1 /* rtc-da9063.c - Real time clock device driver for DA9063 2 * Copyright (C) 2013-14 Dialog Semiconductor Ltd. 3 * 4 * This library is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU Library General Public 6 * License as published by the Free Software Foundation; either 7 * version 2 of the License, or (at your option) any later version. 8 * 9 * This library is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * Library General Public License for more details. 13 */ 14 15 #include <linux/kernel.h> 16 #include <linux/module.h> 17 #include <linux/init.h> 18 #include <linux/platform_device.h> 19 #include <linux/interrupt.h> 20 #include <linux/rtc.h> 21 #include <linux/slab.h> 22 #include <linux/delay.h> 23 #include <linux/regmap.h> 24 #include <linux/mfd/da9063/registers.h> 25 #include <linux/mfd/da9063/core.h> 26 27 #define YEARS_TO_DA9063(year) ((year) - 100) 28 #define MONTHS_TO_DA9063(month) ((month) + 1) 29 #define YEARS_FROM_DA9063(year) ((year) + 100) 30 #define MONTHS_FROM_DA9063(month) ((month) - 1) 31 32 #define RTC_ALARM_DATA_LEN (DA9063_AD_REG_ALARM_Y - DA9063_AD_REG_ALARM_MI + 1) 33 34 #define RTC_DATA_LEN (DA9063_REG_COUNT_Y - DA9063_REG_COUNT_S + 1) 35 #define RTC_SEC 0 36 #define RTC_MIN 1 37 #define RTC_HOUR 2 38 #define RTC_DAY 3 39 #define RTC_MONTH 4 40 #define RTC_YEAR 5 41 42 struct da9063_rtc { 43 struct rtc_device *rtc_dev; 44 struct da9063 *hw; 45 struct rtc_time alarm_time; 46 bool rtc_sync; 47 int alarm_year; 48 int alarm_start; 49 int alarm_len; 50 int data_start; 51 }; 52 53 static void da9063_data_to_tm(u8 *data, struct rtc_time *tm) 54 { 55 tm->tm_sec = data[RTC_SEC] & DA9063_COUNT_SEC_MASK; 56 tm->tm_min = data[RTC_MIN] & DA9063_COUNT_MIN_MASK; 57 tm->tm_hour = data[RTC_HOUR] & DA9063_COUNT_HOUR_MASK; 58 tm->tm_mday = data[RTC_DAY] & DA9063_COUNT_DAY_MASK; 59 tm->tm_mon = MONTHS_FROM_DA9063(data[RTC_MONTH] & 60 DA9063_COUNT_MONTH_MASK); 61 tm->tm_year = YEARS_FROM_DA9063(data[RTC_YEAR] & 62 DA9063_COUNT_YEAR_MASK); 63 } 64 65 static void da9063_tm_to_data(struct rtc_time *tm, u8 *data) 66 { 67 data[RTC_SEC] &= ~DA9063_COUNT_SEC_MASK; 68 data[RTC_SEC] |= tm->tm_sec & DA9063_COUNT_SEC_MASK; 69 70 data[RTC_MIN] &= ~DA9063_COUNT_MIN_MASK; 71 data[RTC_MIN] |= tm->tm_min & DA9063_COUNT_MIN_MASK; 72 73 data[RTC_HOUR] &= ~DA9063_COUNT_HOUR_MASK; 74 data[RTC_HOUR] |= tm->tm_hour & DA9063_COUNT_HOUR_MASK; 75 76 data[RTC_DAY] &= ~DA9063_COUNT_DAY_MASK; 77 data[RTC_DAY] |= tm->tm_mday & DA9063_COUNT_DAY_MASK; 78 79 data[RTC_MONTH] &= ~DA9063_COUNT_MONTH_MASK; 80 data[RTC_MONTH] |= MONTHS_TO_DA9063(tm->tm_mon) & 81 DA9063_COUNT_MONTH_MASK; 82 83 data[RTC_YEAR] &= ~DA9063_COUNT_YEAR_MASK; 84 data[RTC_YEAR] |= YEARS_TO_DA9063(tm->tm_year) & 85 DA9063_COUNT_YEAR_MASK; 86 } 87 88 static int da9063_rtc_stop_alarm(struct device *dev) 89 { 90 struct da9063_rtc *rtc = dev_get_drvdata(dev); 91 92 return regmap_update_bits(rtc->hw->regmap, rtc->alarm_year, 93 DA9063_ALARM_ON, 0); 94 } 95 96 static int da9063_rtc_start_alarm(struct device *dev) 97 { 98 struct da9063_rtc *rtc = dev_get_drvdata(dev); 99 100 return regmap_update_bits(rtc->hw->regmap, rtc->alarm_year, 101 DA9063_ALARM_ON, DA9063_ALARM_ON); 102 } 103 104 static int da9063_rtc_read_time(struct device *dev, struct rtc_time *tm) 105 { 106 struct da9063_rtc *rtc = dev_get_drvdata(dev); 107 unsigned long tm_secs; 108 unsigned long al_secs; 109 u8 data[RTC_DATA_LEN]; 110 int ret; 111 112 ret = regmap_bulk_read(rtc->hw->regmap, DA9063_REG_COUNT_S, 113 data, RTC_DATA_LEN); 114 if (ret < 0) { 115 dev_err(dev, "Failed to read RTC time data: %d\n", ret); 116 return ret; 117 } 118 119 if (!