drivers/rtc/rtc-88pm80x.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Real Time Clock driver for Marvell 88PM80x PMIC
   4  *
   5  * Copyright (c) 2012 Marvell International Ltd.
   6  *  Wenzeng Chen<wzch@marvell.com>
   7  *  Qiao Zhou <zhouqiao@marvell.com>
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/slab.h>
  13 #include <linux/regmap.h>
  14 #include <linux/mfd/core.h>
  15 #include <linux/mfd/88pm80x.h>
  16 #include <linux/rtc.h>
  17
  18 #define PM800_RTC_COUNTER1              (0xD1)
  19 #define PM800_RTC_COUNTER2              (0xD2)
  20 #define PM800_RTC_COUNTER3              (0xD3)
  21 #define PM800_RTC_COUNTER4              (0xD4)
  22 #define PM800_RTC_EXPIRE1_1             (0xD5)
  23 #define PM800_RTC_EXPIRE1_2             (0xD6)
  24 #define PM800_RTC_EXPIRE1_3             (0xD7)
  25 #define PM800_RTC_EXPIRE1_4             (0xD8)
  26 #define PM800_RTC_TRIM1                 (0xD9)
  27 #define PM800_RTC_TRIM2                 (0xDA)
  28 #define PM800_RTC_TRIM3                 (0xDB)
  29 #define PM800_RTC_TRIM4                 (0xDC)
  30 #define PM800_RTC_EXPIRE2_1             (0xDD)
  31 #define PM800_RTC_EXPIRE2_2             (0xDE)
  32 #define PM800_RTC_EXPIRE2_3             (0xDF)
  33 #define PM800_RTC_EXPIRE2_4             (0xE0)
  34
  35 #define PM800_POWER_DOWN_LOG1   (0xE5)
  36 #define PM800_POWER_DOWN_LOG2   (0xE6)
  37
  38 struct pm80x_rtc_info {
  39         struct pm80x_chip *chip;
  40         struct regmap *map;
  41         struct rtc_device *rtc_dev;
  42         struct device *dev;
  43
  44         int irq;
  45 };
  46
  47 static irqreturn_t rtc_update_handler(int irq, void *data)
  48 {
  49         struct pm80x_rtc_info *info = (struct pm80x_rtc_info *)data;
  50         int mask;
  51
  52         mask = PM800_ALARM | PM800_ALARM_WAKEUP;
  53         regmap_update_bits(info->map, PM800_RTC_CONTROL, mask | PM800_ALARM1_EN,
  54                            mask);
  55         rtc_update_irq(info->rtc_dev, 1, RTC_AF);
  56         return IRQ_HANDLED;
  57 }
  58
  59 static int pm80x_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
  60 {
  61         struct pm80x_rtc_info *info = dev_get_drvdata(dev);
  62
  63         if (enabled)
  64                 regmap_update_bits(info->map, PM800_RTC_CONTROL,
  65                                    PM800_ALARM1_EN, PM800_ALARM1_EN);
  66         else
  67                 regmap_update_bits(info->map, PM800_RTC_CONTROL,
  68                                    PM800_ALARM1_EN, 0);
  69         return 0;
  70 }
  71
  72 /*
  73  * Calculate the next alarm time given the requested alarm time mask
  74  * and the current time.
