm->tm_min),
 286 +                       MCF_RTC_HOURMIN);
 287 +
 288 +               /* write RTC_SECONDS register */
 289 +               writew(MCF_RTC_SECONDS_SECONDS_SET
 290 +                       (tm->tm_sec), MCF_RTC_SECONDS);
 291 +
 292 +               /* debug information */
 293 +               dev_dbg(dev, "RTC_YEARMON:0x%x, RTC_DAYS:0x%x, "
 294 +                       "RTC_HOURMIN:0x%x, RTC_SECONDS:0x%x\n",
 295 +                       readw(MCF_RTC_YEARMON), readw(MCF_RTC_DAYS),
 296 +                       readw(MCF_RTC_HOURMIN), readw(MCF_RTC_SECONDS));
 297 +       } else if (time_alarm == MCF_RTC_ALARM) {
 298 +
 299 +               year = ((tm->tm_year + 1900) - year_cal_basic);
 300 +               /* write RTC_YEARMON register */
 301 +               writew((year << 8) | (tm->tm_mon + 1), MCF_RTC_ALRM_YRMON);
 302 +
 303 +               /* write RTC_DAYS register */
 304 +               writew(MCF_RTC_DAYS_DAYWEEK_SET(tm->tm_wday) |
 305 +                       MCF_RTC_DAYS_DAY_SET(tm->tm_mday), MCF_RTC_ALRM_DAYS);
 306 +
 307 +               /* write RTC_HOURMIN register */
 308 +               writew(MCF_RTC_HOURMIN_HOURS_SET(tm->tm_hour) |
 309 +                       MCF_RTC_HOURMIN_MINUTES_SET(tm->tm_min),
 310 +                       MCF_RTC_ALRM_HM);
 311 +
 312 +               /* write RTC_SECONDS register */
 313 +               writew(MCF_RTC_SECONDS_SECONDS_SET
 314 +                       (tm->tm_sec), MCF_RTC_ALRM_SEC);
 315 +
 316 +               /* debug information */
 317 +               dev_dbg(dev, "ALRM_YRMON:0x%x,ALRM_DAYS:0x%x,ALRM_HM:0x%x,"
 318 +                       "ALRM_SEC:0x%x\n", readw(MCF_RTC_ALRM_YRMON),
 319 +                       readw(MCF_RTC_ALRM_DAYS), readw(MCF_RTC_ALRM_HM),
 320 +                       readw(MCF_RTC_ALRM_SEC));
 321 +       } else {
 322 +               panic("wrong value for time_alarm=%d\n", time_alarm);
 323 +       }
 324 +}
 325 +
 326 +/*!
 327 + * This function updates the RTC alarm registers and then clears all the
 328 + * interrupt status bits.
 329 + *
 330 + * @param  alrm         the new alarm value to be updated in the RTC
 331 + *
 332 + * @return  0 if successful; non-zero otherwise.
 333 + */
 334 +static int rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
 335 +{
 336 +       /* clear all the interrupt status bits */
 337 +       disable_register_write_protection();
 338 +
 339 +       writew(readw(MCF_RTC_ISR), MCF_RTC_ISR);
 340 +
 341 +       set_alarm_or_time(dev, MCF_RTC_ALARM, alrm);
 342 +
 343 +       return 0;
 344 +}
 345 +
 346 +/*!
 347 + * This function is the RTC interrupt service routine.
 348 + *
 349 + * @param  irq          RTC IRQ number
 350 + * @param  dev_id       device ID which is not used
 351 + *
 352 + * @return IRQ_HANDLED as defined in the include/linux/interrupt.h file.
 353 + */
 354 +static irqreturn_t mcf_rtc_interrupt(int irq, void *dev_id)
 355 +{
 356 +       struct platform_device *pdev = dev_id;
 357 +       struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
 358 +       u16 status = 0;
 359 +       u32 events = 0;
 360 +
 361 +       spin_lock(&rtc_lock);
 362 +
 363 +       /* clear interrupt sources */
 364 +       status = readw(MCF_RTC_ISR) & readw(MCF_RTC_IER);
 365 +
 366 +       disable_register_write_protection();
 367 +
 368 +       writew(status, MCF_RTC_ISR);
 369 +
 370 +       /* clear alarm interrupt if it has occurred */
 371 +       if (status & MCF_RTC_ISR_ALM)
 372 +               status &= ~MCF_RTC_ISR_ALM;
 373 +
 374 +       /* update irq data & counter */
 375 +       if (status & MCF_RTC_ISR_ALM)
 376 +               events |= (RTC_AF | RTC_IRQF);
 377 +       if (status & MCF_RTC_ISR_1HZ)
 378 +               events |= (RTC_UF | RTC_IRQF);
 379 +       if (status & PIT_ALL_ON)
 380 +               events |= (RTC_PF | RTC_IRQF);
 381 +
 382 +       if ((status & MCF_RTC_ISR_ALM) && rtc_valid_tm(&g_rtc_alarm))
 383 +               rtc_update_alarm(&pdev->dev, &g_rtc_alarm);
 384 +
 385 +       spin_unlock(&rtc_lock);
 386 +       rtc_update_irq(pdata->rtc, 1, events);
 387 +       return IRQ_HANDLED;
 388 +}
 389 +
 390 +/*!
