Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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. |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 9 | * |
| 10 | * Copyright (C) 2006 Torsten Ertbjerg Rasmussen <tr@newtec.dk> |
| 11 | * - nvram size determined from resource |
| 12 | * - this ds1742 driver now supports ds1743. |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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 | |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 24 | #define DRV_VERSION "0.3" |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 25 | |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 26 | #define RTC_SIZE 8 |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 27 | |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 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 |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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; |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 54 | void __iomem *ioaddr_nvram; |
| 55 | void __iomem *ioaddr_rtc; |
| 56 | size_t size_nvram; |
| 57 | size_t size; |
David Gibson | 2e3e31c | 2007-09-18 22:46:28 -0700 | [diff] [blame] | 58 | resource_size_t baseaddr; |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 59 | unsigned long last_jiffies; |
Torsten Ertbjerg Rasmussen | 3a72970 | 2009-06-17 16:26:07 -0700 | [diff] [blame] | 60 | struct bin_attribute nvram_attr; |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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); |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 67 | void __iomem *ioaddr = pdata->ioaddr_rtc; |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 68 | u8 century; |
| 69 | |
Adrian Bunk | fe20ba7 | 2008-10-18 20:28:41 -0700 | [diff] [blame] | 70 | century = bin2bcd((tm->tm_year + 1900) / 100); |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 71 | |
| 72 | writeb(RTC_WRITE, ioaddr + RTC_CONTROL); |
| 73 | |
Adrian Bunk | fe20ba7 | 2008-10-18 20:28:41 -0700 | [diff] [blame] | 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); |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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); |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 92 | void __iomem *ioaddr = pdata->ioaddr_rtc; |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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); |
Adrian Bunk | fe20ba7 | 2008-10-18 20:28:41 -0700 | [diff] [blame] | 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; |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 116 | /* year is 1900 + tm->tm_year */ |
Adrian Bunk | fe20ba7 | 2008-10-18 20:28:41 -0700 | [diff] [blame] | 117 | tm->tm_year = bcd2bin(year) + bcd2bin(century) * 100 - 1900; |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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 | |
David Brownell | ff8371a | 2006-09-30 23:28:17 -0700 | [diff] [blame] | 126 | static const struct rtc_class_ops ds1742_rtc_ops = { |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 127 | .read_time = ds1742_rtc_read_time, |
| 128 | .set_time = ds1742_rtc_set_time, |
| 129 | }; |
| 130 | |
Zhang Rui | 91a6902 | 2007-06-09 13:57:22 +0800 | [diff] [blame] | 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) |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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); |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 138 | void __iomem *ioaddr = pdata->ioaddr_nvram; |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 139 | ssize_t count; |
| 140 | |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 141 | for (count = 0; size > 0 && pos < pdata->size_nvram; count++, size--) |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 142 | *buf++ = readb(ioaddr + pos++); |
| 143 | return count; |
| 144 | } |
| 145 | |
Zhang Rui | 91a6902 | 2007-06-09 13:57:22 +0800 | [diff] [blame] | 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) |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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); |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 153 | void __iomem *ioaddr = pdata->ioaddr_nvram; |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 154 | ssize_t count; |
| 155 | |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 156 | for (count = 0; size > 0 && pos < pdata->size_nvram; count++, size--) |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 157 | writeb(*buf++, ioaddr + pos++); |
| 158 | return count; |
| 159 | } |
| 160 | |
Prarit Bhargava | c239122 | 2007-02-12 00:52:29 -0800 | [diff] [blame] | 161 | static int __devinit ds1742_rtc_probe(struct platform_device *pdev) |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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; |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 176 | pdata->size = res->end - res->start + 1; |
| 177 | if (!request_mem_region(res->start, pdata->size, pdev->name)) { |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 178 | ret = -EBUSY; |
| 179 | goto out; |
| 180 | } |
| 181 | pdata->baseaddr = res->start; |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 182 | ioaddr = ioremap(pdata->baseaddr, pdata->size); |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 183 | if (!ioaddr) { |
| 184 | ret = -ENOMEM; |
| 185 | goto out; |
| 186 | } |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 187 | pdata->ioaddr_nvram = ioaddr; |
| 188 | pdata->size_nvram = pdata->size - RTC_SIZE; |
| 189 | pdata->ioaddr_rtc = ioaddr + pdata->size_nvram; |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 190 | |
Torsten Ertbjerg Rasmussen | 3a72970 | 2009-06-17 16:26:07 -0700 | [diff] [blame] | 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 | |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 197 | /* turn RTC on if it was not on */ |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 198 | ioaddr = pdata->ioaddr_rtc; |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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 | } |
Atsushi Nemoto | 391b1fe | 2006-09-30 23:28:18 -0700 | [diff] [blame] | 207 | if (!(readb(ioaddr + RTC_DAY) & RTC_BATT_FLAG)) |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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); |
Torsten Ertbjerg Rasmussen | 3a72970 | 2009-06-17 16:26:07 -0700 | [diff] [blame] | 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"); |
Atsushi Nemoto | 391b1fe | 2006-09-30 23:28:18 -0700 | [diff] [blame] | 223 | goto out; |
Torsten Ertbjerg Rasmussen | 3a72970 | 2009-06-17 16:26:07 -0700 | [diff] [blame] | 224 | } |
| 225 | |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 226 | return 0; |
| 227 | out: |
Atsushi Nemoto | 391b1fe | 2006-09-30 23:28:18 -0700 | [diff] [blame] | 228 | if (pdata->rtc) |
| 229 | rtc_device_unregister(pdata->rtc); |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 230 | if (pdata->ioaddr_nvram) |
| 231 | iounmap(pdata->ioaddr_nvram); |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 232 | if (pdata->baseaddr) |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 233 | release_mem_region(pdata->baseaddr, pdata->size); |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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 | |
Torsten Ertbjerg Rasmussen | 3a72970 | 2009-06-17 16:26:07 -0700 | [diff] [blame] | 242 | sysfs_remove_bin_file(&pdev->dev.kobj, &pdata->nvram_attr); |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 243 | rtc_device_unregister(pdata->rtc); |
Torsten Ertbjerg Rasmussen | f9231a0 | 2006-12-06 20:39:41 -0800 | [diff] [blame] | 244 | iounmap(pdata->ioaddr_nvram); |
| 245 | release_mem_region(pdata->baseaddr, pdata->size); |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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 = { |
Atsushi Nemoto | a95e23a | 2007-10-16 01:28:18 -0700 | [diff] [blame] | 254 | .name = "rtc-ds1742", |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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 | { |
Atsushi Nemoto | ef154ec | 2007-07-21 04:37:55 -0700 | [diff] [blame] | 266 | platform_driver_unregister(&ds1742_rtc_driver); |
Atsushi Nemoto | 5ec3e4b | 2006-06-25 05:48:29 -0700 | [diff] [blame] | 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); |
Kay Sievers | ad28a07 | 2008-04-10 21:29:25 -0700 | [diff] [blame] | 276 | MODULE_ALIAS("platform:rtc-ds1742"); |