1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * RTC Driver for X-Powers AC100 4 * 5 * Copyright (c) 2016 Chen-Yu Tsai 6 * 7 * Chen-Yu Tsai <wens@csie.org> 8 */ 9 10 #include <linux/bcd.h> 11 #include <linux/clk-provider.h> 12 #include <linux/device.h> 13 #include <linux/interrupt.h> 14 #include <linux/kernel.h> 15 #include <linux/mfd/ac100.h> 16 #include <linux/module.h> 17 #include <linux/mutex.h> 18 #include <linux/of.h> 19 #include <linux/platform_device.h> 20 #include <linux/regmap.h> 21 #include <linux/rtc.h> 22 #include <linux/types.h> 23 24 /* Control register */ 25 #define AC100_RTC_CTRL_24HOUR BIT(0) 26 27 /* Clock output register bits */ 28 #define AC100_CLKOUT_PRE_DIV_SHIFT 5 29 #define AC100_CLKOUT_PRE_DIV_WIDTH 3 30 #define AC100_CLKOUT_MUX_SHIFT 4 31 #define AC100_CLKOUT_MUX_WIDTH 1 32 #define AC100_CLKOUT_DIV_SHIFT 1 33 #define AC100_CLKOUT_DIV_WIDTH 3 34 #define AC100_CLKOUT_EN BIT(0) 35 36 /* RTC */ 37 #define AC100_RTC_SEC_MASK GENMASK(6, 0) 38 #define AC100_RTC_MIN_MASK GENMASK(6, 0) 39 #define AC100_RTC_HOU_MASK GENMASK(5, 0) 40 #define AC100_RTC_WEE_MASK GENMASK(2, 0) 41 #define AC100_RTC_DAY_MASK GENMASK(5, 0) 42 #define AC100_RTC_MON_MASK GENMASK(4, 0) 43 #define AC100_RTC_YEA_MASK GENMASK(7, 0) 44 #define AC100_RTC_YEA_LEAP BIT(15) 45 #define AC100_RTC_UPD_TRIGGER BIT(15) 46 47 /* Alarm (wall clock) */ 48 #define AC100_ALM_INT_ENABLE BIT(0) 49 50 #define AC100_ALM_SEC_MASK GENMASK(6, 0) 51 #define AC100_ALM_MIN_MASK GENMASK(6, 0) 52 #define AC100_ALM_HOU_MASK GENMASK(5, 0) 53 #define AC100_ALM_WEE_MASK GENMASK(2, 0) 54 #define AC100_ALM_DAY_MASK GENMASK(5, 0) 55 #define AC100_ALM_MON_MASK GENMASK(4, 0) 56 #define AC100_ALM_YEA_MASK GENMASK(7, 0) 57 #define AC100_ALM_ENABLE_FLAG BIT(15) 58 #define AC100_ALM_UPD_TRIGGER BIT(15) 59 60 /* 61 * The year parameter passed to the driver is usually an offset relative to 62 * the year 1900. This macro is used to convert this offset to another one 63 * relative to the minimum year allowed by the hardware. 64 * 65 * The year range is 1970 - 2069. This range is selected to match Allwinner's 66 * driver. 67 */ 68 #define AC100_YEAR_MIN 1970 69 #define AC100_YEAR_MAX 2069 70 #define AC100_YEAR_OFF (AC100_YEAR_MIN - 1900) 71 72 struct ac100_clkout { 73 struct clk_hw hw; 74 struct regmap *regmap; 75 u8 offset; 76 }; 77 78 #define to_ac100_clkout(_hw) container_of(_hw, struct ac100_clkout, hw) 79 80 #define AC100_RTC_32K_NAME "ac100-rtc-32k" 81 #define AC100_RTC_32K_RATE 32768 82 #define AC100_CLKOUT_NUM 3 83 84 static const char * const ac100_clkout_names[AC100_CLKOUT_NUM] = { 85 "ac100-cko1-rtc", 86 "ac100-cko2-rtc", 87 "ac100-cko3-rtc", 88 }; 89 90 struct ac100_rtc_dev { 91 struct rtc_device *rtc; 92 struct