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 = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
 120         dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
 121
 122         /* load 32-bit read-only counter */
 123         regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
 124         data = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
 125         ticks = base + data;
 126         dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
 127                 base, data, ticks);
 128         rtc_time_to_tm(ticks, tm);
 129         return 0;
 130 }
 131
 132 static int pm80x_rtc_set_time(struct device *dev, struct rtc_time *tm)
 133 {
 134         struct pm80x_rtc_info *info = dev_get_drvdata(dev);
 135         unsigned char buf[4];
 136         unsigned long ticks, base, data;
 137         if ((tm->tm_year < 70) || (tm->tm_year > 138)) {
 138                 dev_dbg(info->dev,
 139                         "Set time %d out of range. Please set time between 1970 to 2038.\n",
 140                         1900 + tm->tm_year);
 141                 return -EINVAL;
 142         }
 143         rtc_tm_to_time(tm, &ticks);
 144
 145         /* load 32-bit read-only counter */
 146         regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
 147         data = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
 148         base = ticks - data;
 149         dev_dbg(info->dev, "set base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
 150                 base, data, ticks);
 151         buf[0] = base & 0xFF;
 152         buf[1] = (base >> 8) & 0xFF;
 153         buf[2] = (base >> 16) & 0xFF;
 154         buf[3] = (base >> 24) & 0xFF;
 155         regmap_raw_write(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
 156
 157         return 0;
 158 }
 159
 160 static int pm80x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 161 {
 162         struct pm80x_rtc_info *info = dev_get_drvdata(dev);
 163         unsigned char buf[4];
 164         unsigned long ticks, base, data;
 165         int ret;
 166
 167         regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
 168         base = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
 169         dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
 170
 171         regmap_raw_read(info->map, PM800_RTC_EXPIRE1_1, buf, 4);
 172         data = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
 173         ticks = base + data;
 174         dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
 175                 base, data, ticks);
 176
 177         rtc_time_to_tm(ticks, &alrm->time);
 178         regmap_read(info->map, PM800_RTC_CONTROL, &ret);
 179         alrm->enabled = (ret & PM800_ALARM1_EN) ? 1 : 0;
 180         alrm->pending = (ret & (PM800_ALARM | PM800_ALARM_WAKEUP)) ? 1 : 0;
 181         return 0;
 182 }
 183
 184 static int pm80x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 185 {
 186         struct pm80x_rtc_info *info = dev_get_drvdata(dev);
 187         struct rtc_time now_tm, alarm_tm;
 188         unsigned long ticks, base, data;
 189         unsigned char buf[4];
 190         int mask;
 191
 192         regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_ALARM1_EN, 0);
 193
 194         regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
 195         base = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
 196         dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
 197
 198         /* load 32-bit read-only counter */
 199         regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
 200         data = (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0];
 201         ticks = base + data;
 202         dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
 203                 base, data, ticks);
 204
 205         rtc_time_to_tm(ticks, &now_tm);
 206         dev_dbg(info->dev, "%s, now time : %lu\n", __func__, ticks);
 207         rtc_next_alarm_time(&alarm_tm, &now_tm, &alrm->time);
 208         /* get new ticks for alarm in 24 hours */
 209         rtc_tm_to_time(&alarm_tm, &ticks);
 210         dev_dbg(info->dev, "%s, alarm time: %lu\n", __func__, ticks);
 211         data = ticks - base;
 212
 213         buf[0] = data & 0xff;
 214         buf[1] = (data >> 8) & 0xff;
 215         buf[2] = (data >> 16) & 0xff;
 216         buf[3] = (data >> 24) & 0xff;
 217         regmap_raw_write(info->map, PM800_RTC_EXPIRE1_1, buf, 4);
 218         if (alrm->enabled) {
 219                 mask = PM800_ALARM | PM800_ALARM_WAKEUP | PM800_ALARM1_EN;
 220                 regmap_update_bits(info->map, PM800_RTC_CONTROL, mask, mask);
 221         } else {
 222                 mask = PM800_ALARM | PM800_ALARM_WAKEUP | PM800_ALARM1_EN;
 223                 regmap_update_bits(info->map, PM800_RTC_CONTROL, mask,
 224                                    PM800_ALARM | PM800_ALARM_WAKEUP);
 225         }
 226         return 0;
 227 }
 228
 229 static const struct rtc_class_ops pm80x_rtc_ops = {
 230         .read_time = pm80x_rtc_read_time,
 231         .set_time = pm80x_rtc_set_time,
