Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Dallas DS1302 RTC Support |
| 3 | * |
Alessandro Zummo | 2bfc330 | 2009-08-20 12:31:49 +0900 | [diff] [blame] | 4 | * Copyright (C) 2002 David McCullough |
| 5 | * Copyright (C) 2003 - 2007 Paul Mundt |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 6 | * |
| 7 | * This file is subject to the terms and conditions of the GNU General Public |
Alessandro Zummo | 2bfc330 | 2009-08-20 12:31:49 +0900 | [diff] [blame] | 8 | * License version 2. See the file "COPYING" in the main directory of |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 9 | * this archive for more details. |
| 10 | */ |
Alessandro Zummo | 2bfc330 | 2009-08-20 12:31:49 +0900 | [diff] [blame] | 11 | |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 12 | #include <linux/init.h> |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/kernel.h> |
| 15 | #include <linux/platform_device.h> |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 16 | #include <linux/rtc.h> |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 17 | #include <linux/io.h> |
| 18 | #include <linux/bcd.h> |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 19 | |
| 20 | #define DRV_NAME "rtc-ds1302" |
Alessandro Zummo | 2bfc330 | 2009-08-20 12:31:49 +0900 | [diff] [blame] | 21 | #define DRV_VERSION "0.1.1" |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 22 | |
| 23 | #define RTC_CMD_READ 0x81 /* Read command */ |
| 24 | #define RTC_CMD_WRITE 0x80 /* Write command */ |
| 25 | |
Sergey Yanovich | dfc657b | 2013-07-03 15:07:46 -0700 | [diff] [blame] | 26 | #define RTC_CMD_WRITE_ENABLE 0x00 /* Write enable */ |
| 27 | #define RTC_CMD_WRITE_DISABLE 0x80 /* Write disable */ |
| 28 | |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 29 | #define RTC_ADDR_RAM0 0x20 /* Address of RAM0 */ |
| 30 | #define RTC_ADDR_TCR 0x08 /* Address of trickle charge register */ |
Sergey Yanovich | dfc657b | 2013-07-03 15:07:46 -0700 | [diff] [blame] | 31 | #define RTC_ADDR_CTRL 0x07 /* Address of control register */ |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 32 | #define RTC_ADDR_YEAR 0x06 /* Address of year register */ |
| 33 | #define RTC_ADDR_DAY 0x05 /* Address of day of week register */ |
| 34 | #define RTC_ADDR_MON 0x04 /* Address of month register */ |
| 35 | #define RTC_ADDR_DATE 0x03 /* Address of day of month register */ |
| 36 | #define RTC_ADDR_HOUR 0x02 /* Address of hour register */ |
| 37 | #define RTC_ADDR_MIN 0x01 /* Address of minute register */ |
| 38 | #define RTC_ADDR_SEC 0x00 /* Address of second register */ |
| 39 | |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 40 | #ifdef CONFIG_SH_SECUREEDGE5410 |
| 41 | #include <asm/rtc.h> |
Paul Mundt | f6eec8d | 2010-10-29 19:06:53 +0900 | [diff] [blame] | 42 | #include <mach/secureedge5410.h> |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 43 | |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 44 | #define RTC_RESET 0x1000 |
| 45 | #define RTC_IODATA 0x0800 |
| 46 | #define RTC_SCLK 0x0400 |
| 47 | |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 48 | #define set_dp(x) SECUREEDGE_WRITE_IOPORT(x, 0x1c00) |
| 49 | #define get_dp() SECUREEDGE_READ_IOPORT() |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 50 | #define ds1302_set_tx() |
| 51 | #define ds1302_set_rx() |
| 52 | |
| 53 | static inline int ds1302_hw_init(void) |
| 54 | { |
| 55 | return 0; |
| 56 | } |
| 57 | |
| 58 | static inline void ds1302_reset(void) |
| 59 | { |
| 60 | set_dp(get_dp() & ~(RTC_RESET | RTC_IODATA | RTC_SCLK)); |
| 61 | } |
| 62 | |
| 63 | static inline void ds1302_clock(void) |
| 64 | { |
| 65 | set_dp(get_dp() | RTC_SCLK); /* clock high */ |
| 66 | set_dp(get_dp() & ~RTC_SCLK); /* clock low */ |
| 67 | } |
| 68 | |
| 69 | static inline void ds1302_start(void) |
| 70 | { |
| 71 | set_dp(get_dp() | RTC_RESET); |
| 72 | } |
| 73 | |
| 74 | static inline void ds1302_stop(void) |
| 75 | { |
| 76 | set_dp(get_dp() & ~RTC_RESET); |
| 77 | } |
| 78 | |
| 79 | static inline void ds1302_txbit(int bit) |
| 80 | { |
| 81 | set_dp((get_dp() & ~RTC_IODATA) | (bit ? RTC_IODATA : 0)); |
| 82 | } |
| 83 | |
| 84 | static inline int ds1302_rxbit(void) |
| 85 | { |
| 86 | return !!(get_dp() & RTC_IODATA); |
| 87 | } |
