drivers/rtc/rtc-88pm80x.c

   1 /*
   2  * Real Time Clock driver for Marvell 88PM80x PMIC
   3  *
   4  * Copyright (c) 2012 Marvell International Ltd.
   5  *  Wenzeng Chen<wzch@marvell.com>
   6  *  Qiao Zhou <zhouqiao@marvell.com>
   7  *
   8  * This file is subject to the terms and conditions of the GNU General
   9  * Public License. See the file "COPYING" in the main directory of this
  10  * archive for more details.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/slab.h>
  25 #include <linux/regmap.h>
  26 #include <linux/mfd/core.h>
  27 #include <linux/mfd/88pm80x.h>
  28 #include <linux/rtc.h>
  29
  30 #define PM800_RTC_COUNTER1              (0xD1)
  31 #define PM800_RTC_COUNTER2              (0xD2)
  32 #define PM800_RTC_COUNTER3              (0xD3)
  33 #define PM800_RTC_COUNTER4              (0xD4)
  34 #define PM800_RTC_EXPIRE1_1             (0xD5)
  35 #define PM800_RTC_EXPIRE1_2             (0xD6)
  36 #define PM800_RTC_EXPIRE1_3             (0xD7)
  37 #define PM800_RTC_EXPIRE1_4             (0xD8)
  38 #define PM800_RTC_TRIM1                 (0xD9)
  39 #define PM800_RTC_TRIM2                 (0xDA)
  40 #define PM800_RTC_TRIM3                 (0xDB)
  41 #define PM800_RTC_TRIM4                 (0xDC)
  42 #define PM800_RTC_EXPIRE2_1             (0xDD)
  43 #define PM800_RTC_EXPIRE2_2             (0xDE)
  44 #define PM800_RTC_EXPIRE2_3             (0xDF)
  45 #define PM800_RTC_EXPIRE2_4             (0xE0)
  46
  47 #define PM800_POWER_DOWN_LOG1   (0xE5)
  48 #define PM800_POWER_DOWN_LOG2   (0xE6)
  49
  50 struct pm80x_rtc_info {
  51         struct pm80x_chip *chip;
  52         struct regmap *map;
  53         struct rtc_device *rtc_dev;
  54         struct device *dev;
  55         struct delayed_work calib_work;
  56
  57         int irq;
  58         int vrtc;
  59 };
  60
  61 static irqreturn_t rtc_update_handler(int irq, void *data)
  62 {
  63         struct pm80x_rtc_info *info = (struct pm80x_rtc_info *)data;
  64         int mask;
  65
  66         mask = PM800_ALARM | PM800_ALARM_WAKEUP;
  67         regmap_update_bits(info->map, PM800_RTC_CONTROL, mask | PM800_ALARM1_EN,
  68                            mask);
  69         rtc_update_irq(info->rtc_dev, 1, RTC_AF);
  70         return IRQ_HANDLED;
  71 }
  72
  73 static int pm80x_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
  74 {
  75         struct pm80x_rtc_info *info = dev_get_drvdata(dev);
  76
  77         if (enabled)
  78                 regmap_update_bits(info->map, PM800_RTC_CONTROL,
  79                                    PM800_ALARM1_EN, PM800_ALARM1_EN);
  80         else
  81                 regmap_update_bits(info->map, PM800_RTC_CONTROL,
  82                                    PM800_ALARM1_EN, 0);
  83         return 0;
  84 }
  85
  86 /*
  87  * Calculate the next alarm time given the requested alarm time mask
  88  * and the current time.
