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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * ACPI support for Intel Lynxpoint LPSS.
   4 *
   5 * Copyright (C) 2013, Intel Corporation
   6 * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
   7 *          Rafael J. Wysocki <rafael.j.wysocki@intel.com>
   8 */
   9
  10#include <linux/acpi.h>
  11#include <linux/clkdev.h>
  12#include <linux/clk-provider.h>
  13#include <linux/dmi.h>
  14#include <linux/err.h>
  15#include <linux/io.h>
  16#include <linux/mutex.h>
  17#include <linux/pci.h>
  18#include <linux/platform_device.h>
  19#include <linux/platform_data/x86/clk-lpss.h>
  20#include <linux/platform_data/x86/pmc_atom.h>
  21#include <linux/pm_domain.h>
  22#include <linux/pm_runtime.h>
  23#include <linux/pwm.h>
  24#include <linux/pxa2xx_ssp.h>
  25#include <linux/suspend.h>
  26#include <linux/delay.h>
  27
  28#include "internal.h"
  29
  30#ifdef CONFIG_X86_INTEL_LPSS
  31
  32#include <asm/cpu_device_id.h>
  33#include <asm/intel-family.h>
  34#include <asm/iosf_mbi.h>
  35
  36#define LPSS_ADDR(desc) ((unsigned long)&desc)
  37
  38#define LPSS_CLK_SIZE	0x04
  39#define LPSS_LTR_SIZE	0x18
  40
  41/* Offsets relative to LPSS_PRIVATE_OFFSET */
  42#define LPSS_CLK_DIVIDER_DEF_MASK	(BIT(1) | BIT(16))
  43#define LPSS_RESETS			0x04
  44#define LPSS_RESETS_RESET_FUNC		BIT(0)
  45#define LPSS_RESETS_RESET_APB		BIT(1)
  46#define LPSS_GENERAL			0x08
  47#define LPSS_GENERAL_LTR_MODE_SW	BIT(2)
  48#define LPSS_GENERAL_UART_RTS_OVRD	BIT(3)
  49#define LPSS_SW_LTR			0x10
  50#define LPSS_AUTO_LTR			0x14
  51#define LPSS_LTR_SNOOP_REQ		BIT(15)
  52#define LPSS_LTR_SNOOP_MASK		0x0000FFFF
  53#define LPSS_LTR_SNOOP_LAT_1US		0x800
  54#define LPSS_LTR_SNOOP_LAT_32US		0xC00
  55#define LPSS_LTR_SNOOP_LAT_SHIFT	5
  56#define LPSS_LTR_SNOOP_LAT_CUTOFF	3000
  57#define LPSS_LTR_MAX_VAL		0x3FF
  58#define LPSS_TX_INT			0x20
  59#define LPSS_TX_INT_MASK		BIT(1)
  60
  61#define LPSS_PRV_REG_COUNT		9
  62
  63/* LPSS Flags */
  64#define LPSS_CLK			BIT(0)
  65#define LPSS_CLK_GATE			BIT(1)
  66#define LPSS_CLK_DIVIDER		BIT(2)
  67#define LPSS_LTR			BIT(3)
  68#define LPSS_SAVE_CTX			BIT(4)
  69/*
  70 * For some devices the DSDT AML code for another device turns off the device
  71 * before our suspend handler runs, causing us to read/save all 1-s (0xffffffff)
  72 * as ctx register values.
  73 * Luckily these devices always use the same ctx register values, so we can
  74 * work around this by saving the ctx registers once on activation.
  75 */
  76#define LPSS_SAVE_CTX_ONCE		BIT(5)
  77#define LPSS_NO_D3_DELAY		BIT(6)
  78
  79struct lpss_private_data;
  80
  81struct lpss_device_desc {
  82	unsigned int flags;
  83	const char *clk_con_id;
  84	unsigned int prv_offset;
  85	size_t prv_size_override;
  86	const struct property_entry *properties;
  87	void (*setup)(struct lpss_private_data *pdata);
  88	bool resume_from_noirq;
  89};
  90
  91static const struct lpss_device_desc lpss_dma_desc = {
  92	.flags = LPSS_CLK,
  93};
  94
  95struct lpss_private_data {
  96	struct acpi_device *adev;
  97	void __iomem *mmio_base;
  98	resource_size_t mmio_size;
  99	unsigned int fixed_clk_rate;
 100	struct clk *clk;
 101	const struct lpss_device_desc *dev_desc;
 102	u32 prv_reg_ctx[LPSS_PRV_REG_COUNT];
 103};
 104
 105/* Devices which need to be in D3 before lpss_iosf_enter_d3_state() proceeds */
 106static u32 pmc_atom_d3_mask = 0xfe000ffe;
 107
 108/* LPSS run time quirks */
 109static unsigned int lpss_quirks;
 110
 111/*
 112 * LPSS_QUIRK_ALWAYS_POWER_ON: override power state for LPSS DMA device.
 113 *
 114 * The LPSS DMA controller has neither _PS0 nor _PS3 method. Moreover
 115 * it can be powered off automatically whenever the last LPSS device goes down.
 116 * In case of no power any access to the DMA controller will hang the system.
 117 * The behaviour is reproduced on some HP laptops based on Intel BayTrail as
 118 * well as on ASuS T100TA transformer.
 119 *
 120 * This quirk overrides power state of entire LPSS island to keep DMA powered
 121 * on whenever we have at least one other device in use.