 391 + * clear all interrupts and release the IRQ
 392 + */
 393 +static void mcf_rtc_release(struct device *dev)
 394 +{
 395 +       spin_lock_irq(&rtc_lock);
 396 +
 397 +       disable_register_write_protection();
 398 +
 399 +       writew(0, MCF_RTC_IER);                 /* Disable all rtc interrupts */
 400 +       writew(readw(MCF_RTC_ISR), MCF_RTC_ISR);
 401 +       spin_unlock_irq(&rtc_lock);
 402 +       rtc_status = 0;
 403 +}
 404 +
 405 +/*!
 406 + * This function is used to support some ioctl calls directly.
 407 + * Other ioctl calls are supported indirectly through the
 408 + * arm/common/rtctime.c file.
 409 + *
 410 + * @param  cmd          ioctl command as defined in include/linux/rtc.h
 411 + * @param  arg          value for the ioctl command
 412 + *
 413 + * @return  0 if successful or negative value otherwise.
 414 + */
 415 +static int mcf_rtc_ioctl(struct device *dev, unsigned int cmd,
 416 +                        unsigned long arg)
 417 +{
 418 +       int i;
 419 +
 420 +       disable_register_write_protection();
 421 +
 422 +       switch (cmd) {
 423 +       case RTC_PIE_OFF:
 424 +               writew((readw(MCF_RTC_IER) & ~PIT_ALL_ON), MCF_RTC_IER);
 425 +               return 0;
 426 +       case RTC_IRQP_SET:
 427 +               if (arg < 2 || arg > MAX_PIE_FREQ || (arg % 2) != 0)
 428 +                       return -EINVAL; /* Also make sure a power of 2Hz */
 429 +               if ((arg > 64) && (!capable(CAP_SYS_RESOURCE)))
 430 +                       return -EACCES;
 431 +               rtc_freq = arg;
 432 +               return 0;
 433 +       case RTC_IRQP_READ:
 434 +               return put_user(rtc_freq, (u32 *) arg);
 435 +       case RTC_PIE_ON:
 436 +               for (i = 0; i < MAX_PIE_NUM; i++) {
 437 +                       if (PIE_BIT_DEF[i][0] == rtc_freq)
 438 +                               break;
 439 +               }
 440 +               if (i == MAX_PIE_NUM)
 441 +                       return -EACCES;
 442 +               spin_lock_irq(&rtc_lock);
 443 +               writew((readw(MCF_RTC_IER) | PIE_BIT_DEF[i][1]), MCF_RTC_IER);
 444 +               spin_unlock_irq(&rtc_lock);
 445 +               return 0;
 446 +       case RTC_AIE_OFF:
 447 +               spin_lock_irq(&rtc_lock);
 448 +               writew((readw(MCF_RTC_IER) & ~MCF_RTC_ISR_ALM), MCF_RTC_IER);
 449 +               spin_unlock_irq(&rtc_lock);
 450 +               return 0;
 451 +
 452 +       case RTC_AIE_ON:
 453 +               spin_lock_irq(&rtc_lock);
 454 +               writew((readw(MCF_RTC_IER) | MCF_RTC_ISR_ALM), MCF_RTC_IER);
 455 +               spin_unlock_irq(&rtc_lock);
 456 +               return 0;
 457 +
 458 +       case RTC_UIE_OFF:       /* UIE is for the 1Hz interrupt */
 459 +               spin_lock_irq(&rtc_lock);
 460 +               writew((readw(MCF_RTC_IER) & ~MCF_RTC_ISR_1HZ), MCF_RTC_IER);
 461 +               spin_unlock_irq(&rtc_lock);
 462 +               return 0;
 463 +
 464 +       case RTC_UIE_ON:
 465 +               spin_lock_irq(&rtc_lock);
 466 +               writew((readw(MCF_RTC_IER) | MCF_RTC_ISR_1HZ), MCF_RTC_IER);
 467 +               spin_unlock_irq(&rtc_lock);
 468 +               return 0;
 469 +       }
 470 +       return -ENOIOCTLCMD;
 471 +}
 472 +
 473 +/*!
