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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * ACPI support for Intel Lynxpoint LPSS.4 *5 * Copyright (C) 2013, Intel Corporation6 * 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_LPSS31 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	0x0439#define LPSS_LTR_SIZE	0x1840 41/* Offsets relative to LPSS_PRIVATE_OFFSET */42#define LPSS_CLK_DIVIDER_DEF_MASK	(BIT(1) | BIT(16))43#define LPSS_RESETS			0x0444#define LPSS_RESETS_RESET_FUNC		BIT(0)45#define LPSS_RESETS_RESET_APB		BIT(1)46#define LPSS_GENERAL			0x0847#define LPSS_GENERAL_LTR_MODE_SW	BIT(2)48#define LPSS_GENERAL_UART_RTS_OVRD	BIT(3)49#define LPSS_SW_LTR			0x1050#define LPSS_AUTO_LTR			0x1451#define LPSS_LTR_SNOOP_REQ		BIT(15)52#define LPSS_LTR_SNOOP_MASK		0x0000FFFF53#define LPSS_LTR_SNOOP_LAT_1US		0x80054#define LPSS_LTR_SNOOP_LAT_32US		0xC0055#define LPSS_LTR_SNOOP_LAT_SHIFT	556#define LPSS_LTR_SNOOP_LAT_CUTOFF	300057#define LPSS_LTR_MAX_VAL		0x3FF58#define LPSS_TX_INT			0x2059#define LPSS_TX_INT_MASK		BIT(1)60 61#define LPSS_PRV_REG_COUNT		962 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 device71 * 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 can74 * 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. Moreover115 * 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 as118 * well as on ASuS T100TA transformer.119 *120 * This quirk overrides power state of entire LPSS island to keep DMA powered121 * 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			0xF4127#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 without160 * 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	/* Only call pwm_add_table for the first PWM controller */171	if (acpi_dev_uid_match(pdata->adev, 1))172		pwm_add_table(byt_pwm_lookup, ARRAY_SIZE(byt_pwm_lookup));173}174 175#define LPSS_I2C_ENABLE			0x6c176 177static void byt_i2c_setup(struct lpss_private_data *pdata)178{179	acpi_handle handle = pdata->adev->handle;180	unsigned long long shared_host = 0;181	acpi_status status;182	u64 uid;183 184	/* Expected to always be successfull, but better safe then sorry */185	if (!acpi_dev_uid_to_integer(pdata->adev, &uid) && uid) {186		/* Detect I2C bus shared with PUNIT and ignore its d3 status */187		status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host);188		if (ACPI_SUCCESS(status) && shared_host)189			pmc_atom_d3_mask &= ~(BIT_LPSS2_F1_I2C1 << (uid - 1));190	}191 192	lpss_deassert_reset(pdata);193 194	if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset))195		pdata->fixed_clk_rate = 133000000;196 197	writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);198}199 200/*201 * BSW PWM1 is used for backlight control by the i915 driver202 * BSW PWM2 is used for backlight control for fixed (etched into the glass)203 * touch controls on some models. These touch-controls have specialized204 * drivers which know they need the "pwm_soc_lpss_2" con-id.205 */206static struct pwm_lookup bsw_pwm_lookup[] = {207	PWM_LOOKUP_WITH_MODULE("80862288:00", 0, "0000:00:02.0",208			       "pwm_soc_backlight", 0, PWM_POLARITY_NORMAL,209			       "pwm-lpss-platform"),210	PWM_LOOKUP_WITH_MODULE("80862289:00", 0, NULL,211			       "pwm_soc_lpss_2", 0, PWM_POLARITY_NORMAL,212			       "pwm-lpss-platform"),213};214 215static void bsw_pwm_setup(struct lpss_private_data *pdata)216{217	/* Only call pwm_add_table for the first PWM controller */218	if (acpi_dev_uid_match(pdata->adev, 1))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_LTR229			| 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_LTR248			| 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 bsw_pwm2_dev_desc = {275	.flags = LPSS_SAVE_CTX_ONCE | LPSS_NO_D3_DELAY,276	.prv_offset = 0x800,277	.resume_from_noirq = true,278};279 280static const struct lpss_device_desc byt_uart_dev_desc = {281	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,282	.clk_con_id = "baudclk",283	.prv_offset = 0x800,284	.setup = lpss_uart_setup,285	.properties = uart_properties,286};287 288static const struct lpss_device_desc bsw_uart_dev_desc = {289	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX290			| LPSS_NO_D3_DELAY,291	.clk_con_id = "baudclk",292	.prv_offset = 0x800,293	.setup = lpss_uart_setup,294	.properties = uart_properties,295};296 297static const struct property_entry