kernel/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 platform_device *pdev = to_platform_device(dev);
  47         struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
  48         struct rtc_time *tm = &alrm->time;
  49         unsigned long secs;
  50         u32 tod;        /* time of day, seconds since midnight */
  51         u32 days;       /* days since 1/1/1970 */
  52
  53         ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_TODA, &tod);
  54         secs = tod & PCAP_RTC_TOD_MASK;
  55
  56         ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_DAYA, &days);
  57         secs += (days & PCAP_RTC_DAY_MASK) * SEC_PER_DAY;
  58
  59         rtc_time_to_tm(secs, tm);
  60
  61         return 0;
  62 }
  63
  64 static int pcap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
  65 {
  66         struct platform_device *pdev = to_platform_device(dev);
  67         struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
  68         struct rtc_time *tm = &alrm->time;
  69         unsigned long secs;
  70         u32 tod, days;
  71
  72         rtc_tm_to_time(tm, &secs);
  73
  74         tod = secs % SEC_PER_DAY;
  75         ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_TODA, tod);
  76
  77         days = secs / SEC_PER_DAY;
  78         ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_DAYA, days);
  79
  80         return 0;
  81 }
  82
  83 static int pcap_rtc_read_time(struct device *dev, struct rtc_time *tm)
  84 {
  85         struct platform_device *pdev = to_platform_device(dev);
  86         struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
  87         unsigned long secs;
  88         u32 tod, days;
  89
  90         ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_TOD, &tod);
  91         secs = tod & PCAP_RTC_TOD_MASK;
  92
  93         ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_DAY, &days);
  94         secs += (days & PCAP_RTC_DAY_MASK) * SEC_PER_DAY;
  95
  96         rtc_time_to_tm(secs, tm);
  97
  98         return rtc_valid_tm(tm);
  99 }
 100
 101 static int pcap_rtc_set_mmss(struct device *dev, unsigned long secs)
 102 {
 103         struct platform_device *pdev = to_platform_device(dev);
 104         struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
 105         u32 tod, days;
 106
 107         tod = secs % SEC_PER_DAY;
 108         ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_TOD, tod);
 109
 110         days = secs / SEC_PER_DAY;
 111         ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_DAY, days);
 112
 113         return 0;
 114 }
 115
 116 static int pcap_rtc_irq_enable(struct device *dev, int pirq, unsigned int en)
 117 {
 118         struct platform_device *pdev = to_platform_device(dev);
 119         struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
 120
 121         if (en)
 122                 enable_irq(pcap_to_irq(pcap_rtc->pcap, pirq));
 123         else
 124                 disable_irq(pcap_to_irq(pcap_rtc->pcap, pirq));
 125
 126         return 0;
 127 }
 128
 129 static int pcap_rtc_alarm_irq_enable(struct device *dev, unsigned int en)
 130 {
 131         return pcap_rtc_irq_enable(dev, PCAP_IRQ_TODA, en);
 132 }
 133
 134 static const struct rtc_class_ops pcap_rtc_ops = {
 135         .read_time = pcap_rtc_read_time,
 136         .read_alarm = pcap_rtc_read_alarm,
 137         .set_alarm = pcap_rtc_set_alarm,
 138         .set_mmss = pcap_rtc_set_mmss,
 139         .alarm_irq_enable = pcap_rtc_alarm_irq_enable,
 140 };
 141
 142 static int __init pcap_rtc_probe(struct platform_device *pdev)
 143 {
 144         struct pcap_rtc *pcap_rtc;
 145         int timer_irq, alarm_irq;
 146         int err = -ENOMEM;
 147
 148         pcap_rtc = devm_kzalloc(&pdev->dev, sizeof(struct pcap_rtc),
 149                                 GFP_KERNEL);
 150         if (!pcap_rtc)
 151                 return err;
 152
 153         pcap_rtc->pcap = dev_get_drvdata(pdev->dev.parent);
 154
 155         platform_set_drvdata(pdev, pcap_rtc);
 156
 157         pcap_rtc->rtc = devm_rtc_device_register(&pdev->dev, "pcap",
 158                                         &pcap_rtc_ops, THIS_MODULE);
 159         if (IS_ERR(pcap_rtc->rtc))
 160                 return PTR_ERR(pcap_rtc->rtc);
 161
 162         timer_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_1HZ);
 163         alarm_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_TODA);
 164
 165         err = devm_request_irq(&pdev->dev, timer_irq, pcap_rtc_irq, 0,
 166                                 "RTC Timer", pcap_rtc);
 167         if (err)
 168                 return err;
 169
 170         err = devm_request_irq(&pdev->dev, alarm_irq, pcap_rtc_irq, 0,
 171                                 "RTC Alarm", pcap_rtc);
 172         if (err)
 173                 return err;
 174
 175         return 0;
 176 }
 177
 178 static int __exit pcap_rtc_remove(struct platform_device *pdev)
 179 {
 180         return 0;
 181 }
 182
 183 static struct platform_driver pcap_rtc_driver = {
 184         .remove = __exit_p(pcap_rtc_remove),
 185         .driver = {
 186                 .name  = "pcap-rtc",
 187         },
 188 };
 189
 190 module_platform_driver_probe(pcap_rtc_driver, pcap_rtc_probe);
 191
 192 MODULE_DESCRIPTION("Motorola pcap rtc driver");
 193 MODULE_AUTHOR("guiming zhuo <gmzhuo@gmail.com>");
 194 MODULE_LICENSE("GPL");