 122 */
 123#define LPSS_QUIRK_ALWAYS_POWER_ON	BIT(0)
 124
 125/* UART Component Parameter Register */
 126#define LPSS_UART_CPR			0xF4
 127#define LPSS_UART_CPR_AFCE		BIT(4)
 128
 129static void lpss_uart_setup(struct lpss_private_data *pdata)
 130{
 131	unsigned int offset;
 132	u32 val;
 133
 134	offset = pdata->dev_desc->prv_offset + LPSS_TX_INT;
 135	val = readl(pdata->mmio_base + offset);
 136	writel(val | LPSS_TX_INT_MASK, pdata->mmio_base + offset);
 137
 138	val = readl(pdata->mmio_base + LPSS_UART_CPR);
 139	if (!(val & LPSS_UART_CPR_AFCE)) {
 140		offset = pdata->dev_desc->prv_offset + LPSS_GENERAL;
 141		val = readl(pdata->mmio_base + offset);
 142		val |= LPSS_GENERAL_UART_RTS_OVRD;
 143		writel(val, pdata->mmio_base + offset);
 144	}
 145}
 146
 147static void lpss_deassert_reset(struct lpss_private_data *pdata)
 148{
 149	unsigned int offset;
 150	u32 val;
 151
 152	offset = pdata->dev_desc->prv_offset + LPSS_RESETS;
 153	val = readl(pdata->mmio_base + offset);
 154	val |= LPSS_RESETS_RESET_APB | LPSS_RESETS_RESET_FUNC;
 155	writel(val, pdata->mmio_base + offset);
 156}
 157
 158/*
 159 * BYT PWM used for backlight control by the i915 driver on systems without
 160 * the Crystal Cove PMIC.
 161 */
 162static struct pwm_lookup byt_pwm_lookup[] = {
 163	PWM_LOOKUP_WITH_MODULE("80860F09:00", 0, "0000:00:02.0",
 164			       "pwm_soc_backlight", 0, PWM_POLARITY_NORMAL,
 165			       "pwm-lpss-platform"),
 166};
 167
 168static void byt_pwm_setup(struct lpss_private_data *pdata)
 169{
 170	u64 uid;
 171
 172	/* Only call pwm_add_table for the first PWM controller */
 173	if (acpi_dev_uid_to_integer(pdata->adev, &uid) || uid != 1)
 174		return;
 175
 176	pwm_add_table(byt_pwm_lookup, ARRAY_SIZE(byt_pwm_lookup));
 177}
 178
 179#define LPSS_I2C_ENABLE			0x6c
 180
 181static void byt_i2c_setup(struct lpss_private_data *pdata)
 182{
 183	acpi_handle handle = pdata->adev->handle;
 184	unsigned long long shared_host = 0;
 185	acpi_status status;
 186	u64 uid;
 187
 188	/* Expected to always be successfull, but better safe then sorry */
 189	if (!acpi_dev_uid_to_integer(pdata->adev, &uid) && uid) {
 190		/* Detect I2C bus shared with PUNIT and ignore its d3 status */
 191		status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host);
 192		if (ACPI_SUCCESS(status) && shared_host)
 193			pmc_atom_d3_mask &= ~(BIT_LPSS2_F1_I2C1 << (uid - 1));
 194	}
 195
 196	lpss_deassert_reset(pdata);
 197
 198	if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset))
 199		pdata->fixed_clk_rate = 133000000;
 200
 201	writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
 202}
 203
 204/* BSW PWM used for backlight control by the i915 driver */
 205static struct pwm_lookup bsw_pwm_lookup[] = {
 206	PWM_LOOKUP_WITH_MODULE("80862288:00", 0, "0000:00:02.0",
 207			       "pwm_soc_backlight", 0, PWM_POLARITY_NORMAL,
 208			       "pwm-lpss-platform"),
 209};
 210
 211static void bsw_pwm_setup(struct lpss_private_data *pdata)
 212{
 213	u64 uid;
 214
 215	/* Only call pwm_add_table for the first PWM controller */
 216	if (acpi_dev_uid_to_integer(pdata->adev, &uid) || uid != 1)
 217		return;
 218
 219	pwm_add_table(bsw_pwm_lookup, ARRAY_SIZE(bsw_pwm_lookup));
 220}
 221
 222static const struct property_entry lpt_spi_properties[] = {
 223	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_LPT_SSP),
 224	{ }
 225};
 226
 227static const struct lpss_device_desc lpt_spi_dev_desc = {
 228	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR
 229			| LPSS_SAVE_CTX,
 230	.prv_offset = 0x800,
 231	.properties = lpt_spi_properties,
 232};
 233
 234static const struct lpss_device_desc lpt_i2c_dev_desc = {
 235	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR | LPSS_SAVE_CTX,
 236	.prv_offset = 0x800,
 237};
 238
 239static struct property_entry uart_properties[] = {
 240	PROPERTY_ENTRY_U32("reg-io-width", 4),
 241	PROPERTY_ENTRY_U32("reg-shift", 2),
 242	PROPERTY_ENTRY_BOOL("snps,uart-16550-compatible"),
 243	{ },
 244};
 245
 246static const struct lpss_device_desc lpt_uart_dev_desc = {
 247	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR
 248			| LPSS_SAVE_CTX,
 249	.clk_con_id = "baudclk",
 250	.prv_offset = 0x800,
 251	.setup = lpss_uart_setup,
 252	.properties = uart_properties,
 253};
 254
 255static const struct lpss_device_desc lpt_sdio_dev_desc = {
 256	.flags = LPSS_LTR,
 257	.prv_offset = 0x1000,
 258	.prv_size_override = 0x1018,
 259};
 260
 261static const struct lpss_device_desc byt_pwm_dev_desc = {
 262	.flags = LPSS_SAVE_CTX,
 263	.prv_offset = 0x800,
 264	.setup = byt_pwm_setup,
 265};
 266
 267static const struct lpss_device_desc bsw_pwm_dev_desc = {
 268	.flags = LPSS_SAVE_CTX_ONCE | LPSS_NO_D3_DELAY,
 269	.prv_offset = 0x800,
 270	.setup = bsw_pwm_setup,
 271	.resume_from_noirq = true,
 272};
 273
 274static const struct lpss_device_desc byt_uart_dev_desc = {
 275	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
 276	.clk_con_id = "baudclk",
 277	.prv_offset = 0x800,
 278	.setup = lpss_uart_setup,
 279	.properties = uart_properties,
 280};
 281
 282static const struct lpss_device_desc bsw_uart_dev_desc = {
 283	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
 284			| LPSS_NO_D3_DELAY,
 285	.clk_con_id = "baudclk",
 286	.prv_offset = 0x800,
 287	.setup = lpss_uart_setup,
 288	.properties = uart_properties,
 289};
 290
 291static const struct property_entry byt_spi_properties[] = {
 292	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_BYT_SSP),
 293	{ }
 294};
 295
 296static const struct lpss_device_desc byt_spi_dev_desc = {
 297	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
