Opensource [Steve Twiss] | c2a5755 | 2014-06-06 14:36:03 -0700 | [diff] [blame] | 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_DATA_LEN (DA9063_REG_COUNT_Y - DA9063_REG_COUNT_S + 1) |
| 33 | #define RTC_SEC 0 |
| 34 | #define RTC_MIN 1 |
| 35 | #define RTC_HOUR 2 |
| 36 | #define RTC_DAY 3 |
| 37 | #define RTC_MONTH 4 |
| 38 | #define RTC_YEAR 5 |
| 39 | |
| 40 | struct da9063_rtc { |
| 41 | struct rtc_device *rtc_dev; |
| 42 | struct da9063 *hw; |
| 43 | struct rtc_time alarm_time; |
| 44 | bool rtc_sync; |
| 45 | }; |
| 46 | |
| 47 | static void da9063_data_to_tm(u8 *data, struct rtc_time *tm) |
| 48 | { |
| 49 | tm->tm_sec = data[RTC_SEC] & DA9063_COUNT_SEC_MASK; |
| 50 | tm->tm_min = data[RTC_MIN] & DA9063_COUNT_MIN_MASK; |
| 51 | tm->tm_hour = data[RTC_HOUR] & DA9063_COUNT_HOUR_MASK; |
| 52 | tm->tm_mday = data[RTC_DAY] & DA9063_COUNT_DAY_MASK; |
| 53 | tm->tm_mon = MONTHS_FROM_DA9063(data[RTC_MONTH] & |
| 54 | DA9063_COUNT_MONTH_MASK); |
| 55 | tm->tm_year = YEARS_FROM_DA9063(data[RTC_YEAR] & |
| 56 | DA9063_COUNT_YEAR_MASK); |
| 57 | } |
| 58 | |
| 59 | static void da9063_tm_to_data(struct rtc_time *tm, u8 *data) |
| 60 | { |
| 61 | data[RTC_SEC] &= ~DA9063_COUNT_SEC_MASK; |
| 62 | data[RTC_SEC] |= tm->tm_sec & DA9063_COUNT_SEC_MASK; |
| 63 | |
| 64 | data[RTC_MIN] &= ~DA9063_COUNT_MIN_MASK; |
| 65 | data[RTC_MIN] |= tm->tm_min & DA9063_COUNT_MIN_MASK; |
| 66 | |
| 67 | data[RTC_HOUR] &= ~DA9063_COUNT_HOUR_MASK; |
| 68 | data[RTC_HOUR] |= tm->tm_hour & DA9063_COUNT_HOUR_MASK; |
| 69 | |
| 70 | data[RTC_DAY] &= ~DA9063_COUNT_DAY_MASK; |
| 71 | data[RTC_DAY] |= tm->tm_mday & DA9063_COUNT_DAY_MASK; |
| 72 | |
| 73 | data[RTC_MONTH] &= ~DA9063_COUNT_MONTH_MASK; |
| 74 | data[RTC_MONTH] |= MONTHS_TO_DA9063(tm->tm_mon) & |
| 75 | DA9063_COUNT_MONTH_MASK; |
| 76 | |
| 77 | data[RTC_YEAR] &= ~DA9063_COUNT_YEAR_MASK; |
| 78 | data[RTC_YEAR] |= YEARS_TO_DA9063(tm->tm_year) & |
| 79 | DA9063_COUNT_YEAR_MASK; |
| 80 | } |
| 81 | |
| 82 | static int da9063_rtc_stop_alarm(struct device *dev) |
| 83 | { |
| 84 | struct da9063_rtc *rtc = dev_get_drvdata(dev); |
| 85 | |
| 86 | return regmap_update_bits(rtc->hw->regmap, DA9063_REG_ALARM_Y, |
| 87 | DA9063_ALARM_ON, 0); |
| 88 | } |
| 89 | |
| 90 | static int da9063_rtc_start_alarm(struct device *dev) |
| 91 | { |
| 92 | struct da9063_rtc *rtc = dev_get_drvdata(dev); |
| 93 | |
| 94 | return regmap_update_bits(rtc->hw->regmap, DA9063_REG_ALARM_Y, |
| 95 | DA9063_ALARM_ON, DA9063_ALARM_ON); |
| 96 | } |
| 97 | |
| 98 | static int da9063_rtc_read_time(struct device *dev, struct rtc_time *tm) |
| 99 | { |
| 100 | struct da9063_rtc *rtc = dev_get_drvdata(dev); |
| 101 | unsigned long tm_secs; |
| 102 | unsigned long al_secs; |
| 103 | u8 data[RTC_DATA_LEN]; |
| 104 | int ret; |
| 105 | |
| 106 | ret = regmap_bulk_read(rtc->hw->regmap, DA9063_REG_COUNT_S, |
| 107 | data, RTC_DATA_LEN); |
| 108 | if (ret < 0) { |
| 109 | dev_err(dev, "Failed to read RTC time data: %d\n", ret); |
| 110 | return ret; |
| 111 | } |
| 112 | |
| 113 | if (!(data[RTC_SEC] & DA9063_RTC_READ)) { |
| 114 | dev_dbg(dev, "RTC not yet ready to be read by the host\n"); |
| 115 | return -EINVAL; |
| 116 | } |
| 117 | |
| 118 | da9063_data_to_tm(data, tm); |
| 119 | |
| 120 | rtc_tm_to_time(tm, &tm_secs); |
| 121 | rtc_tm_to_time(&rtc->alarm_time, &al_secs); |
| 122 | |
| 123 | /* handle the rtc synchronisation delay */ |
