Commit | Line | Data |
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defb4514 SB |
1 | /* |
2 | * Driver for the RTC in Marvell SoCs. | |
3 | * | |
4 | * This file is licensed under the terms of the GNU General Public | |
5 | * License version 2. This program is licensed "as is" without any | |
6 | * warranty of any kind, whether express or implied. | |
7 | */ | |
8 | ||
9 | #include <linux/init.h> | |
10 | #include <linux/kernel.h> | |
11 | #include <linux/rtc.h> | |
12 | #include <linux/bcd.h> | |
13 | #include <linux/io.h> | |
14 | #include <linux/platform_device.h> | |
9d1d4f9e | 15 | #include <linux/delay.h> |
defb4514 SB |
16 | |
17 | ||
18 | #define RTC_TIME_REG_OFFS 0 | |
19 | #define RTC_SECONDS_OFFS 0 | |
20 | #define RTC_MINUTES_OFFS 8 | |
21 | #define RTC_HOURS_OFFS 16 | |
22 | #define RTC_WDAY_OFFS 24 | |
23 | #define RTC_HOURS_12H_MODE (1 << 22) /* 12 hours mode */ | |
24 | ||
25 | #define RTC_DATE_REG_OFFS 4 | |
26 | #define RTC_MDAY_OFFS 0 | |
27 | #define RTC_MONTH_OFFS 8 | |
28 | #define RTC_YEAR_OFFS 16 | |
29 | ||
30 | ||
31 | struct rtc_plat_data { | |
32 | struct rtc_device *rtc; | |
33 | void __iomem *ioaddr; | |
34 | }; | |
35 | ||
36 | static int mv_rtc_set_time(struct device *dev, struct rtc_time *tm) | |
37 | { | |
38 | struct rtc_plat_data *pdata = dev_get_drvdata(dev); | |
39 | void __iomem *ioaddr = pdata->ioaddr; | |
40 | u32 rtc_reg; | |
41 | ||
42 | rtc_reg = (bin2bcd(tm->tm_sec) << RTC_SECONDS_OFFS) | | |
43 | (bin2bcd(tm->tm_min) << RTC_MINUTES_OFFS) | | |
44 | (bin2bcd(tm->tm_hour) << RTC_HOURS_OFFS) | | |
45 | (bin2bcd(tm->tm_wday) << RTC_WDAY_OFFS); | |
46 | writel(rtc_reg, ioaddr + RTC_TIME_REG_OFFS); | |
47 | ||
48 | rtc_reg = (bin2bcd(tm->tm_mday) << RTC_MDAY_OFFS) | | |
49 | (bin2bcd(tm->tm_mon + 1) << RTC_MONTH_OFFS) | | |
50 | (bin2bcd(tm->tm_year % 100) << RTC_YEAR_OFFS); | |
51 | writel(rtc_reg, ioaddr + RTC_DATE_REG_OFFS); | |
52 | ||
53 | return 0; | |
54 | } | |
55 | ||
56 | static int mv_rtc_read_time(struct device *dev, struct rtc_time *tm) | |
57 | { | |
58 | struct rtc_plat_data *pdata = dev_get_drvdata(dev); | |
59 | void __iomem *ioaddr = pdata->ioaddr; | |
60 | u32 rtc_time, rtc_date; | |
61 | unsigned int year, month, day, hour, minute, second, wday; | |
62 | ||
63 | rtc_time = readl(ioaddr + RTC_TIME_REG_OFFS); | |
64 | rtc_date = readl(ioaddr + RTC_DATE_REG_OFFS); | |
65 | ||
66 | second = rtc_time & 0x7f; | |
67 | minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f; | |
68 | hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */ | |
69 | wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7; | |
70 | ||
71 | day = rtc_date & 0x3f; | |
72 | month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f; | |
73 | year = (rtc_date >> RTC_YEAR_OFFS) & 0xff; | |
74 | ||
75 | tm->tm_sec = bcd2bin(second); | |
76 | tm->tm_min = bcd2bin(minute); | |
77 | tm->tm_hour = bcd2bin(hour); | |
78 | tm->tm_mday = bcd2bin(day); | |
79 | tm->tm_wday = bcd2bin(wday); | |
80 | tm->tm_mon = bcd2bin(month) - 1; | |