byt_spi_properties[] = {298	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_BYT_SSP),299	{ }300};301 302static const struct lpss_device_desc byt_spi_dev_desc = {303	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,304	.prv_offset = 0x400,305	.properties = byt_spi_properties,306};307 308static const struct lpss_device_desc byt_sdio_dev_desc = {309	.flags = LPSS_CLK,310};311 312static const struct lpss_device_desc byt_i2c_dev_desc = {313	.flags = LPSS_CLK | LPSS_SAVE_CTX,314	.prv_offset = 0x800,315	.setup = byt_i2c_setup,316	.resume_from_noirq = true,317};318 319static const struct lpss_device_desc bsw_i2c_dev_desc = {320	.flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,321	.prv_offset = 0x800,322	.setup = byt_i2c_setup,323	.resume_from_noirq = true,324};325 326static const struct property_entry bsw_spi_properties[] = {327	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_BSW_SSP),328	PROPERTY_ENTRY_U32("num-cs", 2),329	{ }330};331 332static const struct lpss_device_desc bsw_spi_dev_desc = {333	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX334			| LPSS_NO_D3_DELAY,335	.prv_offset = 0x400,336	.setup = lpss_deassert_reset,337	.properties = bsw_spi_properties,338};339 340static const struct x86_cpu_id lpss_cpu_ids[] = {341	X86_MATCH_VFM(INTEL_ATOM_SILVERMONT,	NULL),342	X86_MATCH_VFM(INTEL_ATOM_AIRMONT,	NULL),343	{}344};345 346#else347 348#define LPSS_ADDR(desc) (0UL)349 350#endif /* CONFIG_X86_INTEL_LPSS */351 352static const struct acpi_device_id acpi_lpss_device_ids[] = {353	/* Generic LPSS devices */354	{ "INTL9C60", LPSS_ADDR(lpss_dma_desc) },355 356	/* Lynxpoint LPSS devices */357	{ "INT33C0", LPSS_ADDR(lpt_spi_dev_desc) },358	{ "INT33C1", LPSS_ADDR(lpt_spi_dev_desc) },359	{ "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },360	{ "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },361	{ "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },362	{ "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },363	{ "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },364 365	/* BayTrail LPSS devices */366	{ "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },367	{ "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },368	{ "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },369	{ "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },370	{ "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },371 372	/* Braswell LPSS devices */373	{ "80862286", LPSS_ADDR(lpss_dma_desc) },374	{ "80862288", LPSS_ADDR(bsw_pwm_dev_desc) },375	{ "80862289", LPSS_ADDR(bsw_pwm2_dev_desc) },376	{ "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },377	{ "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },378	{ "808622C0", LPSS_ADDR(lpss_dma_desc) },379	{ "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) },380 381	/* Broadwell LPSS devices */382	{ "INT3430", LPSS_ADDR(lpt_spi_dev_desc) },383	{ "INT3431", LPSS_ADDR(lpt_spi_dev_desc) },384	{ "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },385	{ "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },386	{ "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },387	{ "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },388	{ "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },389 390	/* Wildcat Point LPSS devices */391	{ "INT3438", LPSS_ADDR(lpt_spi_dev_desc) },392 393	{ }394};395 396#ifdef CONFIG_X86_INTEL_LPSS397 398/* LPSS main clock device. */399static struct platform_device *lpss_clk_dev;400 401static inline void lpt_register_clock_device(void)402{403	lpss_clk_dev = platform_device_register_simple("clk-lpss-atom",404						       PLATFORM_DEVID_NONE,405						       NULL, 0);406}407 408static int register_device_clock(struct acpi_device *adev,409				 struct lpss_private_data *pdata)410{411	const struct lpss_device_desc *dev_desc = pdata->dev_desc;412	const char *devname = dev_name(&adev->dev);413	struct clk *clk;414	struct lpss_clk_data *clk_data;415	const char *parent, *clk_name;416	void __iomem *prv_base;417 418	if (!lpss_clk_dev)419		lpt_register_clock_device();420 421	if (IS_ERR(lpss_clk_dev))422		return PTR_ERR(lpss_clk_dev);423 424	clk_data = platform_get_drvdata(lpss_clk_dev);425	if (!clk_data)426		return -ENODEV;427	clk = clk_data->clk;428 429	if (!pdata->mmio_base430	    || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)431		