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/clkdev.h> 15 #include <linux/clk-provider.h> 16 #include <linux/err.h> 17 #include <linux/io.h> 18 #include <linux/mutex.h> 19 #include <linux/pci.h> 20 #include <linux/platform_device.h> 21 #include <linux/platform_data/clk-lpss.h> 22 #include <linux/platform_data/x86/pmc_atom.h> 23 #include <linux/pm_domain.h> 24 #include <linux/pm_runtime.h> 25 #include <linux/pwm.h> 26 #include <linux/suspend.h> 27 #include <linux/delay.h> 28 29 #include "internal.h" 30 31 ACPI_MODULE_NAME("acpi_lpss"); 32 33 #ifdef CONFIG_X86_INTEL_LPSS 34 35 #include <asm/cpu_device_id.h> 36 #include <asm/intel-family.h> 37 #include <asm/iosf_mbi.h> 38 39 #define LPSS_ADDR(desc) ((unsigned long)&desc) 40 41 #define LPSS_CLK_SIZE 0x04 42 #define LPSS_LTR_SIZE 0x18 43 44 /* Offsets relative to LPSS_PRIVATE_OFFSET */ 45 #define LPSS_CLK_DIVIDER_DEF_MASK (BIT(1) | BIT(16)) 46 #define LPSS_RESETS 0x04 47 #define LPSS_RESETS_RESET_FUNC BIT(0) 48 #define LPSS_RESETS_RESET_APB BIT(1) 49 #define LPSS_GENERAL 0x08 50 #define LPSS_GENERAL_LTR_MODE_SW BIT(2) 51 #define LPSS_GENERAL_UART_RTS_OVRD BIT(3) 52 #define LPSS_SW_LTR 0x10 53 #define LPSS_AUTO_LTR 0x14 54 #define LPSS_LTR_SNOOP_REQ BIT(15) 55 #define LPSS_LTR_SNOOP_MASK 0x0000FFFF 56 #define LPSS_LTR_SNOOP_LAT_1US 0x800 57 #define LPSS_LTR_SNOOP_LAT_32US 0xC00 58 #define LPSS_LTR_SNOOP_LAT_SHIFT 5 59 #define LPSS_LTR_SNOOP_LAT_CUTOFF 3000 60 #define LPSS_LTR_MAX_VAL 0x3FF 61 #define LPSS_TX_INT 0x20 62 #define LPSS_TX_INT_MASK BIT(1) 63 64 #define LPSS_PRV_REG_COUNT 9 65 66 /* LPSS Flags */ 67 #define LPSS_CLK BIT(0) 68 #define LPSS_CLK_GATE BIT(1) 69 #define LPSS_CLK_DIVIDER BIT(2) 70 #define LPSS_LTR BIT(3) 71 #define LPSS_SAVE_CTX BIT(4) 72 #define LPSS_NO_D3_DELAY BIT(5) 73 74 /* Crystal Cove PMIC shares same ACPI ID between different platforms */ 75 #define BYT_CRC_HRV 2 76 #define CHT_CRC_HRV 3 77 78 struct lpss_private_data; 79 80 struct lpss_device_desc { 81 unsigned int flags; 82 const char *clk_con_id; 83 unsigned int prv_offset; 84 size_t prv_size_override; 85 struct property_entry *properties; 86 void (*setup)(struct lpss_private_data *pdata); 87 bool resume_from_noirq; 88 }; 89 90 static const struct lpss_device_desc lpss_dma_desc = { 91 .flags = LPSS_CLK, 92 }; 93 94 struct lpss_private_data { 95 struct acpi_device *adev; 96 void __iomem *mmio_base; 97 resource_size_t mmio_size; 98 unsigned int fixed_clk_rate; 99 struct clk *clk; 100 const struct lpss_device_desc *dev_desc; 101 u32 prv_reg_ctx[LPSS_PRV_REG_COUNT]; 102 }; 103 104 /* Devices which need to be in D3 before lpss_iosf_enter_d3_state() proceeds */ 105 static u32 pmc_atom_d3_mask = 0xfe000ffe; 106 107 /* LPSS run time quirks */ 108 static unsigned int lpss_quirks; 109 110 /* 111 * LPSS_QUIRK_ALWAYS_POWER_ON: override power state for LPSS DMA device. 112 * 113 * The LPSS DMA controller has neither _PS0 nor _PS3 method. Moreover 114 * it can be powered off automatically whenever the last LPSS device goes down. 115 * In case of no power any access to the DMA controller will hang the system. 116 * The behaviour is reproduced on some HP laptops based on Intel BayTrail as 117 * well as on ASuS T100TA transformer. 118 * 119 * This quirk overrides power state of entire LPSS island to keep DMA powered 120 * on whenever we have at least one other device in use. 121 */ 122 #define LPSS_QUIRK_ALWAYS_POWER_ON BIT(0) 123 124 /* UART Component Parameter Register */ 125 #define LPSS_UART_CPR 0xF4 126 #define LPSS_UART_CPR_AFCE BIT(4) 127 128 static void lpss_uart_setup(struct lpss_private_data *pdata) 129 { 130 unsigned int offset; 131 u32 val; 132 133 offset = pdata->dev_desc->prv_offset + LPSS_TX_INT; 134 val = readl(pdata->mmio_base + offset); 135 writel(val | LPSS_TX_INT_MASK, pdata->mmio_base + offset); 136 137 val = readl(pdata->mmio_base + LPSS_UART_CPR); 138 if (!(val & LPSS_UART_CPR_AFCE)) { 139 offset = pdata->dev_desc->prv_offset + LPSS_GENERAL; 140 val = readl(pdata->mmio_base + offset); 141 val |= LPSS_GENERAL_UART_RTS_OVRD; 142 writel(val, pdata->mmio_base + offset); 143 } 144 } 145 146 static void lpss_deassert_reset(struct lpss_private_data *pdata) 147 { 148 unsigned int offset; 149 u32 val; 150 151 offset = pdata->dev_desc->prv_offset + LPSS_RESETS; 152 val = readl(pdata->mmio_base + offset); 153 val |= LPSS_RESETS_RESET_APB | LPSS_RESETS_RESET_FUNC; 154 writel(val, pdata->mmio_base + offset); 155 } 156 157 /* 158 * BYT PWM used for backlight control by the i915 driver on systems without 159 * the Crystal Cove PMIC. 160 */ 161 static struct pwm_lookup