1 /* 2 * Real-time clock driver for MPC5121 3 * 4 * Copyright 2007, Domen Puncer <domen.puncer@telargo.com> 5 * Copyright 2008, Freescale Semiconductor, Inc. All rights reserved. 6 * Copyright 2011, Dmitry Eremin-Solenikov 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 version 2 as 10 * published by the Free Software Foundation. 11 */ 12 13 #include <linux/init.h> 14 #include <linux/module.h> 15 #include <linux/rtc.h> 16 #include <linux/of.h> 17 #include <linux/of_device.h> 18 #include <linux/of_platform.h> 19 #include <linux/io.h> 20 #include <linux/slab.h> 21 22 struct mpc5121_rtc_regs { 23 u8 set_time; /* RTC + 0x00 */ 24 u8 hour_set; /* RTC + 0x01 */ 25 u8 minute_set; /* RTC + 0x02 */ 26 u8 second_set; /* RTC + 0x03 */ 27 28 u8 set_date; /* RTC + 0x04 */ 29 u8 month_set; /* RTC + 0x05 */ 30 u8 weekday_set; /* RTC + 0x06 */ 31 u8 date_set; /* RTC + 0x07 */ 32 33 u8 write_sw; /* RTC + 0x08 */ 34 u8 sw_set; /* RTC + 0x09 */ 35 u16 year_set; /* RTC + 0x0a */ 36 37 u8 alm_enable; /* RTC + 0x0c */ 38 u8 alm_hour_set; /* RTC + 0x0d */ 39 u8 alm_min_set; /* RTC + 0x0e */ 40 u8 int_enable; /* RTC + 0x0f */ 41 42 u8 reserved1; 43 u8 hour; /* RTC + 0x11 */ 44 u8 minute; /* RTC + 0x12 */ 45 u8 second; /* RTC + 0x13 */ 46 47 u8 month; /* RTC + 0x14 */ 48 u8 wday_mday; /* RTC + 0x15 */ 49 u16 year; /* RTC + 0x16 */ 50 51 u8 int_alm; /* RTC + 0x18 */ 52 u8 int_sw; /* RTC + 0x19 */ 53 u8 alm_status; /* RTC + 0x1a */ 54 u8 sw_minute; /* RTC + 0x1b */ 55 56 u8 bus_error_1; /* RTC + 0x1c */ 57 u8 int_day; /* RTC + 0x1d */ 58 u8 int_min; /* RTC + 0x1e */ 59 u8 int_sec; /* RTC + 0x1f */ 60 61 /* 62 * target_time: 63 * intended to be used for hibernation but hibernation 64 * does not work on silicon rev 1.5 so use it for non-volatile 65 * storage of offset between the actual_time register and linux 66 * time 67 */ 68 u32 target_time; /* RTC + 0x20 */ 69 /* 70 * actual_time: 71 * readonly time since VBAT_RTC was last connected 72 */ 73 u32 actual_time; /* RTC + 0x24 */ 74 u32 keep_alive; /* RTC + 0x28 */ 75 }; 76 77 struct mpc5121_rtc_data { 78 unsigned irq; 79 unsigned irq_periodic; 80 struct mpc5121_rtc_regs __iomem *regs; 81 struct rtc_device *rtc; 82 struct rtc_wkalrm wkalarm; 83 }; 84 85 /* 86 * Update second/minute/hour registers. 87 * 88 * This is just so alarm will work. 89 */ 90 static void mpc5121_rtc_update_smh(struct mpc5121_rtc_regs __iomem *regs, 91 struct rtc_time *tm) 92 { 93 out_8(®s->second_set, tm->tm_sec); 94 out_8(®s->minute_set, tm->tm_min); 95 out_8(®s->hour_set, tm->tm_hour); 96 97 /* set time sequence */ 98 out_8(®s->set_time, 0x1); 99 out_8(®s->set_time, 0x3); 100 out_8(®s->set_time, 0x1); 101 out_8(®s->set_time, 0x0); 102 } 103 104 static int mpc5121_rtc_read_time(struct device *dev, struct rtc_time *tm) 105 { 106 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 107 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 108 unsigned long now; 109 110 /* 111 * linux time is actual_time plus the offset saved in target_time 112 */ 113 now = in_be32(®s->actual_time) + in_be32(®s->target_time); 114 115 rtc_time_to_tm(now, tm); 116 117 /* 118 * update second minute hour registers 119 * so alarms will work 120 */ 121 mpc5121_rtc_update_smh(regs, tm); 122 123 return rtc_valid_tm(tm); 124 } 125 126 static int mpc5121_rtc_set_time(struct device *dev, struct rtc_time *tm) 127 { 128 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 129 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 130 int ret; 131 unsigned long now; 132 133 /* 134 * The actual_time register is read only so we write the offset 135 * between it and linux time to the target_time register. 