1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2014-2015 MediaTek Inc. 4 * Author: Tianping.Fang <tianping.fang@mediatek.com> 5 */ 6 7 #include <linux/err.h> 8 #include <linux/interrupt.h> 9 #include <linux/mfd/mt6397/core.h> 10 #include <linux/module.h> 11 #include <linux/mutex.h> 12 #include <linux/of_device.h> 13 #include <linux/platform_device.h> 14 #include <linux/regmap.h> 15 #include <linux/rtc.h> 16 #include <linux/mfd/mt6397/rtc.h> 17 #include <linux/mod_devicetable.h> 18 19 static int mtk_rtc_write_trigger(struct mt6397_rtc *rtc) 20 { 21 int ret; 22 u32 data; 23 24 ret = regmap_write(rtc->regmap, rtc->addr_base + rtc->data->wrtgr, 1); 25 if (ret < 0) 26 return ret; 27 28 ret = regmap_read_poll_timeout(rtc->regmap, 29 rtc->addr_base + RTC_BBPU, data, 30 !(data & RTC_BBPU_CBUSY), 31 MTK_RTC_POLL_DELAY_US, 32 MTK_RTC_POLL_TIMEOUT); 33 if (ret < 0) 34 dev_err(rtc->rtc_dev->dev.parent, 35 "failed to write WRTGR: %d\n", ret); 36 37 return ret; 38 } 39 40 static irqreturn_t mtk_rtc_irq_handler_thread(int irq, void *data) 41 { 42 struct mt6397_rtc *rtc = data; 43 u32 irqsta, irqen; 44 int ret; 45 46 ret = regmap_read(rtc->regmap, rtc->addr_base + RTC_IRQ_STA, &irqsta); 47 if ((ret >= 0) && (irqsta & RTC_IRQ_STA_AL)) { 48 rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF); 49 irqen = irqsta & ~RTC_IRQ_EN_AL; 50 mutex_lock(&rtc->lock); 51 if (regmap_write(rtc->regmap, rtc->addr_base + RTC_IRQ_EN, 52 irqen) == 0) 53 mtk_rtc_write_trigger(rtc); 54 mutex_unlock(&rtc->lock); 55 56 return IRQ_HANDLED; 57 } 58 59 return IRQ_NONE; 60 } 61 62 static int __mtk_rtc_read_time(struct mt6397_rtc *rtc, 63 struct rtc_time *tm, int *sec) 64 { 65 int ret; 66 u16 data[RTC_OFFSET_COUNT]; 67 68 mutex_lock(&rtc->lock); 69 ret = regmap_bulk_read(rtc->regmap, rtc->addr_base + RTC_TC_SEC, 70 data, RTC_OFFSET_COUNT); 71 if (ret < 0) 72 goto exit; 73 74 tm->tm_sec = data[RTC_OFFSET_SEC]; 75 tm->tm_min = data[RTC_OFFSET_MIN]; 76 tm->tm_hour = data[RTC_OFFSET_HOUR]; 77 tm->tm_mday = data[RTC_OFFSET_DOM]; 78 tm->tm_mon = data[RTC_OFFSET_MTH] & RTC_TC_MTH_MASK; 79 tm->tm_year = data[RTC_OFFSET_YEAR]; 80 81 ret = regmap_read(rtc->regmap, rtc->addr_base + RTC_TC_SEC, sec); 82 exit: 83 mutex_unlock(&rtc->lock); 84 return ret; 85 } 86 87 static int mtk_rtc_read_time(struct device *dev, struct rtc_time *tm) 88 { 89 time64_t time; 90 struct mt6397_rtc *rtc = dev_get_drvdata(dev); 91 int days, sec, ret; 92 93 do { 94 ret = __mtk_rtc_read_time(rtc, tm, &sec); 95 if (ret < 0) 96 goto exit; 97 } while (sec < tm->tm_sec); 98 99 /* HW register use 7 bits to store year data, minus 100 * RTC_MIN_YEAR_OFFSET before write year data to register, and plus 101 * RTC_MIN_YEAR_OFFSET back after read year from register 102 */ 103 tm->tm_year += RTC_MIN_YEAR_OFFSET; 104 105 /* HW register start mon from one, but tm_mon start from zero. */ 106 tm->tm_mon--; 107 time = rtc_tm_to_time64(tm); 108 109 /* rtc_tm_to_time64 covert Gregorian date to seconds since 110 * 01-01-1970 00:00:00, and this date is Thursday. 