1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Real time clock driver for DA9055 4 * 5 * Copyright(c) 2012 Dialog Semiconductor Ltd. 6 * 7 * Author: Dajun Dajun Chen <dajun.chen@diasemi.com> 8 */ 9 10 #include <linux/module.h> 11 #include <linux/platform_device.h> 12 #include <linux/rtc.h> 13 14 #include <linux/mfd/da9055/core.h> 15 #include <linux/mfd/da9055/reg.h> 16 #include <linux/mfd/da9055/pdata.h> 17 18 struct da9055_rtc { 19 struct rtc_device *rtc; 20 struct da9055 *da9055; 21 int alarm_enable; 22 }; 23 24 static int da9055_rtc_enable_alarm(struct da9055_rtc *rtc, bool enable) 25 { 26 int ret; 27 if (enable) { 28 ret = da9055_reg_update(rtc->da9055, DA9055_REG_ALARM_Y, 29 DA9055_RTC_ALM_EN, 30 DA9055_RTC_ALM_EN); 31 if (ret != 0) 32 dev_err(rtc->da9055->dev, "Failed to enable ALM: %d\n", 33 ret); 34 rtc->alarm_enable = 1; 35 } else { 36 ret = da9055_reg_update(rtc->da9055, DA9055_REG_ALARM_Y, 37 DA9055_RTC_ALM_EN, 0); 38 if (ret != 0) 39 dev_err(rtc->da9055->dev, 40 "Failed to disable ALM: %d\n", ret); 41 rtc->alarm_enable = 0; 42 } 43 return ret; 44 } 45 46 static irqreturn_t da9055_rtc_alm_irq(int irq, void *data) 47 { 48 struct da9055_rtc *rtc = data; 49 50 da9055_rtc_enable_alarm(rtc, 0); 51 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF); 52 53 return IRQ_HANDLED; 54 } 55 56 static int da9055_read_alarm(struct da9055 *da9055, struct rtc_time *rtc_tm) 57 { 58 int ret; 59 uint8_t v[5]; 60 61 ret = da9055_group_read(da9055, DA9055_REG_ALARM_MI, 5, v); 62 if (ret != 0) { 63 dev_err(da9055->dev, "Failed to group read ALM: %d\n", ret); 64 return ret; 65 } 66 67 rtc_tm->tm_year = (v[4] & DA9055_RTC_ALM_YEAR) + 100; 68 rtc_tm->tm_mon = (v[3] & DA9055_RTC_ALM_MONTH) - 1; 69 rtc_tm->tm_mday = v[2] & DA9055_RTC_ALM_DAY; 70 rtc_tm->tm_hour = v[1] & DA9055_RTC_ALM_HOUR; 71 rtc_tm->tm_min = v[0] & DA9055_RTC_ALM_MIN; 72 rtc_tm->tm_sec = 0; 73 74 return rtc_valid_tm(rtc_tm); 75 } 76 77 static int da9055_set_alarm(struct da9055 *da9055, struct rtc_time *rtc_tm) 78 { 79 int ret; 80 uint8_t v[2]; 81 82 rtc_tm->tm_year -= 100; 83 rtc_tm->tm_mon += 1; 84 85 ret = da9055_reg_update(da9055, DA9055_REG_ALARM_MI, 86 DA9055_RTC_ALM_MIN, rtc_tm->tm_min); 87 if (ret != 0) { 88 dev_err(da9055->dev, "Failed to write ALRM MIN: %d\n", ret); 89 return ret; 90 } 91 92 v[0] = rtc_tm->tm_hour; 93 v[1] = rtc_tm->tm_mday; 94 95 ret = da9055_group_write(da9055, DA9055_REG_ALARM_H, 2, v); 96 if (ret < 0) 97 return ret; 98 99 ret = da9055_reg_update(da9055, DA9055_REG_ALARM_MO, 100 DA9055_RTC_ALM_MONTH, rtc_tm->tm_mon); 101 if (ret < 0) 102 dev_err(da9055->dev, "Failed to write ALM Month:%d\n", ret); 103 104 ret = da9055_reg_update(da9055, DA9055_REG_ALARM_Y, 105 DA9055_RTC_ALM_YEAR, rtc_tm->tm_year); 106 if (ret < 0) 107 dev_err(da9055->dev, "Failed to write ALM Year:%d\n", ret); 108 109 return ret; 110 } 111 112 static int da9055_rtc_get_alarm_status(struct da9055 *da9055) 113 { 114 int ret; 115 116 ret = da9055_reg_read(da9055, DA9055_REG_ALARM_Y); 117 if (ret < 0) { 118 dev_err(da9055->dev, "Failed to read ALM: %d\n", ret); 119 return ret; 120 } 121 ret &= DA9055_RTC_ALM_EN; 122 return (ret > 0) ? 1 : 0; 123 } 124 125 static int da9055_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm) 126 { 127 struct da9055_rtc *rtc = dev_get_drvdata(dev); 128 uint8_t v[6]; 129 int ret; 130 131 ret = da9055_reg_read(rtc->da9055, DA9055_REG_COUNT_S); 132 if (ret < 0) 133 return ret; 134 135 /* 136 * Registers are only valid when RTC_READ 137 * status bit is asserted 138 */ 139 if (!