byt_pwm_lookup[] = { 162 PWM_LOOKUP_WITH_MODULE("80860F09:00", 0, "0000:00:02.0", 163 "pwm_backlight", 0, PWM_POLARITY_NORMAL, 164 "pwm-lpss-platform"), 165 }; 166 167 static void byt_pwm_setup(struct lpss_private_data *pdata) 168 { 169 struct acpi_device *adev = pdata->adev; 170 171 /* Only call pwm_add_table for the first PWM controller */ 172 if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "1")) 173 return; 174 175 if (!acpi_dev_present("INT33FD", NULL, BYT_CRC_HRV)) 176 pwm_add_table(byt_pwm_lookup, ARRAY_SIZE(byt_pwm_lookup)); 177 } 178 179 #define LPSS_I2C_ENABLE 0x6c 180 181 static void byt_i2c_setup(struct lpss_private_data *pdata) 182 { 183 const char *uid_str = acpi_device_uid(pdata->adev); 184 acpi_handle handle = pdata->adev->handle; 185 unsigned long long shared_host = 0; 186 acpi_status status; 187 long uid = 0; 188 189 /* Expected to always be true, but better safe then sorry */ 190 if (uid_str) 191 uid = simple_strtol(uid_str, NULL, 10); 192 193 /* Detect I2C bus shared with PUNIT and ignore its d3 status */ 194 status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host); 195 if (ACPI_SUCCESS(status) && shared_host && uid) 196 pmc_atom_d3_mask &= ~(BIT_LPSS2_F1_I2C1 << (uid - 1)); 197 198 lpss_deassert_reset(pdata); 199 200 if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset)) 201 pdata->fixed_clk_rate = 133000000; 202 203 writel(0, pdata->mmio_base + LPSS_I2C_ENABLE); 204 } 205 206 /* BSW PWM used for backlight control by the i915 driver */ 207 static struct pwm_lookup bsw_pwm_lookup[] = { 208 PWM_LOOKUP_WITH_MODULE("80862288:00", 0, "0000:00:02.0", 209 "pwm_backlight", 0, PWM_POLARITY_NORMAL, 210 "pwm-lpss-platform"), 211 }; 212 213 static void bsw_pwm_setup(struct lpss_private_data *pdata) 214 { 215 struct acpi_device *adev = pdata->adev; 216 217 /* Only call pwm_add_table for the first PWM controller */ 218 if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "1")) 219 return; 220 221 pwm_add_table(bsw_pwm_lookup, ARRAY_SIZE(bsw_pwm_lookup)); 222 } 223 224 static const struct lpss_device_desc lpt_dev_desc = { 225 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR, 226 .prv_offset = 0x800, 227 }; 228 229 static const struct lpss_device_desc lpt_i2c_dev_desc = { 230 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR, 231 .prv_offset = 0x800, 232 }; 233 234 static struct property_entry uart_properties[] = { 235 PROPERTY_ENTRY_U32("reg-io-width", 4), 236 PROPERTY_ENTRY_U32("reg-shift", 2), 237 PROPERTY_ENTRY_BOOL("snps,uart-16550-compatible"), 238 { }, 239 }; 240 241 static const struct lpss_device_desc lpt_uart_dev_desc = { 242 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR, 243 .clk_con_id = "baudclk", 244 .prv_offset = 0x800, 245 .setup = lpss_uart_setup, 246 .properties = uart_properties, 247 }; 248 249 static const struct lpss_device_desc lpt_sdio_dev_desc = { 250 .flags = LPSS_LTR, 251 .prv_offset = 0x1000, 252 .prv_size_override = 0x1018, 253 }; 254 255 static const struct lpss_device_desc byt_pwm_dev_desc = { 256 .flags = LPSS_SAVE_CTX, 257 .prv_offset = 0x800, 258 .setup = byt_pwm_setup, 259 }; 260 261 static const struct lpss_device_desc bsw_pwm_dev_desc = { 262 .flags = LPSS_SAVE_CTX | LPSS_NO_D3_DELAY, 263 .prv_offset = 0x800, 264 .setup = bsw_pwm_setup, 265 }; 266 267 static const struct lpss_device_desc byt_uart_dev_desc = { 268 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX, 269 .clk_con_id = "baudclk", 270 .prv_offset = 0x800, 271 .setup = lpss_uart_setup, 272 .properties = uart_properties, 273 }; 274 275 static const struct lpss_device_desc bsw_uart_dev_desc = { 276 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX 277 | LPSS_NO_D3_DELAY, 278 .clk_con_id = "baudclk", 279 .prv_offset = 0x800, 280 .setup = lpss_uart_setup, 281 .properties = uart_properties, 282 }; 283 284 static const struct lpss_device_desc byt_spi_dev_desc = { 285 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX, 286 .prv_offset = 0x400, 287 }; 288 289 static const struct lpss_device_desc byt_sdio_dev_desc = { 290 .flags = LPSS_CLK, 291 }; 292 293 static const struct lpss_device_desc byt_i2c_dev_desc = { 294 .flags = LPSS_CLK | LPSS_SAVE_CTX, 295 .prv_offset = 0x800, 296 .setup = byt_i2c_setup, 297 .resume_from_noirq = true, 298 }; 299 300 static const struct lpss_device_desc bsw_i2c_dev_desc = { 301 .flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY, 302 .prv_offset = 0x800, 303 .setup = byt_i2c_setup, 304 .resume_from_noirq = true, 305 }; 306 307 static const struct lpss_device_desc bsw_spi_dev_desc = { 308 .