device *dev; 93 struct regmap *regmap; 94 int irq; 95 unsigned long alarm; 96 97 struct clk_hw *rtc_32k_clk; 98 struct ac100_clkout clks[AC100_CLKOUT_NUM]; 99 struct clk_hw_onecell_data *clk_data; 100 }; 101 102 /** 103 * Clock controls for 3 clock output pins 104 */ 105 106 static const struct clk_div_table ac100_clkout_prediv[] = { 107 { .val = 0, .div = 1 }, 108 { .val = 1, .div = 2 }, 109 { .val = 2, .div = 4 }, 110 { .val = 3, .div = 8 }, 111 { .val = 4, .div = 16 }, 112 { .val = 5, .div = 32 }, 113 { .val = 6, .div = 64 }, 114 { .val = 7, .div = 122 }, 115 { }, 116 }; 117 118 /* Abuse the fact that one parent is 32768 Hz, and the other is 4 MHz */ 119 static unsigned long ac100_clkout_recalc_rate(struct clk_hw *hw, 120 unsigned long prate) 121 { 122 struct ac100_clkout *clk = to_ac100_clkout(hw); 123 unsigned int reg, div; 124 125 regmap_read(clk->regmap, clk->offset, ®); 126 127 /* Handle pre-divider first */ 128 if (prate != AC100_RTC_32K_RATE) { 129 div = (reg >> AC100_CLKOUT_PRE_DIV_SHIFT) & 130 ((1 << AC100_CLKOUT_PRE_DIV_WIDTH) - 1); 131 prate = divider_recalc_rate(hw, prate, div, 132 ac100_clkout_prediv, 0, 133 AC100_CLKOUT_PRE_DIV_WIDTH); 134 } 135 136 div = (reg >> AC100_CLKOUT_DIV_SHIFT) & 137 (BIT(AC100_CLKOUT_DIV_WIDTH) - 1); 138 return divider_recalc_rate(hw, prate, div, NULL, 139 CLK_DIVIDER_POWER_OF_TWO, 140 AC100_CLKOUT_DIV_WIDTH); 141 } 142 143 static long ac100_clkout_round_rate(struct clk_hw *hw, unsigned long rate, 144 unsigned long prate) 145 { 146 unsigned long best_rate = 0, tmp_rate, tmp_prate; 147 int i; 148 149 if (prate == AC100_RTC_32K_RATE) 150 return divider_round_rate(hw, rate, &prate, NULL, 151 AC100_CLKOUT_DIV_WIDTH, 152 CLK_DIVIDER_POWER_OF_TWO); 153 154 for (i = 0; ac100_clkout_prediv[i].div; i++) { 155 tmp_prate = DIV_ROUND_UP(prate, ac100_clkout_prediv[i].val); 156 tmp_rate = divider_round_rate(hw, rate, &tmp_prate, NULL, 157 AC100_CLKOUT_DIV_WIDTH, 158 CLK_DIVIDER_POWER_OF_TWO); 159 160 if (tmp_rate > rate) 161 continue; 162 if (rate - tmp_rate < best_rate - tmp_rate) 163 best_rate = tmp_rate; 164 } 165 166 return best_rate; 167 } 168 169 static int ac100_clkout_determine_rate(struct clk_hw *hw, 170 struct clk_rate_request *req) 171 { 172 struct clk_hw *best_parent; 173 unsigned long best = 0; 174 int i, num_parents = clk_hw_get_num_parents(hw); 175 176 for (i = 0; i < num_parents; i++) { 177 struct clk_hw *parent = clk_hw_get_parent_by_index(hw, i); 178 unsigned long tmp, prate; 179 180 /* 181 * The clock has two parents, one is a fixed clock which is 182 * internally registered by the ac100 driver. The other parent 183 * is a clock from the codec side of the chip, which we 184 * properly declare and reference in the devicetree and is 185 * not implemented in any driver right now. 186 * If the clock core looks for the parent of that second 187 * missing clock, it can't find one that is registered and 188 * returns NULL. 189 * So we end up in a situation where clk_hw_get_num_parents 190 * returns the amount of clocks we can be parented to, but 191 * clk_hw_get_parent_by_index will not return the orphan 192 * clocks. 