drivers/rtc/rtc-test.c

   1 /*
   2  * An RTC test device/driver
   3  * Copyright (C) 2005 Tower Technologies
   4  * Author: Alessandro Zummo <a.zummo@towertech.it>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/err.h>
  13 #include <linux/rtc.h>
  14 #include <linux/platform_device.h>
  15
  16 #define MAX_RTC_TEST 3
  17
  18 struct rtc_test_data {
  19         struct rtc_device *rtc;
  20         time64_t offset;
  21         struct timer_list alarm;
  22         bool alarm_en;
  23 };
  24
  25 struct platform_device *pdev[MAX_RTC_TEST];
  26
  27 static int test_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
  28 {
  29         struct rtc_test_data *rtd = dev_get_drvdata(dev);
  30         time64_t alarm;
  31
  32         alarm = (rtd->alarm.expires - jiffies) / HZ;
  33         alarm += ktime_get_real_seconds() + rtd->offset;
  34
  35         rtc_time64_to_tm(alarm, &alrm->time);
  36         alrm->enabled = rtd->alarm_en;
  37
  38         return 0;
  39 }
  40
  41 static int test_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
  42 {
  43         struct rtc_test_data *rtd = dev_get_drvdata(dev);
  44         ktime_t timeout;
  45         u64 expires;
  46
  47         timeout = rtc_tm_to_time64(&alrm->time) - ktime_get_real_seconds();
  48         timeout -= rtd->offset;
  49
  50         del_timer(&rtd->alarm);
  51
  52         expires = jiffies + timeout * HZ;
  53         if (expires > U32_MAX)
  54                 expires = U32_MAX;
  55
  56         pr_err("ABE: %s +%d %s\n", __FILE__, __LINE__, __func__);
  57         rtd->alarm.expires = expires;
  58
  59         if (alrm->enabled)
  60                 add_timer(&rtd->alarm);
  61
  62         rtd->alarm_en = alrm->enabled;
  63
  64         return 0;
  65 }
  66
  67 static int test_rtc_read_time(struct device *dev, struct rtc_time *tm)
  68 {
  69         struct rtc_test_data *rtd = dev_get_drvdata(dev);
  70
  71         rtc_time64_to_tm(ktime_get_real_seconds() + rtd->offset, tm);
  72
  73         return 0;
  74 }
  75
  76 static int test_rtc_set_mmss64(struct device *dev, time64_t secs)
  77 {
  78         struct rtc_test_data *rtd = dev_get_drvdata(dev);
  79
  80         rtd->offset = secs - ktime_get_real_seconds();
  81
  82         return 0;
  83 }
  84
  85 static int test_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
  86 {
  87         struct rtc_test_data *rtd = dev_get_drvdata(dev);
  88
  89         rtd->alarm_en = enable;
  90         if (enable)
  91                 add_timer(&rtd->alarm);
  92         else
  93                 del_timer(&rtd->alarm);
  94
  95         return 0;
  96 }
  97
  98 static const struct rtc_class_ops test_rtc_ops_noalm = {
  99         .read_time = test_rtc_read_time,
 100         .set_mmss64 = test_rtc_set_mmss64,
 101         .alarm_irq_enable = test_rtc_alarm_irq_enable,
 102 };
 103
 104 static const struct rtc_class_ops test_rtc_ops = {
 105         .read_time = test_rtc_read_time,
 106         .read_alarm = test_rtc_read_alarm,
 107         .set_alarm = test_rtc_set_alarm,
 108         .set_mmss64 = test_rtc_set_mmss64,
 109         .alarm_irq_enable = test_rtc_alarm_irq_enable,
 110 };
 111
 112 static void test_rtc_alarm_handler(struct timer_list *t)
 113 {
 114         struct rtc_test_data *rtd = from_timer(rtd, t, alarm);
 115
 116         rtc_update_irq(rtd->rtc, 1, RTC_AF | RTC_IRQF);
 117 }
 118
 119 static int test_probe(struct platform_device *plat_dev)
 120 {
 121         struct rtc_test_data *rtd;
 122
 123         rtd = devm_kzalloc(&plat_dev->dev, sizeof(*rtd), GFP_KERNEL);
 124         if (!rtd)
 125                 return -ENOMEM;
 126
 127         platform_set_drvdata(plat_dev, rtd);
 128
 129         rtd->rtc = devm_rtc_allocate_device(&plat_dev->dev);
 130         if (IS_ERR(rtd->rtc))
 131                 return PTR_ERR(rtd->rtc);
 132
 133         switch (plat_dev->id) {
 134         case 0:
 135                 rtd->rtc->ops = &test_rtc_ops_noalm;
 136                 break;
 137         default:
 138                 rtd->rtc->ops = &test_rtc_ops;
 139         }
 140
 141         timer_setup(&rtd->alarm, test_rtc_alarm_handler, 0);
 142         rtd->alarm.expires = 0;
 143
 144         return rtc_register_device(rtd->rtc);
 145 }
 146
 147 static struct platform_driver test_driver = {
 148         .probe  = test_probe,
 149         .driver = {
 150                 .name = "rtc-test",
 151         },
 152 };
 153
 154 static int __init test_init(void)
 155 {
 156         int i, err;
 157
 158         if ((err = platform_driver_register(&test_driver)))
 159                 return err;
 160
 161         err = -ENOMEM;
 162         for (i = 0; i < MAX_RTC_TEST; i++) {
 163                 pdev[i] = platform_device_alloc("rtc-test", i);
 164                 if (!pdev[i])
 165                         goto exit_free_mem;
 166         }
 167
 168         for (i = 0; i < MAX_RTC_TEST; i++) {
 169                 err = platform_device_add(pdev[i]);
 170                 if (err)
 171                         goto exit_device_del;
 172         }
 173
 174         return 0;
 175
 176 exit_device_del:
 177         for (; i > 0; i--)
 178                 platform_device_del(pdev[i - 1]);
 179
 180 exit_free_mem:
 181         for (i = 0; i < MAX_RTC_TEST; i++)
 182                 platform_device_put(pdev[i]);
 183
 184         platform_driver_unregister(&test_driver);
 185         return err;
 186 }
 187
 188 static void __exit test_exit(void)
 189 {
 190         int i;
 191
 192         for (i = 0; i < MAX_RTC_TEST; i++)
 193                 platform_device_unregister(pdev[i]);
 194
 195         platform_driver_unregister(&test_driver);
 196 }
 197
 198 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
 199 MODULE_DESCRIPTION("RTC test driver/device");
 200 MODULE_LICENSE("GPL");
 201
 202 module_init(test_init);
 203 module_exit(test_exit);