1 /* 2 * ACPI support for Intel Lynxpoint LPSS. 3 * 4 * Copyright (C) 2013, Intel Corporation 5 * Authors: Mika Westerberg <mika.westerberg@linux.intel.com> 6 * Rafael J. Wysocki <rafael.j.wysocki@intel.com> 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/acpi.h> 14 #include <linux/clk.h> 15 #include <linux/clkdev.h> 16 #include <linux/clk-provider.h> 17 #include <linux/err.h> 18 #include <linux/io.h> 19 #include <linux/platform_device.h> 20 #include <linux/platform_data/clk-lpss.h> 21 #include <linux/pm_runtime.h> 22 #include <linux/delay.h> 23 24 #include "internal.h" 25 26 ACPI_MODULE_NAME("acpi_lpss"); 27 28 #ifdef CONFIG_X86_INTEL_LPSS 29 30 #define LPSS_ADDR(desc) ((unsigned long)&desc) 31 32 #define LPSS_CLK_SIZE 0x04 33 #define LPSS_LTR_SIZE 0x18 34 35 /* Offsets relative to LPSS_PRIVATE_OFFSET */ 36 #define LPSS_CLK_DIVIDER_DEF_MASK (BIT(1) | BIT(16)) 37 #define LPSS_RESETS 0x04 38 #define LPSS_RESETS_RESET_FUNC BIT(0) 39 #define LPSS_RESETS_RESET_APB BIT(1) 40 #define LPSS_GENERAL 0x08 41 #define LPSS_GENERAL_LTR_MODE_SW BIT(2) 42 #define LPSS_GENERAL_UART_RTS_OVRD BIT(3) 43 #define LPSS_SW_LTR 0x10 44 #define LPSS_AUTO_LTR 0x14 45 #define LPSS_LTR_SNOOP_REQ BIT(15) 46 #define LPSS_LTR_SNOOP_MASK 0x0000FFFF 47 #define LPSS_LTR_SNOOP_LAT_1US 0x800 48 #define LPSS_LTR_SNOOP_LAT_32US 0xC00 49 #define LPSS_LTR_SNOOP_LAT_SHIFT 5 50 #define LPSS_LTR_SNOOP_LAT_CUTOFF 3000 51 #define LPSS_LTR_MAX_VAL 0x3FF 52 #define LPSS_TX_INT 0x20 53 #define LPSS_TX_INT_MASK BIT(1) 54 55 #define LPSS_PRV_REG_COUNT 9 56 57 struct lpss_shared_clock { 58 const char *name; 59 unsigned long rate; 60 struct clk *clk; 61 }; 62 63 struct lpss_private_data; 64 65 struct lpss_device_desc { 66 bool clk_required; 67 const char *clkdev_name; 68 bool ltr_required; 69 unsigned int prv_offset; 70 size_t prv_size_override; 71 bool clk_divider; 72 bool clk_gate; 73 bool save_ctx; 74 struct lpss_shared_clock *shared_clock; 75 void (*setup)(struct lpss_private_data *pdata); 76 }; 77 78 static struct lpss_device_desc lpss_dma_desc = { 79 .clk_required = true, 80 .clkdev_name = "hclk", 81 }; 82 83 struct lpss_private_data { 84 void __iomem *mmio_base; 85 resource_size_t mmio_size; 86 struct clk *clk; 87 const struct lpss_device_desc *dev_desc; 88 u32 prv_reg_ctx[LPSS_PRV_REG_COUNT]; 89 }; 90 91 static void lpss_uart_setup(struct lpss_private_data *pdata) 92 { 93 unsigned int offset; 94 u32 reg; 95 96 offset = pdata->dev_desc->prv_offset + LPSS_TX_INT; 97 reg = readl(pdata->mmio_base + offset); 98 writel(reg | LPSS_TX_INT_MASK, pdata->mmio_base + offset); 99 100 offset = pdata->dev_desc->prv_offset + LPSS_GENERAL; 101 reg = readl(pdata->mmio_base + offset); 102 writel(reg | LPSS_GENERAL_UART_RTS_OVRD, pdata->mmio_base + offset); 103 } 104 105 static void lpss_i2c_setup(struct lpss_private_data *pdata) 106 { 107 unsigned int offset; 108 u32 val; 109 110 offset = pdata->dev_desc->prv_offset + LPSS_RESETS; 111 val = readl(pdata->mmio_base + offset); 112 val |= LPSS_RESETS_RESET_APB | LPSS_RESETS_RESET_FUNC; 113 writel(val, pdata->mmio_base + offset); 114 } 115 116 static struct lpss_device_desc wpt_dev_desc = { 117 .clk_required = true, 118 .prv_offset = 0x800, 119 .ltr_required = true, 120 .clk_divider = true, 121 .clk_gate = true, 122 }; 123 124 static struct lpss_device_desc lpt_dev_desc = { 125 .clk_required = true, 126 .prv_offset = 0x800, 127 .ltr_required = true, 128 .clk_divider = true, 129 .clk_gate = true, 130 }; 131 132 static struct lpss_device_desc lpt_i2c_dev_desc = { 133 .clk_required = true, 134 .prv_offset = 0x800, 135 .ltr_required = true, 136 .clk_gate = true, 137 }; 138 139 static struct lpss_device_desc lpt_uart_dev_desc = { 140 .clk_required = true, 141 .prv_offset = 0x800, 142 .ltr_required = true, 143 .clk_divider = true, 144 .clk_gate = true, 145 .setup = lpss_uart_setup, 146 }; 147 148 static struct lpss_device_desc lpt_sdio_dev_desc = { 149 .prv_offset = 0x1000, 150 .prv_size_override = 0x1018, 151 .ltr_required = true, 152 }; 153 154 static struct lpss_shared_clock pwm_clock = { 155 .name = "pwm_clk", 156 .rate = 25000000, 157 }; 158 159 static struct lpss_device_desc byt_pwm_dev_desc = { 160 .clk_required = true, 161 .save_ctx = true, 162 .shared_clock = &pwm_clock, 163 }; 164 165 static struct lpss_device_desc byt_uart_dev_desc = { 166 .clk_required = true, 167 .prv_offset = 0x800, 168 .clk_divider = true, 169 .clk_gate = true, 170 .save_ctx = true, 171 .setup = lpss_uart_setup, 172 }; 173 174 static struct lpss_device_desc byt_spi_dev_desc = { 175 .clk_required = true, 176 .prv_offset = 0x400, 177 .clk_divider = true, 178 .clk_gate = true, 179 .save_ctx = true, 180 }; 181 182 static struct lpss_device_desc byt_sdio_dev_desc = { 183 .clk_required = true, 184 }; 185 186 static struct lpss_shared_clock i2c_clock = { 187 .name = "i2c_clk", 188 .rate = 100000000, 189 }; 190 191 static struct lpss_device_desc byt_i2c_dev_desc = { 192 .clk_required = true, 193 .prv_offset = 0x800, 194 .save_ctx = true, 195 .shared_clock = &i2c_clock, 196 .setup = lpss_i2c_setup, 197 }; 198 199 #else 200 201 #define LPSS_ADDR(desc) (0UL) 202 203 #endif /* CONFIG_X86_INTEL_LPSS */ 204 205 static const struct acpi_device_id acpi_lpss_device_ids[] = { 206 /* Generic LPSS devices */ 207 { "INTL9C60", LPSS_ADDR(lpss_dma_desc) }, 208 209 /* Lynxpoint LPSS devices */ 210 { "INT33C0", LPSS_ADDR(lpt_dev_desc) }, 211 { "INT33C1", LPSS_ADDR(lpt_dev_desc) }, 212 { "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) }, 213 { "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) }, 214 { "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) }, 215 { "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) }, 216 { "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) }, 217 { "INT33C7", }, 218 219 /* BayTrail LPSS devices */ 220 { "80860F09", LPSS_ADDR(byt_pwm_dev_desc) }, 221 { "80860F0A", LPSS_ADDR(byt_uart_dev_desc) }, 222 { "80860F0E", LPSS_ADDR(byt_spi_dev_desc) }, 223 { "80860F14", LPSS_ADDR(byt_sdio_dev_desc) }, 224 { "80860F41", LPSS_ADDR(byt_i2c_dev_desc) }, 225 { "INT33B2", }, 226 { "INT33FC", }, 227 228 { "INT3430", LPSS_ADDR(lpt_dev_desc) }, 229 { "INT3431", LPSS_ADDR(lpt_dev_desc) }, 230 { "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) }, 231 { "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) }, 232 { "INT3434", LPSS_ADDR(lpt_uart_dev_desc) }, 233 { "INT3435", LPSS_ADDR(lpt_uart_dev_desc) }, 234 { "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) }, 235 { "INT3437", }, 236 237 { "INT3438", LPSS_ADDR(wpt_dev_desc) }, 238 239 { } 240 }; 241 242 #ifdef CONFIG_X86_INTEL_LPSS 243 244 static int is_memory(struct acpi_resource *res, void *not_used) 245 { 246 struct resource r; 247 return !acpi_dev_resource_memory(res, &r); 248 } 249 250 /* LPSS main clock device. */ 251 static struct platform_device *lpss_clk_dev; 