 298	.prv_offset = 0x400,
 299	.properties = byt_spi_properties,
 300};
 301
 302static const struct lpss_device_desc byt_sdio_dev_desc = {
 303	.flags = LPSS_CLK,
 304};
 305
 306static const struct lpss_device_desc byt_i2c_dev_desc = {
 307	.flags = LPSS_CLK | LPSS_SAVE_CTX,
 308	.prv_offset = 0x800,
 309	.setup = byt_i2c_setup,
 310	.resume_from_noirq = true,
 311};
 312
 313static const struct lpss_device_desc bsw_i2c_dev_desc = {
 314	.flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
 315	.prv_offset = 0x800,
 316	.setup = byt_i2c_setup,
 317	.resume_from_noirq = true,
 318};
 319
 320static const struct property_entry bsw_spi_properties[] = {
 321	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_BSW_SSP),
 322	{ }
 323};
 324
 325static const struct lpss_device_desc bsw_spi_dev_desc = {
 326	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
 327			| LPSS_NO_D3_DELAY,
 328	.prv_offset = 0x400,
 329	.setup = lpss_deassert_reset,
 330	.properties = bsw_spi_properties,
 331};
 332
 333static const struct x86_cpu_id lpss_cpu_ids[] = {
 334	X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT,	NULL),
 335	X86_MATCH_INTEL_FAM6_MODEL(ATOM_AIRMONT,	NULL),
 336	{}
 337};
 338
 339#else
 340
 341#define LPSS_ADDR(desc) (0UL)
 342
 343#endif /* CONFIG_X86_INTEL_LPSS */
 344
 345static const struct acpi_device_id acpi_lpss_device_ids[] = {
 346	/* Generic LPSS devices */
 347	{ "INTL9C60", LPSS_ADDR(lpss_dma_desc) },
 348
 349	/* Lynxpoint LPSS devices */
 350	{ "INT33C0", LPSS_ADDR(lpt_spi_dev_desc) },
 351	{ "INT33C1", LPSS_ADDR(lpt_spi_dev_desc) },
 352	{ "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },
 353	{ "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },
 354	{ "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },
 355	{ "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },
 356	{ "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },
 357	{ "INT33C7", },
 358
 359	/* BayTrail LPSS devices */
 360	{ "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },
 361	{ "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },
 362	{ "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },
 363	{ "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },
 364	{ "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },
 365	{ "INT33B2", },
 366	{ "INT33FC", },
 367
 368	/* Braswell LPSS devices */
 369	{ "80862286", LPSS_ADDR(lpss_dma_desc) },
 370	{ "80862288", LPSS_ADDR(bsw_pwm_dev_desc) },
 371	{ "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },
 372	{ "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },
 373	{ "808622C0", LPSS_ADDR(lpss_dma_desc) },
 374	{ "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) },
 375
 376	/* Broadwell LPSS devices */
 377	{ "INT3430", LPSS_ADDR(lpt_spi_dev_desc) },
 378	{ "INT3431", LPSS_ADDR(lpt_spi_dev_desc) },
 379	{ "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },
 380	{ "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },
 381	{ "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },
 382	{ "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },
 383	{ "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },
 384	{ "INT3437", },
 385
 386	/* Wildcat Point LPSS devices */
 387	{ "INT3438", LPSS_ADDR(lpt_spi_dev_desc) },
 388
 389	{ }
 390};
 391
 392#ifdef CONFIG_X86_INTEL_LPSS
 393
 394/* LPSS main clock device. */
 395static struct platform_device *lpss_clk_dev;
 396
 397static inline void lpt_register_clock_device(void)
 398{
 399	lpss_clk_dev = platform_device_register_simple("clk-lpss-atom",
 400						       PLATFORM_DEVID_NONE,
 401						       NULL, 0);
 402}
 403
 404static int register_device_clock(struct acpi_device *adev,
 405				 struct lpss_private_data *pdata)
 406{
 407	const struct lpss_device_desc *dev_desc = pdata->dev_desc;
 408	const char *devname = dev_name(&adev->dev);
 409	struct clk *clk;
 410	struct lpss_clk_data *clk_data;
 411	const char *parent, *clk_name;
 412	void __iomem *prv_base;
 413
 414	if (!lpss_clk_dev)
 415		lpt_register_clock_device();
 416
 417	if (IS_ERR(lpss_clk_dev))
 418		return PTR_ERR(lpss_clk_dev);
 419
 420	clk_data = platform_get_drvdata(lpss_clk_dev);
 421	if (!clk_data)
 422		return -ENODEV;
 423	clk = clk_data->clk;
 424
 425	if (!pdata->mmio_base
 426	    || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
 427		return -ENODATA;
 428
 429	parent = clk_data->name;
 430	prv_base = pdata->mmio_base + dev_desc->prv_offset;
 431
 432	if (pdata->fixed_clk_rate) {
 433		clk = clk_register_fixed_rate(NULL, devname, parent, 0,
 434					      pdata->fixed_clk_rate);
 435		goto out;
 436	}
 437
 438	if (dev_desc->flags & LPSS_CLK_GATE) {
 439		clk = clk_register_gate(NULL, devname, parent, 0,
 440					prv_base, 0, 0, NULL);
 441		parent = devname;
 442	}
 443
 444	if (dev_desc->flags & LPSS_CLK_DIVIDER) {
 445		/* Prevent division by zero */
 446		if (!readl(prv_base))
 447			writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
 448
 449		clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
 450		if (!clk_name)
 451			return -ENOMEM;
 452		clk = clk_register_fractional_divider(NULL, clk_name, parent,
 453						      CLK_FRAC_DIVIDER_POWER_OF_TWO_PS,
 454						      prv_base, 1, 15, 16, 15, 0, NULL);
 455		parent = clk_name;
 456
 457		clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
 458		if (!clk_name) {
 459			kfree(parent);
 460			return -ENOMEM;
 461		}
 462		clk = clk_register_gate(NULL, clk_name, parent,
 463					CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
 464					prv_base, 31, 0, NULL);
 465		kfree(parent);
 466		kfree(clk_name);
 467	}
 468out:
 469	if (IS_ERR(clk))
 470		return PTR_ERR(clk);
 471
 472	pdata->clk = clk;
 473	clk_register_clkdev(clk, dev_desc->clk_con_id, devname);
 474	return 0;
 475}
 476
 477struct lpss_device_links {
 478	const char *supplier_hid;
 479	const char *supplier_uid;
 480	const char *consumer_hid;
 481	const char *consumer_uid;
 482	u32 flags;
 483	const struct dmi_system_id *dep_missing_ids;
 484};
 485
 486/* Please keep this list sorted alphabetically by vendor and model */
 487static const struct dmi_system_id i2c1_dep_missing_dmi_ids[] = {
 488	{
 489		.matches = {
 490			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
 491			DMI_MATCH(DMI_PRODUCT_NAME, "T200TA"),
 492		},
 493	},
 494	{}
 495};
 496
 497/*
 498 * The _DEP method is used to identify dependencies but instead of creating
 499 * device links for every handle in _DEP, only links in the following list are
 500 * created. That is necessary because, in the general case, _DEP can refer to
 501 * devices that might not have drivers, or that are on different buses, or where
 502 * the supplier is not enumerated until after the consumer is probed.
 503 */
 504static const struct lpss_device_links lpss_device_links[] = {
 505	/* CHT External sdcard slot controller depends on PMIC I2C ctrl */
 506	{"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME},
 507	/* CHT iGPU depends on PMIC I2C controller */
 508	{"808622C1", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
 509	/* BYT iGPU depends on the Embedded Controller I2C controller (UID 1) */
 510	{"80860F41", "1", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME,
 511	 i2c1_dep_missing_dmi_ids},
 512	/* BYT CR iGPU depends on PMIC I2C controller (UID 5 on CR) */
 513	{"80860F41", "5", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
 514	/* BYT iGPU depends on PMIC I2C controller (UID 7 on non CR) */
 515	{"80860F41", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
 516};
 517
 518static bool acpi_lpss_is_supplier(struct acpi_device *adev,
 519				  const struct lpss_device_links *link)
 520{
 521	return acpi_dev_hid_uid_match(adev, link->supplier_hid, link->supplier_uid);
 522}
 523
 524static bool acpi_lpss_is_consumer(struct acpi_device *adev,
 525				  const struct lpss_device_links *link)
 526{
 527	return acpi_dev_hid_uid_match(adev, link->consumer_hid, link->consumer_uid);
 528}
 529
 530struct hid_uid {
 531	const char *hid;
 532	const char *uid;
 533};
 534
 535static int match_hid_uid(struct device *dev, const void *data)
 536{
 537	struct acpi_device *adev = ACPI_COMPANION(dev);
 538	const struct hid_uid *id = data;
 539
 540	if (!adev)
 541		return 0;
 542
 543	return acpi_dev_hid_uid_match(adev, id->hid, id->uid);
 544}
 545
 546static struct device *acpi_lpss_find_device(const char *hid, const char *uid)
 547{
 548	struct device *dev;
 549
 550	struct hid_uid data = {
 551		.hid = hid,
 552		.uid = uid,
 553	};
 554
 555	dev = bus_find_device(&platform_bus_type, NULL, &data, match_hid_uid);
 556	if (dev)
 557		return dev;
 558
 559	return bus_find_device(&pci_bus_type, NULL, &data, match_hid_uid);
 560}
 561
 562static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle)
 563{
 564	struct acpi_handle_list dep_devices;
 565	acpi_status status;
 566	int i;
 567
 568	if (!acpi_has_method(adev->handle, "_DEP"))
 569		return false;
 570
 571	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
 572					 &dep_devices);
 573	if (ACPI_FAILURE(status)) {
 574		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
 575		return false;
 576	}
 577
 578	for (i = 0; i < dep_devices.count; i++) {
 579		if (dep_devices.handles[i] == handle)
 580			return true;
 581	}
 582
 583	return false;
 584}
 585
 586static void acpi_lpss_link_consumer(struct device *dev1,
 587				    const struct lpss_device_links *link)
 588{
 589	struct device *dev2;
 590
 591	dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid);
 592	if (!dev2)
 593		return;
 594
 595	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
 596	    || acpi_lpss_dep(ACPI_COMPANION(dev2), ACPI_HANDLE(dev1)))
 597		device_link_add(dev2, dev1, link->flags);
 598
 599	put_device(dev2);
 600}
 601
 602static void acpi_lpss_link_supplier(struct device *dev1,
 603				    const struct lpss_device_links *link)
 604{
 605	struct device *dev2;
 606
 607	dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid);
 608	if (!dev2)
 609		return;
 610
 611	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
 612	    || acpi_lpss_dep(ACPI_COMPANION(dev1), ACPI_HANDLE(dev2)))
 613		device_link_add(dev1, dev2, link->flags);
 614
 615	put_device(dev2);
 616}
 617
 618static void acpi_lpss_create_device_links(struct acpi_device *adev,
 619					  struct platform_device *pdev)
 620{
 621	int i;
 622
 623	for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) {
 624		const struct lpss_device_links *link = &lpss_device_links[i];
 625
 626		if (acpi_lpss_is_supplier(adev, link))
 627			acpi_lpss_link_consumer(&pdev->dev, link);
 628
 629		if (acpi_lpss_is_consumer(adev, link))
 630			acpi_lpss_link_supplier(&pdev->dev, link);
 631	}
 632}
 633
 634static int acpi_lpss_create_device(struct acpi_device *adev,
 635				   const struct acpi_device_id *id)
 636{
 637	const struct lpss_device_desc *dev_desc;
 638	struct lpss_private_data *pdata;
 639	struct resource_entry *rentry;
 640	struct list_head resource_list;
 641	struct platform_device *pdev;
 642	int ret;
 643
 644	dev_desc = (const struct lpss_device_desc *)id->driver_data;
 645	if (!dev_desc) {
 646		pdev = acpi_create_platform_device(adev, NULL);
 647		return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