| 88 | |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 89 | #else |
| 90 | #error "Add support for your platform" |
| 91 | #endif |
| 92 | |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 93 | static void ds1302_sendbits(unsigned int val) |
| 94 | { |
| 95 | int i; |
| 96 | |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 97 | ds1302_set_tx(); |
| 98 | |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 99 | for (i = 8; (i); i--, val >>= 1) { |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 100 | ds1302_txbit(val & 0x1); |
| 101 | ds1302_clock(); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 102 | } |
| 103 | } |
| 104 | |
| 105 | static unsigned int ds1302_recvbits(void) |
| 106 | { |
| 107 | unsigned int val; |
| 108 | int i; |
| 109 | |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 110 | ds1302_set_rx(); |
| 111 | |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 112 | for (i = 0, val = 0; (i < 8); i++) { |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 113 | val |= (ds1302_rxbit() << i); |
| 114 | ds1302_clock(); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 115 | } |
| 116 | |
| 117 | return val; |
| 118 | } |
| 119 | |
| 120 | static unsigned int ds1302_readbyte(unsigned int addr) |
| 121 | { |
| 122 | unsigned int val; |
| 123 | |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 124 | ds1302_reset(); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 125 | |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 126 | ds1302_start(); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 127 | ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_READ); |
| 128 | val = ds1302_recvbits(); |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 129 | ds1302_stop(); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 130 | |
| 131 | return val; |
| 132 | } |
| 133 | |
| 134 | static void ds1302_writebyte(unsigned int addr, unsigned int val) |
| 135 | { |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 136 | ds1302_reset(); |
| 137 | |
| 138 | ds1302_start(); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 139 | ds1302_sendbits(((addr & 0x3f) << 1) | RTC_CMD_WRITE); |
| 140 | ds1302_sendbits(val); |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 141 | ds1302_stop(); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 142 | } |
| 143 | |
| 144 | static int ds1302_rtc_read_time(struct device *dev, struct rtc_time *tm) |
| 145 | { |
Adrian Bunk | fe20ba7 | 2008-10-18 20:28:41 -0700 | [diff] [blame] | 146 | tm->tm_sec = bcd2bin(ds1302_readbyte(RTC_ADDR_SEC)); |
| 147 | tm->tm_min = bcd2bin(ds1302_readbyte(RTC_ADDR_MIN)); |
| 148 | tm->tm_hour = bcd2bin(ds1302_readbyte(RTC_ADDR_HOUR)); |
| 149 | tm->tm_wday = bcd2bin(ds1302_readbyte(RTC_ADDR_DAY)); |
| 150 | tm->tm_mday = bcd2bin(ds1302_readbyte(RTC_ADDR_DATE)); |
| 151 | tm->tm_mon = bcd2bin(ds1302_readbyte(RTC_ADDR_MON)) - 1; |
| 152 | tm->tm_year = bcd2bin(ds1302_readbyte(RTC_ADDR_YEAR)); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 153 | |
| 154 | if (tm->tm_year < 70) |
| 155 | tm->tm_year += 100; |
| 156 | |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 157 | dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, " |
| 158 | "mday=%d, mon=%d, year=%d, wday=%d\n", |
Harvey Harrison | 2a4e2b878 | 2008-04-28 02:12:00 -0700 | [diff] [blame] | 159 | __func__, |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 160 | tm->tm_sec, tm->tm_min, tm->tm_hour, |
| 161 | tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday); |
| 162 | |
Alessandro Zummo | 2bfc330 | 2009-08-20 12:31:49 +0900 | [diff] [blame] | 163 | return rtc_valid_tm(tm); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 164 | } |
| 165 | |
| 166 | static int ds1302_rtc_set_time(struct device *dev, struct rtc_time *tm) |
| 167 | { |
Sergey Yanovich | dfc657b | 2013-07-03 15:07:46 -0700 | [diff] [blame] | 168 | ds1302_writebyte(RTC_ADDR_CTRL, RTC_CMD_WRITE_ENABLE); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 169 | /* Stop RTC */ |
| 170 | ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) | 0x80); |
| 171 | |
Adrian Bunk | fe20ba7 | 2008-10-18 20:28:41 -0700 | [diff] [blame] | 172 | ds1302_writebyte(RTC_ADDR_SEC, bin2bcd(tm->tm_sec)); |