  75  */
  76 static void rtc_next_alarm_time(struct rtc_time *next, struct rtc_time *now,
  77                                 struct rtc_time *alrm)
  78 {
  79         unsigned long next_time;
  80         unsigned long now_time;
  81
  82         next->tm_year = now->tm_year;
  83         next->tm_mon = now->tm_mon;
  84         next->tm_mday = now->tm_mday;
  85         next->tm_hour = alrm->tm_hour;
  86         next->tm_min = alrm->tm_min;
  87         next->tm_sec = alrm->tm_sec;
  88
  89         now_time = rtc_tm_to_time64(now);
  90         next_time = rtc_tm_to_time64(next);
  91
  92         if (next_time < now_time) {
  93                 /* Advance one day */
  94                 next_time += 60 * 60 * 24;
  95                 rtc_time64_to_tm(next_time, next);
  96         }
  97 }
  98
  99 static int pm80x_rtc_read_time(struct device *dev, struct rtc_time *tm)
 100 {
 101         struct pm80x_rtc_info *info = dev_get_drvdata(dev);
 102         unsigned char buf[4];
 103         unsigned long ticks, base, data;
 104         regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
 105         base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 106                 (buf[1] << 8) | buf[0];
 107         dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
 108
 109         /* load 32-bit read-only counter */
 110         regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
 111         data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 112                 (buf[1] << 8) | buf[0];
 113         ticks = base + data;
 114         dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
 115                 base, data, ticks);
 116         rtc_time64_to_tm(ticks, tm);
 117         return 0;
 118 }
 119
 120 static int pm80x_rtc_set_time(struct device *dev, struct rtc_time *tm)
 121 {
 122         struct pm80x_rtc_info *info = dev_get_drvdata(dev);
 123         unsigned char buf[4];
 124         unsigned long ticks, base, data;
 125
 126         ticks = rtc_tm_to_time64(tm);
 127
 128         /* load 32-bit read-only counter */
 129         regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
 130         data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 131                 (buf[1] << 8) | buf[0];
 132         base = ticks - data;
 133         dev_dbg(info->dev, "set base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
 134                 base, data, ticks);
 135         buf[0] = base & 0xFF;
 136         buf[1] = (base >> 8) & 0xFF;
 137         buf[2] = (base >> 16) & 0xFF;
 138         buf[3] = (base >> 24) & 0xFF;
 139         regmap_raw_write(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
 140
 141         return 0;
 142 }
 143
 144 static int pm80x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 145 {
 146         struct pm80x_rtc_info *info = dev_get_drvdata(dev);
 147         unsigned char buf[4];
 148         unsigned long ticks, base, data;
 149         int ret;
 150
 151         regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
 152         base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 153                 (buf[1] << 8) | buf[0];
 154         dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
 155
 156         regmap_raw_read(info->map, PM800_RTC_EXPIRE1_1, buf, 4);
 157         data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 158                 (buf[1] << 8) | buf[0];
 159         ticks = base + data;
 160         dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
 161                 base, data, ticks);
 162
 163         rtc_time64_to_tm(ticks, &alrm->time);
 164         regmap_read(info->map, PM800_RTC_CONTROL, &ret);
 165         alrm->enabled = (ret & PM800_ALARM1_EN) ? 1 : 0;
 166         alrm->pending = (ret & (PM800_ALARM | PM800_ALARM_WAKEUP)) ? 1 : 0;
 167         return 0;
 168 }
 169
 170 static int pm80x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 171 {
 172         struct pm80x_rtc_info *info = dev_get_drvdata(dev);
 173         struct rtc_time now_tm, alarm_tm;
 174         unsigned long ticks, base, data;
 175         unsigned char buf[4];
 176         int mask;
 177
 178         regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_ALARM1_EN, 0);
 179
 180         regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
 181         base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 182                 (buf[1] << 8) | buf[0];
 183         dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
 184
 185         /* load 32-bit read-only counter */
 186         regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
 187         data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
 188                 (buf[1] << 8) | buf[0];
 189         ticks = base + data;
 190         dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
 191                 base, data, ticks);
 192
 193         rtc_time64_to_tm(ticks, &now_tm);
 194         dev_dbg(info->dev, "%s, now time : %lu\n", __func__, ticks);
 195         rtc_next_alarm_time(&alarm_tm, &now_tm, &alrm->time);
 196         /* get new ticks for alarm in 24 hours */
 197         ticks = rtc_tm_to_time64(&alarm_tm);