  89  */
  90 static void rtc_next_alarm_time(struct rtc_time *next, struct rtc_time *now,
  91                                 struct rtc_time *alrm)
  92 {
  93         unsigned long next_time;
  94         unsigned long now_time;
  95
  96         next->tm_year = now->tm_year;
  97         next->tm_mon = now->tm_mon;
  98         next->tm_mday = now->tm_mday;
  99         next->tm_hour = alrm->tm_hour;
 100         next->tm_min = alrm->tm_min;
 101         next->tm_sec = alrm->tm_sec;
 102
 103         rtc_tm_to_time(now, &now_time);
 104         rtc_tm_to_time(next, &next_time);
 105
 106         if (next_time < now_time) {
 107                 /* Advance one day */
 108                 next_time += 60 * 60 * 24;
 109                 rtc_time_to_tm(next_time, next);
 110         }
 111 }
 112
 113 static int pm80x_rtc_read_time(struct device *dev, struct rtc_time *tm)
 114 {
 115         struct pm80x_rtc_info *info = dev_get_drvdata(dev);
 116         unsigned char buf[4];
 117         unsigned long ticks, base, data;
 118         regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
 119         base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 120                 (buf[1] << 8) | buf[0];
 121         dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
 122
 123         /* load 32-bit read-only counter */
 124         regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
 125         data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 126                 (buf[1] << 8) | buf[0];
 127         ticks = base + data;
 128         dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
 129                 base, data, ticks);
 130         rtc_time_to_tm(ticks, tm);
 131         return 0;
 132 }
 133
 134 static int pm80x_rtc_set_time(struct device *dev, struct rtc_time *tm)
 135 {
 136         struct pm80x_rtc_info *info = dev_get_drvdata(dev);
 137         unsigned char buf[4];
 138         unsigned long ticks, base, data;
 139         if ((tm->tm_year < 70) || (tm->tm_year > 138)) {
 140                 dev_dbg(info->dev,
 141                         "Set time %d out of range. Please set time between 1970 to 2038.\n",
 142                         1900 + tm->tm_year);
 143                 return -EINVAL;
 144         }
 145         rtc_tm_to_time(tm, &ticks);
 146
 147         /* load 32-bit read-only counter */
 148         regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
 149         data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 150                 (buf[1] << 8) | buf[0];
 151         base = ticks - data;
 152         dev_dbg(info->dev, "set base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
 153                 base, data, ticks);
 154         buf[0] = base & 0xFF;
 155         buf[1] = (base >> 8) & 0xFF;
 156         buf[2] = (base >> 16) & 0xFF;
 157         buf[3] = (base >> 24) & 0xFF;
 158         regmap_raw_write(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
 159
 160         return 0;
 161 }
 162
 163 static int pm80x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 164 {
 165         struct pm80x_rtc_info *info = dev_get_drvdata(dev);
 166         unsigned char buf[4];
 167         unsigned long ticks, base, data;
 168         int ret;
 169
 170         regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
 171         base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 172                 (buf[1] << 8) | buf[0];
 173         dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
 174
 175         regmap_raw_read(info->map, PM800_RTC_EXPIRE1_1, buf, 4);
 176         data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 177                 (buf[1] << 8) | buf[0];
 178         ticks = base + data;
 179         dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
 180                 base, data, ticks);
 181
 182         rtc_time_to_tm(ticks, &alrm->time);
 183         regmap_read(info->map, PM800_RTC_CONTROL, &ret);
 184         alrm->enabled = (ret & PM800_ALARM1_EN) ? 1 : 0;
 185         alrm->pending = (ret & (PM800_ALARM | PM800_ALARM_WAKEUP)) ? 1 : 0;
 186         return 0;
 187 }
 188
 189 static int pm80x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 190 {
 191         struct pm80x_rtc_info *info = dev_get_drvdata(dev);
 192         struct rtc_time now_tm, alarm_tm;
 193         unsigned long ticks, base, data;
 194         unsigned char buf[4];
 195         int mask;
 196
 197         regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_ALARM1_EN, 0);
 198
 199         regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
 200         base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 201                 (buf[1] << 8) | buf[0];
 202         dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
 203
 204         /* load 32-bit read-only counter */
 205         regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
 206         data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 207                 (buf[1] << 8) | buf[0];
 208         ticks = base + data;
 209         dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
 210                 base, data, ticks);
 211
 212         rtc_time_to_tm(ticks, &now_tm);
 213         dev_dbg(info->dev, "%s, now time : %lu\n", __func__, ticks);
 214         rtc_next_alarm_time(&alarm_tm, &now_tm, &alrm->time);
 215         /* get new ticks for alarm in 24 hours */
 216         rtc_tm_to_time(&alarm_tm, &ticks);
 217         dev_dbg(info->dev, "%s, alarm time: %lu\n", __func__, ticks);
 218         data = ticks - base;
 219
 220         buf[0] = data & 0xff;
 221         buf[1] = (data >> 8) & 0xff;
 222         buf[2] = (data >> 16) & 0xff;
 223         buf[3] = (data >> 24) & 0xff;
 224         regmap_raw_write(info->map, PM800_RTC_EXPIRE1_1, buf, 4);
