xref: /openbmc/linux/drivers/acpi/acpi_lpss.c (revision 2169e6da)
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/err.h>
14 #include <linux/io.h>
15 #include <linux/mutex.h>
16 #include <linux/pci.h>
17 #include <linux/platform_device.h>
18 #include <linux/platform_data/x86/clk-lpss.h>
19 #include <linux/platform_data/x86/pmc_atom.h>
20 #include <linux/pm_domain.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/pwm.h>
23 #include <linux/suspend.h>
24 #include <linux/delay.h>
25 
26 #include "internal.h"
27 
28 ACPI_MODULE_NAME("acpi_lpss");
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 #define LPSS_NO_D3_DELAY		BIT(5)
70 
71 /* Crystal Cove PMIC shares same ACPI ID between different platforms */
72 #define BYT_CRC_HRV			2
73 #define CHT_CRC_HRV			3
74 
75 struct lpss_private_data;
76 
77 struct lpss_device_desc {
78 	unsigned int flags;
79 	const char *clk_con_id;
80 	unsigned int prv_offset;
81 	size_t prv_size_override;
82 	struct property_entry *properties;
83 	void (*setup)(struct lpss_private_data *pdata);
84 	bool resume_from_noirq;
85 };
86 
87 static const struct lpss_device_desc lpss_dma_desc = {
88 	.flags = LPSS_CLK,
89 };
90 
91 struct lpss_private_data {
92 	struct acpi_device *adev;
93 	void __iomem *mmio_base;
94 	resource_size_t mmio_size;
95 	unsigned int fixed_clk_rate;
96 	struct clk *clk;
97 	const struct lpss_device_desc *dev_desc;
98 	u32 prv_reg_ctx[LPSS_PRV_REG_COUNT];
99 };
100 
101 /* Devices which need to be in D3 before lpss_iosf_enter_d3_state() proceeds */
102 static u32 pmc_atom_d3_mask = 0xfe000ffe;
103 
104 /* LPSS run time quirks */
105 static unsigned int lpss_quirks;
106 
107 /*
108  * LPSS_QUIRK_ALWAYS_POWER_ON: override power state for LPSS DMA device.
109  *
110  * The LPSS DMA controller has neither _PS0 nor _PS3 method. Moreover
111  * it can be powered off automatically whenever the last LPSS device goes down.
112  * In case of no power any access to the DMA controller will hang the system.
113  * The behaviour is reproduced on some HP laptops based on Intel BayTrail as
114  * well as on ASuS T100TA transformer.
115  *
116  * This quirk overrides power state of entire LPSS island to keep DMA powered
117  * on whenever we have at least one other device in use.
118  */
119 #define LPSS_QUIRK_ALWAYS_POWER_ON	BIT(0)
120 
121 /* UART Component Parameter Register */
122 #define LPSS_UART_CPR			0xF4
123 #define LPSS_UART_CPR_AFCE		BIT(4)
124 
125 static void lpss_uart_setup(struct lpss_private_data *pdata)
126 {
127 	unsigned int offset;
128 	u32 val;
129 
130 	offset = pdata->dev_desc->prv_offset + LPSS_TX_INT;
131 	val = readl(pdata->mmio_base + offset);
132 	writel(val | LPSS_TX_INT_MASK, pdata->mmio_base + offset);
133 
134 	val = readl(pdata->mmio_base + LPSS_UART_CPR);
135 	if (!(val & LPSS_UART_CPR_AFCE)) {
136 		offset = pdata->dev_desc->prv_offset + LPSS_GENERAL;
137 		val = readl(pdata->mmio_base + offset);
138 		val |= LPSS_GENERAL_UART_RTS_OVRD;
139 		writel(val, pdata->mmio_base + offset);
140 	}
141 }
142 
143 static void lpss_deassert_reset(struct lpss_private_data *pdata)
144 {
145 	unsigned int offset;
146 	u32 val;
147 
148 	offset = pdata->dev_desc->prv_offset + LPSS_RESETS;
149 	val = readl(pdata->mmio_base + offset);
150 	val |= LPSS_RESETS_RESET_APB | LPSS_RESETS_RESET_FUNC;
151 	writel(val, pdata->mmio_base + offset);
152 }
153 
154 /*
155  * BYT PWM used for backlight control by the i915 driver on systems without
156  * the Crystal Cove PMIC.