 198         dev_dbg(info->dev, "%s, alarm time: %lu\n", __func__, ticks);
 199         data = ticks - base;
 200
 201         buf[0] = data & 0xff;
 202         buf[1] = (data >> 8) & 0xff;
 203         buf[2] = (data >> 16) & 0xff;
 204         buf[3] = (data >> 24) & 0xff;
 205         regmap_raw_write(info->map, PM800_RTC_EXPIRE1_1, buf, 4);
 206         if (alrm->enabled) {
 207                 mask = PM800_ALARM | PM800_ALARM_WAKEUP | PM800_ALARM1_EN;
 208                 regmap_update_bits(info->map, PM800_RTC_CONTROL, mask, mask);
 209         } else {
 210                 mask = PM800_ALARM | PM800_ALARM_WAKEUP | PM800_ALARM1_EN;
 211                 regmap_update_bits(info->map, PM800_RTC_CONTROL, mask,
 212                                    PM800_ALARM | PM800_ALARM_WAKEUP);
 213         }
 214         return 0;
 215 }
 216
 217 static const struct rtc_class_ops pm80x_rtc_ops = {
 218         .read_time = pm80x_rtc_read_time,
 219         .set_time = pm80x_rtc_set_time,
 220         .read_alarm = pm80x_rtc_read_alarm,
 221         .set_alarm = pm80x_rtc_set_alarm,
 222         .alarm_irq_enable = pm80x_rtc_alarm_irq_enable,
 223 };
 224
 225 #ifdef CONFIG_PM_SLEEP
 226 static int pm80x_rtc_suspend(struct device *dev)
 227 {
 228         return pm80x_dev_suspend(dev);
 229 }
 230
 231 static int pm80x_rtc_resume(struct device *dev)
 232 {
 233         return pm80x_dev_resume(dev);
 234 }
 235 #endif
 236
 237 static SIMPLE_DEV_PM_OPS(pm80x_rtc_pm_ops, pm80x_rtc_suspend, pm80x_rtc_resume);
 238
 239 static int pm80x_rtc_probe(struct platform_device *pdev)
 240 {
 241         struct pm80x_chip *chip = dev_get_drvdata(pdev->dev.parent);
 242         struct pm80x_rtc_pdata *pdata = dev_get_platdata(&pdev->dev);
 243         struct pm80x_rtc_info *info;
 244         struct device_node *node = pdev->dev.of_node;
 245         int ret;
 246
 247         if (!pdata && !node) {
 248                 dev_err(&pdev->dev,
 249                         "pm80x-rtc requires platform data or of_node\n");
 250                 return -EINVAL;
 251         }
 252
 253         if (!pdata) {
 254                 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 255                 if (!pdata) {
 256                         dev_err(&pdev->dev, "failed to allocate memory\n");
 257                         return -ENOMEM;
 258                 }
 259         }
 260
 261         info =
 262             devm_kzalloc(&pdev->dev, sizeof(struct pm80x_rtc_info), GFP_KERNEL);
 263         if (!info)
 264                 return -ENOMEM;
 265         info->irq = platform_get_irq(pdev, 0);
 266         if (info->irq < 0) {
 267                 ret = -EINVAL;
 268                 goto out;
 269         }
 270
 271         info->chip = chip;
 272         info->map = chip->regmap;
 273         if (!info->map) {
 274                 dev_err(&pdev->dev, "no regmap!\n");
 275                 ret = -EINVAL;
 276                 goto out;
 277         }
 278
 279         info->dev = &pdev->dev;
 280         dev_set_drvdata(&pdev->dev, info);
 281
 282         info->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
 283         if (IS_ERR(info->rtc_dev))
 284                 return PTR_ERR(info->rtc_dev);
 285
 286         ret = pm80x_request_irq(chip, info->irq, rtc_update_handler,
 287                                 IRQF_ONESHOT, "rtc", info);
 288         if (ret < 0) {
 289                 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
 290                         info->irq, ret);
 291                 goto out;
 292         }
 293
 294         info->rtc_dev->ops = &pm80x_rtc_ops;
 295         info->rtc_dev->range_max = U32_MAX;
 296
 297         ret = devm_rtc_register_device(info->rtc_dev);
 298         if (ret)
 299                 goto out_rtc;
 300
 301         /*
 302          * enable internal XO instead of internal 3.25MHz clock since it can
 303          * free running in PMIC power-down state.
 304          */
 305         regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_RTC1_USE_XO,
 306                            PM800_RTC1_USE_XO);
 307
 308         /* remember whether this power up is caused by PMIC RTC or not */
 309         info->rtc_dev->dev.platform_data = &pdata->rtc_wakeup;
 310
 311         device_init_wakeup(&pdev->dev, 1);
 312
 313         return 0;
 314 out_rtc:
 315         pm80x_free_irq(chip, info->irq, info);
 316 out:
 317         return ret;
 318 }
 319
 320 static int pm80x_rtc_remove(struct platform_device *pdev)
 321 {
 322         struct pm80x_rtc_info *info = platform_get_drvdata(pdev);
 323         pm80x_free_irq(info->chip, info->irq, info);
 324         return 0;
 325 }
 326
 327 static struct platform_driver pm80x_rtc_driver = {
 328         .driver = {
 329                    .name = "88pm80x-rtc",
 330                    .pm = &pm80x_rtc_pm_ops,
 331                    },
 332         .probe = pm80x_rtc_probe,
 333         .remove = pm80x_rtc_remove,
 334 };
 335
 336 module_platform_driver(pm80x_rtc_driver);
 337
 338 MODULE_LICENSE("GPL");
 339 MODULE_DESCRIPTION("Marvell 88PM80x RTC driver");
 340 MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
 341 MODULE_ALIAS("platform:88pm80x-rtc");