Commit | Line | Data |
---|---|---|
5ec3e4b7 AN |
1 | /* |
2 | * An rtc driver for the Dallas DS1742 | |
3 | * | |
4 | * Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp> | |
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. | |
f9231a0c TER |
9 | * |
10 | * Copyright (C) 2006 Torsten Ertbjerg Rasmussen <tr@newtec.dk> | |
11 | * - nvram size determined from resource | |
12 | * - this ds1742 driver now supports ds1743. | |
5ec3e4b7 AN |
13 | */ |
14 | ||
15 | #include <linux/bcd.h> | |
16 | #include <linux/init.h> | |
17 | #include <linux/kernel.h> | |
18 | #include <linux/delay.h> | |
19 | #include <linux/jiffies.h> | |
20 | #include <linux/rtc.h> | |
21 | #include <linux/platform_device.h> | |
22 | #include <linux/io.h> | |
23 | ||
f9231a0c | 24 | #define DRV_VERSION "0.3" |
5ec3e4b7 | 25 | |
f9231a0c | 26 | #define RTC_SIZE 8 |
5ec3e4b7 | 27 | |
f9231a0c TER |
28 | #define RTC_CONTROL 0 |
29 | #define RTC_CENTURY 0 | |
30 | #define RTC_SECONDS 1 | |
31 | #define RTC_MINUTES 2 | |
32 | #define RTC_HOURS 3 | |
33 | #define RTC_DAY 4 | |
34 | #define RTC_DATE 5 | |
35 | #define RTC_MONTH 6 | |
36 | #define RTC_YEAR 7 | |
5ec3e4b7 AN |
37 | |
38 | #define RTC_CENTURY_MASK 0x3f | |
39 | #define RTC_SECONDS_MASK 0x7f | |
40 | #define RTC_DAY_MASK 0x07 | |
41 | ||
42 | /* Bits in the Control/Century register */ | |
43 | #define RTC_WRITE 0x80 | |
44 | #define RTC_READ 0x40 | |
45 | ||
46 | /* Bits in the Seconds register */ | |
47 | #define RTC_STOP 0x80 | |
48 | ||
49 | /* Bits in the Day register */ | |
50 | #define RTC_BATT_FLAG 0x80 | |
51 | ||
52 | struct rtc_plat_data { | |
53 | struct rtc_device *rtc; | |
f9231a0c TER |
54 | void __iomem *ioaddr_nvram; |
55 | void __iomem *ioaddr_rtc; | |
56 | size_t size_nvram; | |
57 | size_t size; | |
2e3e31c0 | 58 | resource_size_t baseaddr; |
5ec3e4b7 | 59 | unsigned long last_jiffies; |
3a729700 | 60 | struct bin_attribute nvram_attr; |
5ec3e4b7 AN |
61 | }; |
62 | ||
63 | static int ds1742_rtc_set_time(struct device *dev, struct rtc_time *tm) | |
64 | { | |
65 | struct platform_device *pdev = to_platform_device(dev); | |
66 | struct rtc_plat_data *pdata = platform_get_drvdata(pdev); | |
f9231a0c | 67 | void __iomem *ioaddr = pdata->ioaddr_rtc; |
5ec3e4b7 AN |
68 | u8 century; |
69 | ||
fe20ba70 | 70 | century = bin2bcd((tm->tm_year + 1900) / 100); |
5ec3e4b7 AN |
71 | |
72 | writeb(RTC_WRITE, ioaddr + RTC_CONTROL); | |
73 | ||
fe20ba70 AB |
74 | writeb(bin2bcd(tm->tm_year % 100), ioaddr + RTC_YEAR); |
75 | writeb(bin2bcd(tm->tm_mon + 1), ioaddr + RTC_MONTH); | |
76 | writeb(bin2bcd(tm->tm_wday) & RTC_DAY_MASK, ioaddr + RTC_DAY); | |
77 | writeb(bin2bcd(tm->tm_mday), ioaddr + RTC_DATE); | |
78 | writeb(bin2bcd(tm->tm_hour), ioaddr + RTC_HOURS); | |
79 | writeb(bin2bcd(tm->tm_min), ioaddr + RTC_MINUTES); | |
80 | writeb(bin2bcd(tm->tm_sec) & RTC_SECONDS_MASK, ioaddr + RTC_SECONDS); | |
5ec3e4b7 AN |
81 | |
82 | /* RTC_CENTURY and RTC_CONTROL share same register */ | |
83 | writeb(RTC_WRITE | (century & RTC_CENTURY_MASK), ioaddr + RTC_CENTURY); | |
84 | writeb(century & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL); | |
85 | return 0; | |
86 | } | |
87 | ||
88 | static int ds1742_rtc_read_time(struct device *dev, struct rtc_time *tm) | |
89 | { | |
90 | struct platform_device *pdev = to_platform_device(dev); | |
91 | struct rtc_plat_data *pdata = platform_get_drvdata(pdev); | |
f9231a0c | 92 | void __iomem *ioaddr = pdata->ioaddr_rtc; |
5ec3e4b7 AN |
93 | unsigned int year, month, day, hour, minute, second, week; |
94 | unsigned int century; | |
95 | ||