 232         .read_alarm = pm80x_rtc_read_alarm,
 233         .set_alarm = pm80x_rtc_set_alarm,
 234         .alarm_irq_enable = pm80x_rtc_alarm_irq_enable,
 235 };
 236
 237 #ifdef CONFIG_PM_SLEEP
 238 static int pm80x_rtc_suspend(struct device *dev)
 239 {
 240         return pm80x_dev_suspend(dev);
 241 }
 242
 243 static int pm80x_rtc_resume(struct device *dev)
 244 {
 245         return pm80x_dev_resume(dev);
 246 }
 247 #endif
 248
 249 static SIMPLE_DEV_PM_OPS(pm80x_rtc_pm_ops, pm80x_rtc_suspend, pm80x_rtc_resume);
 250
 251 static int pm80x_rtc_probe(struct platform_device *pdev)
 252 {
 253         struct pm80x_chip *chip = dev_get_drvdata(pdev->dev.parent);
 254         struct pm80x_rtc_pdata *pdata = dev_get_platdata(&pdev->dev);
 255         struct pm80x_rtc_info *info;
 256         struct device_node *node = pdev->dev.of_node;
 257         struct rtc_time tm;
 258         unsigned long ticks = 0;
 259         int ret;
 260
 261         if (!pdata && !node) {
 262                 dev_err(&pdev->dev,
 263                         "pm80x-rtc requires platform data or of_node\n");
 264                 return -EINVAL;
 265         }
 266
 267         if (!pdata) {
 268                 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 269                 if (!pdata) {
 270                         dev_err(&pdev->dev, "failed to allocate memory\n");
 271                         return -ENOMEM;
 272                 }
 273         }
 274
 275         info =
 276             devm_kzalloc(&pdev->dev, sizeof(struct pm80x_rtc_info), GFP_KERNEL);
 277         if (!info)
 278                 return -ENOMEM;
 279         info->irq = platform_get_irq(pdev, 0);
 280         if (info->irq < 0) {
 281                 dev_err(&pdev->dev, "No IRQ resource!\n");
 282                 ret = -EINVAL;
 283                 goto out;
 284         }
 285
 286         info->chip = chip;
 287         info->map = chip->regmap;
 288         if (!info->map) {
 289                 dev_err(&pdev->dev, "no regmap!\n");
 290                 ret = -EINVAL;
 291                 goto out;
 292         }
 293
 294         info->dev = &pdev->dev;
 295         dev_set_drvdata(&pdev->dev, info);
 296
 297         ret = pm80x_request_irq(chip, info->irq, rtc_update_handler,
 298                                 IRQF_ONESHOT, "rtc", info);
 299         if (ret < 0) {
 300                 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
 301                         info->irq, ret);
 302                 goto out;
 303         }
 304
 305         ret = pm80x_rtc_read_time(&pdev->dev, &tm);
 306         if (ret < 0) {
 307                 dev_err(&pdev->dev, "Failed to read initial time.\n");
 308                 goto out_rtc;
 309         }
 310         if ((tm.tm_year < 70) || (tm.tm_year > 138)) {
 311                 tm.tm_year = 70;
 312                 tm.tm_mon = 0;
 313                 tm.tm_mday = 1;
 314                 tm.tm_hour = 0;
 315                 tm.tm_min = 0;
 316                 tm.tm_sec = 0;
 317                 ret = pm80x_rtc_set_time(&pdev->dev, &tm);
 318                 if (ret < 0) {
 319                         dev_err(&pdev->dev, "Failed to set initial time.\n");
 320                         goto out_rtc;
 321                 }
 322         }
 323         rtc_tm_to_time(&tm, &ticks);
 324
 325         info->rtc_dev = devm_rtc_device_register(&pdev->dev, "88pm80x-rtc",
 326                                             &pm80x_rtc_ops, THIS_MODULE);
 327         if (IS_ERR(info->rtc_dev)) {
 328                 ret = PTR_ERR(info->rtc_dev);
 329                 dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
 330                 goto out_rtc;
 331         }
 332         /*
 333          * enable internal XO instead of internal 3.25MHz clock since it can
 334          * free running in PMIC power-down state.
 335          */
 336         regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_RTC1_USE_XO,
 337                            PM800_RTC1_USE_XO);
 338
 339         /* remember whether this power up is caused by PMIC RTC or not */
 340         info->rtc_dev->dev.platform_data = &pdata->rtc_wakeup;
 341
 342         device_init_wakeup(&pdev->dev, 1);
 343
 344         return 0;
 345 out_rtc:
 346         pm80x_free_irq(chip, info->irq, info);
 347 out:
 348         return ret;
 349 }
 350
 351 static int pm80x_rtc_remove(struct platform_device *pdev)
 352 {
 353         struct pm80x_rtc_info *info = platform_get_drvdata(pdev);
 354         pm80x_free_irq(info->chip, info->irq, info);
 355         return 0;
 356 }
 357
 358 static struct platform_driver pm80x_rtc_driver = {
 359         .driver = {
 360                    .name = "88pm80x-rtc",
 361                    .pm = &pm80x_rtc_pm_ops,
 362                    },
 363         .probe = pm80x_rtc_probe,
 364         .remove = pm80x_rtc_remove,
 365 };
 366
 367 module_platform_driver(pm80x_rtc_driver);
 368
 369 MODULE_LICENSE("GPL");
 370 MODULE_DESCRIPTION("Marvell 88PM80x RTC driver");
 371 MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
 372 MODULE_ALIAS("platform:88pm80x-rtc");