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 */
read_rtc_time(struct device * dev,struct rtc_time * tm)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 */
set_rtc_time(struct device * dev,struct rtc_time * tm)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 */
tile_rtc_probe(struct platform_device * dev)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 /*
95 * Device cleanup routine.
96 */
tile_rtc_remove(struct platform_device * dev)97 static int tile_rtc_remove(struct platform_device *dev)
98 {
99 platform_set_drvdata(dev, NULL);
100
101 return 0;
102 }
103
104 static struct platform_driver tile_rtc_platform_driver = {
105 .driver = {
106 .name = "rtc-tile",
107 .owner = THIS_MODULE,
108 },
109 .probe = tile_rtc_probe,
110 .remove = tile_rtc_remove,
111 };
112
113 /*
114 * Driver init routine.
115 */
tile_rtc_driver_init(void)116 static int __init tile_rtc_driver_init(void)
117 {
118 int err;
119
120 err = platform_driver_register(&tile_rtc_platform_driver);
121 if (err)
122 return err;
123
124 tile_rtc_platform_device = platform_device_alloc("rtc-tile", 0);
125 if (tile_rtc_platform_device == NULL) {
126 err = -ENOMEM;
127 goto exit_driver_unregister;
128 }
129
130 err = platform_device_add(tile_rtc_platform_device);
131 if (err)
132 goto exit_device_put;
133
134 return 0;
135
136 exit_device_put:
137 platform_device_put(tile_rtc_platform_device);
138
139 exit_driver_unregister:
140 platform_driver_unregister(&tile_rtc_platform_driver);
141 return err;
142 }
143
144 /*
145 * Driver cleanup routine.
146 */
tile_rtc_driver_exit(void)147 static void __exit tile_rtc_driver_exit(void)
148 {
149 platform_device_unregister(tile_rtc_platform_device);
150 platform_driver_unregister(&tile_rtc_platform_driver);
151 }
152
153 module_init(tile_rtc_driver_init);
154 module_exit(tile_rtc_driver_exit);
155
156 MODULE_DESCRIPTION("Tilera-specific Real Time Clock Driver");
157 MODULE_LICENSE("GPL");
158 MODULE_ALIAS("platform:rtc-tile");
159