136 */ 137 ret = rtc_tm_to_time(tm, &now); 138 if (ret == 0) 139 out_be32(®s->target_time, now - in_be32(®s->actual_time)); 140 141 /* 142 * update second minute hour registers 143 * so alarms will work 144 */ 145 mpc5121_rtc_update_smh(regs, tm); 146 147 return 0; 148 } 149 150 static int mpc5200_rtc_read_time(struct device *dev, struct rtc_time *tm) 151 { 152 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 153 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 154 int tmp; 155 156 tm->tm_sec = in_8(®s->second); 157 tm->tm_min = in_8(®s->minute); 158 159 /* 12 hour format? */ 160 if (in_8(®s->hour) & 0x20) 161 tm->tm_hour = (in_8(®s->hour) >> 1) + 162 (in_8(®s->hour) & 1 ? 12 : 0); 163 else 164 tm->tm_hour = in_8(®s->hour); 165 166 tmp = in_8(®s->wday_mday); 167 tm->tm_mday = tmp & 0x1f; 168 tm->tm_mon = in_8(®s->month) - 1; 169 tm->tm_year = in_be16(®s->year) - 1900; 170 tm->tm_wday = (tmp >> 5) % 7; 171 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); 172 tm->tm_isdst = 0; 173 174 return 0; 175 } 176 177 static int mpc5200_rtc_set_time(struct device *dev, struct rtc_time *tm) 178 { 179 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 180 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 181 182 mpc5121_rtc_update_smh(regs, tm); 183 184 /* date */ 185 out_8(®s->month_set, tm->tm_mon + 1); 186 out_8(®s->weekday_set, tm->tm_wday ? tm->tm_wday : 7); 187 out_8(®s->date_set, tm->tm_mday); 188 out_be16(®s->year_set, tm->tm_year + 1900); 189 190 /* set date sequence */ 191 out_8(®s->set_date, 0x1); 192 out_8(®s->set_date, 0x3); 193 out_8(®s->set_date, 0x1); 194 out_8(®s->set_date, 0x0); 195 196 return 0; 197 } 198 199 static int mpc5121_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) 200 { 201 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 202 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 203 204 *alarm = rtc->wkalarm; 205 206 alarm->pending = in_8(®s->alm_status); 207 208 return 0; 209 } 210 211 static int mpc5121_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) 212 { 213 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 214 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 215 216 /* 217 * the alarm has no seconds so deal with it 218 */ 219 if (alarm->time.tm_sec) { 220 alarm->time.tm_sec = 0; 221 alarm->time.tm_min++; 222 if (alarm->time.tm_min >= 60) { 223 alarm->time.tm_min = 0; 224 alarm->time.tm_hour++; 225 if (alarm->time.tm_hour >= 24) 226 alarm->time.tm_hour = 0; 227 } 228 } 229 230 alarm->time.tm_mday = -1; 231 alarm->time.tm_mon = -1; 232 alarm->time.tm_year = -1; 233 234 out_8(®s->alm_min_set, alarm->time.tm_min); 235 out_8(®s->alm_hour_set, alarm->time.tm_hour); 236 237 out_8(®s->alm_enable, alarm->enabled); 238 239 rtc->wkalarm = *alarm; 240 return 0; 241 } 242 243 static irqreturn_t mpc5121_rtc_handler(int irq, void *dev) 244 { 245 struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev); 246 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 247 248 if (in_8(®s->int_alm)) { 249 /* acknowledge and clear status */ 250 out_8(®s->int_alm, 1); 251 out_8(®s->alm_status, 1); 252 253 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF); 254 return IRQ_HANDLED; 255 } 256 257 return IRQ_NONE; 258 } 259 260 static irqreturn_t mpc5121_rtc_handler_upd(int irq, void *dev) 261 { 262 struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev); 263 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 264 265 if (in_8(®s->int_sec) && (in_8(®s->int_enable) & 0x1)) { 266 /* acknowledge */ 267 out_8(®s->int_sec, 1); 268 269 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_UF); 270 return IRQ_HANDLED; 271 } 272 273 return IRQ_NONE; 274 } 275 276 static int mpc5121_rtc_alarm_irq_enable(struct device *dev, 277 unsigned int enabled) 278 { 279 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); 280 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 281 int val; 282 283 if (enabled) 284 val = 1; 285 else 286 val = 0; 287 288 out_8(®s->alm_enable, val); 289 