111 */ 112 days = div_s64(time, 86400); 113 tm->tm_wday = (days + 4) % 7; 114 115 exit: 116 return ret; 117 } 118 119 static int mtk_rtc_set_time(struct device *dev, struct rtc_time *tm) 120 { 121 struct mt6397_rtc *rtc = dev_get_drvdata(dev); 122 int ret; 123 u16 data[RTC_OFFSET_COUNT]; 124 125 tm->tm_year -= RTC_MIN_YEAR_OFFSET; 126 tm->tm_mon++; 127 128 data[RTC_OFFSET_SEC] = tm->tm_sec; 129 data[RTC_OFFSET_MIN] = tm->tm_min; 130 data[RTC_OFFSET_HOUR] = tm->tm_hour; 131 data[RTC_OFFSET_DOM] = tm->tm_mday; 132 data[RTC_OFFSET_MTH] = tm->tm_mon; 133 data[RTC_OFFSET_YEAR] = tm->tm_year; 134 135 mutex_lock(&rtc->lock); 136 ret = regmap_bulk_write(rtc->regmap, rtc->addr_base + RTC_TC_SEC, 137 data, RTC_OFFSET_COUNT); 138 if (ret < 0) 139 goto exit; 140 141 /* Time register write to hardware after call trigger function */ 142 ret = mtk_rtc_write_trigger(rtc); 143 144 exit: 145 mutex_unlock(&rtc->lock); 146 return ret; 147 } 148 149 static int mtk_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) 150 { 151 struct rtc_time *tm = &alm->time; 152 struct mt6397_rtc *rtc = dev_get_drvdata(dev); 153 u32 irqen, pdn2; 154 int ret; 155 u16 data[RTC_OFFSET_COUNT]; 156 157 mutex_lock(&rtc->lock); 158 ret = regmap_read(rtc->regmap, rtc->addr_base + RTC_IRQ_EN, &irqen); 159 if (ret < 0) 160 goto err_exit; 161 ret = regmap_read(rtc->regmap, rtc->addr_base + RTC_PDN2, &pdn2); 162 if (ret < 0) 163 goto err_exit; 164 165 ret = regmap_bulk_read(rtc->regmap, rtc->addr_base + RTC_AL_SEC, 166 data, RTC_OFFSET_COUNT); 167 if (ret < 0) 168 goto err_exit; 169 170 alm->enabled = !!(irqen & RTC_IRQ_EN_AL); 171 alm->pending = !!(pdn2 & RTC_PDN2_PWRON_ALARM); 172 mutex_unlock(&rtc->lock); 173 174 tm->tm_sec = data[RTC_OFFSET_SEC] & RTC_AL_SEC_MASK; 175 tm->tm_min = data[RTC_OFFSET_MIN] & RTC_AL_MIN_MASK; 176 tm->tm_hour = data[RTC_OFFSET_HOUR] & RTC_AL_HOU_MASK; 177 tm->tm_mday = data[RTC_OFFSET_DOM] & RTC_AL_DOM_MASK; 178 tm->tm_mon = data[RTC_OFFSET_MTH] & RTC_AL_MTH_MASK; 179 tm->tm_year = data[RTC_OFFSET_YEAR] & RTC_AL_YEA_MASK; 180 181 tm->tm_year += RTC_MIN_YEAR_OFFSET; 182 tm->tm_mon--; 183 184 return 0; 185 err_exit: 186 mutex_unlock(&rtc->lock); 187 return ret; 188 } 189 190 static int mtk_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) 191 { 192 struct rtc_time *tm = &alm->time; 193 struct mt6397_rtc *rtc = dev_get_drvdata(dev); 194 int ret; 195 u16 data[RTC_OFFSET_COUNT]; 196 197 tm->tm_year -= RTC_MIN_YEAR_OFFSET; 198 tm->tm_mon++; 199 200 mutex_lock(&rtc->lock); 201 ret = regmap_bulk_read(rtc->regmap, rtc->addr_base + RTC_AL_SEC, 202 data, RTC_OFFSET_COUNT); 203 if (ret < 0) 204 goto exit; 205 206 data[RTC_OFFSET_SEC] = ((data[RTC_OFFSET_SEC] & ~(RTC_AL_SEC_MASK)) | 207 (tm->tm_sec & RTC_AL_SEC_MASK)); 208 data[RTC_OFFSET_MIN] = ((data[RTC_OFFSET_MIN] & ~(RTC_AL_MIN_MASK)) | 209 (tm->tm_min & RTC_AL_MIN_MASK)); 210 data[RTC_OFFSET_HOUR] = ((data[RTC_OFFSET_HOUR] & ~(RTC_AL_HOU_MASK)) | 211 (tm->tm_hour & RTC_AL_HOU_MASK)); 212 data[RTC_OFFSET_DOM] = ((data[RTC_OFFSET_DOM] & ~(RTC_AL_DOM_MASK)) | 213 (tm->tm_mday & RTC_AL_DOM_MASK)); 214 data[RTC_OFFSET_MTH] = ((data[RTC_OFFSET_MTH] & ~(RTC_AL_MTH_MASK)) | 215 (tm->tm_mon & RTC_AL_MTH_MASK)); 216 data[RTC_OFFSET_YEAR] = ((data[RTC_OFFSET_YEAR] & ~(RTC_AL_YEA_MASK)) | 217 (tm->tm_year & RTC_AL_YEA_MASK)); 218 219 if (alm->enabled) { 220 ret = regmap_bulk_write(rtc->regmap, 221 rtc->addr_base + RTC_AL_SEC, 222 data, RTC_OFFSET_COUNT); 223 if (ret < 0) 224 goto exit; 225 ret = regmap_write(rtc->regmap, rtc->addr_base + RTC_AL_MASK, 226 RTC_AL_MASK_DOW); 227 if (ret < 0) 228 goto exit; 229 ret = regmap_update_bits(rtc->regmap, 230 rtc->addr_base + RTC_IRQ_EN, 231 RTC_IRQ_EN_ONESHOT_AL, 232 RTC_IRQ_EN_ONESHOT_AL); 233 if (ret < 0) 234 goto exit; 235 } else { 236 ret = regmap_update_bits(rtc->regmap, 237 rtc->addr_base + RTC_IRQ_EN, 238 RTC_IRQ_EN_ONESHOT_AL, 0); 239 if (ret < 0) 240 goto exit; 241 } 242 243 /* All alarm time register write to hardware after calling 244 * mtk_rtc_write_trigger. This can avoid race condition if alarm 245 * occur happen during writing alarm time register. 