 648	}
 649	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
 650	if (!pdata)
 651		return -ENOMEM;
 652
 653	INIT_LIST_HEAD(&resource_list);
 654	ret = acpi_dev_get_memory_resources(adev, &resource_list);
 655	if (ret < 0)
 656		goto err_out;
 657
 658	rentry = list_first_entry_or_null(&resource_list, struct resource_entry, node);
 659	if (rentry) {
 660		if (dev_desc->prv_size_override)
 661			pdata->mmio_size = dev_desc->prv_size_override;
 662		else
 663			pdata->mmio_size = resource_size(rentry->res);
 664		pdata->mmio_base = ioremap(rentry->res->start, pdata->mmio_size);
 665	}
 666
 667	acpi_dev_free_resource_list(&resource_list);
 668
 669	if (!pdata->mmio_base) {
 670		/* Avoid acpi_bus_attach() instantiating a pdev for this dev. */
 671		adev->pnp.type.platform_id = 0;
 672		goto out_free;
 673	}
 674
 675	pdata->adev = adev;
 676	pdata->dev_desc = dev_desc;
 677
 678	if (dev_desc->setup)
 679		dev_desc->setup(pdata);
 680
 681	if (dev_desc->flags & LPSS_CLK) {
 682		ret = register_device_clock(adev, pdata);
 683		if (ret)
 684			goto out_free;
 685	}
 686
 687	/*
 688	 * This works around a known issue in ACPI tables where LPSS devices
 689	 * have _PS0 and _PS3 without _PSC (and no power resources), so
 690	 * acpi_bus_init_power() will assume that the BIOS has put them into D0.
 691	 */
 692	acpi_device_fix_up_power(adev);
 693
 694	adev->driver_data = pdata;
 695	pdev = acpi_create_platform_device(adev, dev_desc->properties);
 696	if (IS_ERR_OR_NULL(pdev)) {
 697		adev->driver_data = NULL;
 698		ret = PTR_ERR(pdev);
 699		goto err_out;
 700	}
 701
 702	acpi_lpss_create_device_links(adev, pdev);
 703	return 1;
 704
 705out_free:
 706	/* Skip the device, but continue the namespace scan */
 707	ret = 0;
 708err_out:
 709	kfree(pdata);
 710	return ret;
 711}
 712
 713static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
 714{
 715	return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
 716}
 717
 718static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
 719			     unsigned int reg)
 720{
 721	writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
 722}
 723
 724static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
 725{
 726	struct acpi_device *adev = ACPI_COMPANION(dev);
 727	struct lpss_private_data *pdata;
 728	unsigned long flags;
 729	int ret;
 730
 731	if (WARN_ON(!adev))
 732		return -ENODEV;
 733
 734	spin_lock_irqsave(&dev->power.lock, flags);
 735	if (pm_runtime_suspended(dev)) {
 736		ret = -EAGAIN;
 737		goto out;
 738	}
 739	pdata = acpi_driver_data(adev);
 740	if (WARN_ON(!pdata || !pdata->mmio_base)) {
 741		ret = -ENODEV;
 742		goto out;
 743	}
 744	*val = __lpss_reg_read(pdata, reg);
 745	ret = 0;
 746
 747 out:
 748	spin_unlock_irqrestore(&dev->power.lock, flags);
 749	return ret;
 750}
 751
 752static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
 753			     char *buf)
 754{
 755	u32 ltr_value = 0;
 756	unsigned int reg;
 757	int ret;
 758
 759	reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
 760	ret = lpss_reg_read(dev, reg, &ltr_value);
 761	if (ret)
 762		return ret;
 763
 764	return sysfs_emit(buf, "%08x\n", ltr_value);
 765}
 766
 767static ssize_t lpss_ltr_mode_show(struct device *dev,
 768				  struct device_attribute *attr, char *buf)
 769{
 770	u32 ltr_mode = 0;
 771	char *outstr;
 772	int ret;
 773
 774	ret = lpss_reg_read(dev, LPSS_GENERAL, &ltr_mode);
 775	if (ret)
 776		return ret;
 777
 778	outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
 779	return sprintf(buf, "%s\n", outstr);
 780}
 781
 782static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
 783static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
 784static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
 785
 786static struct attribute *lpss_attrs[] = {
 787	&dev_attr_auto_ltr.attr,
 788	&dev_attr_sw_ltr.attr,
 789	&dev_attr_ltr_mode.attr,
 790	NULL,
 791};
 792
 793static const struct attribute_group lpss_attr_group = {
 794	.attrs = lpss_attrs,
 795	.name = "lpss_ltr",
 796};
 797
 798static void acpi_lpss_set_ltr(struct device *dev, s32 val)
 799{
 800	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
 801	u32 ltr_mode, ltr_val;
 802
 803	ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
 804	if (val < 0) {
 805		if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
 806			ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
 807			__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
 808		}
 809		return;
 810	}
 811	ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
 812	if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
 813		ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
 814		val = LPSS_LTR_MAX_VAL;
 815	} else if (val > LPSS_LTR_MAX_VAL) {
 816		ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
 817		val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
 818	} else {
 819		ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
 820	}
 821	ltr_val |= val;
 822	__lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
 823	if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
 824		ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
 825		__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
 826	}
 827}
 828
 829#ifdef CONFIG_PM
 830/**
 831 * acpi_lpss_save_ctx() - Save the private registers of LPSS device
 832 * @dev: LPSS device
 833 * @pdata: pointer to the private data of the LPSS device
 834 *
 835 * Most LPSS devices have private registers which may loose their context when
 836 * the device is powered down. acpi_lpss_save_ctx() saves those registers into
 837 * prv_reg_ctx array.