(ret & DA9055_RTC_READ)) 140 return -EBUSY; 141 142 ret = da9055_group_read(rtc->da9055, DA9055_REG_COUNT_S, 6, v); 143 if (ret < 0) { 144 dev_err(rtc->da9055->dev, "Failed to read RTC time : %d\n", 145 ret); 146 return ret; 147 } 148 149 rtc_tm->tm_year = (v[5] & DA9055_RTC_YEAR) + 100; 150 rtc_tm->tm_mon = (v[4] & DA9055_RTC_MONTH) - 1; 151 rtc_tm->tm_mday = v[3] & DA9055_RTC_DAY; 152 rtc_tm->tm_hour = v[2] & DA9055_RTC_HOUR; 153 rtc_tm->tm_min = v[1] & DA9055_RTC_MIN; 154 rtc_tm->tm_sec = v[0] & DA9055_RTC_SEC; 155 156 return 0; 157 } 158 159 static int da9055_rtc_set_time(struct device *dev, struct rtc_time *tm) 160 { 161 struct da9055_rtc *rtc; 162 uint8_t v[6]; 163 164 rtc = dev_get_drvdata(dev); 165 166 v[0] = tm->tm_sec; 167 v[1] = tm->tm_min; 168 v[2] = tm->tm_hour; 169 v[3] = tm->tm_mday; 170 v[4] = tm->tm_mon + 1; 171 v[5] = tm->tm_year - 100; 172 173 return da9055_group_write(rtc->da9055, DA9055_REG_COUNT_S, 6, v); 174 } 175 176 static int da9055_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) 177 { 178 int ret; 179 struct rtc_time *tm = &alrm->time; 180 struct da9055_rtc *rtc = dev_get_drvdata(dev); 181 182 ret = da9055_read_alarm(rtc->da9055, tm); 183 184 if (ret) 185 return ret; 186 187 alrm->enabled = da9055_rtc_get_alarm_status(rtc->da9055); 188 189 return 0; 190 } 191 192 static int da9055_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) 193 { 194 int ret; 195 struct rtc_time *tm = &alrm->time; 196 struct da9055_rtc *rtc = dev_get_drvdata(dev); 197 198 ret = da9055_rtc_enable_alarm(rtc, 0); 199 if (ret < 0) 200 return ret; 201 202 ret = da9055_set_alarm(rtc->da9055, tm); 203 if (ret) 204 return ret; 205 206 ret = da9055_rtc_enable_alarm(rtc, 1); 207 208 return ret; 209 } 210 211 static int da9055_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) 212 { 213 struct da9055_rtc *rtc = dev_get_drvdata(dev); 214 215 return da9055_rtc_enable_alarm(rtc, enabled); 216 } 217 218 static const struct rtc_class_ops da9055_rtc_ops = { 219 .read_time = da9055_rtc_read_time, 220 .set_time = da9055_rtc_set_time, 221 .read_alarm = da9055_rtc_read_alarm, 222 .set_alarm = da9055_rtc_set_alarm, 223 .alarm_irq_enable = da9055_rtc_alarm_irq_enable, 224 }; 225 226 static int da9055_rtc_device_init(struct da9055 *da9055, 227 struct da9055_pdata *pdata) 228 { 229 int ret; 230 231 /* Enable RTC and the internal Crystal */ 232 ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B, 233 DA9055_RTC_EN, DA9055_RTC_EN); 234 if (ret < 0) 235 return ret; 236 ret = da9055_reg_update(da9055, DA9055_REG_EN_32K, 237 DA9055_CRYSTAL_EN, DA9055_CRYSTAL_EN); 238 if (ret < 0) 239 return ret; 240 241 /* Enable RTC in Power Down mode */ 242 ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B, 243 DA9055_RTC_MODE_PD, DA9055_RTC_MODE_PD); 244 if (ret < 0) 245 return ret; 246 247 /* Enable RTC in Reset mode */ 248 if (pdata && pdata->reset_enable) { 249 ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B, 250 DA9055_RTC_MODE_SD, 251 DA9055_RTC_MODE_SD << 252 DA9055_RTC_MODE_SD_SHIFT); 253 if (ret < 0) 254 return ret; 255 } 256 257 /* Disable the RTC TICK ALM */ 258 ret = da9055_reg_update(da9055, DA9055_REG_ALARM_MO, 259 DA9055_RTC_TICK_WAKE_MASK, 0); 260 if (ret < 0) 261 return ret; 262 263 return 0; 264 } 265 266 static int da9055_rtc_probe(struct platform_device *pdev) 267 { 268 struct da9055_rtc *rtc; 269 struct da9055_pdata *pdata = NULL; 270 int ret, alm_irq; 271 272 rtc = devm_kzalloc(&pdev->dev, sizeof(struct da9055_rtc), GFP_KERNEL); 273 if (!rtc) 274 return -ENOMEM; 275 276 rtc->da9055 = dev_get_drvdata(pdev->dev.parent); 277 pdata = dev_get_platdata(rtc->da9055->dev); 278 platform_set_drvdata(pdev, rtc); 279 280 ret = da9055_rtc_device_init(rtc->da9055, pdata); 281 if (ret < 0) 282 goto err_rtc; 283 284 ret = da9055_reg_read(rtc->da9055, DA9055_REG_ALARM_Y); 285 if (ret < 0) 286 goto err_rtc; 287 288 if (ret & DA9055_RTC_ALM_EN) 289 rtc->alarm_enable = 1; 290 291 device_init_wakeup(&pdev->dev, 1); 292 293 rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, 294 &da9055_rtc_ops, THIS_MODULE); 295 if (IS_ERR(rtc->rtc)) { 296 ret = PTR_ERR(rtc->rtc); 297 goto err_rtc; 298 } 299 300 alm_irq = platform_get_irq_byname(pdev, "ALM"); 301 if (alm_irq < 0) 302 return alm_irq; 303 304 ret = devm_request_threaded_irq(&pdev->dev, alm_irq, NULL, 305 da9055_rtc_alm_irq, 306 IRQF_TRIGGER_HIGH | IRQF_ONESHOT, 307 "ALM", rtc); 308 if (ret != 0) 309 dev_err(rtc->da9055->dev, "irq registration failed: %d\n", ret); 310 311 err_rtc: 312 return ret; 313 314 } 315 316 #ifdef CONFIG_PM 317 /* Turn off the alarm if it should not be a wake source. */ 318 static int da9055_rtc_suspend(struct device *dev) 319 { 320 struct platform_device *pdev = to_platform_device(dev); 321 struct da9055_rtc *rtc = dev_get_drvdata(&pdev->dev); 322 int ret; 323 324 if (!device_may_wakeup(&pdev->dev)) { 325 /* Disable the ALM IRQ */ 326 ret = da9055_rtc_enable_alarm(rtc, 0); 327 if (ret < 0) 328 dev_err(&pdev->dev, "Failed to disable RTC ALM\n"); 329 } 330 331 return 0; 332 } 333 334 /* Enable the alarm if it should be enabled (in case it was disabled to 335 * prevent use as a wake source). 336 */ 337 static int da9055_rtc_resume(struct device *dev) 338 { 339 struct platform_device *pdev = to_platform_device(dev); 340 struct da9055_rtc *rtc = dev_get_drvdata(&pdev->dev); 341 int ret; 342 343 if (!device_may_wakeup(&pdev->dev)) { 344 if (rtc->alarm_enable) { 345 ret = da9055_rtc_enable_alarm(rtc, 1); 346 if (ret < 0) 347 dev_err(&pdev->dev, 348 "Failed to restart RTC ALM\n"); 349 } 350 } 351 352 return 0; 353 } 354 355 /* Unconditionally disable the alarm */ 356 static int da9055_rtc_freeze(struct device *dev) 357 { 358 struct platform_device *pdev = to_platform_device(dev); 359 struct da9055_rtc *rtc = dev_get_drvdata(&pdev->dev); 360 int ret; 361 362 ret = da9055_rtc_enable_alarm(rtc, 0); 363 if (ret < 0) 364 dev_err(&pdev->dev, "Failed to freeze RTC ALMs\n"); 365 366 return 0; 367 368 } 369 #else 370 #define da9055_rtc_suspend NULL 371 #define da9055_rtc_resume NULL 372 #define da9055_rtc_freeze NULL 373 #endif 374 375 static const struct dev_pm_ops da9055_rtc_pm_ops = { 376 .suspend = da9055_rtc_suspend, 377 .resume = da9055_rtc_resume, 378 379 .freeze = da9055_rtc_freeze, 380 .thaw = da9055_rtc_resume, 381 .restore = da9055_rtc_resume, 382 383 .poweroff = da9055_rtc_suspend, 384 }; 385 386 static struct platform_driver da9055_rtc_driver = { 387 .probe = da9055_rtc_probe, 388 .driver = { 389 .name = "da9055-rtc", 390 .pm = &da9055_rtc_pm_ops, 391 }, 392 }; 393 394 module_platform_driver(da9055_rtc_driver); 395 396 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>"); 397 MODULE_DESCRIPTION("RTC driver for Dialog DA9055 PMIC"); 398 MODULE_LICENSE("GPL"); 399 MODULE_ALIAS("platform:da9055-rtc"); 400