return -ENODATA;432 433	parent = clk_data->name;434	prv_base = pdata->mmio_base + dev_desc->prv_offset;435 436	if (pdata->fixed_clk_rate) {437		clk = clk_register_fixed_rate(NULL, devname, parent, 0,438					      pdata->fixed_clk_rate);439		goto out;440	}441 442	if (dev_desc->flags & LPSS_CLK_GATE) {443		clk = clk_register_gate(NULL, devname, parent, 0,444					prv_base, 0, 0, NULL);445		parent = devname;446	}447 448	if (dev_desc->flags & LPSS_CLK_DIVIDER) {449		/* Prevent division by zero */450		if (!readl(prv_base))451			writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);452 453		clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);454		if (!clk_name)455			return -ENOMEM;456		clk = clk_register_fractional_divider(NULL, clk_name, parent,457						      0, prv_base, 1, 15, 16, 15,458						      CLK_FRAC_DIVIDER_POWER_OF_TWO_PS,459						      NULL);460		parent = clk_name;461 462		clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);463		if (!clk_name) {464			kfree(parent);465			return -ENOMEM;466		}467		clk = clk_register_gate(NULL, clk_name, parent,468					CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,469					prv_base, 31, 0, NULL);470		kfree(parent);471		kfree(clk_name);472	}473out:474	if (IS_ERR(clk))475		return PTR_ERR(clk);476 477	pdata->clk = clk;478	clk_register_clkdev(clk, dev_desc->clk_con_id, devname);479	return 0;480}481 482struct lpss_device_links {483	const char *supplier_hid;484	const char *supplier_uid;485	const char *consumer_hid;486	const char *consumer_uid;487	u32 flags;488	const struct dmi_system_id *dep_missing_ids;489};490 491/* Please keep this list sorted alphabetically by vendor and model */492static const struct dmi_system_id i2c1_dep_missing_dmi_ids[] = {493	{494		.matches = {495			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),496			DMI_MATCH(DMI_PRODUCT_NAME, "T200TA"),497		},498	},499	{}500};501 502/*503 * The _DEP method is used to identify dependencies but instead of creating504 * device links for every handle in _DEP, only links in the following list are505 * created. That is necessary because, in the general case, _DEP can refer to506 * devices that might not have drivers, or that are on different buses, or where507 * the supplier is not enumerated until after the consumer is probed.508 */509static const struct lpss_device_links lpss_device_links[] = {510	/* CHT External sdcard slot controller depends on PMIC I2C ctrl */511	{"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME},512	/* CHT iGPU depends on PMIC I2C controller */513	{"808622C1", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},514	/* BYT iGPU depends on the Embedded Controller I2C controller (UID 1) */515	{"80860F41", "1", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME,516	 i2c1_dep_missing_dmi_ids},517	/* BYT CR iGPU depends on PMIC I2C controller (UID 5 on CR) */518	{"80860F41", "5", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},519	/* BYT iGPU depends on PMIC I2C controller (UID 7 on non CR) */520	{"80860F41", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},521};522 523static bool acpi_lpss_is_supplier(struct acpi_device *adev,524				  const struct lpss_device_links *link)525{526	return acpi_dev_hid_uid_match(adev, link->supplier_hid, link->supplier_uid);527}528 529static bool acpi_lpss_is_consumer(struct acpi_device *adev,530				  const struct lpss_device_links *link)531{532	return acpi_dev_hid_uid_match(adev, link->consumer_hid, link->consumer_uid);533}534 535struct hid_uid {536	const char *hid;537	const char *uid;538};539 540static int match_hid_uid(struct device *dev, const void *data)541{542	struct acpi_device *adev = ACPI_COMPANION(dev);543	const struct hid_uid *id = data;544 545	if (!adev)546		return 0;547 548	return acpi_dev_hid_uid_match(adev, id->hid, id->uid);549}550 551static struct device *acpi_lpss_find_device(const char *hid, const char *uid)552{553	struct device *dev;554 555	struct hid_uid data = {556		.hid = hid,557		.uid = uid,558	};559 560	dev = bus_find_device(&platform_bus_type, NULL, &data, match_hid_uid);561	if (dev)562		return dev;563 564	return bus_find_device(&pci_bus_type, NULL, &data, match_hid_uid);565}566 567static void acpi_lpss_link_consumer(struct device *dev1,568				    const struct lpss_device_links *link)569{570	struct device *dev2;571 572	dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid);573	if (!dev2)574		return;575 576	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))577	    || acpi_device_dep(ACPI_HANDLE(dev2), ACPI_HANDLE(dev1)))578		device_link_add(dev2, dev1, link->flags);579 580	put_device(dev2);581}582 583static void acpi_lpss_link_supplier(struct device *dev1,584				    const struct lpss_device_links *link)585{586	struct device *dev2;587 588	dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid);589	if (!dev2)590		return;591 592	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))593	    || acpi_device_dep(ACPI_HANDLE(dev1), ACPI_HANDLE(dev2)))594		device_link_add(dev1, dev2, link->flags);595 596	put_device(dev2);597}598 599static void acpi_lpss_create_device_links(struct acpi_device *adev,600					  struct platform_device *pdev)601{602	int i;603 604	for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) {605		const struct lpss_device_links *link = &lpss_device_links[i];606 607		if (acpi_lpss_is_supplier(adev, link))608			acpi_lpss_link_consumer(&pdev->dev, link);609 610		if (acpi_lpss_is_consumer(adev, link))611			acpi_lpss_link_supplier(&pdev->dev, link);612	}613}614 615static int acpi_lpss_create_device(struct acpi_device *adev,616				   const struct acpi_device_id *id)617{618	const struct lpss_device_desc *dev_desc;619	struct lpss_private_data *pdata;620	struct resource_entry *rentry;621	struct list_head resource_list;622	struct platform_device *pdev;623	int ret;624 625	dev_desc = (const struct lpss_device_desc *)id->driver_data;626	if (!dev_desc)627		return -EINVAL;628 629	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);630	if (!pdata)631		return -ENOMEM;632 633	INIT_LIST_HEAD(&resource_list);634	ret = acpi_dev_get_memory_resources(adev, &resource_list);635	if (ret < 0)636		goto err_out;637 638	rentry = list_first_entry_or_null(&resource_list, struct resource_entry, node);639	if (rentry) {640		if (dev_desc->prv_size_override)641			pdata->mmio_size = dev_desc->prv_size_override;642		else643			pdata->mmio_size = resource_size(rentry->res);644		pdata->mmio_base = ioremap(rentry->res->start, pdata->mmio_size);645	}646 647	acpi_dev_free_resource_list(&resource_list);648 649	if (!pdata->mmio_base) {650		/* Avoid acpi_bus_attach() instantiating a pdev for this dev. */651		adev->pnp.type.platform_id = 0;652		goto out_free;653	}654 655	pdata->adev = adev;656	pdata->dev_desc = dev_desc;657 658	if (dev_desc->setup)659		dev_desc->setup(pdata);660 661	if (dev_desc->flags & LPSS_CLK) {662		ret = register_device_clock(adev, pdata);663		if (ret)664			goto out_free;665	}666 667	/*668	 * This works around a known issue in ACPI tables where LPSS devices669	 * have _PS0 and _PS3 without _PSC (and no power resources), so670	 * acpi_bus_init_power() will assume that the BIOS has put them into D0.671	 */672	acpi_device_fix_up_power(adev);673 674	adev->driver_data = pdata;675	pdev = acpi_create_platform_device(adev, dev_desc->properties);676	if (IS_ERR_OR_NULL(pdev)) {677		adev->driver_data = NULL;678		ret = PTR_ERR(pdev);679		goto err_out;680	}681 682	acpi_lpss_create_device_links(adev, pdev);683	return 1;684 685out_free:686	/* Skip the device, but continue the namespace scan */687	ret = 0;688err_out:689	kfree(pdata);690	return ret;691}692 693static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)694{695	return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);696}697 698static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,699			     unsigned int reg)700{701	writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);702}703 704static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)705{706	struct acpi_device *adev = ACPI_COMPANION(dev);707	struct lpss_private_data *pdata;708	unsigned long flags;709	int ret;710 711	if (WARN_ON(!adev))712		return -ENODEV;713 714	spin_lock_irqsave(&dev->power.lock, flags);715	if (pm_runtime_suspended(dev)) {716		ret = -EAGAIN;717		goto out;718	}719	pdata = acpi_driver_data(adev);720	if (WARN_ON(!pdata || !pdata->mmio_base)) {721		ret = -ENODEV;722		goto out;723	}724	*val = __lpss_reg_read(pdata, reg);725	ret = 0;726 727 out:728	spin_unlock_irqrestore(&dev->power.lock, flags);729	return ret;730}731 732static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,733			     char *buf)734{735	u32 ltr_value = 0;736	unsigned