| 124 | if (rtc->rtc_sync == true && al_secs - tm_secs == 1) |
| 125 | memcpy(tm, &rtc->alarm_time, sizeof(struct rtc_time)); |
| 126 | else |
| 127 | rtc->rtc_sync = false; |
| 128 | |
| 129 | return rtc_valid_tm(tm); |
| 130 | } |
| 131 | |
| 132 | static int da9063_rtc_set_time(struct device *dev, struct rtc_time *tm) |
| 133 | { |
| 134 | struct da9063_rtc *rtc = dev_get_drvdata(dev); |
| 135 | u8 data[RTC_DATA_LEN]; |
| 136 | int ret; |
| 137 | |
| 138 | da9063_tm_to_data(tm, data); |
| 139 | ret = regmap_bulk_write(rtc->hw->regmap, DA9063_REG_COUNT_S, |
| 140 | data, RTC_DATA_LEN); |
| 141 | if (ret < 0) |
| 142 | dev_err(dev, "Failed to set RTC time data: %d\n", ret); |
| 143 | |
| 144 | return ret; |
| 145 | } |
| 146 | |
| 147 | static int da9063_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) |
| 148 | { |
| 149 | struct da9063_rtc *rtc = dev_get_drvdata(dev); |
| 150 | u8 data[RTC_DATA_LEN]; |
| 151 | int ret; |
| 152 | unsigned int val; |
| 153 | |
| 154 | ret = regmap_bulk_read(rtc->hw->regmap, DA9063_REG_ALARM_S, |
| 155 | &data[RTC_SEC], RTC_DATA_LEN); |
| 156 | if (ret < 0) |
| 157 | return ret; |
| 158 | |
| 159 | da9063_data_to_tm(data, &alrm->time); |
| 160 | |
| 161 | alrm->enabled = !!(data[RTC_YEAR] & DA9063_ALARM_ON); |
| 162 | |
| 163 | ret = regmap_read(rtc->hw->regmap, DA9063_REG_EVENT_A, &val); |
| 164 | if (ret < 0) |
| 165 | return ret; |
| 166 | |
| 167 | if (val & (DA9063_E_ALARM)) |
| 168 | alrm->pending = 1; |
| 169 | else |
| 170 | alrm->pending = 0; |
| 171 | |
| 172 | return 0; |
| 173 | } |
| 174 | |
| 175 | static int da9063_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) |
| 176 | { |
| 177 | struct da9063_rtc *rtc = dev_get_drvdata(dev); |
| 178 | u8 data[RTC_DATA_LEN]; |
| 179 | int ret; |
| 180 | |
| 181 | da9063_tm_to_data(&alrm->time, data); |
| 182 | |
| 183 | ret = da9063_rtc_stop_alarm(dev); |
| 184 | if (ret < 0) { |
| 185 | dev_err(dev, "Failed to stop alarm: %d\n", ret); |
| 186 | return ret; |
| 187 | } |
| 188 | |
| 189 | ret = regmap_bulk_write(rtc->hw->regmap, DA9063_REG_ALARM_S, |
| 190 | data, RTC_DATA_LEN); |
| 191 | if (ret < 0) { |
| 192 | dev_err(dev, "Failed to write alarm: %d\n", ret); |
| 193 | return ret; |
| 194 | } |
| 195 | |
| 196 | rtc->alarm_time = alrm->time; |
| 197 | |
| 198 | if (alrm->enabled) { |
| 199 | ret = da9063_rtc_start_alarm(dev); |
| 200 | if (ret < 0) { |
| 201 | dev_err(dev, "Failed to start alarm: %d\n", ret); |
| 202 | return ret; |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | return ret; |
| 207 | } |
| 208 | |
| 209 | static int da9063_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) |
| 210 | { |
| 211 | if (enabled) |
| 212 | return da9063_rtc_start_alarm(dev); |
| 213 | else |
| 214 | return da9063_rtc_stop_alarm(dev); |
| 215 | } |
| 216 | |
| 217 | static irqreturn_t da9063_alarm_event(int irq, void *data) |
| 218 | { |
| 219 | struct da9063_rtc *rtc = data; |
| 220 | |
| 221 | regmap_update_bits(rtc->hw->regmap, DA9063_REG_ALARM_Y, |
| 222 | DA9063_ALARM_ON, 0); |
| 223 | |
| 224 | rtc->rtc_sync = true; |
| 225 | rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF); |
| 226 | |
| 227 | return IRQ_HANDLED; |
| 228 | } |
| 229 | |
| 230 | static const struct rtc_class_ops da9063_rtc_ops = { |
| 231 | .read_time = da9063_rtc_read_time, |
| 232 | .set_time = da9063_rtc_set_time, |
| 233 | .read_alarm = da9063_rtc_read_alarm, |
