drivers/rtc/rtc-pcf50633.c

   1 /* NXP PCF50633 RTC Driver
   2  *
   3  * (C) 2006-2008 by Openmoko, Inc.
   4  * Author: Balaji Rao <balajirrao@openmoko.org>
   5  * All rights reserved.
   6  *
   7  * Broken down from monstrous PCF50633 driver mainly by
   8  * Harald Welte, Andy Green and Werner Almesberger
   9  *
  10  *  This program is free software; you can redistribute  it and/or modify it
  11  *  under  the terms of  the GNU General  Public License as published by the
  12  *  Free Software Foundation;  either version 2 of the  License, or (at your
  13  *  option) any later version.
  14  *
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/init.h>
  20 #include <linux/device.h>
  21 #include <linux/slab.h>
  22 #include <linux/platform_device.h>
  23 #include <linux/rtc.h>
  24 #include <linux/bcd.h>
  25 #include <linux/err.h>
  26
  27 #include <linux/mfd/pcf50633/core.h>
  28
  29 #define PCF50633_REG_RTCSC      0x59 /* Second */
  30 #define PCF50633_REG_RTCMN      0x5a /* Minute */
  31 #define PCF50633_REG_RTCHR      0x5b /* Hour */
  32 #define PCF50633_REG_RTCWD      0x5c /* Weekday */
  33 #define PCF50633_REG_RTCDT      0x5d /* Day */
  34 #define PCF50633_REG_RTCMT      0x5e /* Month */
  35 #define PCF50633_REG_RTCYR      0x5f /* Year */
  36 #define PCF50633_REG_RTCSCA     0x60 /* Alarm Second */
  37 #define PCF50633_REG_RTCMNA     0x61 /* Alarm Minute */
  38 #define PCF50633_REG_RTCHRA     0x62 /* Alarm Hour */
  39 #define PCF50633_REG_RTCWDA     0x63 /* Alarm Weekday */
  40 #define PCF50633_REG_RTCDTA     0x64 /* Alarm Day */
  41 #define PCF50633_REG_RTCMTA     0x65 /* Alarm Month */
  42 #define PCF50633_REG_RTCYRA     0x66 /* Alarm Year */
  43
  44 enum pcf50633_time_indexes {
  45         PCF50633_TI_SEC,
  46         PCF50633_TI_MIN,
  47         PCF50633_TI_HOUR,
  48         PCF50633_TI_WKDAY,
  49         PCF50633_TI_DAY,
  50         PCF50633_TI_MONTH,
  51         PCF50633_TI_YEAR,
  52         PCF50633_TI_EXTENT /* always last */
  53 };
  54
  55 struct pcf50633_time {
  56         u_int8_t time[PCF50633_TI_EXTENT];
  57 };
  58
  59 struct pcf50633_rtc {
  60         int alarm_enabled;
  61         int alarm_pending;
  62
  63         struct pcf50633 *pcf;
  64         struct rtc_device *rtc_dev;
  65 };
  66
  67 static void pcf2rtc_time(struct rtc_time *rtc, struct pcf50633_time *pcf)
  68 {
  69         rtc->tm_sec = bcd2bin(pcf->time[PCF50633_TI_SEC]);
  70         rtc->tm_min = bcd2bin(pcf->time[PCF50633_TI_MIN]);
  71         rtc->tm_hour = bcd2bin(pcf->time[PCF50633_TI_HOUR]);
  72         rtc->tm_wday = bcd2bin(pcf->time[PCF50633_TI_WKDAY]);
  73         rtc->tm_mday = bcd2bin(pcf->time[PCF50633_TI_DAY]);
  74         rtc->tm_mon = bcd2bin(pcf->time[PCF50633_TI_MONTH]) - 1;
  75         rtc->tm_year = bcd2bin(pcf->time[PCF50633_TI_YEAR]) + 100;
  76 }
  77
  78 static void rtc2pcf_time(struct pcf50633_time *pcf, struct rtc_time *rtc)
  79 {
  80         pcf->time[PCF50633_TI_SEC] = bin2bcd(rtc->tm_sec);
  81         pcf->time[PCF50633_TI_MIN] = bin2bcd(rtc->tm_min);
  82         pcf->time[PCF50633_TI_HOUR] = bin2bcd(rtc->tm_hour);
  83         pcf->time[PCF50633_TI_WKDAY] = bin2bcd(rtc->tm_wday);
  84         pcf->time[PCF50633_TI_DAY] = bin2bcd(rtc->tm_mday);
  85         pcf->time[PCF50633_TI_MONTH] = bin2bcd(rtc->tm_mon + 1);
  86         pcf->time[PCF50633_TI_YEAR] = bin2bcd(rtc->tm_year % 100);
  87 }
  88
  89 static int
  90 pcf50633_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
