1 /* 2 * RTC driver for Maxim MAX8998 3 * 4 * Copyright (C) 2010 Samsung Electronics Co.Ltd 5 * Author: Minkyu Kang <mk7.kang@samsung.com> 6 * Author: Joonyoung Shim <jy0922.shim@samsung.com> 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License as published by the 10 * Free Software Foundation; either version 2 of the License, or (at your 11 * option) any later version. 12 * 13 */ 14 15 #include <linux/module.h> 16 #include <linux/i2c.h> 17 #include <linux/slab.h> 18 #include <linux/bcd.h> 19 #include <linux/rtc.h> 20 #include <linux/platform_device.h> 21 #include <linux/mfd/max8998.h> 22 #include <linux/mfd/max8998-private.h> 23 24 #define MAX8998_RTC_SEC 0x00 25 #define MAX8998_RTC_MIN 0x01 26 #define MAX8998_RTC_HOUR 0x02 27 #define MAX8998_RTC_WEEKDAY 0x03 28 #define MAX8998_RTC_DATE 0x04 29 #define MAX8998_RTC_MONTH 0x05 30 #define MAX8998_RTC_YEAR1 0x06 31 #define MAX8998_RTC_YEAR2 0x07 32 #define MAX8998_ALARM0_SEC 0x08 33 #define MAX8998_ALARM0_MIN 0x09 34 #define MAX8998_ALARM0_HOUR 0x0a 35 #define MAX8998_ALARM0_WEEKDAY 0x0b 36 #define MAX8998_ALARM0_DATE 0x0c 37 #define MAX8998_ALARM0_MONTH 0x0d 38 #define MAX8998_ALARM0_YEAR1 0x0e 39 #define MAX8998_ALARM0_YEAR2 0x0f 40 #define MAX8998_ALARM1_SEC 0x10 41 #define MAX8998_ALARM1_MIN 0x11 42 #define MAX8998_ALARM1_HOUR 0x12 43 #define MAX8998_ALARM1_WEEKDAY 0x13 44 #define MAX8998_ALARM1_DATE 0x14 45 #define MAX8998_ALARM1_MONTH 0x15 46 #define MAX8998_ALARM1_YEAR1 0x16 47 #define MAX8998_ALARM1_YEAR2 0x17 48 #define MAX8998_ALARM0_CONF 0x18 49 #define MAX8998_ALARM1_CONF 0x19 50 #define MAX8998_RTC_STATUS 0x1a 51 #define MAX8998_WTSR_SMPL_CNTL 0x1b 52 #define MAX8998_TEST 0x1f 53 54 #define HOUR_12 (1 << 7) 55 #define HOUR_PM (1 << 5) 56 #define ALARM0_STATUS (1 << 1) 57 #define ALARM1_STATUS (1 << 2) 58 59 enum { 60 RTC_SEC = 0, 61 RTC_MIN, 62 RTC_HOUR, 63 RTC_WEEKDAY, 64 RTC_DATE, 65 RTC_MONTH, 66 RTC_YEAR1, 67 RTC_YEAR2, 68 }; 69 70 struct max8998_rtc_info { 71 struct device *dev; 72 struct max8998_dev *max8998; 73 struct i2c_client *rtc; 74 struct rtc_device *rtc_dev; 75 int irq; 76 }; 77 78 static void max8998_data_to_tm(u8 *data, struct rtc_time *tm) 79 { 80 tm->tm_sec = bcd2bin(data[RTC_SEC]); 81 tm->tm_min = bcd2bin(data[RTC_MIN]); 82 if (data[RTC_HOUR] & HOUR_12) { 83 tm->tm_hour = bcd2bin(data[RTC_HOUR] & 0x1f); 84 if (data[RTC_HOUR] & HOUR_PM) 85 tm->tm_hour += 12; 86 } else 87 tm->tm_hour = bcd2bin(data[RTC_HOUR] & 0x3f); 88 89 tm->tm_wday = data[RTC_WEEKDAY] & 0x07; 90 tm->tm_mday = bcd2bin(data[RTC_DATE]); 91 tm->tm_mon = bcd2bin(data[RTC_MONTH]); 92 tm->tm_year = bcd2bin(data[RTC_YEAR1]) + bcd2bin(data[RTC_YEAR2]) * 100; 93 tm->tm_year -= 1900; 94 } 95 96 static void max8998_tm_to_data(struct rtc_time *tm, u8 *data) 97 { 98 data[RTC_SEC] = bin2bcd(tm->tm_sec); 99 data[RTC_MIN] = bin2bcd(tm->tm_min); 100 data[RTC_HOUR] = bin2bcd(tm->tm_hour); 101 data[RTC_WEEKDAY] = tm->tm_wday; 102 data[RTC_DATE] = bin2bcd(tm->tm_mday); 103 data[RTC_MONTH] = bin2bcd(tm->tm_mon); 104 data[RTC_YEAR1] = bin2bcd(tm->tm_year % 100); 105 data[RTC_YEAR2] = bin2bcd((tm->tm_year + 1900) / 100); 106 } 107 108 static int max8998_rtc_read_time(struct device *dev, struct rtc_time *tm) 109 { 110 struct max8998_rtc_info *info = dev_get_drvdata(dev); 111 u8 data[8]; 112 int ret; 113 114 ret = max8998_bulk_read(info->rtc, MAX8998_RTC_SEC, 8, data); 115 if (ret < 0) 116 return ret; 117 118 max8998_data_to_tm(data, tm); 119 120 return rtc_valid_tm(tm); 121 } 122 123 static int max8998_rtc_set_time(struct device *dev, struct rtc_time *tm) 124 { 125 struct max8998_rtc_info *info = dev_get_drvdata(dev); 126 u8 data[8]; 127 128 max8998_tm_to_data(tm, data); 129 130 return max8998_bulk_write(info->rtc, MAX8998_RTC_SEC, 8, data); 131 } 132 133 static int max8998_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) 134 { 135 struct max8998_rtc_info *info = dev_get_drvdata(dev); 136 u8 data[8]; 137 u8 val; 138 int ret; 139 140 ret = max8998_bulk_read(info->rtc, MAX8998_ALARM0_SEC, 8, data); 141 if (ret < 0) 142 return ret; 143 