157  */
158 static struct pwm_lookup byt_pwm_lookup[] = {
159 	PWM_LOOKUP_WITH_MODULE("80860F09:00", 0, "0000:00:02.0",
160 			       "pwm_backlight", 0, PWM_POLARITY_NORMAL,
161 			       "pwm-lpss-platform"),
162 };
163 
164 static void byt_pwm_setup(struct lpss_private_data *pdata)
165 {
166 	struct acpi_device *adev = pdata->adev;
167 
168 	/* Only call pwm_add_table for the first PWM controller */
169 	if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "1"))
170 		return;
171 
172 	if (!acpi_dev_present("INT33FD", NULL, BYT_CRC_HRV))
173 		pwm_add_table(byt_pwm_lookup, ARRAY_SIZE(byt_pwm_lookup));
174 }
175 
176 #define LPSS_I2C_ENABLE			0x6c
177 
178 static void byt_i2c_setup(struct lpss_private_data *pdata)
179 {
180 	const char *uid_str = acpi_device_uid(pdata->adev);
181 	acpi_handle handle = pdata->adev->handle;
182 	unsigned long long shared_host = 0;
183 	acpi_status status;
184 	long uid = 0;
185 
186 	/* Expected to always be true, but better safe then sorry */
187 	if (uid_str)
188 		uid = simple_strtol(uid_str, NULL, 10);
189 
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 && uid)
193 		pmc_atom_d3_mask &= ~(BIT_LPSS2_F1_I2C1 << (uid - 1));
194 
195 	lpss_deassert_reset(pdata);
196 
197 	if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset))
198 		pdata->fixed_clk_rate = 133000000;
199 
200 	writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
201 }
202 
203 /* BSW PWM used for backlight control by the i915 driver */
204 static struct pwm_lookup bsw_pwm_lookup[] = {
205 	PWM_LOOKUP_WITH_MODULE("80862288:00", 0, "0000:00:02.0",
206 			       "pwm_backlight", 0, PWM_POLARITY_NORMAL,
207 			       "pwm-lpss-platform"),
208 };
209 
210 static void bsw_pwm_setup(struct lpss_private_data *pdata)
211 {
212 	struct acpi_device *adev = pdata->adev;
213 
214 	/* Only call pwm_add_table for the first PWM controller */
215 	if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "1"))
216 		return;
217 
218 	pwm_add_table(bsw_pwm_lookup, ARRAY_SIZE(bsw_pwm_lookup));
219 }
220 
221 static const struct lpss_device_desc lpt_dev_desc = {
222 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
223 	.prv_offset = 0x800,
224 };
225 
226 static const struct lpss_device_desc lpt_i2c_dev_desc = {
227 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR,
228 	.prv_offset = 0x800,
229 };
230 
231 static struct property_entry uart_properties[] = {
232 	PROPERTY_ENTRY_U32("reg-io-width", 4),
233 	PROPERTY_ENTRY_U32("reg-shift", 2),
234 	PROPERTY_ENTRY_BOOL("snps,uart-16550-compatible"),
235 	{ },
236 };
237 
238 static const struct lpss_device_desc lpt_uart_dev_desc = {
239 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
240 	.clk_con_id = "baudclk",
241 	.prv_offset = 0x800,
242 	.setup = lpss_uart_setup,
243 	.properties = uart_properties,
244 };
245 
246 static const struct lpss_device_desc lpt_sdio_dev_desc = {
247 	.flags = LPSS_LTR,
248 	.prv_offset = 0x1000,
249 	.prv_size_override = 0x1018,
250 };
251 
252 static const struct lpss_device_desc byt_pwm_dev_desc = {
253 	.flags = LPSS_SAVE_CTX,
254 	.prv_offset = 0x800,
255 	.setup = byt_pwm_setup,
256 };
257 
258 static const struct lpss_device_desc bsw_pwm_dev_desc = {
259 	.flags = LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
260 	.prv_offset = 0x800,
261 	.setup = bsw_pwm_setup,
262 };
263 
264 static const struct lpss_device_desc byt_uart_dev_desc = {
265 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
266 	.clk_con_id = "baudclk",
267 	.prv_offset = 0x800,
268 	.setup = lpss_uart_setup,
269 	.properties = uart_properties,
270 };
271 
272 static const struct lpss_device_desc bsw_uart_dev_desc = {
273 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
274 			| LPSS_NO_D3_DELAY,
275 	.clk_con_id = "baudclk",