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX 309 | LPSS_NO_D3_DELAY, 310 .prv_offset = 0x400, 311 .setup = lpss_deassert_reset, 312 }; 313 314 #define ICPU(model) { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, } 315 316 static const struct x86_cpu_id lpss_cpu_ids[] = { 317 ICPU(INTEL_FAM6_ATOM_SILVERMONT), /* Valleyview, Bay Trail */ 318 ICPU(INTEL_FAM6_ATOM_AIRMONT), /* Braswell, Cherry Trail */ 319 {} 320 }; 321 322 #else 323 324 #define LPSS_ADDR(desc) (0UL) 325 326 #endif /* CONFIG_X86_INTEL_LPSS */ 327 328 static const struct acpi_device_id acpi_lpss_device_ids[] = { 329 /* Generic LPSS devices */ 330 { "INTL9C60", LPSS_ADDR(lpss_dma_desc) }, 331 332 /* Lynxpoint LPSS devices */ 333 { "INT33C0", LPSS_ADDR(lpt_dev_desc) }, 334 { "INT33C1", LPSS_ADDR(lpt_dev_desc) }, 335 { "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) }, 336 { "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) }, 337 { "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) }, 338 { "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) }, 339 { "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) }, 340 { "INT33C7", }, 341 342 /* BayTrail LPSS devices */ 343 { "80860F09", LPSS_ADDR(byt_pwm_dev_desc) }, 344 { "80860F0A", LPSS_ADDR(byt_uart_dev_desc) }, 345 { "80860F0E", LPSS_ADDR(byt_spi_dev_desc) }, 346 { "80860F14", LPSS_ADDR(byt_sdio_dev_desc) }, 347 { "80860F41", LPSS_ADDR(byt_i2c_dev_desc) }, 348 { "INT33B2", }, 349 { "INT33FC", }, 350 351 /* Braswell LPSS devices */ 352 { "80862286", LPSS_ADDR(lpss_dma_desc) }, 353 { "80862288", LPSS_ADDR(bsw_pwm_dev_desc) }, 354 { "8086228A", LPSS_ADDR(bsw_uart_dev_desc) }, 355 { "8086228E", LPSS_ADDR(bsw_spi_dev_desc) }, 356 { "808622C0", LPSS_ADDR(lpss_dma_desc) }, 357 { "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) }, 358 359 /* Broadwell LPSS devices */ 360 { "INT3430", LPSS_ADDR(lpt_dev_desc) }, 361 { "INT3431", LPSS_ADDR(lpt_dev_desc) }, 362 { "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) }, 363 { "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) }, 364 { "INT3434", LPSS_ADDR(lpt_uart_dev_desc) }, 365 { "INT3435", LPSS_ADDR(lpt_uart_dev_desc) }, 366 { "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) }, 367 { "INT3437", }, 368 369 /* Wildcat Point LPSS devices */ 370 { "INT3438", LPSS_ADDR(lpt_dev_desc) }, 371 372 { } 373 }; 374 375 #ifdef CONFIG_X86_INTEL_LPSS 376 377 static int is_memory(struct acpi_resource *res, void *not_used) 378 { 379 struct resource r; 380 return !acpi_dev_resource_memory(res, &r); 381 } 382 383 /* LPSS main clock device. */ 384 static struct platform_device *lpss_clk_dev; 385 386 static inline void lpt_register_clock_device(void) 387 { 388 lpss_clk_dev = platform_device_register_simple("clk-lpt", -1, NULL, 0); 389 } 390 391 static int register_device_clock(struct acpi_device *adev, 392 struct lpss_private_data *pdata) 393 { 394 const struct lpss_device_desc *dev_desc = pdata->dev_desc; 395 const char *devname = dev_name(&adev->dev); 396 struct clk *clk; 397 struct lpss_clk_data *clk_data; 398 const char *parent, *clk_name; 399 void __iomem *prv_base; 400 401 if (!lpss_clk_dev) 402 lpt_register_clock_device(); 403 404 clk_data = platform_get_drvdata(lpss_clk_dev); 405 if (!clk_data) 406 return -ENODEV; 407 clk = clk_data->clk; 408 409 if (!pdata->mmio_base 410 || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE) 411 return -ENODATA; 412 413 parent = clk_data->name; 414 prv_base = pdata->mmio_base + dev_desc->prv_offset; 415 416 if (pdata->fixed_clk_rate) { 417 clk = clk_register_fixed_rate(NULL, devname, parent, 0, 418 pdata->fixed_clk_rate); 419 goto out; 420 } 421 422 if (dev_desc->flags & LPSS_CLK_GATE) { 423 clk = clk_register_gate(NULL, devname, parent, 0, 424 prv_base, 0, 0, NULL); 425 parent = devname; 426 } 427 428 if (dev_desc->flags & LPSS_CLK_DIVIDER) { 429 /* Prevent division by zero */ 430 if (!readl(prv_base)) 431 writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base); 432 433 clk_name = kasprintf(GFP_KERNEL, "%s-div", devname); 434 if (!clk_name) 435 return -ENOMEM; 436 clk = clk_register_fractional_divider(NULL, clk_name, parent, 437 0, prv_base, 438 1, 15, 16, 15, 0, NULL); 439 parent = clk_name; 440 441 clk_name = kasprintf(GFP_KERNEL, "%s-update", devname); 442 if (!clk_name) { 443 kfree(parent); 444 return -ENOMEM; 445 } 446 clk = clk_register_gate(NULL, clk_name, parent, 447 CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE, 448 prv_base, 31, 0, NULL); 449 kfree(parent); 450 kfree(clk_name); 451 } 452 out: 453 if (IS_ERR(clk)) 454 return PTR_ERR(clk); 455 456 pdata->clk = clk; 457 clk_register_clkdev(clk, dev_desc->clk_con_id, devname); 458 return 0; 459 } 460 461 struct lpss_device_links { 462 const char *supplier_hid; 463 const char *supplier_uid; 464 const char *consumer_hid; 465 const char *consumer_uid; 466 u32 flags; 467 }; 468 469 /* 470 * The _DEP method is used to identify dependencies but instead of creating 471 * device links for every handle in _DEP, only links in the following list are 472 * created. That is necessary because, in the general case, _DEP can refer to 473 * devices that might not have drivers, or that are on different buses, or where 474 * the supplier is not enumerated until after the consumer is probed. 