int reg;737	int ret;738 739	reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;740	ret = lpss_reg_read(dev, reg, &ltr_value);741	if (ret)742		return ret;743 744	return sysfs_emit(buf, "%08x\n", ltr_value);745}746 747static ssize_t lpss_ltr_mode_show(struct device *dev,748				  struct device_attribute *attr, char *buf)749{750	u32 ltr_mode = 0;751	char *outstr;752	int ret;753 754	ret = lpss_reg_read(dev, LPSS_GENERAL, &ltr_mode);755	if (ret)756		return ret;757 758	outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";759	return sprintf(buf, "%s\n", outstr);760}761 762static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);763static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);764static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);765 766static struct attribute *lpss_attrs[] = {767	&dev_attr_auto_ltr.attr,768	&dev_attr_sw_ltr.attr,769	&dev_attr_ltr_mode.attr,770	NULL,771};772 773static const struct attribute_group lpss_attr_group = {774	.attrs = lpss_attrs,775	.name = "lpss_ltr",776};777 778static void acpi_lpss_set_ltr(struct device *dev, s32 val)779{780	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));781	u32 ltr_mode, ltr_val;782 783	ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);784	if (val < 0) {785		if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {786			ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;787			__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);788		}789		return;790	}791	ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;792	if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {793		ltr_val |= LPSS_LTR_SNOOP_LAT_32US;794		val = LPSS_LTR_MAX_VAL;795	} else if (val > LPSS_LTR_MAX_VAL) {796		ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;797		val >>= LPSS_LTR_SNOOP_LAT_SHIFT;798	} else {799		ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;800	}801	ltr_val |= val;802	__lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);803	if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {804		ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;805		__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);806	}807}808 809#ifdef CONFIG_PM810/**811 * acpi_lpss_save_ctx() - Save the private registers of LPSS device812 * @dev: LPSS device813 * @pdata: pointer to the private data of the LPSS device814 *815 * Most LPSS devices have private registers which may loose their context when816 * the device is powered down. acpi_lpss_save_ctx() saves those registers into817 * prv_reg_ctx array.818 */819static void acpi_lpss_save_ctx(struct device *dev,820			       struct lpss_private_data *pdata)821{822	unsigned int i;823 824	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {825		unsigned long offset = i * sizeof(u32);826 827		pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);828		dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",829			pdata->prv_reg_ctx[i], offset);830	}831}832 833/**834 * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device835 * @dev: LPSS device836 * @pdata: pointer to the private data of the LPSS device837 *838 * Restores the registers that were previously stored with acpi_lpss_save_ctx().839 */840static void acpi_lpss_restore_ctx(struct device *dev,841				  struct lpss_private_data *pdata)842{843	unsigned int i;844 845	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {846		unsigned long offset = i * sizeof(u32);847 848		__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);849		dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",850			pdata->prv_reg_ctx[i], offset);851	}852}853 854static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)855{856	/*857	 * The following delay is needed or the subsequent write operations may858	 * fail. The LPSS devices are actually PCI devices and the PCI spec859	 * expects 10ms delay before the device can be accessed after D3 to D0860	 * transition. However some platforms like BSW does not need this delay.861	 */862	unsigned int delay = 10;	/* default 10ms delay */863 864	if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)865		delay = 0;866 867	msleep(delay);868}869 870static int acpi_lpss_activate(struct device *dev)871{872	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));873	int ret;874 875	ret = acpi_dev_resume(dev);876	if (ret)877		return ret;878 879	