1 /* 2 * Real time clock driver for DA9055 3 * 4 * Copyright(c) 2012 Dialog Semiconductor Ltd. 5 * 6 * Author: Dajun Dajun Chen <dajun.chen@diasemi.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 * 13 */ 14 15 #include <linux/module.h> 16 #include <linux/platform_device.h> 17 #include <linux/rtc.h> 18 19 #include <linux/mfd/da9055/core.h> 20 #include <linux/mfd/da9055/reg.h> 21 #include <linux/mfd/da9055/pdata.h> 22 23 struct da9055_rtc { 24 struct rtc_device *rtc; 25 struct da9055 *da9055; 26 int alarm_enable; 27 }; 28 29 static int da9055_rtc_enable_alarm(struct da9055_rtc *rtc, bool enable) 30 { 31 int ret; 32 if (enable) { 33 ret = da9055_reg_update(rtc->da9055, DA9055_REG_ALARM_Y, 34 DA9055_RTC_ALM_EN, 35 DA9055_RTC_ALM_EN); 36 if (ret != 0) 37 dev_err(rtc->da9055->dev, "Failed to enable ALM: %d\n", 38 ret); 39 rtc->alarm_enable = 1; 40 } else { 41 ret = da9055_reg_update(rtc->da9055, DA9055_REG_ALARM_Y, 42 DA9055_RTC_ALM_EN, 0); 43 if (ret != 0) 44 dev_err(rtc->da9055->dev, 45 "Failed to disable ALM: %d\n", ret); 46 rtc->alarm_enable = 0; 47 } 48 return ret; 49 } 50 51 static irqreturn_t da9055_rtc_alm_irq(int irq, void *data) 52 { 53 struct da9055_rtc *rtc = data; 54 55 da9055_rtc_enable_alarm(rtc, 0); 56 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF); 57 58 return IRQ_HANDLED; 59 } 60 61 static int da9055_read_alarm(struct da9055 *da9055, struct rtc_time *rtc_tm) 62 { 63 int ret; 64 uint8_t v[5]; 65 66 ret = da9055_group_read(da9055, DA9055_REG_ALARM_MI, 5, v); 67 if (ret != 0) { 68 dev_err(da9055->dev, "Failed to group read ALM: %d\n", ret); 69 return ret; 70 } 71 72 rtc_tm->tm_year = (v[4] & DA9055_RTC_ALM_YEAR) + 100; 73 rtc_tm->tm_mon = (v[3] & DA9055_RTC_ALM_MONTH) - 1; 74 rtc_tm->tm_mday = v[2] & DA9055_RTC_ALM_DAY; 75 rtc_tm->tm_hour = v[1] & DA9055_RTC_ALM_HOUR; 76 rtc_tm->tm_min = v[0] & DA9055_RTC_ALM_MIN; 77 rtc_tm->tm_sec = 0; 78 79 return rtc_valid_tm(rtc_tm); 80 } 81 82 static int da9055_set_alarm(struct da9055 *da9055, struct rtc_time *rtc_tm) 83 { 84 int ret; 85 uint8_t v[2]; 86 87 rtc_tm->tm_year -= 100; 88 rtc_tm->tm_mon += 1; 89 90 ret = da9055_reg_update(da9055, DA9055_REG_ALARM_MI, 91 DA9055_RTC_ALM_MIN, rtc_tm->tm_min); 92 if (ret != 0) { 93 dev_err(da9055->dev, "Failed to write ALRM MIN: %d\n", ret); 94 return ret; 95 } 96 97 v[0] = rtc_tm->tm_hour; 98 v[1] = rtc_tm->tm_mday; 99 100 ret = da9055_group_write(da9055, DA9055_REG_ALARM_H, 2, v); 101 if (ret < 0) 102 return ret; 103 104 ret = da9055_reg_update(da9055, DA9055_REG_ALARM_MO, 105 DA9055_RTC_ALM_MONTH, rtc_tm->tm_mon); 106 if (ret < 0) 107 dev_err(da9055->dev, "Failed to write ALM Month:%d\n", ret); 108 109 ret = da9055_reg_update(da9055, DA9055_REG_ALARM_Y, 110 DA9055_RTC_ALM_YEAR, rtc_tm->tm_year); 111 if (ret < 0) 112 dev_err(da9055->dev, "Failed to write ALM Year:%d\n", ret); 113 114 return ret; 115 } 116 117 static int da9055_rtc_get_alarm_status(struct da9055 *da9055) 118 { 119 int ret; 120 121 ret = da9055_reg_read(da9055, DA9055_REG_ALARM_Y); 122 if (ret < 0) { 123 dev_err(da9055->dev, "Failed to read ALM: %d\n", ret); 124 return ret; 125 } 126 ret &= DA9055_RTC_ALM_EN; 127 return (ret > 0) ? 1 : 0; 128 } 129 130 static int da9055_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm) 131 { 132 struct da9055_rtc *rtc = dev_get_drvdata(dev); 133 uint8_t v[6]; 134 int ret; 135 136 ret = da9055_reg_read(rtc->da9055, DA9055_REG_COUNT_S); 137 if (ret < 0) 138 return ret; 139 140 /* 141 * Registers are only valid when RTC_READ 142 * status bit is asserted 143 */ 144 if (!