 474 + * This function reads the current RTC time into tm in Gregorian date.
 475 + *
 476 + * @param  tm           contains the RTC time value upon return
 477 + *
 478 + * @return  0 if successful; non-zero otherwise.
 479 + */
 480 +static int mcf_rtc_read_time(struct device *dev, struct rtc_time *tm)
 481 +{
 482 +       do {
 483 +               get_alarm_or_time(dev, MCF_RTC_TIME, tm);
 484 +       } while (0);
 485 +
 486 +       return 0;
 487 +}
 488 +
 489 +/*!
 490 + * This function sets the internal RTC time based on tm in Gregorian date.
 491 + *
 492 + * @param  tm           the time value to be set in the RTC
 493 + *
 494 + * @return  0 if successful; non-zero otherwise.
 495 + */
 496 +static int mcf_rtc_set_time(struct device *dev, struct rtc_time *tm)
 497 +{
 498 +       do {
 499 +               set_alarm_or_time(dev, MCF_RTC_TIME, tm);
 500 +       } while (0);
 501 +
 502 +       return 0;
 503 +}
 504 +
 505 +/*!
 506 + * This function reads the current alarm value into the passed in \b alrm
 507 + * argument. It updates the \b alrm's pending field value based on the whether
 508 + * an alarm interrupt occurs or not.
 509 + *
 510 + * @param  alrm         contains the RTC alarm value upon return
 511 + *
 512 + * @return  0 if successful; non-zero otherwise.
 513 + */
 514 +static int mcf_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 515 +{
 516 +       do {
 517 +               get_alarm_or_time(dev, MCF_RTC_ALARM, &alrm->time);
 518 +       } while (0);
 519 +
 520 +       alrm->pending = ((readw(MCF_RTC_ISR) & MCF_RTC_ISR_ALM) != 0) ? 1 : 0;
 521 +
 522 +       return 0;
 523 +}
 524 +
 525 +/*!
 526 + * This function sets the RTC alarm based on passed in alrm.
 527 + *
 528 + * @param  alrm         the alarm value to be set in the RTC
 529 + *
 530 + * @return  0 if successful; non-zero otherwise.
 531 + */
 532 +static int mcf_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 533 +{
 534 +       int ret;
 535 +
 536 +       spin_lock_irq(&rtc_lock);
 537 +
 538 +       disable_register_write_protection();
 539 +
 540 +       if (rtc_valid_tm(&alrm->time)) {
 541 +               if (alrm->time.tm_sec > 59 ||
 542 +                   alrm->time.tm_hour > 23 || alrm->time.tm_min > 59) {
 543 +                       ret = -EINVAL;
 544 +                       goto out;
 545 +               }
 546 +               ret = rtc_update_alarm(dev, &alrm->time);
 547 +       } else {
 548 +               ret = rtc_valid_tm(&alrm->time);
 549 +               if (ret)
 550 +                       goto out;
 551 +               ret = rtc_update_alarm(dev, &alrm->time);
 552 +       }
 553 +
 554 +       if (ret == 0) {
 555 +               memcpy(&g_rtc_alarm, &alrm->time, sizeof(struct rtc_time));
 556 +
 557 +               if (alrm->enabled) {
 558 +                       writew((readw(MCF_RTC_IER) | MCF_RTC_ISR_ALM),
 559 +                               MCF_RTC_IER);
 560 +               } else {
 561 +                       writew((readw(MCF_RTC_IER) & ~MCF_RTC_ISR_ALM),
 562 +                               MCF_RTC_IER);
 563 +               }
 564 +       }
 565 +out:
 566 +       spin_unlock_irq(&rtc_lock);
 567 +
 568 +       return ret;
 569 +}
 570 +
 571 +/*!