81 | /* hw counts from year 2000, but tm_year is relative to 1900 */ | |
82 | tm->tm_year = bcd2bin(year) + 100; | |
83 | ||
84 | return rtc_valid_tm(tm); | |
85 | } | |
86 | ||
87 | static const struct rtc_class_ops mv_rtc_ops = { | |
88 | .read_time = mv_rtc_read_time, | |
89 | .set_time = mv_rtc_set_time, | |
90 | }; | |
91 | ||
92 | static int __init mv_rtc_probe(struct platform_device *pdev) | |
93 | { | |
94 | struct resource *res; | |
95 | struct rtc_plat_data *pdata; | |
96 | resource_size_t size; | |
97 | u32 rtc_time; | |
98 | ||
99 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
100 | if (!res) | |
101 | return -ENODEV; | |
102 | ||
103 | pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); | |
104 | if (!pdata) | |
105 | return -ENOMEM; | |
106 | ||
107 | size = resource_size(res); | |
108 | if (!devm_request_mem_region(&pdev->dev, res->start, size, | |
109 | pdev->name)) | |
110 | return -EBUSY; | |
111 | ||
112 | pdata->ioaddr = devm_ioremap(&pdev->dev, res->start, size); | |
113 | if (!pdata->ioaddr) | |
114 | return -ENOMEM; | |
115 | ||
116 | /* make sure the 24 hours mode is enabled */ | |
117 | rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS); | |
118 | if (rtc_time & RTC_HOURS_12H_MODE) { | |
119 | dev_err(&pdev->dev, "24 Hours mode not supported.\n"); | |
120 | return -EINVAL; | |
121 | } | |
122 | ||
9d1d4f9e NP |
123 | /* make sure it is actually functional */ |
124 | if (rtc_time == 0x01000000) { | |
125 | ssleep(1); | |
126 | rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS); | |
127 | if (rtc_time == 0x01000000) { | |
128 | dev_err(&pdev->dev, "internal RTC not ticking\n"); | |
129 | return -ENODEV; | |
130 | } | |
131 | } | |
132 | ||
defb4514 SB |
133 | platform_set_drvdata(pdev, pdata); |
134 | pdata->rtc = rtc_device_register(pdev->name, &pdev->dev, | |
135 | &mv_rtc_ops, THIS_MODULE); | |
136 | if (IS_ERR(pdata->rtc)) | |
137 | return PTR_ERR(pdata->rtc); | |
138 | ||
139 | return 0; | |
140 | } | |
141 | ||
142 | static int __exit mv_rtc_remove(struct platform_device *pdev) | |
143 | { | |
144 | struct rtc_plat_data *pdata = platform_get_drvdata(pdev); | |
145 | ||
146 | rtc_device_unregister(pdata->rtc); | |
147 | return 0; | |
148 | } | |
149 | ||
150 | static struct platform_driver mv_rtc_driver = { | |
151 | .remove = __exit_p(mv_rtc_remove), | |
152 | .driver = { | |
153 | .name = "rtc-mv", | |
154 | .owner = THIS_MODULE, | |
155 | }, | |
156 | }; | |
157 | ||
158 | static __init int mv_init(void) | |
159 | { | |
160 | return platform_driver_probe(&mv_rtc_driver, mv_rtc_probe); | |
161 | } | |
162 | ||
163 | static __exit void mv_exit(void) | |
164 | { | |
165 | platform_driver_unregister(&mv_rtc_driver); | |
166 | } | |
167 | ||
168 | module_init(mv_init); | |
169 | module_exit(mv_exit); | |
170 | ||
171 | MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>"); | |
172 | MODULE_DESCRIPTION("Marvell RTC driver"); | |
173 | MODULE_LICENSE("GPL"); | |
174 | MODULE_ALIAS("platform:rtc-mv"); |