rtc->wkalarm.enabled = val; 290 291 return 0; 292 } 293 294 static const struct rtc_class_ops mpc5121_rtc_ops = { 295 .read_time = mpc5121_rtc_read_time, 296 .set_time = mpc5121_rtc_set_time, 297 .read_alarm = mpc5121_rtc_read_alarm, 298 .set_alarm = mpc5121_rtc_set_alarm, 299 .alarm_irq_enable = mpc5121_rtc_alarm_irq_enable, 300 }; 301 302 static const struct rtc_class_ops mpc5200_rtc_ops = { 303 .read_time = mpc5200_rtc_read_time, 304 .set_time = mpc5200_rtc_set_time, 305 .read_alarm = mpc5121_rtc_read_alarm, 306 .set_alarm = mpc5121_rtc_set_alarm, 307 .alarm_irq_enable = mpc5121_rtc_alarm_irq_enable, 308 }; 309 310 static int mpc5121_rtc_probe(struct platform_device *op) 311 { 312 struct mpc5121_rtc_data *rtc; 313 int err = 0; 314 315 rtc = kzalloc(sizeof(*rtc), GFP_KERNEL); 316 if (!rtc) 317 return -ENOMEM; 318 319 rtc->regs = of_iomap(op->dev.of_node, 0); 320 if (!rtc->regs) { 321 dev_err(&op->dev, "%s: couldn't map io space\n", __func__); 322 err = -ENOSYS; 323 goto out_free; 324 } 325 326 device_init_wakeup(&op->dev, 1); 327 328 dev_set_drvdata(&op->dev, rtc); 329 330 rtc->irq = irq_of_parse_and_map(op->dev.of_node, 1); 331 err = request_irq(rtc->irq, mpc5121_rtc_handler, 0, 332 "mpc5121-rtc", &op->dev); 333 if (err) { 334 dev_err(&op->dev, "%s: could not request irq: %i\n", 335 __func__, rtc->irq); 336 goto out_dispose; 337 } 338 339 rtc->irq_periodic = irq_of_parse_and_map(op->dev.of_node, 0); 340 err = request_irq(rtc->irq_periodic, mpc5121_rtc_handler_upd, 341 0, "mpc5121-rtc_upd", &op->dev); 342 if (err) { 343 dev_err(&op->dev, "%s: could not request irq: %i\n", 344 __func__, rtc->irq_periodic); 345 goto out_dispose2; 346 } 347 348 if (of_device_is_compatible(op->dev.of_node, "fsl,mpc5121-rtc")) { 349 u32 ka; 350 ka = in_be32(&rtc->regs->keep_alive); 351 if (ka & 0x02) { 352 dev_warn(&op->dev, 353 "mpc5121-rtc: Battery or oscillator failure!\n"); 354 out_be32(&rtc->regs->keep_alive, ka); 355 } 356 357 rtc->rtc = rtc_device_register("mpc5121-rtc", &op->dev, 358 &mpc5121_rtc_ops, THIS_MODULE); 359 } else { 360 rtc->rtc = rtc_device_register("mpc5200-rtc", &op->dev, 361 &mpc5200_rtc_ops, THIS_MODULE); 362 } 363 364 if (IS_ERR(rtc->rtc)) { 365 err = PTR_ERR(rtc->rtc); 366 goto out_free_irq; 367 } 368 rtc->rtc->uie_unsupported = 1; 369 370 return 0; 371 372 out_free_irq: 373 free_irq(rtc->irq_periodic, &op->dev); 374 out_dispose2: 375 irq_dispose_mapping(rtc->irq_periodic); 376 free_irq(rtc->irq, &op->dev); 377 out_dispose: 378 irq_dispose_mapping(rtc->irq); 379 iounmap(rtc->regs); 380 out_free: 381 kfree(rtc); 382 383 return err; 384 } 385 386 static int mpc5121_rtc_remove(struct platform_device *op) 387 { 388 struct mpc5121_rtc_data *rtc = dev_get_drvdata(&op->dev); 389 struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 390 391 /* disable interrupt, so there are no nasty surprises */ 392 out_8(®s->alm_enable, 0); 393 out_8(®s->int_enable, in_8(®s->int_enable) & ~0x1); 394 395 rtc_device_unregister(rtc->rtc); 396 iounmap(rtc->regs); 397 free_irq(rtc->irq, &op->dev); 398 free_irq(rtc->irq_periodic, &op->dev); 399 irq_dispose_mapping(rtc->irq); 400 irq_dispose_mapping(rtc->irq_periodic); 401 dev_set_drvdata(&op->dev, NULL); 402 kfree(rtc); 403 404 return 0; 405 } 406 407 #ifdef CONFIG_OF 408 static struct of_device_id mpc5121_rtc_match[] = { 409 { .compatible = "fsl,mpc5121-rtc", }, 410 { .compatible = "fsl,mpc5200-rtc", }, 411 {}, 412 }; 413 #endif 414 415 static struct platform_driver mpc5121_rtc_driver = { 416 .driver = { 417 .name = "mpc5121-rtc", 418 .owner = THIS_MODULE, 419 .of_match_table = of_match_ptr(mpc5121_rtc_match), 420 }, 421 .probe = mpc5121_rtc_probe, 422 .remove = mpc5121_rtc_remove, 423 }; 424 425 module_platform_driver(mpc5121_rtc_driver); 426 427 MODULE_LICENSE("GPL"); 428 MODULE_AUTHOR("John Rigby <jcrigby@gmail.com>"); 429