drivers/rtc/rtc-pcap.c

   1 /*
   2  *  pcap rtc code for Motorola EZX phones
   3  *
   4  *  Copyright (c) 2008 guiming zhuo <gmzhuo@gmail.com>
   5  *  Copyright (c) 2009 Daniel Ribeiro <drwyrm@gmail.com>
   6  *
   7  *  Based on Motorola's rtc.c Copyright (c) 2003-2005 Motorola
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License version 2 as
  11  *  published by the Free Software Foundation.
  12  *
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/init.h>
  18 #include <linux/mfd/ezx-pcap.h>
  19 #include <linux/rtc.h>
  20 #include <linux/slab.h>
  21 #include <linux/platform_device.h>
  22
  23 struct pcap_rtc {
  24         struct pcap_chip *pcap;
  25         struct rtc_device *rtc;
  26 };
  27
  28 static irqreturn_t pcap_rtc_irq(int irq, void *_pcap_rtc)
  29 {
  30         struct pcap_rtc *pcap_rtc = _pcap_rtc;
  31         unsigned long rtc_events;
  32
  33         if (irq == pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_1HZ))
  34                 rtc_events = RTC_IRQF | RTC_UF;
  35         else if (irq == pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_TODA))
  36                 rtc_events = RTC_IRQF | RTC_AF;
  37         else
  38                 rtc_events = 0;
  39
  40         rtc_update_irq(pcap_rtc->rtc, 1, rtc_events);
  41         return IRQ_HANDLED;
  42 }
  43
  44 static int pcap_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
  45 {
  46         struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
  47         struct rtc_time *tm = &alrm->time;
  48         unsigned long secs;
  49         u32 tod;        /* time of day, seconds since midnight */
  50         u32 days;       /* days since 1/1/1970 */
  51
  52         ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_TODA, &tod);
  53         secs = tod & PCAP_RTC_TOD_MASK;
  54
  55         ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_DAYA, &days);
  56         secs += (days & PCAP_RTC_DAY_MASK) * SEC_PER_DAY;
  57
  58         rtc_time64_to_tm(secs, tm);
  59
  60         return 0;
  61 }
  62
  63 static int pcap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
  64 {
  65         struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
  66         unsigned long secs = rtc_tm_to_time64(&alrm->time);
  67         u32 tod, days;
  68
  69         tod = secs % SEC_PER_DAY;
  70         ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_TODA, tod);
  71
  72         days = secs / SEC_PER_DAY;
  73         ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_DAYA, days);
  74
  75         return 0;
  76 }
  77
  78 static int pcap_rtc_read_time(struct device *dev, struct rtc_time *tm)
  79 {
  80         struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
  81         unsigned long secs;
  82         u32 tod, days;
  83
  84         ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_TOD, &tod);
  85         secs = tod & PCAP_RTC_TOD_MASK;
  86
  87         ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_DAY, &days);
  88         secs += (days & PCAP_RTC_DAY_MASK) * SEC_PER_DAY;
  89
  90         rtc_time64_to_tm(secs, tm);
  91
  92         return 0;
  93 }
  94
  95 static int pcap_rtc_set_time(struct device *dev, struct rtc_time *tm)
  96 {
  97         struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
  98         unsigned long secs = rtc_tm_to_time64(tm);
  99         u32 tod, days;
 100
 101         tod = secs % SEC_PER_DAY;
 102         ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_TOD, tod);
 103
 104         days = secs / SEC_PER_DAY;
 105         ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_DAY, days);
 106
 107         return 0;
 108 }
 109
 110 static int pcap_rtc_irq_enable(struct device *dev, int pirq, unsigned int en)
 111 {
 112         struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
 113
 114         if (en)
 115                 enable_irq(pcap_to_irq(pcap_rtc->pcap, pirq));
 116         else
 117                 disable_irq(pcap_to_irq(pcap_rtc->pcap, pirq));
 118
 119         return 0;
 120 }
 121
 122 static int pcap_rtc_alarm_irq_enable(struct device *dev, unsigned int en)
 123 {
 124         return pcap_rtc_irq_enable(dev, PCAP_IRQ_TODA, en);
 125 }
 126
 127 static const struct rtc_class_ops pcap_rtc_ops = {
 128         .read_time = pcap_rtc_read_time,
 129         .set_time = pcap_rtc_set_time,
 130         .read_alarm = pcap_rtc_read_alarm,
 131         .set_alarm = pcap_rtc_set_alarm,
 132         .alarm_irq_enable = pcap_rtc_alarm_irq_enable,
 133 };
 134
 135 static int __init pcap_rtc_probe(struct platform_device *pdev)
 136 {
 137         struct pcap_rtc *pcap_rtc;
 138         int timer_irq, alarm_irq;
 139         int err = -ENOMEM;
 140
 141         pcap_rtc = devm_kzalloc(&pdev->dev, sizeof(struct pcap_rtc),
 142                                 GFP_KERNEL);
 143         if (!pcap_rtc)
 144                 return err;
 145
 146         pcap_rtc->pcap = dev_get_drvdata(pdev->dev.parent);
 147
 148         platform_set_drvdata(pdev, pcap_rtc);
 149
 150         pcap_rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
 151         if (IS_ERR(pcap_rtc->rtc))
 152                 return PTR_ERR(pcap_rtc->rtc);
 153
 154         pcap_rtc->rtc->ops = &pcap_rtc_ops;
 155         pcap_rtc->rtc->range_max = (1 << 14) * 86400ULL - 1;
 156
 157         timer_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_1HZ);
 158         alarm_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_TODA);
 159
 160         err = devm_request_irq(&pdev->dev, timer_irq, pcap_rtc_irq, 0,
 161                                 "RTC Timer", pcap_rtc);
 162         if (err)
 163                 return err;
 164
 165         err = devm_request_irq(&pdev->dev, alarm_irq, pcap_rtc_irq, 0,
 166                                 "RTC Alarm", pcap_rtc);
 167         if (err)
 168                 return err;
 169
 170         return rtc_register_device(pcap_rtc->rtc);
 171 }
 172
 173 static int __exit pcap_rtc_remove(struct platform_device *pdev)
 174 {
 175         return 0;
 176 }
 177
 178 static struct platform_driver pcap_rtc_driver = {
 179         .remove = __exit_p(pcap_rtc_remove),
 180         .driver = {
 181                 .name  = "pcap-rtc",
 182         },
 183 };
 184
 185 module_platform_driver_probe(pcap_rtc_driver, pcap_rtc_probe);
 186
 187 MODULE_DESCRIPTION("Motorola pcap rtc driver");
 188 MODULE_AUTHOR("guiming zhuo <gmzhuo@gmail.com>");
 189 MODULE_LICENSE("GPL");