 838 */
 839static void acpi_lpss_save_ctx(struct device *dev,
 840			       struct lpss_private_data *pdata)
 841{
 842	unsigned int i;
 843
 844	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
 845		unsigned long offset = i * sizeof(u32);
 846
 847		pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
 848		dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
 849			pdata->prv_reg_ctx[i], offset);
 850	}
 851}
 852
 853/**
 854 * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
 855 * @dev: LPSS device
 856 * @pdata: pointer to the private data of the LPSS device
 857 *
 858 * Restores the registers that were previously stored with acpi_lpss_save_ctx().
 859 */
 860static void acpi_lpss_restore_ctx(struct device *dev,
 861				  struct lpss_private_data *pdata)
 862{
 863	unsigned int i;
 864
 865	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
 866		unsigned long offset = i * sizeof(u32);
 867
 868		__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
 869		dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
 870			pdata->prv_reg_ctx[i], offset);
 871	}
 872}
 873
 874static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
 875{
 876	/*
 877	 * The following delay is needed or the subsequent write operations may
 878	 * fail. The LPSS devices are actually PCI devices and the PCI spec
 879	 * expects 10ms delay before the device can be accessed after D3 to D0
 880	 * transition. However some platforms like BSW does not need this delay.
 881	 */
 882	unsigned int delay = 10;	/* default 10ms delay */
 883
 884	if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)
 885		delay = 0;
 886
 887	msleep(delay);
 888}
 889
 890static int acpi_lpss_activate(struct device *dev)
 891{
 892	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
 893	int ret;
 894
 895	ret = acpi_dev_resume(dev);
 896	if (ret)
 897		return ret;
 898
 899	acpi_lpss_d3_to_d0_delay(pdata);
 900
 901	/*
 902	 * This is called only on ->probe() stage where a device is either in
 903	 * known state defined by BIOS or most likely powered off. Due to this
 904	 * we have to deassert reset line to be sure that ->probe() will
 905	 * recognize the device.
 906	 */
 907	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
 908		lpss_deassert_reset(pdata);
 909
 910#ifdef CONFIG_PM
 911	if (pdata->dev_desc->flags & LPSS_SAVE_CTX_ONCE)
 912		acpi_lpss_save_ctx(dev, pdata);
 913#endif
 914
 915	return 0;
 916}
 917
 918static void acpi_lpss_dismiss(struct device *dev)
 919{
 920	acpi_dev_suspend(dev, false);
 921}
 922
 923/* IOSF SB for LPSS island */
 924#define LPSS_IOSF_UNIT_LPIOEP		0xA0
 925#define LPSS_IOSF_UNIT_LPIO1		0xAB
 926#define LPSS_IOSF_UNIT_LPIO2		0xAC
 927
 928#define LPSS_IOSF_PMCSR			0x84
 929#define LPSS_PMCSR_D0			0
 930#define LPSS_PMCSR_D3hot		3
 931#define LPSS_PMCSR_Dx_MASK		GENMASK(1, 0)
 932
 933#define LPSS_IOSF_GPIODEF0		0x154
 934#define LPSS_GPIODEF0_DMA1_D3		BIT(2)
 935#define LPSS_GPIODEF0_DMA2_D3		BIT(3)
 936#define LPSS_GPIODEF0_DMA_D3_MASK	GENMASK(3, 2)
 937#define LPSS_GPIODEF0_DMA_LLP		BIT(13)
 938
 939static DEFINE_MUTEX(lpss_iosf_mutex);
 940static bool lpss_iosf_d3_entered = true;
 941
 942static void lpss_iosf_enter_d3_state(void)
 943{
 944	u32 value1 = 0;
 945	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
 946	u32 value2 = LPSS_PMCSR_D3hot;
 947	u32 mask2 = LPSS_PMCSR_Dx_MASK;
 948	/*
 949	 * PMC provides an information about actual status of the LPSS devices.
 950	 * Here we read the values related to LPSS power island, i.e. LPSS
 951	 * devices, excluding both LPSS DMA controllers, along with SCC domain.
 952	 */
 953	u32 func_dis, d3_sts_0, pmc_status;
 954	int ret;
 955
 956	ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);
 957	if (ret)
 958		return;
 959
 960	mutex_lock(&lpss_iosf_mutex);
 961
 962	ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);
 963	if (ret)
 964		goto exit;
 965
 966	/*
 967	 * Get the status of entire LPSS power island per device basis.
 968	 * Shutdown both LPSS DMA controllers if and only if all other devices
 969	 * are already in D3hot.