193 * Thus we need to check if the parent exists before 194 * we get the parent rate, so we could use the RTC 195 * without waiting for the codec to be supported. 196 */ 197 if (!parent) 198 continue; 199 200 prate = clk_hw_get_rate(parent); 201 202 tmp = ac100_clkout_round_rate(hw, req->rate, prate); 203 204 if (tmp > req->rate) 205 continue; 206 if (req->rate - tmp < req->rate - best) { 207 best = tmp; 208 best_parent = parent; 209 } 210 } 211 212 if (!best) 213 return -EINVAL; 214 215 req->best_parent_hw = best_parent; 216 req->best_parent_rate = best; 217 req->rate = best; 218 219 return 0; 220 } 221 222 static int ac100_clkout_set_rate(struct clk_hw *hw, unsigned long rate, 223 unsigned long prate) 224 { 225 struct ac100_clkout *clk = to_ac100_clkout(hw); 226 int div = 0, pre_div = 0; 227 228 do { 229 div = divider_get_val(rate * ac100_clkout_prediv[pre_div].div, 230 prate, NULL, AC100_CLKOUT_DIV_WIDTH, 231 CLK_DIVIDER_POWER_OF_TWO); 232 if (div >= 0) 233 break; 234 } while (prate != AC100_RTC_32K_RATE && 235 ac100_clkout_prediv[++pre_div].div); 236 237 if (div < 0) 238 return div; 239 240 pre_div = ac100_clkout_prediv[pre_div].val; 241 242 regmap_update_bits(clk->regmap, clk->offset, 243 ((1 << AC100_CLKOUT_DIV_WIDTH) - 1) << AC100_CLKOUT_DIV_SHIFT | 244 ((1 << AC100_CLKOUT_PRE_DIV_WIDTH) - 1) << AC100_CLKOUT_PRE_DIV_SHIFT, 245 (div - 1) << AC100_CLKOUT_DIV_SHIFT | 246 (pre_div - 1) << AC100_CLKOUT_PRE_DIV_SHIFT); 247 248 return 0; 249 } 250 251 static int ac100_clkout_prepare(struct clk_hw *hw) 252 { 253 struct ac100_clkout *clk = to_ac100_clkout(hw); 254 255 return regmap_update_bits(clk->regmap, clk->offset, AC100_CLKOUT_EN, 256 AC100_CLKOUT_EN); 257 } 258 259 static void ac100_clkout_unprepare(struct clk_hw *hw) 260 { 261 struct ac100_clkout *clk = to_ac100_clkout(hw); 262 263 regmap_update_bits(clk->regmap, clk->offset, AC100_CLKOUT_EN, 0); 264 } 265 266 static int ac100_clkout_is_prepared(struct clk_hw *hw) 267 { 268 struct ac100_clkout *clk = to_ac100_clkout(hw); 269 unsigned int reg; 270 271 regmap_read(clk->regmap, clk->offset, ®); 272 273 return reg & AC100_CLKOUT_EN; 274 } 275 276 static u8 ac100_clkout_get_parent(struct clk_hw *hw) 277 { 278 struct ac100_clkout *clk = to_ac100_clkout(hw); 279 unsigned int reg; 280 281 regmap_read(clk->regmap, clk->offset, ®); 282 283 return (reg >> AC100_CLKOUT_MUX_SHIFT) & 0x1; 284 } 285 286 static int ac100_clkout_set_parent(struct clk_hw *hw, u8 index) 287 { 288 struct ac100_clkout *clk = to_ac100_clkout(hw); 289 290 return regmap_update_bits(clk->regmap, clk->offset, 291 BIT(AC100_CLKOUT_MUX_SHIFT), 292 index ? BIT(AC100_CLKOUT_MUX_SHIFT) : 0); 293 } 294 295 static const struct clk_ops ac100_clkout_ops = { 296 .prepare = ac100_clkout_prepare, 297 .unprepare = ac100_clkout_unprepare, 298 .is_prepared = ac100_clkout_is_prepared, 299 .recalc_rate = ac100_clkout_recalc_rate, 300 .determine_rate = ac100_clkout_determine_rate, 301 .get_parent = ac100_clkout_get_parent, 302 .set_parent = ac100_clkout_set_parent, 303 .set_rate = ac100_clkout_set_rate, 304 }; 305 306 static int ac100_rtc_register_clks(struct ac100_rtc_dev *chip) 307 { 308 struct device_node *np = chip->dev->of_node; 309 const char *parents[2] = {AC100_RTC_32K_NAME}; 310 int i, ret; 311 312 chip->clk_data = devm_kzalloc(chip->dev, 313 struct_size(chip->clk_data, hws, 314 AC100_CLKOUT_NUM), 315 GFP_KERNEL); 316 if (!chip->clk_data) 317 return -ENOMEM; 318 319 chip->rtc_32k_clk = clk_hw_register_fixed_rate(chip->dev, 320 AC100_RTC_32K_NAME, 321 NULL, 0, 322 AC100_RTC_32K_RATE); 323 if (IS_ERR(chip->rtc_32k_clk)) { 324 ret = PTR_ERR(chip->rtc_32k_clk); 325 dev_err(chip->dev, "Failed to register RTC-32k clock: %d\n", 326 ret); 327 return ret; 328 } 329 330 parents[1] = of_clk_get_parent_name(np, 0); 331 if (!parents[1]) { 332 dev_err(chip->dev, "Failed to get ADDA 4M clock\n"); 333 return -EINVAL; 334 } 335 336 for (i = 0; i < AC100_CLKOUT_NUM; i++) { 337 struct ac100_clkout *clk = &chip->clks[i]; 338 struct clk_init_data init = { 339 .name = ac100_clkout_names[i], 340 .ops = &ac100_clkout_ops, 341 .parent_names = parents, 342 .num_parents = ARRAY_SIZE(parents), 343 .flags = 0, 344 }; 345 346 of_property_read_string_index(np, "clock-output-names", 347 i, &init.name); 348 clk->regmap = chip->regmap; 349 clk->offset = AC100_CLKOUT_CTRL1 + i; 350 clk->hw.init = &init; 351 352 ret = devm_clk_hw_register(chip->dev, &clk->hw); 353 if (ret) { 354 dev_err(chip->dev, "Failed to register clk '%s': %d\n", 355 init.name, ret); 356 goto err_unregister_rtc_32k; 357 } 358 359 chip->clk_data->hws[i] = &clk->hw; 360 } 361 362 chip->clk_data->num = i; 363 ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, chip->clk_data); 364 if (ret) 365 goto err_unregister_rtc_32k; 366 367 return 0; 368 369 err_unregister_rtc_32k: 370 clk_unregister_fixed_rate(chip->rtc_32k_clk->clk); 371 372 return ret; 373 } 374 375 static void ac100_rtc_unregister_clks(struct ac100_rtc_dev *chip) 376 { 377 of_clk_del_provider(chip->dev->of_node); 378 clk_unregister_fixed_rate(chip->rtc_32k_clk->clk); 