475 */ 476 static const struct lpss_device_links lpss_device_links[] = { 477 {"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME}, 478 {"808622C1", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME}, 479 {"80860F41", "5", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME}, 480 }; 481 482 static bool hid_uid_match(struct acpi_device *adev, 483 const char *hid2, const char *uid2) 484 { 485 const char *hid1 = acpi_device_hid(adev); 486 const char *uid1 = acpi_device_uid(adev); 487 488 if (strcmp(hid1, hid2)) 489 return false; 490 491 if (!uid2) 492 return true; 493 494 return uid1 && !strcmp(uid1, uid2); 495 } 496 497 static bool acpi_lpss_is_supplier(struct acpi_device *adev, 498 const struct lpss_device_links *link) 499 { 500 return hid_uid_match(adev, link->supplier_hid, link->supplier_uid); 501 } 502 503 static bool acpi_lpss_is_consumer(struct acpi_device *adev, 504 const struct lpss_device_links *link) 505 { 506 return hid_uid_match(adev, link->consumer_hid, link->consumer_uid); 507 } 508 509 struct hid_uid { 510 const char *hid; 511 const char *uid; 512 }; 513 514 static int match_hid_uid(struct device *dev, void *data) 515 { 516 struct acpi_device *adev = ACPI_COMPANION(dev); 517 struct hid_uid *id = data; 518 519 if (!adev) 520 return 0; 521 522 return hid_uid_match(adev, id->hid, id->uid); 523 } 524 525 static struct device *acpi_lpss_find_device(const char *hid, const char *uid) 526 { 527 struct device *dev; 528 529 struct hid_uid data = { 530 .hid = hid, 531 .uid = uid, 532 }; 533 534 dev = bus_find_device(&platform_bus_type, NULL, &data, match_hid_uid); 535 if (dev) 536 return dev; 537 538 return bus_find_device(&pci_bus_type, NULL, &data, match_hid_uid); 539 } 540 541 static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle) 542 { 543 struct acpi_handle_list dep_devices; 544 acpi_status status; 545 int i; 546 547 if (!acpi_has_method(adev->handle, "_DEP")) 548 return false; 549 550 status = acpi_evaluate_reference(adev->handle, "_DEP", NULL, 551 &dep_devices); 552 if (ACPI_FAILURE(status)) { 553 dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n"); 554 return false; 555 } 556 557 for (i = 0; i < dep_devices.count; i++) { 558 if (dep_devices.handles[i] == handle) 559 return true; 560 } 561 562 return false; 563 } 564 565 static void acpi_lpss_link_consumer(struct device *dev1, 566 const struct lpss_device_links *link) 567 { 568 struct device *dev2; 569 570 dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid); 571 if (!dev2) 572 return; 573 574 if (acpi_lpss_dep(ACPI_COMPANION(dev2), ACPI_HANDLE(dev1))) 575 device_link_add(dev2, dev1, link->flags); 576 577 put_device(dev2); 578 } 579 580 static void acpi_lpss_link_supplier(struct device *dev1, 581 const struct lpss_device_links *link) 582 { 583 struct device *dev2; 584 585 dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid); 586 if (!dev2) 587 return; 588 589 if (acpi_lpss_dep(ACPI_COMPANION(dev1), ACPI_HANDLE(dev2))) 590 device_link_add(dev1, dev2, link->flags); 591 592 put_device(dev2); 593 } 594 595 static void acpi_lpss_create_device_links(struct acpi_device *adev, 596 struct platform_device *pdev) 597 { 598 int i; 599 600 for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) { 601 const struct lpss_device_links *link = &lpss_device_links[i]; 602 603 if (acpi_lpss_is_supplier(adev, link)) 604 acpi_lpss_link_consumer(&pdev->dev, link); 605 606 if (acpi_lpss_is_consumer(adev, link)) 607 acpi_lpss_link_supplier(&pdev->dev, link); 608 } 609 } 610 611 static int acpi_lpss_create_device(struct acpi_device *adev, 612 const struct acpi_device_id *id) 613 { 614 const struct lpss_device_desc *dev_desc; 615 struct lpss_private_data *pdata; 616 struct resource_entry *rentry; 617 struct list_head resource_list; 618 struct platform_device *pdev; 619 int ret; 620 621 dev_desc = (const struct lpss_device_desc *)id->driver_data; 622 if (!dev_desc) { 