 970	 */
 971	pmc_status = (~(d3_sts_0 | func_dis)) & pmc_atom_d3_mask;
 972	if (pmc_status)
 973		goto exit;
 974
 975	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
 976			LPSS_IOSF_PMCSR, value2, mask2);
 977
 978	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
 979			LPSS_IOSF_PMCSR, value2, mask2);
 980
 981	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
 982			LPSS_IOSF_GPIODEF0, value1, mask1);
 983
 984	lpss_iosf_d3_entered = true;
 985
 986exit:
 987	mutex_unlock(&lpss_iosf_mutex);
 988}
 989
 990static void lpss_iosf_exit_d3_state(void)
 991{
 992	u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 |
 993		     LPSS_GPIODEF0_DMA_LLP;
 994	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
 995	u32 value2 = LPSS_PMCSR_D0;
 996	u32 mask2 = LPSS_PMCSR_Dx_MASK;
 997
 998	mutex_lock(&lpss_iosf_mutex);
 999
1000	if (!lpss_iosf_d3_entered)
1001		goto exit;
1002
1003	lpss_iosf_d3_entered = false;
1004
1005	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
1006			LPSS_IOSF_GPIODEF0, value1, mask1);
1007
1008	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
1009			LPSS_IOSF_PMCSR, value2, mask2);
1010
1011	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
1012			LPSS_IOSF_PMCSR, value2, mask2);
1013
1014exit:
1015	mutex_unlock(&lpss_iosf_mutex);
1016}
1017
1018static int acpi_lpss_suspend(struct device *dev, bool wakeup)
1019{
1020	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1021	int ret;
1022
1023	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
1024		acpi_lpss_save_ctx(dev, pdata);
1025
1026	ret = acpi_dev_suspend(dev, wakeup);
1027
1028	/*
1029	 * This call must be last in the sequence, otherwise PMC will return
1030	 * wrong status for devices being about to be powered off. See
1031	 * lpss_iosf_enter_d3_state() for further information.
1032	 */
1033	if (acpi_target_system_state() == ACPI_STATE_S0 &&
1034	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1035		lpss_iosf_enter_d3_state();
1036
1037	return ret;
1038}
1039
1040static int acpi_lpss_resume(struct device *dev)
1041{
1042	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1043	int ret;
1044
1045	/*
1046	 * This call is kept first to be in symmetry with
1047	 * acpi_lpss_runtime_suspend() one.
1048	 */
1049	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1050		lpss_iosf_exit_d3_state();
1051
1052	ret = acpi_dev_resume(dev);
1053	if (ret)
1054		return ret;
1055
1056	acpi_lpss_d3_to_d0_delay(pdata);
1057
1058	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
1059		acpi_lpss_restore_ctx(dev, pdata);
1060
1061	return 0;
1062}
1063
1064#ifdef CONFIG_PM_SLEEP
1065static int acpi_lpss_do_suspend_late(struct device *dev)
1066{
1067	int ret;
1068
1069	if (dev_pm_skip_suspend(dev))
1070		return 0;
1071
1072	ret = pm_generic_suspend_late(dev);
1073	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1074}
1075
1076static int acpi_lpss_suspend_late(struct device *dev)
1077{
1078	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1079
1080	if (pdata->dev_desc->resume_from_noirq)
1081		return 0;
1082
1083	return acpi_lpss_do_suspend_late(dev);
1084}
1085
1086static int acpi_lpss_suspend_noirq(struct device *dev)
1087{
1088	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1089	int ret;
1090
1091	if (pdata->dev_desc->resume_from_noirq) {
1092		/*
1093		 * The driver's ->suspend_late callback will be invoked by
1094		 * acpi_lpss_do_suspend_late(), with the assumption that the
1095		 * driver really wanted to run that code in ->suspend_noirq, but
1096		 * it could not run after acpi_dev_suspend() and the driver
1097		 * expected the latter to be called in the "late" phase.
1098		 */
1099		ret = acpi_lpss_do_suspend_late(dev);
1100		if (ret)
1101			return ret;
1102	}
1103
1104	return acpi_subsys_suspend_noirq(dev);
1105}
1106
1107static int acpi_lpss_do_resume_early(struct device *dev)
1108{
1109	int ret = acpi_lpss_resume(dev);
1110
1111	return ret ? ret : pm_generic_resume_early(dev);
1112}
1113
1114static int acpi_lpss_resume_early(struct device *dev)
1115{
1116	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1117
1118	if (pdata->dev_desc->resume_from_noirq)
1119		return 0;
1120
1121	if (dev_pm_skip_resume(dev))
1122		return 0;
1123
1124	return acpi_lpss_do_resume_early(dev);
1125}
1126
1127static int acpi_lpss_resume_noirq(struct device *dev)
1128{
1129	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1130	int ret;
1131
1132	/* Follow acpi_subsys_resume_noirq(). */
1133	if (dev_pm_skip_resume(dev))
1134		return 0;
1135
1136	ret = pm_generic_resume_noirq(dev);
1137	if (ret)
1138		return ret;
1139
1140	if (!pdata->dev_desc->resume_from_noirq)
1141		return 0;
1142
1143	/*
1144	 * The driver's ->resume_early callback will be invoked by
1145	 * acpi_lpss_do_resume_early(), with the assumption that the driver
1146	 * really wanted to run that code in ->resume_noirq, but it could not
1147	 * run before acpi_dev_resume() and the driver expected the latter to be
1148	 * called in the "early" phase.