379 } 380 381 /** 382 * RTC related bits 383 */ 384 static int ac100_rtc_get_time(struct device *dev, struct rtc_time *rtc_tm) 385 { 386 struct ac100_rtc_dev *chip = dev_get_drvdata(dev); 387 struct regmap *regmap = chip->regmap; 388 u16 reg[7]; 389 int ret; 390 391 ret = regmap_bulk_read(regmap, AC100_RTC_SEC, reg, 7); 392 if (ret) 393 return ret; 394 395 rtc_tm->tm_sec = bcd2bin(reg[0] & AC100_RTC_SEC_MASK); 396 rtc_tm->tm_min = bcd2bin(reg[1] & AC100_RTC_MIN_MASK); 397 rtc_tm->tm_hour = bcd2bin(reg[2] & AC100_RTC_HOU_MASK); 398 rtc_tm->tm_wday = bcd2bin(reg[3] & AC100_RTC_WEE_MASK); 399 rtc_tm->tm_mday = bcd2bin(reg[4] & AC100_RTC_DAY_MASK); 400 rtc_tm->tm_mon = bcd2bin(reg[5] & AC100_RTC_MON_MASK) - 1; 401 rtc_tm->tm_year = bcd2bin(reg[6] & AC100_RTC_YEA_MASK) + 402 AC100_YEAR_OFF; 403 404 return 0; 405 } 406 407 static int ac100_rtc_set_time(struct device *dev, struct rtc_time *rtc_tm) 408 { 409 struct ac100_rtc_dev *chip = dev_get_drvdata(dev); 410 struct regmap *regmap = chip->regmap; 411 int year; 412 u16 reg[8]; 413 414 /* our RTC has a limited year range... */ 415 year = rtc_tm->tm_year - AC100_YEAR_OFF; 416 if (year < 0 || year > (AC100_YEAR_MAX - 1900)) { 417 dev_err(dev, "rtc only supports year in range %d - %d\n", 418 AC100_YEAR_MIN, AC100_YEAR_MAX); 419 return -EINVAL; 420 } 421 422 /* convert to BCD */ 423 reg[0] = bin2bcd(rtc_tm->tm_sec) & AC100_RTC_SEC_MASK; 424 reg[1] = bin2bcd(rtc_tm->tm_min) & AC100_RTC_MIN_MASK; 425 reg[2] = bin2bcd(rtc_tm->tm_hour) & AC100_RTC_HOU_MASK; 426 reg[3] = bin2bcd(rtc_tm->tm_wday) & AC100_RTC_WEE_MASK; 427 reg[4] = bin2bcd(rtc_tm->tm_mday) & AC100_RTC_DAY_MASK; 428 reg[5] = bin2bcd(rtc_tm->tm_mon + 1) & AC100_RTC_MON_MASK; 429 reg[6] = bin2bcd(year) & AC100_RTC_YEA_MASK; 430 /* trigger write */ 431 reg[7] = AC100_RTC_UPD_TRIGGER; 432 433 /* Is it a leap year? */ 434 if (is_leap_year(year + AC100_YEAR_OFF + 1900)) 435 reg[6] |= AC100_RTC_YEA_LEAP; 436 437 return regmap_bulk_write(regmap, AC100_RTC_SEC, reg, 8); 438 } 439 440 static int ac100_rtc_alarm_irq_enable(struct device *dev, unsigned int en) 441 { 442 struct ac100_rtc_dev *chip = dev_get_drvdata(dev); 443 struct regmap *regmap = chip->regmap; 444 unsigned int val; 445 446 val = en ? AC100_ALM_INT_ENABLE : 0; 447 448 return regmap_write(regmap, AC100_ALM_INT_ENA, val); 449 } 450 451 static int ac100_rtc_get_alarm(struct device *dev, struct rtc_wkalrm *alrm) 452 { 453 struct ac100_rtc_dev *chip = dev_get_drvdata(dev); 454 struct regmap *regmap = chip->regmap; 455 struct rtc_time *alrm_tm = &alrm->time; 456 u16 reg[7]; 457 unsigned int val; 458 int ret; 459 460 ret = regmap_read(regmap, AC100_ALM_INT_ENA, &val); 461 if (ret) 462 return ret; 463 464 alrm->enabled = !!