623 pdev = acpi_create_platform_device(adev, NULL); 624 return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1; 625 } 626 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL); 627 if (!pdata) 628 return -ENOMEM; 629 630 INIT_LIST_HEAD(&resource_list); 631 ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL); 632 if (ret < 0) 633 goto err_out; 634 635 list_for_each_entry(rentry, &resource_list, node) 636 if (resource_type(rentry->res) == IORESOURCE_MEM) { 637 if (dev_desc->prv_size_override) 638 pdata->mmio_size = dev_desc->prv_size_override; 639 else 640 pdata->mmio_size = resource_size(rentry->res); 641 pdata->mmio_base = ioremap(rentry->res->start, 642 pdata->mmio_size); 643 break; 644 } 645 646 acpi_dev_free_resource_list(&resource_list); 647 648 if (!pdata->mmio_base) { 649 /* Avoid acpi_bus_attach() instantiating a pdev for this dev. */ 650 adev->pnp.type.platform_id = 0; 651 /* Skip the device, but continue the namespace scan. */ 652 ret = 0; 653 goto err_out; 654 } 655 656 pdata->adev = adev; 657 pdata->dev_desc = dev_desc; 658 659 if (dev_desc->setup) 660 dev_desc->setup(pdata); 661 662 if (dev_desc->flags & LPSS_CLK) { 663 ret = register_device_clock(adev, pdata); 664 if (ret) { 665 /* Skip the device, but continue the namespace scan. */ 666 ret = 0; 667 goto err_out; 668 } 669 } 670 671 /* 672 * This works around a known issue in ACPI tables where LPSS devices 673 * have _PS0 and _PS3 without _PSC (and no power resources), so 674 * acpi_bus_init_power() will assume that the BIOS has put them into D0. 675 */ 676 ret = acpi_device_fix_up_power(adev); 677 if (ret) { 678 /* Skip the device, but continue the namespace scan. */ 679 ret = 0; 680 goto err_out; 681 } 682 683 adev->driver_data = pdata; 684 pdev = acpi_create_platform_device(adev, dev_desc->properties); 685 if (!IS_ERR_OR_NULL(pdev)) { 686 acpi_lpss_create_device_links(adev, pdev); 687 return 1; 688 } 689 690 ret = PTR_ERR(pdev); 691 adev->driver_data = NULL; 692 693 err_out: 694 kfree(pdata); 695 return ret; 696 } 697 698 static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg) 699 { 700 return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg); 701 } 702 703 static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata, 704 unsigned int reg) 705 { 706 writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg); 707 } 708 709 static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val) 710 { 711 struct acpi_device *adev; 712 struct lpss_private_data *pdata; 713 unsigned long flags; 714 int ret; 715 716 ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev); 717 if (WARN_ON(ret)) 718 return ret; 719 720 spin_lock_irqsave(&dev->power.lock, flags); 721 if (pm_runtime_suspended(dev)) { 722 ret = -EAGAIN; 723 goto out; 724 } 725 pdata = acpi_driver_data(adev); 726 if (WARN_ON(!pdata || !pdata->mmio_base)) { 727 ret = -ENODEV; 728 goto out; 729 } 730 *val = __lpss_reg_read(pdata, reg); 731 732 out: 733 spin_unlock_irqrestore(&dev->power.lock, flags); 734 return ret; 735 } 736 737 static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr, 738 char *buf) 739 { 740 u32 ltr_value = 0; 741 unsigned int reg; 742 int ret; 743 744 reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR; 745 ret = lpss_reg_read(dev, reg, <r_value); 746 if (ret) 747 return ret; 748 749 return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value); 750 } 751 752 static ssize_t lpss_ltr_mode_show(struct device *dev, 753 struct device_attribute *attr, char *buf) 754 { 755 u32 ltr_mode = 0; 756 char *outstr; 757 int ret; 758 759 ret = lpss_reg_read(dev, LPSS_GENERAL, <r_mode); 760 if (ret) 761 return ret; 762 763 outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto"; 764 return sprintf(buf, "%s\n", outstr); 765 } 766 767 static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL); 768 static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL); 769 static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL); 770 771 static struct attribute *lpss_attrs[] = { 772 &dev_attr_auto_ltr.attr, 773 &dev_attr_sw_ltr.attr, 774 &dev_attr_ltr_mode.attr, 775 NULL, 776 }; 777 778 static const struct attribute_group lpss_attr_group = { 779 .attrs = lpss_attrs, 780 .name = "lpss_ltr", 781 }; 782 783 static void acpi_lpss_set_ltr(struct device *dev, s32 val) 784 { 785 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 786 u32 ltr_mode, ltr_val; 787 788 ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL); 789 if (val < 0) { 790 if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) { 791 ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW; 