96 | /* give enough time to update RTC in case of continuous read */ | |
97 | if (pdata->last_jiffies == jiffies) | |
98 | msleep(1); | |
99 | pdata->last_jiffies = jiffies; | |
100 | writeb(RTC_READ, ioaddr + RTC_CONTROL); | |
101 | second = readb(ioaddr + RTC_SECONDS) & RTC_SECONDS_MASK; | |
102 | minute = readb(ioaddr + RTC_MINUTES); | |
103 | hour = readb(ioaddr + RTC_HOURS); | |
104 | day = readb(ioaddr + RTC_DATE); | |
105 | week = readb(ioaddr + RTC_DAY) & RTC_DAY_MASK; | |
106 | month = readb(ioaddr + RTC_MONTH); | |
107 | year = readb(ioaddr + RTC_YEAR); | |
108 | century = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK; | |
109 | writeb(0, ioaddr + RTC_CONTROL); | |
fe20ba70 AB |
110 | tm->tm_sec = bcd2bin(second); |
111 | tm->tm_min = bcd2bin(minute); | |
112 | tm->tm_hour = bcd2bin(hour); | |
113 | tm->tm_mday = bcd2bin(day); | |
114 | tm->tm_wday = bcd2bin(week); | |
115 | tm->tm_mon = bcd2bin(month) - 1; | |
5ec3e4b7 | 116 | /* year is 1900 + tm->tm_year */ |
fe20ba70 | 117 | tm->tm_year = bcd2bin(year) + bcd2bin(century) * 100 - 1900; |
5ec3e4b7 AN |
118 | |
119 | if (rtc_valid_tm(tm) < 0) { | |
120 | dev_err(dev, "retrieved date/time is not valid.\n"); | |
121 | rtc_time_to_tm(0, tm); | |
122 | } | |
123 | return 0; | |
124 | } | |
125 | ||
ff8371ac | 126 | static const struct rtc_class_ops ds1742_rtc_ops = { |
5ec3e4b7 AN |
127 | .read_time = ds1742_rtc_read_time, |
128 | .set_time = ds1742_rtc_set_time, | |
129 | }; | |
130 | ||
91a69029 ZR |
131 | static ssize_t ds1742_nvram_read(struct kobject *kobj, |
132 | struct bin_attribute *bin_attr, | |
133 | char *buf, loff_t pos, size_t size) | |
5ec3e4b7 AN |
134 | { |
135 | struct platform_device *pdev = | |
136 | to_platform_device(container_of(kobj, struct device, kobj)); | |
137 | struct rtc_plat_data *pdata = platform_get_drvdata(pdev); | |
f9231a0c | 138 | void __iomem *ioaddr = pdata->ioaddr_nvram; |
5ec3e4b7 AN |
139 | ssize_t count; |
140 | ||
f9231a0c | 141 | for (count = 0; size > 0 && pos < pdata->size_nvram; count++, size--) |
5ec3e4b7 AN |
142 | *buf++ = readb(ioaddr + pos++); |
143 | return count; | |
144 | } | |
145 | ||
91a69029 ZR |
146 | static ssize_t ds1742_nvram_write(struct kobject *kobj, |
147 | struct bin_attribute *bin_attr, | |
148 | char *buf, loff_t pos, size_t size) | |
5ec3e4b7 AN |
149 | { |
150 | struct platform_device *pdev = | |
151 | to_platform_device(container_of(kobj, struct device, kobj)); | |
152 | struct rtc_plat_data *pdata = platform_get_drvdata(pdev); | |
f9231a0c | 153 | void __iomem *ioaddr = pdata->ioaddr_nvram; |
5ec3e4b7 AN |
154 | ssize_t count; |
155 | ||
f9231a0c | 156 | for (count = 0; size > 0 && pos < pdata->size_nvram; count++, size--) |
5ec3e4b7 AN |
157 | writeb(*buf++, ioaddr + pos++); |
158 | return count; | |
159 | } | |
160 | ||
c239122d | 161 | static int __devinit ds1742_rtc_probe(struct platform_device *pdev) |
5ec3e4b7 AN |
162 | { |
163 | struct rtc_device *rtc; | |
164 | struct resource *res; | |
165 | unsigned int cen, sec; | |
166 | struct rtc_plat_data *pdata = NULL; | |
167 | void __iomem *ioaddr = NULL; | |
168 | int ret = 0; | |
169 | ||
170 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
171 | if (!res) | |
172 | return -ENODEV; | |
173 | pdata = kzalloc(sizeof(*pdata), GFP_KERNEL); | |
174 | if (!pdata) | |
175 | return -ENOMEM; | |
f9231a0c TER |
176 | pdata->size = res->end - res->start + 1; |
177 | if (!request_mem_region(res->start, pdata->size, pdev->name)) { | |
5ec3e4b7 AN |
178 | ret = -EBUSY; |
179 | goto out; | |
180 | } | |
181 | pdata->baseaddr = res->start; | |
f9231a0c | 182 | ioaddr = ioremap(pdata->baseaddr, pdata->size); |