246 */ 247 ret = mtk_rtc_write_trigger(rtc); 248 exit: 249 mutex_unlock(&rtc->lock); 250 return ret; 251 } 252 253 static const struct rtc_class_ops mtk_rtc_ops = { 254 .read_time = mtk_rtc_read_time, 255 .set_time = mtk_rtc_set_time, 256 .read_alarm = mtk_rtc_read_alarm, 257 .set_alarm = mtk_rtc_set_alarm, 258 }; 259 260 static int mtk_rtc_probe(struct platform_device *pdev) 261 { 262 struct resource *res; 263 struct mt6397_chip *mt6397_chip = dev_get_drvdata(pdev->dev.parent); 264 struct mt6397_rtc *rtc; 265 int ret; 266 267 rtc = devm_kzalloc(&pdev->dev, sizeof(struct mt6397_rtc), GFP_KERNEL); 268 if (!rtc) 269 return -ENOMEM; 270 271 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 272 if (!res) 273 return -EINVAL; 274 rtc->addr_base = res->start; 275 276 rtc->data = of_device_get_match_data(&pdev->dev); 277 278 rtc->irq = platform_get_irq(pdev, 0); 279 if (rtc->irq < 0) 280 return rtc->irq; 281 282 rtc->regmap = mt6397_chip->regmap; 283 mutex_init(&rtc->lock); 284 285 platform_set_drvdata(pdev, rtc); 286 287 rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev); 288 if (IS_ERR(rtc->rtc_dev)) 289 return PTR_ERR(rtc->rtc_dev); 290 291 ret = devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL, 292 mtk_rtc_irq_handler_thread, 293 IRQF_ONESHOT | IRQF_TRIGGER_HIGH, 294 "mt6397-rtc", rtc); 295 296 if (ret) { 297 dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n", 298 rtc->irq, ret); 299 return ret; 300 } 301 302 device_init_wakeup(&pdev->dev, 1); 303 304 rtc->rtc_dev->ops = &mtk_rtc_ops; 305 306 return devm_rtc_register_device(rtc->rtc_dev); 307 } 308 309 #ifdef CONFIG_PM_SLEEP 310 static int mt6397_rtc_suspend(struct device *dev) 311 { 312 struct mt6397_rtc *rtc = dev_get_drvdata(dev); 313 314 if (device_may_wakeup(dev)) 315 enable_irq_wake(rtc->irq); 316 317 return 0; 318 } 319 320 static int mt6397_rtc_resume(struct device *dev) 321 { 322 struct mt6397_rtc *rtc = dev_get_drvdata(dev); 323 324 if (device_may_wakeup(dev)) 325 disable_irq_wake(rtc->irq); 326 327 return 0; 328 } 329 #endif 330 331 static SIMPLE_DEV_PM_OPS(mt6397_pm_ops, mt6397_rtc_suspend, 332 mt6397_rtc_resume); 333 334 static const struct mtk_rtc_data mt6358_rtc_data = { 335 .wrtgr = RTC_WRTGR_MT6358, 336 }; 337 338 static const struct mtk_rtc_data mt6397_rtc_data = { 339 .wrtgr = RTC_WRTGR_MT6397, 340 }; 341 342 static const struct of_device_id mt6397_rtc_of_match[] = { 343 { .compatible = "mediatek,mt6323-rtc", .data = &mt6397_rtc_data }, 344 { .compatible = "mediatek,mt6358-rtc", .data = &mt6358_rtc_data }, 345 { .compatible = "mediatek,mt6397-rtc", .data = &mt6397_rtc_data }, 346 { } 347 }; 348 MODULE_DEVICE_TABLE(of, mt6397_rtc_of_match); 349 350 static struct platform_driver mtk_rtc_driver = { 351 .driver = { 352 .name = "mt6397-rtc", 353 .of_match_table = mt6397_rtc_of_match, 354 .pm = &mt6397_pm_ops, 355 }, 356 .probe = mtk_rtc_probe, 357 }; 358 359 module_platform_driver(mtk_rtc_driver); 360 361 MODULE_LICENSE("GPL v2"); 362 MODULE_AUTHOR("Tianping Fang <tianping.fang@mediatek.com>"); 363 MODULE_DESCRIPTION("RTC Driver for MediaTek MT6397 PMIC"); 364