acpi_lpss_d3_to_d0_delay(pdata);880 881	/*882	 * This is called only on ->probe() stage where a device is either in883	 * known state defined by BIOS or most likely powered off. Due to this884	 * we have to deassert reset line to be sure that ->probe() will885	 * recognize the device.886	 */887	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))888		lpss_deassert_reset(pdata);889 890	if (pdata->dev_desc->flags & LPSS_SAVE_CTX_ONCE)891		acpi_lpss_save_ctx(dev, pdata);892 893	return 0;894}895 896static void acpi_lpss_dismiss(struct device *dev)897{898	acpi_dev_suspend(dev, false);899}900 901/* IOSF SB for LPSS island */902#define LPSS_IOSF_UNIT_LPIOEP		0xA0903#define LPSS_IOSF_UNIT_LPIO1		0xAB904#define LPSS_IOSF_UNIT_LPIO2		0xAC905 906#define LPSS_IOSF_PMCSR			0x84907#define LPSS_PMCSR_D0			0908#define LPSS_PMCSR_D3hot		3909#define LPSS_PMCSR_Dx_MASK		GENMASK(1, 0)910 911#define LPSS_IOSF_GPIODEF0		0x154912#define LPSS_GPIODEF0_DMA1_D3		BIT(2)913#define LPSS_GPIODEF0_DMA2_D3		BIT(3)914#define LPSS_GPIODEF0_DMA_D3_MASK	GENMASK(3, 2)915#define LPSS_GPIODEF0_DMA_LLP		BIT(13)916 917static DEFINE_MUTEX(lpss_iosf_mutex);918static bool lpss_iosf_d3_entered = true;919 920static void lpss_iosf_enter_d3_state(void)921{922	u32 value1 = 0;923	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;924	u32 value2 = LPSS_PMCSR_D3hot;925	u32 mask2 = LPSS_PMCSR_Dx_MASK;926	/*927	 * PMC provides an information about actual status of the LPSS devices.928	 * Here we read the values related to LPSS power island, i.e. LPSS929	 * devices, excluding both LPSS DMA controllers, along with SCC domain.930	 */931	u32 func_dis, d3_sts_0, pmc_status;932	int ret;933 934	ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);935	if (ret)936		return;937 938	mutex_lock(&lpss_iosf_mutex);939 940	ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);941	if (ret)942		goto exit;943 944	/*945	 * Get the status of entire LPSS power island per device basis.946	 * Shutdown both LPSS DMA controllers if and only if all other devices947	 * are already in D3hot.948	 */949	pmc_status = (~(d3_sts_0 | func_dis)) & pmc_atom_d3_mask;950	if (pmc_status)951		goto exit;952 953	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,954			LPSS_IOSF_PMCSR, value2, mask2);955 956	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,957			LPSS_IOSF_PMCSR, value2, mask2);958 959	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,960			LPSS_IOSF_GPIODEF0, value1, mask1);961 962	lpss_iosf_d3_entered = true;963 964exit:965	mutex_unlock(&lpss_iosf_mutex);966}967 968static void lpss_iosf_exit_d3_state(void)969{970	u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 |971		     LPSS_GPIODEF0_DMA_LLP;972	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;973	u32 value2 = LPSS_PMCSR_D0;974	u32 mask2 = LPSS_PMCSR_Dx_MASK;975 976	mutex_lock(&lpss_iosf_mutex);977 978	if (!lpss_iosf_d3_entered)979		goto exit;980 981	lpss_iosf_d3_entered = false;982 983	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,984			LPSS_IOSF_GPIODEF0, value1, mask1);985 986	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,987			LPSS_IOSF_PMCSR, value2, mask2);988 989	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,990			LPSS_IOSF_PMCSR, value2, mask2);991 992exit:993	mutex_unlock(&lpss_iosf_mutex);994}995 996static int acpi_lpss_suspend(struct device *dev, bool wakeup)997{998	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));999	int ret;1000 1001	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)1002		acpi_lpss_save_ctx(dev, pdata);1003 1004	ret = acpi_dev_suspend(dev, wakeup);1005 1006	/*1007	 * This call must be last in the sequence, otherwise PMC will return1008	 * wrong status for devices being about to be powered off. See1009	 * lpss_iosf_enter_d3_state() for further information.1010	 */1011	if (acpi_target_system_state() == ACPI_STATE_S0 &&1012	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())1013		lpss_iosf_enter_d3_state();1014 1015	return ret;1016}1017 1018static int acpi_lpss_resume(struct device *dev)1019{1020	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));1021	int ret;1022 1023	/*1024	 * This call is kept first to be in symmetry with1025	 * acpi_lpss_runtime_suspend() one.1026	 */1027	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())1028		lpss_iosf_exit_d3_state();1029 1030	ret = acpi_dev_resume(dev);1031	if (ret)1032		return ret;1033 1034	acpi_lpss_d3_to_d0_delay(pdata);1035 1036	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))1037		acpi_lpss_restore_ctx(dev, pdata);1038 1039	return 0;1040}1041 1042#ifdef CONFIG_PM_SLEEP1043static int acpi_lpss_do_suspend_late(struct device *dev)1044{1045	int ret;1046 1047	if (dev_pm_skip_suspend(dev))1048		return 0;1049 1050	ret = pm_generic_suspend_late(dev);1051	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));1052}1053 1054static int acpi_lpss_suspend_late(struct device *dev)1055{1056	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));1057 1058	if (pdata->dev_desc->resume_from_noirq)1059		return 0;1060 1061	return acpi_lpss_do_suspend_late(dev);1062}1063 1064static int acpi_lpss_suspend_noirq(struct device *dev)1065{1066	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));1067	int ret;1068 1069	if (pdata->dev_desc->resume_from_noirq) {1070		/*1071		 * The driver's ->suspend_late callback will be invoked by1072		 * acpi_lpss_do_suspend_late(), with the assumption that the1073		 * driver really wanted to run that code in ->suspend_noirq, but1074		 * it could not run after acpi_dev_suspend() and the driver1075		 * expected the latter to be called in the "late" phase.1076		 */1077		ret = acpi_lpss_do_suspend_late(dev);1078		if (ret)1079			return ret;1080	}1081 1082	return acpi_subsys_suspend_noirq(dev);1083}1084 1085static int acpi_lpss_do_resume_early(struct device *dev)1086{1087	int ret = acpi_lpss_resume(dev);1088 1089	return ret ? ret : pm_generic_resume_early(dev);1090}1091 1092static int acpi_lpss_resume_early(struct device *dev)1093{1094	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));1095 1096	if (pdata->dev_desc->resume_from_noirq)1097		return 0;1098 1099	if (dev_pm_skip_resume(dev))1100		return 0;1101 1102	return acpi_lpss_do_resume_early(dev);1103}1104 1105static int acpi_lpss_resume_noirq(struct device *dev)1106{1107	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));1108	int ret;1109 1110	/* Follow acpi_subsys_resume_noirq(). */1111	if (dev_pm_skip_resume(dev))1112		return 0;1113 1114	ret = pm_generic_resume_noirq(dev);1115	if (ret)1116		return ret;1117 1118	if (!pdata->dev_desc->resume_from_noirq)1119		return 0;1120 1121	/*1122	 * The driver's ->resume_early callback will be invoked by1123	 * acpi_lpss_do_resume_early(), with the assumption that the driver1124	 * really wanted to run that code in ->resume_noirq, but it could not1125	 * run before acpi_dev_resume() and the driver expected the latter to be1126	 * called in the "early" phase.1127	 */1128	return acpi_lpss_do_resume_early(dev);1129}1130 1131static int acpi_lpss_do_restore_early(struct device *dev)1132{1133	int ret = acpi_lpss_resume(dev);1134 1135	return ret ? ret : pm_generic_restore_early(dev);1136}1137 1138static int acpi_lpss_restore_early(struct device *dev)1139{1140	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));1141 1142	if (pdata->dev_desc->resume_from_noirq)1143		return 0;1144 1145	return acpi_lpss_do_restore_early(dev);1146}1147 1148static int acpi_lpss_restore_noirq(struct device *dev)1149{1150	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));1151	int ret;1152 1153	ret = pm_generic_restore_noirq(dev);1154	if (ret)1155		return ret;1156 1157	if (!pdata->dev_desc->resume_from_noirq)1158		return 0;1159 1160	/* This is analogous to what happens in acpi_lpss_resume_noirq(). */1161	return acpi_lpss_do_restore_early(dev);1162}1163 1164static int acpi_lpss_do_poweroff_late(struct device *dev)1165{1166	int ret = pm_generic_poweroff_late(dev);1167 1168	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));1169}1170 1171static int acpi_lpss_poweroff_late(struct device *dev)1172{1173	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));1174 1175	if (dev_pm_skip_suspend(dev))1176		return 0;1177 1178	if (pdata->dev_desc->resume_from_noirq)1179		return 0;1180 1181	return acpi_lpss_do_poweroff_late(dev);1182}1183 1184static int acpi_lpss_poweroff_noirq(struct device *dev)1185{1186	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));1187 1188	if (dev_pm_skip_suspend(dev))1189		return 0;1190 1191	if (pdata->dev_desc->resume_from_noirq) {1192		/* This is analogous to the acpi_lpss_suspend_noirq() case. */1193		int ret = acpi_lpss_do_poweroff_late(dev);1194 1195		