| 173 | ds1302_writebyte(RTC_ADDR_MIN, bin2bcd(tm->tm_min)); |
| 174 | ds1302_writebyte(RTC_ADDR_HOUR, bin2bcd(tm->tm_hour)); |
| 175 | ds1302_writebyte(RTC_ADDR_DAY, bin2bcd(tm->tm_wday)); |
| 176 | ds1302_writebyte(RTC_ADDR_DATE, bin2bcd(tm->tm_mday)); |
| 177 | ds1302_writebyte(RTC_ADDR_MON, bin2bcd(tm->tm_mon + 1)); |
| 178 | ds1302_writebyte(RTC_ADDR_YEAR, bin2bcd(tm->tm_year % 100)); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 179 | |
| 180 | /* Start RTC */ |
| 181 | ds1302_writebyte(RTC_ADDR_SEC, ds1302_readbyte(RTC_ADDR_SEC) & ~0x80); |
| 182 | |
Sergey Yanovich | dfc657b | 2013-07-03 15:07:46 -0700 | [diff] [blame] | 183 | ds1302_writebyte(RTC_ADDR_CTRL, RTC_CMD_WRITE_DISABLE); |
| 184 | |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 185 | return 0; |
| 186 | } |
| 187 | |
| 188 | static int ds1302_rtc_ioctl(struct device *dev, unsigned int cmd, |
| 189 | unsigned long arg) |
| 190 | { |
| 191 | switch (cmd) { |
| 192 | #ifdef RTC_SET_CHARGE |
| 193 | case RTC_SET_CHARGE: |
| 194 | { |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 195 | int tcs_val; |
| 196 | |
| 197 | if (copy_from_user(&tcs_val, (int __user *)arg, sizeof(int))) |
| 198 | return -EFAULT; |
| 199 | |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 200 | ds1302_writebyte(RTC_ADDR_TCR, (0xa0 | tcs_val * 0xf)); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 201 | return 0; |
| 202 | } |
| 203 | #endif |
| 204 | } |
| 205 | |
| 206 | return -ENOIOCTLCMD; |
| 207 | } |
| 208 | |
| 209 | static struct rtc_class_ops ds1302_rtc_ops = { |
| 210 | .read_time = ds1302_rtc_read_time, |
| 211 | .set_time = ds1302_rtc_set_time, |
| 212 | .ioctl = ds1302_rtc_ioctl, |
| 213 | }; |
| 214 | |
Alessandro Zummo | 2bfc330 | 2009-08-20 12:31:49 +0900 | [diff] [blame] | 215 | static int __init ds1302_rtc_probe(struct platform_device *pdev) |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 216 | { |
Alessandro Zummo | 2bfc330 | 2009-08-20 12:31:49 +0900 | [diff] [blame] | 217 | struct rtc_device *rtc; |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 218 | |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 219 | if (ds1302_hw_init()) { |
| 220 | dev_err(&pdev->dev, "Failed to init communication channel"); |
| 221 | return -EINVAL; |
| 222 | } |
| 223 | |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 224 | /* Reset */ |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 225 | ds1302_reset(); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 226 | |
| 227 | /* Write a magic value to the DS1302 RAM, and see if it sticks. */ |
| 228 | ds1302_writebyte(RTC_ADDR_RAM0, 0x42); |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 229 | if (ds1302_readbyte(RTC_ADDR_RAM0) != 0x42) { |
| 230 | dev_err(&pdev->dev, "Failed to probe"); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 231 | return -ENODEV; |
Marc Zyngier | 72cc8e5 | 2010-05-24 14:33:47 -0700 | [diff] [blame] | 232 | } |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 233 | |
Jingoo Han | 0ea9a0e | 2013-04-29 16:19:33 -0700 | [diff] [blame] | 234 | rtc = devm_rtc_device_register(&pdev->dev, "ds1302", |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 235 | &ds1302_rtc_ops, THIS_MODULE); |
Alessandro Zummo | 2bfc330 | 2009-08-20 12:31:49 +0900 | [diff] [blame] | 236 | if (IS_ERR(rtc)) |
| 237 | return PTR_ERR(rtc); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 238 | |
| 239 | platform_set_drvdata(pdev, rtc); |
| 240 | |
| 241 | return 0; |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 242 | } |
| 243 | |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 244 | static struct platform_driver ds1302_platform_driver = { |
| 245 | .driver = { |
| 246 | .name = DRV_NAME, |
| 247 | .owner = THIS_MODULE, |
| 248 | }, |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 249 | }; |
| 250 | |
Jingoo Han | 625f5225 | 2013-04-29 16:18:39 -0700 | [diff] [blame] | 251 | module_platform_driver_probe(ds1302_platform_driver, ds1302_rtc_probe); |
Paul Mundt | 739d340 | 2008-02-06 01:38:44 -0800 | [diff] [blame] | 252 | |
| 253 | MODULE_DESCRIPTION("Dallas DS1302 RTC driver"); |
| 254 | MODULE_VERSION(DRV_VERSION); |
| 255 | MODULE_AUTHOR("Paul Mundt, David McCullough"); |
| 256 | MODULE_LICENSE("GPL v2"); |