252 253 static inline void lpt_register_clock_device(void) 254 { 255 lpss_clk_dev = platform_device_register_simple("clk-lpt", -1, NULL, 0); 256 } 257 258 static int register_device_clock(struct acpi_device *adev, 259 struct lpss_private_data *pdata) 260 { 261 const struct lpss_device_desc *dev_desc = pdata->dev_desc; 262 struct lpss_shared_clock *shared_clock = dev_desc->shared_clock; 263 const char *devname = dev_name(&adev->dev); 264 struct clk *clk = ERR_PTR(-ENODEV); 265 struct lpss_clk_data *clk_data; 266 const char *parent, *clk_name; 267 void __iomem *prv_base; 268 269 if (!lpss_clk_dev) 270 lpt_register_clock_device(); 271 272 clk_data = platform_get_drvdata(lpss_clk_dev); 273 if (!clk_data) 274 return -ENODEV; 275 276 if (dev_desc->clkdev_name) { 277 clk_register_clkdev(clk_data->clk, dev_desc->clkdev_name, 278 devname); 279 return 0; 280 } 281 282 if (!pdata->mmio_base 283 || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE) 284 return -ENODATA; 285 286 parent = clk_data->name; 287 prv_base = pdata->mmio_base + dev_desc->prv_offset; 288 289 if (shared_clock) { 290 clk = shared_clock->clk; 291 if (!clk) { 292 clk = clk_register_fixed_rate(NULL, shared_clock->name, 293 "lpss_clk", 0, 294 shared_clock->rate); 295 shared_clock->clk = clk; 296 } 297 parent = shared_clock->name; 298 } 299 300 if (dev_desc->clk_gate) { 301 clk = clk_register_gate(NULL, devname, parent, 0, 302 prv_base, 0, 0, NULL); 303 parent = devname; 304 } 305 306 if (dev_desc->clk_divider) { 307 /* Prevent division by zero */ 308 if (!readl(prv_base)) 309 writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base); 310 311 clk_name = kasprintf(GFP_KERNEL, "%s-div", devname); 312 if (!clk_name) 313 return -ENOMEM; 314 clk = clk_register_fractional_divider(NULL, clk_name, parent, 315 0, prv_base, 316 1, 15, 16, 15, 0, NULL); 317 parent = clk_name; 318 319 clk_name = kasprintf(GFP_KERNEL, "%s-update", devname); 320 if (!clk_name) { 321 kfree(parent); 322 return -ENOMEM; 323 } 324 clk = clk_register_gate(NULL, clk_name, parent, 325 CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE, 326 prv_base, 31, 0, NULL); 327 kfree(parent); 328 kfree(clk_name); 329 } 330 331 if (IS_ERR(clk)) 332 return PTR_ERR(clk); 333 334 pdata->clk = clk; 335 clk_register_clkdev(clk, NULL, devname); 336 return 0; 337 } 338 339 static int acpi_lpss_create_device(struct acpi_device *adev, 340 const struct acpi_device_id *id) 341 { 342 struct lpss_device_desc *dev_desc; 343 struct lpss_private_data *pdata; 344 struct resource_list_entry *rentry; 345 struct list_head resource_list; 346 struct platform_device *pdev; 347 int ret; 348 349 dev_desc = (struct lpss_device_desc *)id->driver_data; 350 if (!dev_desc) { 351 pdev = acpi_create_platform_device(adev); 352 return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1; 353 } 354 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL); 355 if (!pdata) 356 return -ENOMEM; 357 358 INIT_LIST_HEAD(&resource_list); 359 ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL); 360 if (ret < 0) 361 goto err_out; 362 363 list_for_each_entry(rentry, &resource_list, node) 364 if (resource_type(&rentry->res) == IORESOURCE_MEM) { 365 if (dev_desc->prv_size_override) 366 pdata->mmio_size = dev_desc->prv_size_override; 367 else 368 pdata->mmio_size = resource_size(&rentry->res); 369 pdata->mmio_base = ioremap(rentry->res.start, 370 pdata->mmio_size); 371 break; 372 } 373 374 acpi_dev_free_resource_list(&resource_list); 375 376 pdata->dev_desc = dev_desc; 377 378 if (dev_desc->clk_required) { 379 ret = register_device_clock(adev, pdata); 380 if (ret) { 381 /* Skip the device, but continue the namespace scan. */ 382 ret = 0; 383 goto err_out; 384 } 385 } 386 387 /* 388 * This works around a known issue in ACPI tables where LPSS devices 389 * have _PS0 and _PS3 without _PSC (and no power resources), so 390 * acpi_bus_init_power() will assume that the BIOS has put them into D0. 391 */ 392 ret = acpi_device_fix_up_power(adev); 393 if (ret) { 394 /* Skip the device, but continue the namespace scan. */ 395 ret = 0; 396 goto err_out; 397 } 398 399 if (dev_desc->setup) 400 dev_desc->setup(pdata); 401 402 adev->driver_data = pdata; 403 pdev = acpi_create_platform_device(adev); 404 if (!IS_ERR_OR_NULL(pdev)) { 405 device_enable_async_suspend(&pdev->dev); 406 return 1; 407 } 408 409 ret = PTR_ERR(pdev); 410 adev->driver_data = NULL; 411 412 err_out: 413 kfree(pdata); 414 return ret; 415 } 416 417 static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg) 418 { 419 return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg); 420 } 421 422 static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata, 423 unsigned int reg) 424 { 425 writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg); 426 } 427 428 static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val) 429 { 430 struct acpi_device *adev; 431 struct lpss_private_data *pdata; 432 unsigned long flags; 433 int ret; 434 435 ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev); 436 if (WARN_ON(ret)) 437 return ret; 438 439 spin_lock_irqsave(&dev->power.lock, flags); 440 if (pm_runtime_suspended(dev)) { 441 ret = -EAGAIN; 442 goto out; 443 } 444 pdata = acpi_driver_data(adev); 445 if (WARN_ON(!pdata || !pdata->mmio_base)) { 446 ret = -ENODEV; 447 goto out; 448 } 449 *val = __lpss_reg_read(pdata, reg); 450 451 out: 452 spin_unlock_irqrestore(&dev->power.lock, flags); 453 return ret; 454 } 455 456 static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr, 457 char *buf) 458 { 459 u32 ltr_value = 0; 460 unsigned int reg; 461 int ret; 462 463 reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR; 464 ret = lpss_reg_read(dev, reg, <r_value); 465 if (ret) 466 return ret; 467 468 return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value); 469 } 470 471 static ssize_t lpss_ltr_mode_show(struct device *dev, 472 struct device_attribute *attr, char *buf) 473 { 474 u32 ltr_mode = 0; 475 char *outstr; 476 int ret; 477 478 ret = lpss_reg_read(dev, LPSS_GENERAL, <r_mode); 479 if (ret) 480 return ret; 481 482 outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto"; 483 return sprintf(buf, "%s\n", outstr); 484 } 485 486 static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL); 487 static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL); 488 static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL); 489 490 static struct attribute *lpss_attrs[] = { 491 &dev_attr_auto_ltr.attr, 492 &dev_attr_sw_ltr.attr, 493 &dev_attr_ltr_mode.attr, 494 NULL, 495 }; 496 497 static struct attribute_group lpss_attr_group = { 498 .attrs = lpss_attrs, 499 .name = "lpss_ltr", 500 }; 501 502 static void acpi_lpss_set_ltr(struct device *dev, s32 val) 503 { 504 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 505 u32 ltr_mode, ltr_val; 506 507 ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL); 508 if (val < 0) { 509 if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) { 510 ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW; 511 __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL); 512 } 513 return; 514 } 515 ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK; 516 if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) { 517 ltr_val |= LPSS_LTR_SNOOP_LAT_32US; 518 val = LPSS_LTR_MAX_VAL; 519 } else if (val > LPSS_LTR_MAX_VAL) { 520 ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ; 521 val >>= LPSS_LTR_SNOOP_LAT_SHIFT; 522 } else { 523 ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ; 524 } 525 ltr_val |= val; 526 __lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR); 527 if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) { 528 ltr_mode |= LPSS_GENERAL_LTR_MODE_SW; 529 __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL); 530 } 531 } 532 533 #ifdef CONFIG_PM 534 /** 535 * acpi_lpss_save_ctx() - Save the private registers of LPSS device 536 * @dev: LPSS device 537 * 538 * Most LPSS devices have private registers which may loose their context when 539 * the device is powered down. acpi_lpss_save_ctx() saves those registers into 540 * prv_reg_ctx array. 541 */ 542 static void acpi_lpss_save_ctx(struct device *dev) 543 { 544 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 545 unsigned int i; 546 547 for (i = 0; i < LPSS_PRV_REG_COUNT; i++) { 548 unsigned long offset = i * sizeof(u32); 549 550 pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset); 551 dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n", 552 pdata->prv_reg_ctx[i], offset); 553 } 554 } 555 556 /** 557 * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device 558 * @dev: LPSS device 559 * 560 * Restores the registers that were previously stored with acpi_lpss_save_ctx(). 561 */ 562 static void acpi_lpss_restore_ctx(struct device *dev) 563 { 564 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 565 unsigned int i; 566 567 /* 568 * The following delay is needed or the subsequent write operations may 569 * fail. The LPSS devices are actually PCI devices and the PCI spec 570 * expects 10ms delay before the device can be accessed after D3 to D0 571 * transition. 572 */ 573 msleep(10); 574 575 for (i = 0; i < LPSS_PRV_REG_COUNT; i++) { 576 unsigned long offset = i * sizeof(u32); 577 578 __lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset); 579 dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n", 580 pdata->prv_reg_ctx[i], offset); 581 } 582 } 583 584 #ifdef CONFIG_PM_SLEEP 585 static int acpi_lpss_suspend_late(struct device *dev) 586 { 587 int ret = pm_generic_suspend_late(dev); 588 589 if (ret) 590 return ret; 591 592 acpi_lpss_save_ctx(dev); 593 return acpi_dev_suspend_late(dev); 594 } 595 596 static int acpi_lpss_restore_early(struct device *dev) 597 { 598 int ret = acpi_dev_resume_early(dev); 599 600 if (ret) 601 return ret; 602 603 acpi_lpss_restore_ctx(dev); 604 return pm_generic_resume_early(dev); 605 } 606 #endif /* CONFIG_PM_SLEEP */ 607 608 #ifdef CONFIG_PM_RUNTIME 609 static int acpi_lpss_runtime_suspend(struct device *dev) 610 { 611 int ret = pm_generic_runtime_suspend(dev); 612 613 if (ret) 614 return ret; 615 616 acpi_lpss_save_ctx(dev); 617 return acpi_dev_runtime_suspend(dev); 618 } 619 620 static int acpi_lpss_runtime_resume(struct device *dev) 621 { 622 int ret = acpi_dev_runtime_resume(dev); 623 624 if (ret) 625 return ret; 626 627 acpi_lpss_restore_ctx(dev); 628 return pm_generic_runtime_resume(dev); 629 } 630 #endif /* CONFIG_PM_RUNTIME */ 631 #endif /* CONFIG_PM */ 632 633 static struct dev_pm_domain acpi_lpss_pm_domain = { 634 .ops = { 635 #ifdef CONFIG_PM_SLEEP 636 .suspend_late = acpi_lpss_suspend_late, 637 .restore_early = acpi_lpss_restore_early, 638 .prepare = acpi_subsys_prepare, 639 .complete = acpi_subsys_complete, 640 .suspend = acpi_subsys_suspend, 641 .resume_early = acpi_subsys_resume_early, 642 .freeze = acpi_subsys_freeze, 643 .poweroff = acpi_subsys_suspend, 644 .poweroff_late = acpi_subsys_suspend_late, 645 #endif 646 #ifdef CONFIG_PM_RUNTIME 647 .runtime_suspend = acpi_lpss_runtime_suspend, 648 .runtime_resume = acpi_lpss_runtime_resume, 649 #endif 650 }, 651 }; 652 653 static int acpi_lpss_platform_notify(struct notifier_block *nb, 654 unsigned long action, void *data) 655 { 656 struct platform_device *pdev = to_platform_device(data); 657 struct lpss_private_data *pdata; 658 struct acpi_device *adev; 659 const struct acpi_device_id *id; 660 661 id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev); 662 if (!id || !id->driver_data) 663 return 0; 664 665 if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev)) 666 return 0; 667 668 pdata = acpi_driver_data(adev); 669 if (!pdata || !pdata->mmio_base) 670 return 0; 671 672 if (pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) { 673 dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n"); 674 return 0; 675 } 676 677 switch (action) { 678 case BUS_NOTIFY_BOUND_DRIVER: 679 if (pdata->dev_desc->save_ctx) 680 pdev->dev.pm_domain = &acpi_lpss_pm_domain; 681 break; 682 case BUS_NOTIFY_UNBOUND_DRIVER: 683 if (pdata->dev_desc->save_ctx) 684 pdev->dev.pm_domain = NULL; 685 break; 686 case BUS_NOTIFY_ADD_DEVICE: 687 if (pdata->dev_desc->ltr_required) 688 return sysfs_create_group(&pdev->dev.kobj, 689 &lpss_attr_group); 690 case BUS_NOTIFY_DEL_DEVICE: 691 if (pdata->dev_desc->ltr_required) 692 sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group); 693 default: 694 break; 695 } 696 697 return 0; 698 } 699 700 static struct notifier_block acpi_lpss_nb = { 701 .notifier_call = acpi_lpss_platform_notify, 702 }; 703 704 static void acpi_lpss_bind(struct device *dev) 705 { 706 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 707 708 if (!pdata || !pdata->mmio_base || !pdata->dev_desc->ltr_required) 709 return; 710 711 if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) 712 dev->power.set_latency_tolerance = acpi_lpss_set_ltr; 713 else 714 dev_err(dev, "MMIO size insufficient to access LTR\n"); 715 } 716 717 static void acpi_lpss_unbind(struct device *dev) 718 { 719 dev->power.set_latency_tolerance = NULL; 720 } 721 722 static struct acpi_scan_handler lpss_handler = { 723 .ids = acpi_lpss_device_ids, 724 .attach = acpi_lpss_create_device, 725 .bind = acpi_lpss_bind, 726 .unbind = acpi_lpss_unbind, 727 }; 728 729 void __init acpi_lpss_init(void) 730 { 731 if (!lpt_clk_init()) { 732 bus_register_notifier(&platform_bus_type, &acpi_lpss_nb); 733 acpi_scan_add_handler(&lpss_handler); 734 } 735 } 736 737 #else 738 739 static struct acpi_scan_handler lpss_handler = { 740 .ids = acpi_lpss_device_ids, 741 }; 742 743 void __init acpi_lpss_init(void) 744 { 745 acpi_scan_add_handler(&lpss_handler); 746 } 747 748 #endif /* CONFIG_X86_INTEL_LPSS */ 749