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