| 234 | .set_alarm = da9063_rtc_set_alarm, |
| 235 | .alarm_irq_enable = da9063_rtc_alarm_irq_enable, |
| 236 | }; |
| 237 | |
| 238 | static int da9063_rtc_probe(struct platform_device *pdev) |
| 239 | { |
| 240 | struct da9063 *da9063 = dev_get_drvdata(pdev->dev.parent); |
| 241 | struct da9063_rtc *rtc; |
| 242 | int irq_alarm; |
| 243 | u8 data[RTC_DATA_LEN]; |
| 244 | int ret; |
| 245 | |
| 246 | ret = regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_E, |
| 247 | DA9063_RTC_EN, DA9063_RTC_EN); |
| 248 | if (ret < 0) { |
| 249 | dev_err(&pdev->dev, "Failed to enable RTC\n"); |
| 250 | goto err; |
| 251 | } |
| 252 | |
| 253 | ret = regmap_update_bits(da9063->regmap, DA9063_REG_EN_32K, |
| 254 | DA9063_CRYSTAL, DA9063_CRYSTAL); |
| 255 | if (ret < 0) { |
| 256 | dev_err(&pdev->dev, "Failed to run 32kHz oscillator\n"); |
| 257 | goto err; |
| 258 | } |
| 259 | |
| 260 | ret = regmap_update_bits(da9063->regmap, DA9063_REG_ALARM_S, |
| 261 | DA9063_ALARM_STATUS_TICK | DA9063_ALARM_STATUS_ALARM, |
| 262 | 0); |
| 263 | if (ret < 0) { |
| 264 | dev_err(&pdev->dev, "Failed to access RTC alarm register\n"); |
| 265 | goto err; |
| 266 | } |
| 267 | |
| 268 | ret = regmap_update_bits(da9063->regmap, DA9063_REG_ALARM_S, |
| 269 | DA9063_ALARM_STATUS_ALARM, |
| 270 | DA9063_ALARM_STATUS_ALARM); |
| 271 | if (ret < 0) { |
| 272 | dev_err(&pdev->dev, "Failed to access RTC alarm register\n"); |
| 273 | goto err; |
| 274 | } |
| 275 | |
| 276 | ret = regmap_update_bits(da9063->regmap, DA9063_REG_ALARM_Y, |
| 277 | DA9063_TICK_ON, 0); |
| 278 | if (ret < 0) { |
| 279 | dev_err(&pdev->dev, "Failed to disable TICKs\n"); |
| 280 | goto err; |
| 281 | } |
| 282 | |
| 283 | ret = regmap_bulk_read(da9063->regmap, DA9063_REG_ALARM_S, |
| 284 | data, RTC_DATA_LEN); |
| 285 | if (ret < 0) { |
| 286 | dev_err(&pdev->dev, "Failed to read initial alarm data: %d\n", |
| 287 | ret); |
| 288 | goto err; |
| 289 | } |
| 290 | |
| 291 | rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); |
| 292 | if (!rtc) |
| 293 | return -ENOMEM; |
| 294 | |
| 295 | platform_set_drvdata(pdev, rtc); |
| 296 | |
| 297 | irq_alarm = platform_get_irq_byname(pdev, "ALARM"); |
| 298 | ret = devm_request_threaded_irq(&pdev->dev, irq_alarm, NULL, |
| 299 | da9063_alarm_event, |
| 300 | IRQF_TRIGGER_LOW | IRQF_ONESHOT, |
| 301 | "ALARM", rtc); |
| 302 | if (ret) { |
| 303 | dev_err(&pdev->dev, "Failed to request ALARM IRQ %d: %d\n", |
| 304 | irq_alarm, ret); |
| 305 | goto err; |
| 306 | } |
| 307 | |
| 308 | rtc->hw = da9063; |
| 309 | rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, DA9063_DRVNAME_RTC, |
| 310 | &da9063_rtc_ops, THIS_MODULE); |
| 311 | if (IS_ERR(rtc->rtc_dev)) |
| 312 | return PTR_ERR(rtc->rtc_dev); |
| 313 | |
| 314 | da9063_data_to_tm(data, &rtc->alarm_time); |
| 315 | rtc->rtc_sync = false; |
| 316 | err: |
| 317 | return ret; |
| 318 | } |
| 319 | |
| 320 | static struct platform_driver da9063_rtc_driver = { |
| 321 | .probe = da9063_rtc_probe, |
| 322 | .driver = { |
| 323 | .name = DA9063_DRVNAME_RTC, |
| 324 | .owner = THIS_MODULE, |
| 325 | }, |
| 326 | }; |
| 327 | |
| 328 | module_platform_driver(da9063_rtc_driver); |
| 329 | |
| 330 | MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>"); |
| 331 | MODULE_DESCRIPTION("Real time clock device driver for Dialog DA9063"); |
| 332 | MODULE_LICENSE("GPL v2"); |
| 333 | MODULE_ALIAS("platform:" DA9063_DRVNAME_RTC); |