(val & AC100_ALM_INT_ENABLE); 465 466 ret = regmap_bulk_read(regmap, AC100_ALM_SEC, reg, 7); 467 if (ret) 468 return ret; 469 470 alrm_tm->tm_sec = bcd2bin(reg[0] & AC100_ALM_SEC_MASK); 471 alrm_tm->tm_min = bcd2bin(reg[1] & AC100_ALM_MIN_MASK); 472 alrm_tm->tm_hour = bcd2bin(reg[2] & AC100_ALM_HOU_MASK); 473 alrm_tm->tm_wday = bcd2bin(reg[3] & AC100_ALM_WEE_MASK); 474 alrm_tm->tm_mday = bcd2bin(reg[4] & AC100_ALM_DAY_MASK); 475 alrm_tm->tm_mon = bcd2bin(reg[5] & AC100_ALM_MON_MASK) - 1; 476 alrm_tm->tm_year = bcd2bin(reg[6] & AC100_ALM_YEA_MASK) + 477 AC100_YEAR_OFF; 478 479 return 0; 480 } 481 482 static int ac100_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) 483 { 484 struct ac100_rtc_dev *chip = dev_get_drvdata(dev); 485 struct regmap *regmap = chip->regmap; 486 struct rtc_time *alrm_tm = &alrm->time; 487 u16 reg[8]; 488 int year; 489 int ret; 490 491 /* our alarm has a limited year range... */ 492 year = alrm_tm->tm_year - AC100_YEAR_OFF; 493 if (year < 0 || year > (AC100_YEAR_MAX - 1900)) { 494 dev_err(dev, "alarm only supports year in range %d - %d\n", 495 AC100_YEAR_MIN, AC100_YEAR_MAX); 496 return -EINVAL; 497 } 498 499 /* convert to BCD */ 500 reg[0] = (bin2bcd(alrm_tm->tm_sec) & AC100_ALM_SEC_MASK) | 501 AC100_ALM_ENABLE_FLAG; 502 reg[1] = (bin2bcd(alrm_tm->tm_min) & AC100_ALM_MIN_MASK) | 503 AC100_ALM_ENABLE_FLAG; 504 reg[2] = (bin2bcd(alrm_tm->tm_hour) & AC100_ALM_HOU_MASK) | 505 AC100_ALM_ENABLE_FLAG; 506 /* Do not enable weekday alarm */ 507 reg[3] = bin2bcd(alrm_tm->tm_wday) & AC100_ALM_WEE_MASK; 508 reg[4] = (bin2bcd(alrm_tm->tm_mday) & AC100_ALM_DAY_MASK) | 509 AC100_ALM_ENABLE_FLAG; 510 reg[5] = (bin2bcd(alrm_tm->tm_mon + 1) & AC100_ALM_MON_MASK) | 511 AC100_ALM_ENABLE_FLAG; 512 reg[6] = (bin2bcd(year) & AC100_ALM_YEA_MASK) | 513 AC100_ALM_ENABLE_FLAG; 514 /* trigger write */ 515 reg[7] = AC100_ALM_UPD_TRIGGER; 516 517 ret = regmap_bulk_write(regmap, AC100_ALM_SEC, reg, 8); 518 if (ret) 519 return ret; 520 521 return ac100_rtc_alarm_irq_enable(dev, alrm->enabled); 522 } 523 524 static irqreturn_t ac100_rtc_irq(int irq, void *data) 525 { 526 struct ac100_rtc_dev *chip = data; 527 struct regmap *regmap = chip->regmap; 528 unsigned int val = 0; 529 int ret; 530 531 mutex_lock(&chip->rtc->ops_lock); 532 533 /* read status */ 534 ret = regmap_read(regmap, AC100_ALM_INT_STA, &val); 535 if (ret) 536 goto out; 537 538 if (val & AC100_ALM_INT_ENABLE) { 539 /* signal rtc framework */ 540 rtc_update_irq(chip->rtc, 1, RTC_AF | RTC_IRQF); 541 542 /* clear status */ 543 ret = regmap_write(regmap, AC100_ALM_INT_STA, val); 544 if (ret) 545 goto out; 546 547 /* disable interrupt */ 548 ret = ac100_rtc_alarm_irq_enable(chip->dev, 0); 549 if (ret) 550 goto out; 551 } 552 