if (ret)1196			return ret;1197	}1198 1199	return pm_generic_poweroff_noirq(dev);1200}1201#endif /* CONFIG_PM_SLEEP */1202 1203static int acpi_lpss_runtime_suspend(struct device *dev)1204{1205	int ret = pm_generic_runtime_suspend(dev);1206 1207	return ret ? ret : acpi_lpss_suspend(dev, true);1208}1209 1210static int acpi_lpss_runtime_resume(struct device *dev)1211{1212	int ret = acpi_lpss_resume(dev);1213 1214	return ret ? ret : pm_generic_runtime_resume(dev);1215}1216#endif /* CONFIG_PM */1217 1218static struct dev_pm_domain acpi_lpss_pm_domain = {1219#ifdef CONFIG_PM1220	.activate = acpi_lpss_activate,1221	.dismiss = acpi_lpss_dismiss,1222#endif1223	.ops = {1224#ifdef CONFIG_PM1225#ifdef CONFIG_PM_SLEEP1226		.prepare = acpi_subsys_prepare,1227		.complete = acpi_subsys_complete,1228		.suspend = acpi_subsys_suspend,1229		.suspend_late = acpi_lpss_suspend_late,1230		.suspend_noirq = acpi_lpss_suspend_noirq,1231		.resume_noirq = acpi_lpss_resume_noirq,1232		.resume_early = acpi_lpss_resume_early,1233		.freeze = acpi_subsys_freeze,1234		.poweroff = acpi_subsys_poweroff,1235		.poweroff_late = acpi_lpss_poweroff_late,1236		.poweroff_noirq = acpi_lpss_poweroff_noirq,1237		.restore_noirq = acpi_lpss_restore_noirq,1238		.restore_early = acpi_lpss_restore_early,1239#endif1240		.runtime_suspend = acpi_lpss_runtime_suspend,1241		.runtime_resume = acpi_lpss_runtime_resume,1242#endif1243	},1244};1245 1246static int acpi_lpss_platform_notify(struct notifier_block *nb,1247				     unsigned long action, void *data)1248{1249	struct platform_device *pdev = to_platform_device(data);1250	struct lpss_private_data *pdata;1251	struct acpi_device *adev;1252	const struct acpi_device_id *id;1253 1254	id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);1255	if (!id || !id->driver_data)1256		return 0;1257 1258	adev = ACPI_COMPANION(&pdev->dev);1259	if (!adev)1260		return 0;1261 1262	pdata = acpi_driver_data(adev);1263	if (!pdata)1264		return 0;1265 1266	if (pdata->mmio_base &&1267	    pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {1268		dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");1269		return 0;1270	}1271 1272	switch (action) {1273	case BUS_NOTIFY_BIND_DRIVER:1274		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);1275		break;1276	case BUS_NOTIFY_DRIVER_NOT_BOUND:1277	case BUS_NOTIFY_UNBOUND_DRIVER:1278		dev_pm_domain_set(&pdev->dev, NULL);1279		break;1280	case BUS_NOTIFY_ADD_DEVICE:1281		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);1282		if (pdata->dev_desc->flags & LPSS_LTR)1283			return sysfs_create_group(&pdev->dev.kobj,1284						  &lpss_attr_group);1285		break;1286	case BUS_NOTIFY_DEL_DEVICE:1287		if (pdata->dev_desc->flags & LPSS_LTR)1288			sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);1289		dev_pm_domain_set(&pdev->dev, NULL);1290		break;1291	default:1292		break;1293	}1294 1295	return 0;1296}1297 1298static struct notifier_block acpi_lpss_nb = {1299	.notifier_call = acpi_lpss_platform_notify,1300};1301 1302static void acpi_lpss_bind(struct device *dev)1303{1304	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));1305 1306	if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))1307		return;1308 1309	if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)1310		dev->power.set_latency_tolerance = acpi_lpss_set_ltr;1311	else1312		dev_err(dev, "MMIO size insufficient to access LTR\n");1313}1314 1315static void acpi_lpss_unbind(struct device *dev)1316{1317	dev->power.set_latency_tolerance = NULL;1318}1319 1320static struct acpi_scan_handler lpss_handler = {1321	.ids = acpi_lpss_device_ids,1322	.attach = acpi_lpss_create_device,1323	.bind = acpi_lpss_bind,1324	.unbind = acpi_lpss_unbind,1325};1326 1327void __init acpi_lpss_init(void)1328{1329	const struct x86_cpu_id *id;1330	int ret;1331 1332	ret = lpss_atom_clk_init();1333	if (ret)1334		return;1335 1336	id = x86_match_cpu(lpss_cpu_ids);1337	if (id)1338		lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;1339 1340	bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);1341	acpi_scan_add_handler(&lpss_handler);1342}1343 1344#else1345 1346static struct acpi_scan_handler lpss_handler = {1347	.ids = acpi_lpss_device_ids,1348};1349 1350void __init acpi_lpss_init(void)1351{1352	acpi_scan_add_handler(&lpss_handler);1353}1354 1355#endif /* CONFIG_X86_INTEL_LPSS */1356