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. */
23static struct platform_device *tile_rtc_platform_device;
24
25/*
26 * RTC read routine.  Gets time info from RTC chip via hypervisor syscall.
27 */
28static 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 */
52static 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 */
71static 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 */
79static 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
94static 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 */
104static 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
124exit_device_put:
125	platform_device_put(tile_rtc_platform_device);
126
127exit_driver_unregister:
128	platform_driver_unregister(&tile_rtc_platform_driver);
129	return err;
130}
131
132/*
133 * Driver cleanup routine.
134 */
135static 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
141module_init(tile_rtc_driver_init);
142module_exit(tile_rtc_driver_exit);
143
144MODULE_DESCRIPTION("Tilera-specific Real Time Clock Driver");
145MODULE_LICENSE("GPL");
146MODULE_ALIAS("platform:rtc-tile");
147