553 out: 554 mutex_unlock(&chip->rtc->ops_lock); 555 return IRQ_HANDLED; 556 } 557 558 static const struct rtc_class_ops ac100_rtc_ops = { 559 .read_time = ac100_rtc_get_time, 560 .set_time = ac100_rtc_set_time, 561 .read_alarm = ac100_rtc_get_alarm, 562 .set_alarm = ac100_rtc_set_alarm, 563 .alarm_irq_enable = ac100_rtc_alarm_irq_enable, 564 }; 565 566 static int ac100_rtc_probe(struct platform_device *pdev) 567 { 568 struct ac100_dev *ac100 = dev_get_drvdata(pdev->dev.parent); 569 struct ac100_rtc_dev *chip; 570 int ret; 571 572 chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL); 573 if (!chip) 574 return -ENOMEM; 575 576 platform_set_drvdata(pdev, chip); 577 chip->dev = &pdev->dev; 578 chip->regmap = ac100->regmap; 579 580 chip->irq = platform_get_irq(pdev, 0); 581 if (chip->irq < 0) { 582 dev_err(&pdev->dev, "No IRQ resource\n"); 583 return chip->irq; 584 } 585 586 chip->rtc = devm_rtc_allocate_device(&pdev->dev); 587 if (IS_ERR(chip->rtc)) 588 return PTR_ERR(chip->rtc); 589 590 chip->rtc->ops = &ac100_rtc_ops; 591 592 ret = devm_request_threaded_irq(&pdev->dev, chip->irq, NULL, 593 ac100_rtc_irq, 594 IRQF_SHARED | IRQF_ONESHOT, 595 dev_name(&pdev->dev), chip); 596 if (ret) { 597 dev_err(&pdev->dev, "Could not request IRQ\n"); 598 return ret; 599 } 600 601 /* always use 24 hour mode */ 602 regmap_write_bits(chip->regmap, AC100_RTC_CTRL, AC100_RTC_CTRL_24HOUR, 603 AC100_RTC_CTRL_24HOUR); 604 605 /* disable counter alarm interrupt */ 606 regmap_write(chip->regmap, AC100_ALM_INT_ENA, 0); 607 608 /* clear counter alarm pending interrupts */ 609 regmap_write(chip->regmap, AC100_ALM_INT_STA, AC100_ALM_INT_ENABLE); 610 611 ret = ac100_rtc_register_clks(chip); 612 if (ret) 613 return ret; 614 615 ret = rtc_register_device(chip->rtc); 616 if (ret) { 617 dev_err(&pdev->dev, "unable to register device\n"); 618 return ret; 619 } 620 621 dev_info(&pdev->dev, "RTC enabled\n"); 622 623 return 0; 624 } 625 626 static int ac100_rtc_remove(struct platform_device *pdev) 627 { 628 struct ac100_rtc_dev *chip = platform_get_drvdata(pdev); 629 630 ac100_rtc_unregister_clks(chip); 631 632 return 0; 633 } 634 635 static const struct of_device_id ac100_rtc_match[] = { 636 { .compatible = "x-powers,ac100-rtc" }, 637 { }, 638 }; 639 MODULE_DEVICE_TABLE(of, ac100_rtc_match); 640 641 static struct platform_driver ac100_rtc_driver = { 642 .probe = ac100_rtc_probe, 643 .remove = ac100_rtc_remove, 644 .driver = { 645 .name = "ac100-rtc", 646 .of_match_table = of_match_ptr(ac100_rtc_match), 647 }, 648 }; 649 module_platform_driver(ac100_rtc_driver); 650 651 MODULE_DESCRIPTION("X-Powers AC100 RTC driver"); 652 MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>"); 653 MODULE_LICENSE("GPL v2"); 654