 572 + * The RTC driver structure
 573 + */
 574 +static struct rtc_class_ops mcf_rtc_ops = {
 575 +       .ioctl = mcf_rtc_ioctl,
 576 +       .read_time = mcf_rtc_read_time,
 577 +       .set_time = mcf_rtc_set_time,
 578 +       .read_alarm = mcf_rtc_read_alarm,
 579 +       .set_alarm = mcf_rtc_set_alarm,
 580 +};
 581 +
 582 +static int __devinit mcf_rtc_probe(struct platform_device *pdev)
 583 +{
 584 +       struct rtc_device *rtc;
 585 +       struct rtc_plat_data *pdata = NULL;
 586 +       u32 ret = 0;
 587 +
 588 +       disable_register_write_protection();
 589 +       /* Clear interrupt before request irq */
 590 +       writew(0x0100, MCF_RTC_CR);
 591 +       writew(0x0001, MCF_RTC_IER);
 592 +
 593 +       if (!(readw(MCF_RTC_CFG_DATA) & MCF_RTC_CFG_DATA_OSCEN))
 594 +               writew(MCF_RTC_CFG_DATA_OSCEN, MCF_RTC_CFG_DATA);
 595 +
 596 +       pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
 597 +       if (!pdata)
 598 +               return -ENOMEM;
 599 +
 600 +       pdata->irq = MCFINT_VECBASE + MCFINT_RTC;
 601 +       if (request_irq(pdata->irq, mcf_rtc_interrupt, IRQF_DISABLED,
 602 +                       pdev->name, pdev) < 0) {
 603 +               dev_warn(&pdev->dev, "interrupt not available.\n");
 604 +               pdata->irq = -1;
 605 +       }
 606 +
 607 +       if (test_and_set_bit(1, &rtc_status))
 608 +               return -EBUSY;
 609 +
 610 +       rtc = rtc_device_register(pdev->name, &pdev->dev, &mcf_rtc_ops,
 611 +                               THIS_MODULE);
 612 +       if (IS_ERR(rtc)) {
 613 +               ret = PTR_ERR(rtc);
 614 +               if (pdata->irq >= 0)
 615 +                       free_irq(pdata->irq, pdev);
 616 +               kfree(pdata);
 617 +               return ret;
 618 +       }
 619 +       pdata->rtc = rtc;
 620 +       platform_set_drvdata(pdev, pdata);
 621 +
 622 +       dev_dbg(&pdev->dev, "RTC_CR:0x%x, RTC_SR:0x%x\n", readw(MCF_RTC_CR),
 623 +               readw(MCF_RTC_SR));
 624 +
 625 +       printk(KERN_INFO "Real Time Clock Driver v%s\n", RTC_VERSION);
 626 +       return ret;
 627 +}
 628 +
 629 +static int __devexit mcf_rtc_remove(struct platform_device *pdev)
 630 +{
 631 +       struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
 632 +
 633 +       rtc_device_unregister(pdata->rtc);
 634 +       if (pdata->irq >= 0)
 635 +               free_irq(pdata->irq, pdev);
 636 +       kfree(pdata);
 637 +       mcf_rtc_release(NULL);
 638 +       return 0;
 639 +}
 640 +
 641 +/*!
 642 + * Contains pointers to the power management callback functions.
 643 + */
 644 +MODULE_ALIAS("rtc-m5441x");
 645 +static struct platform_driver mcf_rtc_driver = {
 646 +       .driver = {
 647 +                  .name = "rtc-m5441x",
 648 +                  .owner = THIS_MODULE,
 649 +                  },
 650 +       .probe  = mcf_rtc_probe,
 651 +       .remove = __devexit_p(mcf_rtc_remove),
 652 +};
 653 +
 654 +/*!
 655 + * This function creates the /proc/driver/rtc file and registers the device RTC
 656 + * in the /dev/misc directory. It also reads the RTC value from external source
 657 + * and setup the internal RTC properly.
 658 + *
 659 + * @return  -1 if RTC is failed to initialize; 0 is successful.
 660 + */
 661 +static int __init mcf_rtc_init(void)
 662 +{
 663 +       return platform_driver_register(&mcf_rtc_driver);
 664 +}
 665 +
 666 +/*!
 667 + * This function removes the /proc/driver/rtc file and un-registers the
 668 + * device RTC from the /dev/misc directory.
 669 + */
 670 +static void __exit mcf_rtc_exit(void)
 671 +{
 672 +       platform_driver_unregister(&mcf_rtc_driver);
 673 +
 674 +}
 675 +
 676 +module_init(mcf_rtc_init);
 677 +module_exit(mcf_rtc_exit);
 678 +
 679 +MODULE_AUTHOR("Freescale Semiconductor, Inc.");
 680 +MODULE_DESCRIPTION("Real Time Clock Driver (MCF)");
 681 +MODULE_LICENSE("GPL V2");