1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Real-time clock driver for MPC5121 4 * 5 * Copyright 2007, Domen Puncer <domen.puncer@telargo.com> 6 * Copyright 2008, Freescale Semiconductor, Inc. All rights reserved. 7 * Copyright 2011, Dmitry Eremin-Solenikov 8 */ 9 10 #include <linux/init.h> 11 #include <linux/module.h> 12 #include <linux/rtc.h> 13 #include <linux/of.h> 14 #include <linux/of_address.h> 15 #include <linux/of_device.h> 16 #include <linux/of_irq.h> 17 #include <linux/of_platform.h> 18 #include <linux/io.h> 19 #include <linux/slab.h> 20 21 struct mpc5121_rtc_regs { 22 u8 set_time; /* RTC + 0x00 */ 23 u8 hour_set; /* RTC + 0x01 */ 24 u8 minute_set; /* RTC + 0x02 */ 25 u8 second_set; /* RTC + 0x03 */ 26 27 u8 set_date; /* RTC + 0x04 */ 28 u8 month_set; /* RTC + 0x05 */ 29 u8 weekday_set; /* RTC + 0x06 */ 30 u8 date_set; /* RTC + 0x07 */ 31 32 u8 write_sw; /* RTC + 0x08 */ 33 u8 sw_set; /* RTC + 0x09 */ 34 u16 year_set; /* RTC + 0x0a */ 35 36 u8 alm_enable; /* RTC + 0x0c */ 37 u8 alm_hour_set; /* RTC + 0x0d */ 38 u8 alm_min_set; /* RTC + 0x0e */ 39 u8 int_enable; /* RTC + 0x0f */ 40 41 u8 reserved1; 42 u8 hour; /* RTC + 0x11 */ 43 u8 minute; /* RTC + 0x12 */ 44 u8 second; /* RTC + 0x13 */ 45 46 u8 month; /* RTC + 0x14 */ 47 u8 wday_mday; /* RTC + 0x15 */ 48 u16 year; /* RTC + 0x16 */ 49 50 u8 int_alm; /* RTC + 0x18 */ 51 u8 int_sw; /* RTC + 0x19 */ 52 u8 alm_status; /* RTC + 0x1a */ 53 u8 sw_minute; /* RTC + 0x1b */ 54 55 u8 bus_error_1; /* RTC + 0x1c */ 56 u8 int_day; /* RTC + 0x1d */ 57 u8 int_min; /* RTC + 0x1e */ 58 u8 int_sec; /* RTC + 0x1f */ 59 60 /* 61 * target_time: 62 * intended to be used for hibernation but hibernation 63 * does not work on silicon rev 1.5 so use it for non-volatile 64 * storage of offset between the actual_time register and linux 65 * time 66 */ 67 u32 target_time; /* RTC + 0x20 */ 68 /* 69 * actual_time: 70 * readonly time since VBAT_RTC was last connected 71 */ 72 u32 actual_time; /* RTC + 0x24 */ 73 u32 keep_alive; /* RTC + 0x28 */ 74 }; 75 76 struct mpc5121_rtc_data { 77 unsigned irq; 78 unsigned irq_periodic; 79 struct mpc5121_rtc_regs __iomem *regs; 80 struct rtc_device *rtc; 81 struct rtc_wkalrm wkalarm; 82 }; 83 84 /* 85 * Update second/minute/hour registers. 86 * 87 * This is just so alarm will work. 88 */ 89 static void mpc5121_rtc_update_smh(struct mpc5121_rtc_regs __iomem *regs, 90 struct rtc_time *tm) 91 { 92 out_8(®s->second_set, tm->tm_sec); 93 out_8(®s->minute_set, tm->tm_min); 94 out_8(®s->hour_set, tm->tm_hour); 95 96 /* set time sequence */ 97 out_8(®s->set_time, 0x1); 98 out_8(®s->set_time, 0x3); 99 out_8(®s->set_time, 0x1); 100 out_8(®s->set_time, 0x0); 101 } 102 103 static int mpc5121_rtc_read_time(struct device *dev, struct rtc_time *tm) 104 { 105 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 106 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 107 unsigned long now; 108 109 /* 110 * linux time is actual_time plus the offset saved in target_time 111 */ 112 now = in_be32(®s->actual_time) + in_be32(®s->target_time); 113 114 rtc_time_to_tm(now, tm); 115 116 /* 117 * update second minute hour registers 118 * so alarms will work 119 */ 120 mpc5121_rtc_update_smh(regs, tm); 121 122 return 0; 123 } 124 125 static int mpc5121_rtc_set_time(struct device *dev, struct rtc_time *tm) 126 { 127 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 128 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 129 int ret; 130 unsigned long now; 131 132 /* 133 * The actual_time register is read only so we write the offset 134 * between it and linux time to the target_time register. 