792 __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL); 793 } 794 return; 795 } 796 ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK; 797 if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) { 798 ltr_val |= LPSS_LTR_SNOOP_LAT_32US; 799 val = LPSS_LTR_MAX_VAL; 800 } else if (val > LPSS_LTR_MAX_VAL) { 801 ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ; 802 val >>= LPSS_LTR_SNOOP_LAT_SHIFT; 803 } else { 804 ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ; 805 } 806 ltr_val |= val; 807 __lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR); 808 if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) { 809 ltr_mode |= LPSS_GENERAL_LTR_MODE_SW; 810 __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL); 811 } 812 } 813 814 #ifdef CONFIG_PM 815 /** 816 * acpi_lpss_save_ctx() - Save the private registers of LPSS device 817 * @dev: LPSS device 818 * @pdata: pointer to the private data of the LPSS device 819 * 820 * Most LPSS devices have private registers which may loose their context when 821 * the device is powered down. acpi_lpss_save_ctx() saves those registers into 822 * prv_reg_ctx array. 823 */ 824 static void acpi_lpss_save_ctx(struct device *dev, 825 struct lpss_private_data *pdata) 826 { 827 unsigned int i; 828 829 for (i = 0; i < LPSS_PRV_REG_COUNT; i++) { 830 unsigned long offset = i * sizeof(u32); 831 832 pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset); 833 dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n", 834 pdata->prv_reg_ctx[i], offset); 835 } 836 } 837 838 /** 839 * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device 840 * @dev: LPSS device 841 * @pdata: pointer to the private data of the LPSS device 842 * 843 * Restores the registers that were previously stored with acpi_lpss_save_ctx(). 844 */ 845 static void acpi_lpss_restore_ctx(struct device *dev, 846 struct lpss_private_data *pdata) 847 { 848 unsigned int i; 849 850 for (i = 0; i < LPSS_PRV_REG_COUNT; i++) { 851 unsigned long offset = i * sizeof(u32); 852 853 __lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset); 854 dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n", 855 pdata->prv_reg_ctx[i], offset); 856 } 857 } 858 859 static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata) 860 { 861 /* 862 * The following delay is needed or the subsequent write operations may 863 * fail. The LPSS devices are actually PCI devices and the PCI spec 864 * expects 10ms delay before the device can be accessed after D3 to D0 865 * transition. However some platforms like BSW does not need this delay. 866 */ 867 unsigned int delay = 10; /* default 10ms delay */ 868 869 if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY) 870 delay = 0; 871 872 msleep(delay); 873 } 874 875 static int acpi_lpss_activate(struct device *dev) 876 { 877 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 878 int ret; 879 880 ret = acpi_dev_resume(dev); 881 if (ret) 882 return ret; 883 884 acpi_lpss_d3_to_d0_delay(pdata); 885 886 /* 887 * This is called only on ->probe() stage where a device is either in 888 * known state defined by BIOS or most likely powered off. Due to this 889 * we have to deassert reset line to be sure that ->probe() will 890 * recognize the device. 891 */ 892 if (pdata->dev_desc->flags & LPSS_SAVE_CTX) 893 lpss_deassert_reset(pdata); 894 895 return 0; 896 } 897 898 static void acpi_lpss_dismiss(struct device *dev) 899 { 900 acpi_dev_suspend(dev, false); 901 } 902 903 /* IOSF SB for LPSS island */ 904 #define LPSS_IOSF_UNIT_LPIOEP 0xA0 905 #define LPSS_IOSF_UNIT_LPIO1 0xAB 906 #define LPSS_IOSF_UNIT_LPIO2 0xAC 907 908 #define LPSS_IOSF_PMCSR 0x84 909 #define LPSS_PMCSR_D0 0 910 #define LPSS_PMCSR_D3hot 3 911 #define LPSS_PMCSR_Dx_MASK GENMASK(1, 0) 912 913 #define LPSS_IOSF_GPIODEF0 0x154 914 #define LPSS_GPIODEF0_DMA1_D3 BIT(2) 915 #define LPSS_GPIODEF0_DMA2_D3 BIT(3) 916 #define LPSS_GPIODEF0_DMA_D3_MASK GENMASK(3, 2) 917 #define LPSS_GPIODEF0_DMA_LLP BIT(13) 918 919 static DEFINE_MUTEX(lpss_iosf_mutex); 920 static bool lpss_iosf_d3_entered = true; 921 922 static void lpss_iosf_enter_d3_state(void) 923 { 924 u32 value1 = 0; 925 u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP; 926 u32 value2 = LPSS_PMCSR_D3hot; 927 u32 mask2 = LPSS_PMCSR_Dx_MASK; 928 /* 929 * PMC provides an information about actual status of the LPSS devices. 930 * Here we read the values related to LPSS power island, i.e. LPSS 931 * devices, excluding both LPSS DMA controllers, along with SCC domain. 