  91 {
  92         struct pcf50633_rtc *rtc = dev_get_drvdata(dev);
  93         int err;
  94
  95         if (enabled)
  96                 err = pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
  97         else
  98                 err = pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
  99
 100         if (err < 0)
 101                 return err;
 102
 103         rtc->alarm_enabled = enabled;
 104
 105         return 0;
 106 }
 107
 108 static int pcf50633_rtc_read_time(struct device *dev, struct rtc_time *tm)
 109 {
 110         struct pcf50633_rtc *rtc;
 111         struct pcf50633_time pcf_tm;
 112         int ret;
 113
 114         rtc = dev_get_drvdata(dev);
 115
 116         ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSC,
 117                                             PCF50633_TI_EXTENT,
 118                                             &pcf_tm.time[0]);
 119         if (ret != PCF50633_TI_EXTENT) {
 120                 dev_err(dev, "Failed to read time\n");
 121                 return -EIO;
 122         }
 123
 124         dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
 125                 pcf_tm.time[PCF50633_TI_DAY],
 126                 pcf_tm.time[PCF50633_TI_MONTH],
 127                 pcf_tm.time[PCF50633_TI_YEAR],
 128                 pcf_tm.time[PCF50633_TI_HOUR],
 129                 pcf_tm.time[PCF50633_TI_MIN],
 130                 pcf_tm.time[PCF50633_TI_SEC]);
 131
 132         pcf2rtc_time(tm, &pcf_tm);
 133
 134         dev_dbg(dev, "RTC_TIME: %ptRr\n", tm);
 135
 136         return 0;
 137 }
 138
 139 static int pcf50633_rtc_set_time(struct device *dev, struct rtc_time *tm)
 140 {
 141         struct pcf50633_rtc *rtc;
 142         struct pcf50633_time pcf_tm;
 143         int alarm_masked, ret = 0;
 144
 145         rtc = dev_get_drvdata(dev);
 146
 147         dev_dbg(dev, "RTC_TIME: %ptRr\n", tm);
 148
 149         rtc2pcf_time(&pcf_tm, tm);
 150
 151         dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
 152                 pcf_tm.time[PCF50633_TI_DAY],
 153                 pcf_tm.time[PCF50633_TI_MONTH],
 154                 pcf_tm.time[PCF50633_TI_YEAR],
 155                 pcf_tm.time[PCF50633_TI_HOUR],
 156                 pcf_tm.time[PCF50633_TI_MIN],
 157                 pcf_tm.time[PCF50633_TI_SEC]);
 158
 159
 160         alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);
 161
 162         if (!alarm_masked)
 163                 pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
 164
 165         /* Returns 0 on success */
 166         ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSC,
 167                                              PCF50633_TI_EXTENT,
 168                                              &pcf_tm.time[0]);
 169
 170         if (!alarm_masked)
 171                 pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
 172
 173         return ret;
 174 }
 175
 176 static int pcf50633_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 177 {
 178         struct pcf50633_rtc *rtc;
 179         struct pcf50633_time pcf_tm;
 180         int ret = 0;
 181
 182         rtc = dev_get_drvdata(dev);
 183
 184         alrm->enabled = rtc->alarm_enabled;
 185         alrm->pending = rtc->alarm_pending;
 186
 187         ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSCA,
 188                                 PCF50633_TI_EXTENT, &pcf_tm.time[0]);
 189         if (ret != PCF50633_TI_EXTENT) {