 225         if (alrm->enabled) {
 226                 mask = PM800_ALARM | PM800_ALARM_WAKEUP | PM800_ALARM1_EN;
 227                 regmap_update_bits(info->map, PM800_RTC_CONTROL, mask, mask);
 228         } else {
 229                 mask = PM800_ALARM | PM800_ALARM_WAKEUP | PM800_ALARM1_EN;
 230                 regmap_update_bits(info->map, PM800_RTC_CONTROL, mask,
 231                                    PM800_ALARM | PM800_ALARM_WAKEUP);
 232         }
 233         return 0;
 234 }
 235
 236 static const struct rtc_class_ops pm80x_rtc_ops = {
 237         .read_time = pm80x_rtc_read_time,
 238         .set_time = pm80x_rtc_set_time,
 239         .read_alarm = pm80x_rtc_read_alarm,
 240         .set_alarm = pm80x_rtc_set_alarm,
 241         .alarm_irq_enable = pm80x_rtc_alarm_irq_enable,
 242 };
 243
 244 #ifdef CONFIG_PM_SLEEP
 245 static int pm80x_rtc_suspend(struct device *dev)
 246 {
 247         return pm80x_dev_suspend(dev);
 248 }
 249
 250 static int pm80x_rtc_resume(struct device *dev)
 251 {
 252         return pm80x_dev_resume(dev);
 253 }
 254 #endif
 255
 256 static SIMPLE_DEV_PM_OPS(pm80x_rtc_pm_ops, pm80x_rtc_suspend, pm80x_rtc_resume);
 257
 258 static int pm80x_rtc_probe(struct platform_device *pdev)
 259 {
 260         struct pm80x_chip *chip = dev_get_drvdata(pdev->dev.parent);
 261         struct pm80x_rtc_pdata *pdata = dev_get_platdata(&pdev->dev);
 262         struct pm80x_rtc_info *info;
 263         struct device_node *node = pdev->dev.of_node;
 264         struct rtc_time tm;
 265         unsigned long ticks = 0;
 266         int ret;
 267
 268         if (!pdata && !node) {
 269                 dev_err(&pdev->dev,
 270                         "pm80x-rtc requires platform data or of_node\n");
 271                 return -EINVAL;
 272         }
 273
 274         if (!pdata) {
 275                 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 276                 if (!pdata) {
 277                         dev_err(&pdev->dev, "failed to allocate memory\n");
 278                         return -ENOMEM;
 279                 }
 280         }
 281
 282         info =
 283             devm_kzalloc(&pdev->dev, sizeof(struct pm80x_rtc_info), GFP_KERNEL);
 284         if (!info)
 285                 return -ENOMEM;
 286         info->irq = platform_get_irq(pdev, 0);
 287         if (info->irq < 0) {
 288                 dev_err(&pdev->dev, "No IRQ resource!\n");
 289                 ret = -EINVAL;
 290                 goto out;
 291         }
 292
 293         info->chip = chip;
 294         info->map = chip->regmap;
 295         if (!info->map) {
 296                 dev_err(&pdev->dev, "no regmap!\n");
 297                 ret = -EINVAL;
 298                 goto out;
 299         }
 300
 301         info->dev = &pdev->dev;
 302         dev_set_drvdata(&pdev->dev, info);
 303
 304         ret = pm80x_request_irq(chip, info->irq, rtc_update_handler,
 305                                 IRQF_ONESHOT, "rtc", info);
 306         if (ret < 0) {
 307                 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
 308                         info->irq, ret);
 309                 goto out;
 310         }
 311
 312         ret = pm80x_rtc_read_time(&pdev->dev, &tm);
 313         if (ret < 0) {
 314                 dev_err(&pdev->dev, "Failed to read initial time.\n");
 315                 goto out_rtc;
 316         }
 317         if ((tm.tm_year < 70) || (tm.tm_year > 138)) {
 318                 tm.tm_year = 70;
 319                 tm.tm_mon = 0;
 320                 tm.tm_mday = 1;
 321                 tm.tm_hour = 0;
 322                 tm.tm_min = 0;
 323                 tm.tm_sec = 0;
 324                 ret = pm80x_rtc_set_time(&pdev->dev, &tm);
 325                 if (ret < 0) {
 326                         dev_err(&pdev->dev, "Failed to set initial time.\n");
 327                         goto out_rtc;
 328                 }
 329         }
 330         rtc_tm_to_time(&tm, &ticks);
 331
 332         info->rtc_dev = devm_rtc_device_register(&pdev->dev, "88pm80x-rtc",
 333                                             &pm80x_rtc_ops, THIS_MODULE);
 334         if (IS_ERR(info->rtc_dev)) {
 335                 ret = PTR_ERR(info->rtc_dev);
 336                 dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
 337                 goto out_rtc;
 338         }
 339         /*
 340          * enable internal XO instead of internal 3.25MHz clock since it can
 341          * free running in PMIC power-down state.
 342          */
 343         regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_RTC1_USE_XO,
 344                            PM800_RTC1_USE_XO);
 345
 346         /* remember whether this power up is caused by PMIC RTC or not */
 347         info->rtc_dev->dev.platform_data = &pdata->rtc_wakeup;
 348
 349         device_init_wakeup(&pdev->dev, 1);
 350
 351         return 0;
 352 out_rtc:
 353         pm80x_free_irq(chip, info->irq, info);
 354 out:
 355         return ret;
 356 }
 357
 358 static int pm80x_rtc_remove(struct platform_device *pdev)
 359 {
 360         struct pm80x_rtc_info *info = platform_get_drvdata(pdev);
 361         pm80x_free_irq(info->chip, info->irq, info);
 362         return 0;
 363 }
 364
 365 static struct platform_driver pm80x_rtc_driver = {
 366         .driver = {
 367                    .name = "88pm80x-rtc",
 368                    .pm = &pm80x_rtc_pm_ops,
 369                    },
 370         .probe = pm80x_rtc_probe,
 371         .remove = pm80x_rtc_remove,
 372 };
 373
 374 module_platform_driver(pm80x_rtc_driver);
 375
 376 MODULE_LICENSE("GPL");
 377 MODULE_DESCRIPTION("Marvell 88PM80x RTC driver");
 378 MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
 379 MODULE_ALIAS("platform:88pm80x-rtc");