932 */ 933 u32 func_dis, d3_sts_0, pmc_status; 934 int ret; 935 936 ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis); 937 if (ret) 938 return; 939 940 mutex_lock(&lpss_iosf_mutex); 941 942 ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0); 943 if (ret) 944 goto exit; 945 946 /* 947 * Get the status of entire LPSS power island per device basis. 948 * Shutdown both LPSS DMA controllers if and only if all other devices 949 * are already in D3hot. 950 */ 951 pmc_status = (~(d3_sts_0 | func_dis)) & pmc_atom_d3_mask; 952 if (pmc_status) 953 goto exit; 954 955 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE, 956 LPSS_IOSF_PMCSR, value2, mask2); 957 958 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE, 959 LPSS_IOSF_PMCSR, value2, mask2); 960 961 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE, 962 LPSS_IOSF_GPIODEF0, value1, mask1); 963 964 lpss_iosf_d3_entered = true; 965 966 exit: 967 mutex_unlock(&lpss_iosf_mutex); 968 } 969 970 static void lpss_iosf_exit_d3_state(void) 971 { 972 u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 | 973 LPSS_GPIODEF0_DMA_LLP; 974 u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP; 975 u32 value2 = LPSS_PMCSR_D0; 976 u32 mask2 = LPSS_PMCSR_Dx_MASK; 977 978 mutex_lock(&lpss_iosf_mutex); 979 980 if (!lpss_iosf_d3_entered) 981 goto exit; 982 983 lpss_iosf_d3_entered = false; 984 985 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE, 986 LPSS_IOSF_GPIODEF0, value1, mask1); 987 988 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE, 989 LPSS_IOSF_PMCSR, value2, mask2); 990 991 iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE, 992 LPSS_IOSF_PMCSR, value2, mask2); 993 994 exit: 995 mutex_unlock(&lpss_iosf_mutex); 996 } 997 998 static int acpi_lpss_suspend(struct device *dev, bool wakeup) 999 { 1000 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 1001 int ret; 1002 1003 if (pdata->dev_desc->flags & LPSS_SAVE_CTX) 1004 acpi_lpss_save_ctx(dev, pdata); 1005 1006 ret = acpi_dev_suspend(dev, wakeup); 1007 1008 /* 1009 * This call must be last in the sequence, otherwise PMC will return 1010 * wrong status for devices being about to be powered off. See 1011 * lpss_iosf_enter_d3_state() for further information. 1012 */ 1013 if (acpi_target_system_state() == ACPI_STATE_S0 && 1014 lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available()) 1015 lpss_iosf_enter_d3_state(); 1016 1017 return ret; 1018 } 1019 1020 static int acpi_lpss_resume(struct device *dev) 1021 { 1022 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 1023 int ret; 1024 1025 /* 1026 * This call is kept first to be in symmetry with 1027 * acpi_lpss_runtime_suspend() one. 1028 */ 1029 if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available()) 1030 lpss_iosf_exit_d3_state(); 1031 1032 ret = acpi_dev_resume(dev); 1033 if (ret) 1034 return ret; 1035 1036 acpi_lpss_d3_to_d0_delay(pdata); 1037 1038 if (pdata->dev_desc->flags & LPSS_SAVE_CTX) 1039 acpi_lpss_restore_ctx(dev, pdata); 1040 1041 return 0; 1042 } 1043 1044 #ifdef CONFIG_PM_SLEEP 1045 static int acpi_lpss_do_suspend_late(struct device *dev) 1046 { 1047 int ret; 1048 1049 if (dev_pm_smart_suspend_and_suspended(dev)) 1050 return 0; 1051 1052 ret = pm_generic_suspend_late(dev); 1053 return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev)); 1054 } 1055 1056 static int acpi_lpss_suspend_late(struct device *dev) 1057 { 1058 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 1059 1060 if (pdata->dev_desc->resume_from_noirq) 1061 return 0; 1062 1063 return acpi_lpss_do_suspend_late(dev); 1064 } 1065 1066 static int acpi_lpss_suspend_noirq(struct device *dev) 1067 { 1068 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 1069 int ret; 1070 1071 if (pdata->dev_desc->resume_from_noirq) { 1072 ret = acpi_lpss_do_suspend_late(dev); 1073 if (ret) 1074 return ret; 1075 } 1076 1077 return acpi_subsys_suspend_noirq(dev); 1078 } 1079 1080 static int acpi_lpss_do_resume_early(struct device *dev) 1081 { 1082 int ret = acpi_lpss_resume(dev); 1083 1084 return ret ? ret : pm_generic_resume_early(dev); 1085 } 1086 1087 static int acpi_lpss_resume_early(struct device *dev) 1088 { 1089 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 1090 1091 if (pdata->dev_desc->resume_from_noirq) 1092 return 0; 1093 1094 return acpi_lpss_do_resume_early(dev); 1095 } 1096 1097 static int acpi_lpss_resume_noirq(struct device *dev) 1098 { 1099 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 1100 int ret; 1101 1102 ret = acpi_subsys_resume_noirq(dev); 1103 if (ret) 1104 return ret; 1105 1106 if (!dev_pm_may_skip_resume(dev) && pdata->dev_desc->resume_from_noirq) 1107 ret = acpi_lpss_do_resume_early(dev); 1108 1109 return ret; 1110 } 1111 1112 #endif /* CONFIG_PM_SLEEP */ 1113 1114 static int acpi_lpss_runtime_suspend(struct device *dev) 1115 { 1116 int ret = pm_generic_runtime_suspend(dev); 1117 1118 return ret ? ret : acpi_lpss_suspend(dev, true); 1119 } 1120 1121 static int acpi_lpss_runtime_resume(struct device *dev) 1122 { 1123 int ret = acpi_lpss_resume(dev); 1124 1125 return ret ? ret : pm_generic_runtime_resume(dev); 1126 } 1127 #endif /* CONFIG_PM */ 1128 1129 static struct dev_pm_domain acpi_lpss_pm_domain = { 1130 #ifdef CONFIG_PM 1131 .activate = acpi_lpss_activate, 1132 .dismiss = acpi_lpss_dismiss, 1133 #endif 1134 .ops = { 1135 #ifdef CONFIG_PM 1136 #ifdef CONFIG_PM_SLEEP 1137 .prepare = acpi_subsys_prepare, 1138 .complete = acpi_subsys_complete, 1139 .suspend = acpi_subsys_suspend, 1140 .suspend_late = acpi_lpss_suspend_late, 1141 .suspend_noirq = acpi_lpss_suspend_noirq, 1142 .resume_noirq = acpi_lpss_resume_noirq, 1143 .resume_early = acpi_lpss_resume_early, 1144 .freeze = acpi_subsys_freeze, 1145 .freeze_late = acpi_subsys_freeze_late, 1146 .freeze_noirq = acpi_subsys_freeze_noirq, 1147 .thaw_noirq = acpi_subsys_thaw_noirq, 1148 .poweroff = acpi_subsys_suspend, 1149 .poweroff_late = acpi_lpss_suspend_late, 1150 .poweroff_noirq = acpi_subsys_suspend_noirq, 1151 .restore_noirq = acpi_subsys_resume_noirq, 1152 .restore_early = acpi_lpss_resume_early, 1153 #endif 1154 .runtime_suspend = acpi_lpss_runtime_suspend, 1155 .runtime_resume = acpi_lpss_runtime_resume, 1156 #endif 1157 }, 1158 }; 1159 1160 static int acpi_lpss_platform_notify(struct notifier_block *nb, 1161 unsigned long action, void *data) 1162 { 1163 struct platform_device *pdev = to_platform_device(data); 1164 struct lpss_private_data *pdata; 1165 struct acpi_device *adev; 1166 const struct acpi_device_id *id; 1167 1168 id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev); 1169 if (!id || !id->driver_data) 1170 return 0; 1171 1172 if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev)) 1173 return 0; 1174 1175 pdata = acpi_driver_data(adev); 1176 if (!pdata) 1177 return 0; 1178 1179 if (pdata->mmio_base && 1180 pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) { 1181 dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n"); 1182 return 0; 1183 } 1184 1185 switch (action) { 1186 case BUS_NOTIFY_BIND_DRIVER: 1187 dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain); 1188 break; 1189 case BUS_NOTIFY_DRIVER_NOT_BOUND: 1190 case BUS_NOTIFY_UNBOUND_DRIVER: 1191 dev_pm_domain_set(&pdev->dev, NULL); 1192 break; 1193 case BUS_NOTIFY_ADD_DEVICE: 1194 dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain); 1195 if (pdata->dev_desc->flags & LPSS_LTR) 1196 return sysfs_create_group(&pdev->dev.kobj, 1197 &lpss_attr_group); 1198 break; 1199 case BUS_NOTIFY_DEL_DEVICE: 1200 if (pdata->dev_desc->flags & LPSS_LTR) 1201 sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group); 1202 dev_pm_domain_set(&pdev->dev, NULL); 1203 break; 1204 default: 1205 break; 1206 } 1207 1208 return 0; 1209 } 1210 1211 static struct notifier_block acpi_lpss_nb = { 1212 .notifier_call = acpi_lpss_platform_notify, 1213 }; 1214 1215 static void acpi_lpss_bind(struct device *dev) 1216 { 1217 struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev)); 1218 1219 if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR)) 1220 return; 1221 1222 if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) 1223 dev->power.set_latency_tolerance = acpi_lpss_set_ltr; 1224 else 1225 dev_err(dev, "MMIO size insufficient to access LTR\n"); 1226 } 1227 1228 static void acpi_lpss_unbind(struct device *dev) 1229 { 1230 dev->power.set_latency_tolerance = NULL; 1231 } 1232 1233 static struct acpi_scan_handler lpss_handler = { 1234 .ids = acpi_lpss_device_ids, 1235 .attach = acpi_lpss_create_device, 1236 .bind = acpi_lpss_bind, 1237 .unbind = acpi_lpss_unbind, 1238 }; 1239 1240 void __init acpi_lpss_init(void) 1241 { 1242 const struct x86_cpu_id *id; 1243 int ret; 1244 1245 ret = lpt_clk_init(); 1246 if (ret) 1247 return; 1248 1249 id = x86_match_cpu(lpss_cpu_ids); 1250 if (id) 1251 lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON; 1252 1253 bus_register_notifier(&platform_bus_type, &acpi_lpss_nb); 1254 acpi_scan_add_handler(&lpss_handler); 1255 } 1256 1257 #else 1258 1259 static struct acpi_scan_handler lpss_handler = { 1260 .ids = acpi_lpss_device_ids, 1261 }; 1262 1263 void __init acpi_lpss_init(void) 1264 { 1265 acpi_scan_add_handler(&lpss_handler); 1266 } 1267 1268 #endif /* CONFIG_X86_INTEL_LPSS */ 1269