 190                 dev_err(dev, "Failed to read time\n");
 191                 return -EIO;
 192         }
 193
 194         pcf2rtc_time(&alrm->time, &pcf_tm);
 195
 196         return rtc_valid_tm(&alrm->time);
 197 }
 198
 199 static int pcf50633_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 200 {
 201         struct pcf50633_rtc *rtc;
 202         struct pcf50633_time pcf_tm;
 203         int alarm_masked, ret = 0;
 204
 205         rtc = dev_get_drvdata(dev);
 206
 207         rtc2pcf_time(&pcf_tm, &alrm->time);
 208
 209         /* do like mktime does and ignore tm_wday */
 210         pcf_tm.time[PCF50633_TI_WKDAY] = 7;
 211
 212         alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);
 213
 214         /* disable alarm interrupt */
 215         if (!alarm_masked)
 216                 pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
 217
 218         /* Returns 0 on success */
 219         ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSCA,
 220                                 PCF50633_TI_EXTENT, &pcf_tm.time[0]);
 221         if (!alrm->enabled)
 222                 rtc->alarm_pending = 0;
 223
 224         if (!alarm_masked || alrm->enabled)
 225                 pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
 226         rtc->alarm_enabled = alrm->enabled;
 227
 228         return ret;
 229 }
 230
 231 static const struct rtc_class_ops pcf50633_rtc_ops = {
 232         .read_time              = pcf50633_rtc_read_time,
 233         .set_time               = pcf50633_rtc_set_time,
 234         .read_alarm             = pcf50633_rtc_read_alarm,
 235         .set_alarm              = pcf50633_rtc_set_alarm,
 236         .alarm_irq_enable       = pcf50633_rtc_alarm_irq_enable,
 237 };
 238
 239 static void pcf50633_rtc_irq(int irq, void *data)
 240 {
 241         struct pcf50633_rtc *rtc = data;
 242
 243         rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
 244         rtc->alarm_pending = 1;
 245 }
 246
 247 static int pcf50633_rtc_probe(struct platform_device *pdev)
 248 {
 249         struct pcf50633_rtc *rtc;
 250
 251         rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
 252         if (!rtc)
 253                 return -ENOMEM;
 254
 255         rtc->pcf = dev_to_pcf50633(pdev->dev.parent);
 256         platform_set_drvdata(pdev, rtc);
 257         rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, "pcf50633-rtc",
 258                                 &pcf50633_rtc_ops, THIS_MODULE);
 259
 260         if (IS_ERR(rtc->rtc_dev))
 261                 return PTR_ERR(rtc->rtc_dev);
 262
 263         pcf50633_register_irq(rtc->pcf, PCF50633_IRQ_ALARM,
 264                                         pcf50633_rtc_irq, rtc);
 265         return 0;
 266 }
 267
 268 static int pcf50633_rtc_remove(struct platform_device *pdev)
 269 {
 270         struct pcf50633_rtc *rtc;
 271
 272         rtc = platform_get_drvdata(pdev);
 273         pcf50633_free_irq(rtc->pcf, PCF50633_IRQ_ALARM);
 274
 275         return 0;
 276 }
 277
 278 static struct platform_driver pcf50633_rtc_driver = {
 279         .driver = {
 280                 .name = "pcf50633-rtc",
 281         },
 282         .probe = pcf50633_rtc_probe,
 283         .remove = pcf50633_rtc_remove,
 284 };
 285
 286 module_platform_driver(pcf50633_rtc_driver);
 287
 288 MODULE_DESCRIPTION("PCF50633 RTC driver");
 289 MODULE_AUTHOR("Balaji Rao <balajirrao@openmoko.org>");
 290 MODULE_LICENSE("GPL");
 291