1149	 */
1150	return acpi_lpss_do_resume_early(dev);
1151}
1152
1153static int acpi_lpss_do_restore_early(struct device *dev)
1154{
1155	int ret = acpi_lpss_resume(dev);
1156
1157	return ret ? ret : pm_generic_restore_early(dev);
1158}
1159
1160static int acpi_lpss_restore_early(struct device *dev)
1161{
1162	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1163
1164	if (pdata->dev_desc->resume_from_noirq)
1165		return 0;
1166
1167	return acpi_lpss_do_restore_early(dev);
1168}
1169
1170static int acpi_lpss_restore_noirq(struct device *dev)
1171{
1172	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1173	int ret;
1174
1175	ret = pm_generic_restore_noirq(dev);
1176	if (ret)
1177		return ret;
1178
1179	if (!pdata->dev_desc->resume_from_noirq)
1180		return 0;
1181
1182	/* This is analogous to what happens in acpi_lpss_resume_noirq(). */
1183	return acpi_lpss_do_restore_early(dev);
1184}
1185
1186static int acpi_lpss_do_poweroff_late(struct device *dev)
1187{
1188	int ret = pm_generic_poweroff_late(dev);
1189
1190	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1191}
1192
1193static int acpi_lpss_poweroff_late(struct device *dev)
1194{
1195	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1196
1197	if (dev_pm_skip_suspend(dev))
1198		return 0;
1199
1200	if (pdata->dev_desc->resume_from_noirq)
1201		return 0;
1202
1203	return acpi_lpss_do_poweroff_late(dev);
1204}
1205
1206static int acpi_lpss_poweroff_noirq(struct device *dev)
1207{
1208	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1209
1210	if (dev_pm_skip_suspend(dev))
1211		return 0;
1212
1213	if (pdata->dev_desc->resume_from_noirq) {
1214		/* This is analogous to the acpi_lpss_suspend_noirq() case. */
1215		int ret = acpi_lpss_do_poweroff_late(dev);
1216
1217		if (ret)
1218			return ret;
1219	}
1220
1221	return pm_generic_poweroff_noirq(dev);
1222}
1223#endif /* CONFIG_PM_SLEEP */
1224
1225static int acpi_lpss_runtime_suspend(struct device *dev)
1226{
1227	int ret = pm_generic_runtime_suspend(dev);
1228
1229	return ret ? ret : acpi_lpss_suspend(dev, true);
1230}
1231
1232static int acpi_lpss_runtime_resume(struct device *dev)
1233{
1234	int ret = acpi_lpss_resume(dev);
1235
1236	return ret ? ret : pm_generic_runtime_resume(dev);
1237}
1238#endif /* CONFIG_PM */
1239
1240static struct dev_pm_domain acpi_lpss_pm_domain = {
1241#ifdef CONFIG_PM
1242	.activate = acpi_lpss_activate,
1243	.dismiss = acpi_lpss_dismiss,
1244#endif
1245	.ops = {
1246#ifdef CONFIG_PM
1247#ifdef CONFIG_PM_SLEEP
1248		.prepare = acpi_subsys_prepare,
1249		.complete = acpi_subsys_complete,
1250		.suspend = acpi_subsys_suspend,
1251		.suspend_late = acpi_lpss_suspend_late,
1252		.suspend_noirq = acpi_lpss_suspend_noirq,
1253		.resume_noirq = acpi_lpss_resume_noirq,
1254		.resume_early = acpi_lpss_resume_early,
1255		.freeze = acpi_subsys_freeze,
1256		.poweroff = acpi_subsys_poweroff,
1257		.poweroff_late = acpi_lpss_poweroff_late,
1258		.poweroff_noirq = acpi_lpss_poweroff_noirq,
1259		.restore_noirq = acpi_lpss_restore_noirq,
1260		.restore_early = acpi_lpss_restore_early,
1261#endif
1262		.runtime_suspend = acpi_lpss_runtime_suspend,
1263		.runtime_resume = acpi_lpss_runtime_resume,
1264#endif
1265	},
1266};
1267
1268static int acpi_lpss_platform_notify(struct notifier_block *nb,
1269				     unsigned long action, void *data)
1270{
1271	struct platform_device *pdev = to_platform_device(data);
1272	struct lpss_private_data *pdata;
1273	struct acpi_device *adev;
1274	const struct acpi_device_id *id;
1275
1276	id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
1277	if (!id || !id->driver_data)
1278		return 0;
1279
1280	adev = ACPI_COMPANION(&pdev->dev);
1281	if (!adev)
1282		return 0;
1283
1284	pdata = acpi_driver_data(adev);
1285	if (!pdata)
1286		return 0;
1287
1288	if (pdata->mmio_base &&
1289	    pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
1290		dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
1291		return 0;
1292	}
1293
1294	switch (action) {
1295	case BUS_NOTIFY_BIND_DRIVER:
1296		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1297		break;
1298	case BUS_NOTIFY_DRIVER_NOT_BOUND:
1299	case BUS_NOTIFY_UNBOUND_DRIVER:
1300		dev_pm_domain_set(&pdev->dev, NULL);
1301		break;
1302	case BUS_NOTIFY_ADD_DEVICE:
1303		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1304		if (pdata->dev_desc->flags & LPSS_LTR)
1305			return sysfs_create_group(&pdev->dev.kobj,
1306						  &lpss_attr_group);
1307		break;
1308	case BUS_NOTIFY_DEL_DEVICE:
1309		if (pdata->dev_desc->flags & LPSS_LTR)
1310			sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
1311		dev_pm_domain_set(&pdev->dev, NULL);
1312		break;
1313	default:
1314		break;
1315	}
1316
1317	return 0;
1318}
1319
1320static struct notifier_block acpi_lpss_nb = {
1321	.notifier_call = acpi_lpss_platform_notify,
1322};
1323
1324static void acpi_lpss_bind(struct device *dev)
1325{
1326	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1327
1328	if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
1329		return;
1330
1331	if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
1332		dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
1333	else
1334		dev_err(dev, "MMIO size insufficient to access LTR\n");
1335}
1336
1337static void acpi_lpss_unbind(struct device *dev)
1338{
1339	dev->power.set_latency_tolerance = NULL;
1340}
1341
1342static struct acpi_scan_handler lpss_handler = {
1343	.ids = acpi_lpss_device_ids,
1344	.attach = acpi_lpss_create_device,
1345	.bind = acpi_lpss_bind,
1346	.unbind = acpi_lpss_unbind,
1347};
1348
1349void __init acpi_lpss_init(void)
1350{
1351	const struct x86_cpu_id *id;
1352	int ret;
1353
1354	ret = lpss_atom_clk_init();
1355	if (ret)
1356		return;
1357
1358	id = x86_match_cpu(lpss_cpu_ids);
1359	if (id)
1360		lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;
1361
1362	bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
1363	acpi_scan_add_handler(&lpss_handler);
1364}
1365
1366#else
1367
1368static struct acpi_scan_handler lpss_handler = {
1369	.ids = acpi_lpss_device_ids,
1370};
1371
1372void __init acpi_lpss_init(void)
1373{
1374	acpi_scan_add_handler(&lpss_handler);
1375}
1376
1377#endif /* CONFIG_X86_INTEL_LPSS */