(data[RTC_SEC] & DA9063_RTC_READ)) { 120 dev_dbg(dev, "RTC not yet ready to be read by the host\n"); 121 return -EINVAL; 122 } 123 124 da9063_data_to_tm(data, tm); 125 126 rtc_tm_to_time(tm, &tm_secs); 127 rtc_tm_to_time(&rtc->alarm_time, &al_secs); 128 129 /* handle the rtc synchronisation delay */ 130 if (rtc->rtc_sync == true && al_secs - tm_secs == 1) 131 memcpy(tm, &rtc->alarm_time, sizeof(struct rtc_time)); 132 else 133 rtc->rtc_sync = false; 134 135 return rtc_valid_tm(tm); 136 } 137 138 static int da9063_rtc_set_time(struct device *dev, struct rtc_time *tm) 139 { 140 struct da9063_rtc *rtc = dev_get_drvdata(dev); 141 u8 data[RTC_DATA_LEN]; 142 int ret; 143 144 da9063_tm_to_data(tm, data); 145 ret = regmap_bulk_write(rtc->hw->regmap, DA9063_REG_COUNT_S, 146 data, RTC_DATA_LEN); 147 if (ret < 0) 148 dev_err(dev, "Failed to set RTC time data: %d\n", ret); 149 150 return ret; 151 } 152 153 static int da9063_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) 154 { 155 struct da9063_rtc *rtc = dev_get_drvdata(dev); 156 u8 data[RTC_DATA_LEN]; 157 int ret; 158 unsigned int val; 159 160 data[RTC_SEC] = 0; 161 ret = regmap_bulk_read(rtc->hw->regmap, rtc->alarm_start, 162 &data[rtc->data_start], rtc->alarm_len); 163 if (ret < 0) 164 return ret; 165 166 da9063_data_to_tm(data, &alrm->time); 167 168 alrm->enabled = !!(data[RTC_YEAR] & DA9063_ALARM_ON); 169 170 ret = regmap_read(rtc->hw->regmap, DA9063_REG_EVENT_A, &val); 171 if (ret < 0) 172 return ret; 173 174 if (val & (DA9063_E_ALARM)) 175 alrm->pending = 1; 176 else 177 alrm->pending = 0; 178 179 return 0; 180 } 181 182 static int da9063_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) 183 { 184 struct da9063_rtc *rtc = dev_get_drvdata(dev); 185 u8 data[RTC_DATA_LEN]; 186 int ret; 187 188 da9063_tm_to_data(&alrm->time, data); 189 190 ret = da9063_rtc_stop_alarm(dev); 191 if (ret < 0) { 192 dev_err(dev, "Failed to stop alarm: %d\n", ret); 193 return ret; 194 } 195 196 ret = regmap_bulk_write(rtc->hw->regmap, rtc->alarm_start, 197 &data[rtc->data_start], rtc->alarm_len); 198 if (ret < 0) { 199 dev_err(dev, "Failed to write alarm: %d\n", ret); 200 return ret; 201 } 202 203 da9063_data_to_tm(data, &rtc->alarm_time); 204 205 if (alrm->enabled) { 206 ret = da9063_rtc_start_alarm(dev); 207 if (ret < 0) { 208 dev_err(dev, "Failed to start alarm: %d\n", ret); 209 return ret; 210 } 211 } 212 213 return ret; 214 } 215 216 static int da9063_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) 217 { 218 if (enabled) 219 return da9063_rtc_start_alarm(dev); 220 else 221 return da9063_rtc_stop_alarm(dev); 222 } 223 224 static irqreturn_t da9063_alarm_event(int irq, void *data) 225 { 226 struct da9063_rtc *rtc = data; 227 228 regmap_update_bits(rtc->hw->regmap, rtc->alarm_year, 229 DA9063_ALARM_ON, 0); 230 231 rtc->rtc_sync = true; 232 rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF); 233 234 return IRQ_HANDLED; 235 } 236 237 static const struct rtc_class_ops da9063_rtc_ops = { 238 .read_time = da9063_rtc_read_time, 239 .set_time = da9063_rtc_set_time, 240 .read_alarm = da9063_rtc_read_alarm, 241 .set_alarm = da9063_rtc_set_alarm, 242 .alarm_irq_enable = da9063_rtc_alarm_irq_enable, 243 }; 244 245 static int da9063_rtc_probe(struct platform_device *pdev) 246 { 247 struct da9063 *da9063 = dev_get_drvdata(pdev->dev.parent); 248 struct da9063_rtc *rtc; 249 int irq_alarm; 250 u8 data[RTC_DATA_LEN]; 251 int ret; 252 253 ret = regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_E, 254 DA9063_RTC_EN, DA9063_RTC_EN); 255 if (ret < 0) { 256 dev_err(&pdev->dev, "Failed to enable RTC\n"); 257 goto err; 258 } 259 260 ret = regmap_update_bits(da9063->regmap, DA9063_REG_EN_32K, 261 DA9063_CRYSTAL, DA9063_CRYSTAL); 262 if (ret < 0) { 263 dev_err(&pdev->dev, "Failed to run 32kHz oscillator\n"); 264 goto err; 265 } 266 267 rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); 268 if (!rtc) 269 return -ENOMEM; 270 271 if (da9063->variant_code == PMIC_DA9063_AD) { 272 rtc->alarm_year = DA9063_AD_REG_ALARM_Y; 273 rtc->alarm_start = DA9063_AD_REG_ALARM_MI; 274 rtc->alarm_len = RTC_ALARM_DATA_LEN; 275 rtc->data_start = RTC_MIN; 276 } else { 277 rtc->alarm_year = DA9063_BB_REG_ALARM_Y; 278 rtc->alarm_start = DA9063_BB_REG_ALARM_S; 279 rtc->alarm_len = RTC_DATA_LEN; 280 rtc->data_start = RTC_SEC; 281 } 282 283 ret = regmap_update_bits(da9063->regmap, rtc->alarm_start, 284 DA9063_ALARM_STATUS_TICK | DA9063_ALARM_STATUS_ALARM, 285 0); 286 if (ret < 0) { 287 dev_err(&pdev->dev, "Failed to access RTC alarm register\n"); 288 goto err; 289 } 290 291 ret = regmap_update_bits(da9063->regmap, rtc->alarm_start, 292 DA9063_ALARM_STATUS_ALARM, 293 DA9063_ALARM_STATUS_ALARM); 294 if (ret < 0) { 295 dev_err(&pdev->dev, "Failed to access RTC alarm register\n"); 296 goto err; 297 } 298 299 ret = regmap_update_bits(da9063->regmap, rtc->alarm_year, 300 DA9063_TICK_ON, 0); 301 if (ret < 0) { 302 dev_err(&pdev->dev, "Failed to disable TICKs\n"); 303 goto err; 304 } 305 306 data[RTC_SEC] = 0; 307 ret = regmap_bulk_read(da9063->regmap, rtc->alarm_start, 308 &data[rtc->data_start], rtc->alarm_len); 309 if (ret < 0) { 310 dev_err(&pdev->dev, "Failed to read initial alarm data: %d\n", 311 ret); 312 goto err; 313 } 314 315 platform_set_drvdata(pdev, rtc); 316 317 irq_alarm = platform_get_irq_byname(pdev, "ALARM"); 318 ret = devm_request_threaded_irq(&pdev->dev, irq_alarm, NULL, 319 da9063_alarm_event, 320 IRQF_TRIGGER_LOW | IRQF_ONESHOT, 321 "ALARM", rtc); 322 if (ret) { 323 dev_err(&pdev->dev, "Failed to request ALARM IRQ %d: %d\n", 324 irq_alarm, ret); 325 goto err; 326 } 327 328 rtc->hw = da9063; 329 rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, DA9063_DRVNAME_RTC, 330 &da9063_rtc_ops, THIS_MODULE); 331 if (IS_ERR(rtc->rtc_dev)) 332 return PTR_ERR(rtc->rtc_dev); 333 334 da9063_data_to_tm(data, &rtc->alarm_time); 335 rtc->rtc_sync = false; 336 err: 337 return ret; 338 } 339 340 static struct platform_driver da9063_rtc_driver = { 341 .probe = da9063_rtc_probe, 342 .driver = { 343 .name = DA9063_DRVNAME_RTC, 344 .owner = THIS_MODULE, 345 }, 346 }; 347 348 module_platform_driver(da9063_rtc_driver); 349 350 MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>"); 351 MODULE_DESCRIPTION("Real time clock device driver for Dialog DA9063"); 352 MODULE_LICENSE("GPL v2"); 353 MODULE_ALIAS("platform:" DA9063_DRVNAME_RTC); 354