(ret & DA9055_RTC_READ)) 145 return -EBUSY; 146 147 ret = da9055_group_read(rtc->da9055, DA9055_REG_COUNT_S, 6, v); 148 if (ret < 0) { 149 dev_err(rtc->da9055->dev, "Failed to read RTC time : %d\n", 150 ret); 151 return ret; 152 } 153 154 rtc_tm->tm_year = (v[5] & DA9055_RTC_YEAR) + 100; 155 rtc_tm->tm_mon = (v[4] & DA9055_RTC_MONTH) - 1; 156 rtc_tm->tm_mday = v[3] & DA9055_RTC_DAY; 157 rtc_tm->tm_hour = v[2] & DA9055_RTC_HOUR; 158 rtc_tm->tm_min = v[1] & DA9055_RTC_MIN; 159 rtc_tm->tm_sec = v[0] & DA9055_RTC_SEC; 160 161 return 0; 162 } 163 164 static int da9055_rtc_set_time(struct device *dev, struct rtc_time *tm) 165 { 166 struct da9055_rtc *rtc; 167 uint8_t v[6]; 168 169 rtc = dev_get_drvdata(dev); 170 171 v[0] = tm->tm_sec; 172 v[1] = tm->tm_min; 173 v[2] = tm->tm_hour; 174 v[3] = tm->tm_mday; 175 v[4] = tm->tm_mon + 1; 176 v[5] = tm->tm_year - 100; 177 178 return da9055_group_write(rtc->da9055, DA9055_REG_COUNT_S, 6, v); 179 } 180 181 static int da9055_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) 182 { 183 int ret; 184 struct rtc_time *tm = &alrm->time; 185 struct da9055_rtc *rtc = dev_get_drvdata(dev); 186 187 ret = da9055_read_alarm(rtc->da9055, tm); 188 189 if (ret) 190 return ret; 191 192 alrm->enabled = da9055_rtc_get_alarm_status(rtc->da9055); 193 194 return 0; 195 } 196 197 static int da9055_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) 198 { 199 int ret; 200 struct rtc_time *tm = &alrm->time; 201 struct da9055_rtc *rtc = dev_get_drvdata(dev); 202 203 ret = da9055_rtc_enable_alarm(rtc, 0); 204 if (ret < 0) 205 return ret; 206 207 ret = da9055_set_alarm(rtc->da9055, tm); 208 if (ret) 209 return ret; 210 211 ret = da9055_rtc_enable_alarm(rtc, 1); 212 213 return ret; 214 } 215 216 static int da9055_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) 217 { 218 struct da9055_rtc *rtc = dev_get_drvdata(dev); 219 220 return da9055_rtc_enable_alarm(rtc, enabled); 221 } 222 223 static const struct rtc_class_ops da9055_rtc_ops = { 224 .read_time = da9055_rtc_read_time, 225 .set_time = da9055_rtc_set_time, 226 .read_alarm = da9055_rtc_read_alarm, 227 .set_alarm = da9055_rtc_set_alarm, 228 .alarm_irq_enable = da9055_rtc_alarm_irq_enable, 229 }; 230 231 static int da9055_rtc_device_init(struct da9055 *da9055, 232 struct da9055_pdata *pdata) 233 { 234 int ret; 235 236 /* Enable RTC and the internal Crystal */ 237 ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B, 238 DA9055_RTC_EN, DA9055_RTC_EN); 239 if (ret < 0) 240 return ret; 241 ret = da9055_reg_update(da9055, DA9055_REG_EN_32K, 242 DA9055_CRYSTAL_EN, DA9055_CRYSTAL_EN); 243 if (ret < 0) 244 return ret; 245 246 /* Enable RTC in Power Down mode */ 247 ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B, 248 DA9055_RTC_MODE_PD, DA9055_RTC_MODE_PD); 249 if (ret < 0) 250 return ret; 251 252 /* Enable RTC in Reset mode */ 253 if (pdata && pdata->reset_enable) { 254 ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B, 255 DA9055_RTC_MODE_SD, 256 DA9055_RTC_MODE_SD << 257 DA9055_RTC_MODE_SD_SHIFT); 258 if (ret < 0) 259 return ret; 260 } 261 262 /* Disable the RTC TICK ALM */ 263 ret = da9055_reg_update(da9055, DA9055_REG_ALARM_MO, 264 DA9055_RTC_TICK_WAKE_MASK, 0); 265 if (ret < 0) 266 return ret; 267 268 return 0; 269 } 270 271 static int da9055_rtc_probe(struct platform_device *pdev) 272 { 273 struct