GNU Linux-libre 4.4.289-gnu1
[releases.git] / drivers / rtc / rtc-tile.c
1 /*
2  * Copyright 2011 Tilera Corporation. All Rights Reserved.
3  *
4  *   This program is free software; you can redistribute it and/or
5  *   modify it under the terms of the GNU General Public License
6  *   as published by the Free Software Foundation, version 2.
7  *
8  *   This program is distributed in the hope that it will be useful, but
9  *   WITHOUT ANY WARRANTY; without even the implied warranty of
10  *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11  *   NON INFRINGEMENT.  See the GNU General Public License for
12  *   more details.
13  *
14  * Tilera-specific RTC driver.
15  */
16
17 #include <linux/module.h>
18 #include <linux/device.h>
19 #include <linux/rtc.h>
20 #include <linux/platform_device.h>
21
22 /* Platform device pointer. */
23 static struct platform_device *tile_rtc_platform_device;
24
25 /*
26  * RTC read routine.  Gets time info from RTC chip via hypervisor syscall.
27  */
28 static int read_rtc_time(struct device *dev, struct rtc_time *tm)
29 {
30         HV_RTCTime hvtm = hv_get_rtc();
31
32         tm->tm_sec = hvtm.tm_sec;
33         tm->tm_min = hvtm.tm_min;
34         tm->tm_hour = hvtm.tm_hour;
35         tm->tm_mday = hvtm.tm_mday;
36         tm->tm_mon = hvtm.tm_mon;
37         tm->tm_year = hvtm.tm_year;
38         tm->tm_wday = 0;
39         tm->tm_yday = 0;
40         tm->tm_isdst = 0;
41
42         if (rtc_valid_tm(tm) < 0)
43                 dev_warn(dev, "Read invalid date/time from RTC\n");
44
45         return 0;
46 }
47
48 /*
49  * RTC write routine.  Sends time info to hypervisor via syscall, to be
50  * written to RTC chip.
51  */
52 static int set_rtc_time(struct device *dev, struct rtc_time *tm)
53 {
54         HV_RTCTime hvtm;
55
56         hvtm.tm_sec = tm->tm_sec;
57         hvtm.tm_min = tm->tm_min;
58         hvtm.tm_hour = tm->tm_hour;
59         hvtm.tm_mday = tm->tm_mday;
60         hvtm.tm_mon = tm->tm_mon;
61         hvtm.tm_year = tm->tm_year;
62
63         hv_set_rtc(hvtm);
64
65         return 0;
66 }
67
68 /*
69  * RTC read/write ops.
70  */
71 static const struct rtc_class_ops tile_rtc_ops = {
72         .read_time      = read_rtc_time,
73         .set_time       = set_rtc_time,
74 };
75
76 /*
77  * Device probe routine.
78  */
79 static int tile_rtc_probe(struct platform_device *dev)
80 {
81         struct rtc_device *rtc;
82
83         rtc = devm_rtc_device_register(&dev->dev, "tile",
84                                 &tile_rtc_ops, THIS_MODULE);
85
86         if (IS_ERR(rtc))
87                 return PTR_ERR(rtc);
88
89         platform_set_drvdata(dev, rtc);
90
91         return 0;
92 }
93
94 static struct platform_driver tile_rtc_platform_driver = {
95         .driver         = {
96                 .name   = "rtc-tile",
97         },
98         .probe          = tile_rtc_probe,
99 };
100
101 /*
102  * Driver init routine.
103  */
104 static int __init tile_rtc_driver_init(void)
105 {
106         int err;
107
108         err = platform_driver_register(&tile_rtc_platform_driver);
109         if (err)
110                 return err;
111
112         tile_rtc_platform_device = platform_device_alloc("rtc-tile", 0);
113         if (tile_rtc_platform_device == NULL) {
114                 err = -ENOMEM;
115                 goto exit_driver_unregister;
116         }
117
118         err = platform_device_add(tile_rtc_platform_device);
119         if (err)
120                 goto exit_device_put;
121
122         return 0;
123
124 exit_device_put:
125         platform_device_put(tile_rtc_platform_device);
126
127 exit_driver_unregister:
128         platform_driver_unregister(&tile_rtc_platform_driver);
129         return err;
130 }
131
132 /*
133  * Driver cleanup routine.
134  */
135 static void __exit tile_rtc_driver_exit(void)
136 {
137         platform_device_unregister(tile_rtc_platform_device);
138         platform_driver_unregister(&tile_rtc_platform_driver);
139 }
140
141 module_init(tile_rtc_driver_init);
142 module_exit(tile_rtc_driver_exit);
143
144 MODULE_DESCRIPTION("Tilera-specific Real Time Clock Driver");
145 MODULE_LICENSE("GPL");
146 MODULE_ALIAS("platform:rtc-tile");