135 */ 136 ret = rtc_tm_to_time(tm, &now); 137 if (ret == 0) 138 out_be32(®s->target_time, now - in_be32(®s->actual_time)); 139 140 /* 141 * update second minute hour registers 142 * so alarms will work 143 */ 144 mpc5121_rtc_update_smh(regs, tm); 145 146 return 0; 147 } 148 149 static int mpc5200_rtc_read_time(struct device *dev, struct rtc_time *tm) 150 { 151 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 152 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 153 int tmp; 154 155 tm->tm_sec = in_8(®s->second); 156 tm->tm_min = in_8(®s->minute); 157 158 /* 12 hour format? */ 159 if (in_8(®s->hour) & 0x20) 160 tm->tm_hour = (in_8(®s->hour) >> 1) + 161 (in_8(®s->hour) & 1 ? 12 : 0); 162 else 163 tm->tm_hour = in_8(®s->hour); 164 165 tmp = in_8(®s->wday_mday); 166 tm->tm_mday = tmp & 0x1f; 167 tm->tm_mon = in_8(®s->month) - 1; 168 tm->tm_year = in_be16(®s->year) - 1900; 169 tm->tm_wday = (tmp >> 5) % 7; 170 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); 171 tm->tm_isdst = 0; 172 173 return 0; 174 } 175 176 static int mpc5200_rtc_set_time(struct device *dev, struct rtc_time *tm) 177 { 178 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 179 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 180 181 mpc5121_rtc_update_smh(regs, tm); 182 183 /* date */ 184 out_8(®s->month_set, tm->tm_mon + 1); 185 out_8(®s->weekday_set, tm->tm_wday ? tm->tm_wday : 7); 186 out_8(®s->date_set, tm->tm_mday); 187 out_be16(®s->year_set, tm->tm_year + 1900); 188 189 /* set date sequence */ 190 out_8(®s->set_date, 0x1); 191 out_8(®s->set_date, 0x3); 192 out_8(®s->set_date, 0x1); 193 out_8(®s->set_date, 0x0); 194 195 return 0; 196 } 197 198 static int mpc5121_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) 199 { 200 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 201 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 202 203 *alarm = rtc->wkalarm; 204 205 alarm->pending = in_8(®s->alm_status); 206 207 return 0; 208 } 209 210 static int mpc5121_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) 211 { 212 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 213 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 214 215 /* 216 * the alarm has no seconds so deal with it 217 */ 218 if (alarm->time.tm_sec) { 219 alarm->time.tm_sec = 0; 220 alarm->time.tm_min++; 221 if (alarm->time.tm_min >= 60) { 222 alarm->time.tm_min = 0; 223 alarm->time.tm_hour++; 224 if (alarm->time.tm_hour >= 24) 225 alarm->time.tm_hour = 0; 226 } 227 } 228 229 alarm->time.tm_mday = -1; 230 alarm->time.tm_mon = -1; 231 alarm->time.tm_year = -1; 232 233 out_8(®s->alm_min_set, alarm->time.tm_min); 234 out_8(®s->alm_hour_set, alarm->time.tm_hour); 235 236 out_8(®s->alm_enable, alarm->enabled); 237 238 rtc->wkalarm = *alarm; 239 return 0; 240 } 241 242 static irqreturn_t mpc5121_rtc_handler(int irq, void *dev) 243 { 244 struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev); 245 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 246 247 if (in_8(®s->int_alm)) { 248 /* acknowledge and clear status */ 249 out_8(®s->int_alm, 1); 250 out_8(®s->alm_status, 1); 251 252 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF); 253 return IRQ_HANDLED; 254 } 255 256 return IRQ_NONE; 257 } 258 259 static irqreturn_t mpc5121_rtc_handler_upd(int irq, void *dev) 260 { 261 struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev); 262 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 263 264 if (in_8(®s->int_sec) && (in_8(®s->int_enable) & 0x1)) { 265 /* acknowledge */ 266 out_8(®s->int_sec, 1); 267 268 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_UF); 269 return IRQ_HANDLED; 270 } 271 272 return IRQ_NONE; 273 } 274 275 static int mpc5121_rtc_alarm_irq_enable(struct device *dev, 276 unsigned int enabled) 277 { 278 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 279 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 280 int val; 281 282 if (enabled) 283 val = 1; 284 else 285 val = 0; 286 287 out_8(®s->alm_enable, val); 288 rtc->wkalarm.enabled = val; 289 290 return 0; 291 } 292 293 static const struct rtc_class_ops mpc5121_rtc_ops = { 294 .read_time = mpc5121_rtc_read_time, 295 .set_time = mpc5121_rtc_set_time, 296 .read_alarm = mpc5121_rtc_read_alarm, 297 .set_alarm = mpc5121_rtc_set_alarm, 298 .alarm_irq_enable = mpc5121_rtc_alarm_irq_enable, 299 }; 300 301 static const struct rtc_class_ops mpc5200_rtc_ops = { 302 .read_time = mpc5200_rtc_read_time, 303 .set_time = mpc5200_rtc_set_time, 304 .read_alarm = mpc5121_rtc_read_alarm, 305 .set_alarm = mpc5121_rtc_set_alarm, 306 .alarm_irq_enable = mpc5121_rtc_alarm_irq_enable, 307 }; 308 309 static int mpc5121_rtc_probe(struct platform_device *op) 310 { 311 struct mpc5121_rtc_data *rtc; 312 int err = 0; 313 314 rtc = devm_kzalloc(&op->dev, sizeof(*rtc), GFP_KERNEL); 315 if (!rtc) 316 return -ENOMEM; 317 318 rtc->regs = of_iomap(op->dev.of_node, 0); 319 if (!rtc->regs) { 320 dev_err(&op->dev, "%s: couldn't map io space\n", __func__); 321 return -ENOSYS; 322 } 323 324 device_init_wakeup(&op->dev, 1); 325 326 platform_set_drvdata(op, rtc); 327 328 rtc->irq = irq_of_parse_and_map(op->dev.of_node, 1); 329 err = request_irq(rtc->irq, mpc5121_rtc_handler, 0, 330 "mpc5121-rtc", &op->dev); 331 if (err) { 332 dev_err(&op->dev, "%s: could not request irq: %i\n", 333 __func__, rtc->irq); 334 goto out_dispose; 335 } 336 337 rtc->irq_periodic = irq_of_parse_and_map(op->dev.of_node, 0); 338 err = request_irq(rtc->irq_periodic, mpc5121_rtc_handler_upd, 339 0, "mpc5121-rtc_upd", &op->dev); 340 if (err) { 341 dev_err(&op->dev, "%s: could not request irq: %i\n", 342 __func__, rtc->irq_periodic); 343 goto out_dispose2; 344 } 345 346 if (of_device_is_compatible(op->dev.of_node, "fsl,mpc5121-rtc")) { 347 u32 ka; 348 ka = in_be32(&rtc->regs->keep_alive); 349 if (ka & 0x02) { 350 dev_warn(&op->dev, 351 "mpc5121-rtc: Battery or oscillator failure!\n"); 352 out_be32(&rtc->regs->keep_alive, ka); 353 } 354 355 rtc->rtc = devm_rtc_device_register(&op->dev, "mpc5121-rtc", 356 &mpc5121_rtc_ops, THIS_MODULE); 357 } else { 358 rtc->rtc = devm_rtc_device_register(&op->dev, "mpc5200-rtc", 359 &mpc5200_rtc_ops, THIS_MODULE); 360 } 361 362 if (IS_ERR(rtc->rtc)) { 363 err = PTR_ERR(rtc->rtc); 364 goto out_free_irq; 365 } 366 rtc->rtc->uie_unsupported = 1; 367 368 return 0; 369 370 out_free_irq: 371 free_irq(rtc->irq_periodic, &op->dev); 372 out_dispose2: 373 irq_dispose_mapping(rtc->irq_periodic); 374 free_irq(rtc->irq, &op->dev); 375 out_dispose: 376 irq_dispose_mapping(rtc->irq); 377 iounmap(rtc->regs); 378 379 return err; 380 } 381 382 static int mpc5121_rtc_remove(struct platform_device *op) 383 { 384 struct mpc5121_rtc_data *rtc = platform_get_drvdata(op); 385 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 386 387 /* disable interrupt, so there are no nasty surprises */ 388 out_8(®s->alm_enable, 0); 389 out_8(®s->int_enable, in_8(®s->int_enable) & ~0x1); 390 391 iounmap(rtc->regs); 392 free_irq(rtc->irq, &op->dev); 393 free_irq(rtc->irq_periodic, &op->dev); 394 irq_dispose_mapping(rtc->irq); 395 irq_dispose_mapping(rtc->irq_periodic); 396 397 return 0; 398 } 399 400 #ifdef CONFIG_OF 401 static const struct of_device_id mpc5121_rtc_match[] = { 402 { .compatible = "fsl,mpc5121-rtc", }, 403 { .compatible = "fsl,mpc5200-rtc", }, 404 {}, 405 }; 406 MODULE_DEVICE_TABLE(of, mpc5121_rtc_match); 407 #endif 408 409 static struct platform_driver mpc5121_rtc_driver = { 410 .driver = { 411 .name = "mpc5121-rtc", 412 .of_match_table = of_match_ptr(mpc5121_rtc_match), 413 }, 414 .probe = mpc5121_rtc_probe, 415 .remove = mpc5121_rtc_remove, 416 }; 417 418 module_platform_driver(mpc5121_rtc_driver); 419 420 MODULE_LICENSE("GPL"); 421 MODULE_AUTHOR("John Rigby <jcrigby@gmail.com>"); 422