5ec3e4b7 AN |
183 | if (!ioaddr) { |
184 | ret = -ENOMEM; | |
185 | goto out; | |
186 | } | |
f9231a0c TER |
187 | pdata->ioaddr_nvram = ioaddr; |
188 | pdata->size_nvram = pdata->size - RTC_SIZE; | |
189 | pdata->ioaddr_rtc = ioaddr + pdata->size_nvram; | |
5ec3e4b7 | 190 | |
3a729700 TER |
191 | pdata->nvram_attr.attr.name = "nvram"; |
192 | pdata->nvram_attr.attr.mode = S_IRUGO | S_IWUSR; | |
193 | pdata->nvram_attr.read = ds1742_nvram_read; | |
194 | pdata->nvram_attr.write = ds1742_nvram_write; | |
195 | pdata->nvram_attr.size = pdata->size_nvram; | |
196 | ||
5ec3e4b7 | 197 | /* turn RTC on if it was not on */ |
f9231a0c | 198 | ioaddr = pdata->ioaddr_rtc; |
5ec3e4b7 AN |
199 | sec = readb(ioaddr + RTC_SECONDS); |
200 | if (sec & RTC_STOP) { | |
201 | sec &= RTC_SECONDS_MASK; | |
202 | cen = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK; | |
203 | writeb(RTC_WRITE, ioaddr + RTC_CONTROL); | |
204 | writeb(sec, ioaddr + RTC_SECONDS); | |
205 | writeb(cen & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL); | |
206 | } | |
391b1fe6 | 207 | if (!(readb(ioaddr + RTC_DAY) & RTC_BATT_FLAG)) |
5ec3e4b7 AN |
208 | dev_warn(&pdev->dev, "voltage-low detected.\n"); |
209 | ||
210 | rtc = rtc_device_register(pdev->name, &pdev->dev, | |
211 | &ds1742_rtc_ops, THIS_MODULE); | |
212 | if (IS_ERR(rtc)) { | |
213 | ret = PTR_ERR(rtc); | |
214 | goto out; | |
215 | } | |
216 | pdata->rtc = rtc; | |
217 | pdata->last_jiffies = jiffies; | |
218 | platform_set_drvdata(pdev, pdata); | |
3a729700 TER |
219 | |
220 | ret = sysfs_create_bin_file(&pdev->dev.kobj, &pdata->nvram_attr); | |
221 | if (ret) { | |
222 | dev_err(&pdev->dev, "creating nvram file in sysfs failed\n"); | |
391b1fe6 | 223 | goto out; |
3a729700 TER |
224 | } |
225 | ||
5ec3e4b7 AN |
226 | return 0; |
227 | out: | |
391b1fe6 AN |
228 | if (pdata->rtc) |
229 | rtc_device_unregister(pdata->rtc); | |
f9231a0c TER |
230 | if (pdata->ioaddr_nvram) |
231 | iounmap(pdata->ioaddr_nvram); | |
5ec3e4b7 | 232 | if (pdata->baseaddr) |
f9231a0c | 233 | release_mem_region(pdata->baseaddr, pdata->size); |
5ec3e4b7 AN |
234 | kfree(pdata); |
235 | return ret; | |
236 | } | |
237 | ||
238 | static int __devexit ds1742_rtc_remove(struct platform_device *pdev) | |
239 | { | |
240 | struct rtc_plat_data *pdata = platform_get_drvdata(pdev); | |
241 | ||
3a729700 | 242 | sysfs_remove_bin_file(&pdev->dev.kobj, &pdata->nvram_attr); |
5ec3e4b7 | 243 | rtc_device_unregister(pdata->rtc); |
f9231a0c TER |
244 | iounmap(pdata->ioaddr_nvram); |
245 | release_mem_region(pdata->baseaddr, pdata->size); | |
5ec3e4b7 AN |
246 | kfree(pdata); |
247 | return 0; | |
248 | } | |
249 | ||
250 | static struct platform_driver ds1742_rtc_driver = { | |
251 | .probe = ds1742_rtc_probe, | |
252 | .remove = __devexit_p(ds1742_rtc_remove), | |
253 | .driver = { | |
a95e23a2 | 254 | .name = "rtc-ds1742", |
5ec3e4b7 AN |
255 | .owner = THIS_MODULE, |
256 | }, | |
257 | }; | |
258 | ||
259 | static __init int ds1742_init(void) | |
260 | { | |
261 | return platform_driver_register(&ds1742_rtc_driver); | |
262 | } | |
263 | ||
264 | static __exit void ds1742_exit(void) | |
265 | { | |
ef154ec6 | 266 | platform_driver_unregister(&ds1742_rtc_driver); |
5ec3e4b7 AN |
267 | } |
268 | ||
269 | module_init(ds1742_init); | |
270 | module_exit(ds1742_exit); | |
271 | ||
272 | MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>"); | |
273 | MODULE_DESCRIPTION("Dallas DS1742 RTC driver"); | |
274 | MODULE_LICENSE("GPL"); | |
275 | MODULE_VERSION(DRV_VERSION); | |
ad28a07b | 276 | MODULE_ALIAS("platform:rtc-ds1742"); |