da9055_rtc *rtc; 274 struct da9055_pdata *pdata = NULL; 275 int ret, alm_irq; 276 277 rtc = devm_kzalloc(&pdev->dev, sizeof(struct da9055_rtc), GFP_KERNEL); 278 if (!rtc) 279 return -ENOMEM; 280 281 rtc->da9055 = dev_get_drvdata(pdev->dev.parent); 282 pdata = dev_get_platdata(rtc->da9055->dev); 283 platform_set_drvdata(pdev, rtc); 284 285 ret = da9055_rtc_device_init(rtc->da9055, pdata); 286 if (ret < 0) 287 goto err_rtc; 288 289 ret = da9055_reg_read(rtc->da9055, DA9055_REG_ALARM_Y); 290 if (ret < 0) 291 goto err_rtc; 292 293 if (ret & DA9055_RTC_ALM_EN) 294 rtc->alarm_enable = 1; 295 296 device_init_wakeup(&pdev->dev, 1); 297 298 rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, 299 &da9055_rtc_ops, THIS_MODULE); 300 if (IS_ERR(rtc->rtc)) { 301 ret = PTR_ERR(rtc->rtc); 302 goto err_rtc; 303 } 304 305 alm_irq = platform_get_irq_byname(pdev, "ALM"); 306 if (alm_irq < 0) 307 return alm_irq; 308 309 ret = devm_request_threaded_irq(&pdev->dev, alm_irq, NULL, 310 da9055_rtc_alm_irq, 311 IRQF_TRIGGER_HIGH | IRQF_ONESHOT, 312 "ALM", rtc); 313 if (ret != 0) 314 dev_err(rtc->da9055->dev, "irq registration failed: %d\n", ret); 315 316 err_rtc: 317 return ret; 318 319 } 320 321 #ifdef CONFIG_PM 322 /* Turn off the alarm if it should not be a wake source. */ 323 static int da9055_rtc_suspend(struct device *dev) 324 { 325 struct platform_device *pdev = to_platform_device(dev); 326 struct da9055_rtc *rtc = dev_get_drvdata(&pdev->dev); 327 int ret; 328 329 if (!device_may_wakeup(&pdev->dev)) { 330 /* Disable the ALM IRQ */ 331 ret = da9055_rtc_enable_alarm(rtc, 0); 332 if (ret < 0) 333 dev_err(&pdev->dev, "Failed to disable RTC ALM\n"); 334 } 335 336 return 0; 337 } 338 339 /* Enable the alarm if it should be enabled (in case it was disabled to 340 * prevent use as a wake source). 341 */ 342 static int da9055_rtc_resume(struct device *dev) 343 { 344 struct platform_device *pdev = to_platform_device(dev); 345 struct da9055_rtc *rtc = dev_get_drvdata(&pdev->dev); 346 int ret; 347 348 if (!device_may_wakeup(&pdev->dev)) { 349 if (rtc->alarm_enable) { 350 ret = da9055_rtc_enable_alarm(rtc, 1); 351 if (ret < 0) 352 dev_err(&pdev->dev, 353 "Failed to restart RTC ALM\n"); 354 } 355 } 356 357 return 0; 358 } 359 360 /* Unconditionally disable the alarm */ 361 static int da9055_rtc_freeze(struct device *dev) 362 { 363 struct platform_device *pdev = to_platform_device(dev); 364 struct da9055_rtc *rtc = dev_get_drvdata(&pdev->dev); 365 int ret; 366 367 ret = da9055_rtc_enable_alarm(rtc, 0); 368 if (ret < 0) 369 dev_err(&pdev->dev, "Failed to freeze RTC ALMs\n"); 370 371 return 0; 372 373 } 374 #else 375 #define da9055_rtc_suspend NULL 376 #define da9055_rtc_resume NULL 377 #define da9055_rtc_freeze NULL 378 #endif 379 380 static const struct dev_pm_ops da9055_rtc_pm_ops = { 381 .suspend = da9055_rtc_suspend, 382 .resume = da9055_rtc_resume, 383 384 .freeze = da9055_rtc_freeze, 385 .thaw = da9055_rtc_resume, 386 .restore = da9055_rtc_resume, 387 388 .poweroff = da9055_rtc_suspend, 389 }; 390 391 static struct platform_driver da9055_rtc_driver = { 392 .probe = da9055_rtc_probe, 393 .driver = { 394 .name = "da9055-rtc", 395 .pm = &da9055_rtc_pm_ops, 396 }, 397 }; 398 399 module_platform_driver(da9055_rtc_driver); 400 401 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>"); 402 MODULE_DESCRIPTION("RTC driver for Dialog DA9055 PMIC"); 403 MODULE_LICENSE("GPL"); 404 MODULE_ALIAS("platform:da9055-rtc"); 405