144 max8998_data_to_tm(data, &alrm->time); 145 146 ret = max8998_read_reg(info->rtc, MAX8998_ALARM0_CONF, &val); 147 if (ret < 0) 148 return ret; 149 150 alrm->enabled = !!val; 151 152 ret = max8998_read_reg(info->rtc, MAX8998_RTC_STATUS, &val); 153 if (ret < 0) 154 return ret; 155 156 if (val & ALARM0_STATUS) 157 alrm->pending = 1; 158 else 159 alrm->pending = 0; 160 161 return 0; 162 } 163 164 static int max8998_rtc_stop_alarm(struct max8998_rtc_info *info) 165 { 166 return max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, 0); 167 } 168 169 static int max8998_rtc_start_alarm(struct max8998_rtc_info *info) 170 { 171 return max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, 0x77); 172 } 173 174 static int max8998_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) 175 { 176 struct max8998_rtc_info *info = dev_get_drvdata(dev); 177 u8 data[8]; 178 int ret; 179 180 max8998_tm_to_data(&alrm->time, data); 181 182 ret = max8998_rtc_stop_alarm(info); 183 if (ret < 0) 184 return ret; 185 186 ret = max8998_bulk_write(info->rtc, MAX8998_ALARM0_SEC, 8, data); 187 if (ret < 0) 188 return ret; 189 190 if (alrm->enabled) 191 return max8998_rtc_start_alarm(info); 192 193 return 0; 194 } 195 196 static int max8998_rtc_alarm_irq_enable(struct device *dev, 197 unsigned int enabled) 198 { 199 struct max8998_rtc_info *info = dev_get_drvdata(dev); 200 201 if (enabled) 202 return max8998_rtc_start_alarm(info); 203 else 204 return max8998_rtc_stop_alarm(info); 205 } 206 207 static irqreturn_t max8998_rtc_alarm_irq(int irq, void *data) 208 { 209 struct max8998_rtc_info *info = data; 210 211 rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF); 212 213 return IRQ_HANDLED; 214 } 215 216 static const struct rtc_class_ops max8998_rtc_ops = { 217 .read_time = max8998_rtc_read_time, 218 .set_time = max8998_rtc_set_time, 219 .read_alarm = max8998_rtc_read_alarm, 220 .set_alarm = max8998_rtc_set_alarm, 221 .alarm_irq_enable = max8998_rtc_alarm_irq_enable, 222 }; 223 224 static int __devinit max8998_rtc_probe(struct platform_device *pdev) 225 { 226 struct max8998_dev *max8998 = dev_get_drvdata(pdev->dev.parent); 227 struct max8998_rtc_info *info; 228 int ret; 229 230 info = kzalloc(sizeof(struct max8998_rtc_info), GFP_KERNEL); 231 if (!info) 232 return -ENOMEM; 233 234 info->dev = &pdev->dev; 235 info->max8998 = max8998; 236 info->rtc = max8998->rtc; 237 info->irq = max8998->irq_base + MAX8998_IRQ_ALARM0; 238 239 info->rtc_dev = rtc_device_register("max8998-rtc", &pdev->dev, 240 &max8998_rtc_ops, THIS_MODULE); 241 242 if (IS_ERR(info->rtc_dev)) { 243 ret = PTR_ERR(info->rtc_dev); 244 dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret); 245 goto out_rtc; 246 } 247 248 platform_set_drvdata(pdev, info); 249 250 ret = request_threaded_irq(info->irq, NULL, max8998_rtc_alarm_irq, 0, 251 "rtc-alarm0", info); 252 if (ret < 0) 253 dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n", 254 info->irq, ret); 255 256 return 0; 257 258 out_rtc: 259 kfree(info); 260 return ret; 261 } 262 263 static int __devexit max8998_rtc_remove(struct platform_device *pdev) 264 { 265 struct max8998_rtc_info *info = platform_get_drvdata(pdev); 266 267 if (info) { 268 free_irq(info->irq, info); 269 rtc_device_unregister(info->rtc_dev); 270 kfree(info); 271 } 272 273 return 0; 274 } 275 276 static struct platform_driver max8998_rtc_driver = { 277 .driver = { 278 .name = "max8998-rtc", 279 .owner = THIS_MODULE, 280 }, 281 .probe = max8998_rtc_probe, 282 .remove = __devexit_p(max8998_rtc_remove), 283 }; 284 285 static int __init max8998_rtc_init(void) 286 { 287 return platform_driver_register(&max8998_rtc_driver); 288 } 289 module_init(max8998_rtc_init); 290 291 static void __exit max8998_rtc_exit(void) 292 { 293 platform_driver_unregister(&max8998_rtc_driver); 294 } 295 module_exit(max8998_rtc_exit); 296 297 MODULE_AUTHOR("Minkyu Kang <mk7.kang@samsung.com>"); 298 MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>"); 299 MODULE_DESCRIPTION("Maxim MAX8998 RTC driver"); 300 MODULE_LICENSE("GPL"); 301