276 	.prv_offset = 0x800,
277 	.setup = lpss_uart_setup,
278 	.properties = uart_properties,
279 };
280 
281 static const struct lpss_device_desc byt_spi_dev_desc = {
282 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
283 	.prv_offset = 0x400,
284 };
285 
286 static const struct lpss_device_desc byt_sdio_dev_desc = {
287 	.flags = LPSS_CLK,
288 };
289 
290 static const struct lpss_device_desc byt_i2c_dev_desc = {
291 	.flags = LPSS_CLK | LPSS_SAVE_CTX,
292 	.prv_offset = 0x800,
293 	.setup = byt_i2c_setup,
294 	.resume_from_noirq = true,
295 };
296 
297 static const struct lpss_device_desc bsw_i2c_dev_desc = {
298 	.flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
299 	.prv_offset = 0x800,
300 	.setup = byt_i2c_setup,
301 	.resume_from_noirq = true,
302 };
303 
304 static const struct lpss_device_desc bsw_spi_dev_desc = {
305 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
306 			| LPSS_NO_D3_DELAY,
307 	.prv_offset = 0x400,
308 	.setup = lpss_deassert_reset,
309 };
310 
311 #define ICPU(model)	{ X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, }
312 
313 static const struct x86_cpu_id lpss_cpu_ids[] = {
314 	ICPU(INTEL_FAM6_ATOM_SILVERMONT),	/* Valleyview, Bay Trail */
315 	ICPU(INTEL_FAM6_ATOM_AIRMONT),	/* Braswell, Cherry Trail */
316 	{}
317 };
318 
319 #else
320 
321 #define LPSS_ADDR(desc) (0UL)
322 
323 #endif /* CONFIG_X86_INTEL_LPSS */
324 
325 static const struct acpi_device_id acpi_lpss_device_ids[] = {
326 	/* Generic LPSS devices */
327 	{ "INTL9C60", LPSS_ADDR(lpss_dma_desc) },
328 
329 	/* Lynxpoint LPSS devices */
330 	{ "INT33C0", LPSS_ADDR(lpt_dev_desc) },
331 	{ "INT33C1", LPSS_ADDR(lpt_dev_desc) },
332 	{ "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },
333 	{ "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },
334 	{ "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },
335 	{ "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },
336 	{ "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },
337 	{ "INT33C7", },
338 
339 	/* BayTrail LPSS devices */
340 	{ "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },
341 	{ "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },
342 	{ "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },
343 	{ "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },
344 	{ "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },
345 	{ "INT33B2", },
346 	{ "INT33FC", },
347 
348 	/* Braswell LPSS devices */
349 	{ "80862286", LPSS_ADDR(lpss_dma_desc) },
350 	{ "80862288", LPSS_ADDR(bsw_pwm_dev_desc) },
351 	{ "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },
352 	{ "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },
353 	{ "808622C0", LPSS_ADDR(lpss_dma_desc) },
354 	{ "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) },
355 
356 	/* Broadwell LPSS devices */
357 	{ "INT3430", LPSS_ADDR(lpt_dev_desc) },
358 	{ "INT3431", LPSS_ADDR(lpt_dev_desc) },
359 	{ "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },
360 	{ "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },
361 	{ "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },
362 	{ "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },
363 	{ "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },
364 	{ "INT3437", },
365 
366 	/* Wildcat Point LPSS devices */
367 	{ "INT3438", LPSS_ADDR(lpt_dev_desc) },
368 
369 	{ }
370 };
371 
372 #ifdef CONFIG_X86_INTEL_LPSS
373 
374 static int is_memory(struct acpi_resource *res, void *not_used)
375 {
376 	struct resource r;
377 	return !acpi_dev_resource_memory(res, &r);
378 }
379 
380 /* LPSS main clock device. */
381 static struct platform_device *lpss_clk_dev;
382 
383 static inline void lpt_register_clock_device(void)
384 {
385 	lpss_clk_dev = platform_device_register_simple("clk-lpt", -1, NULL, 0);
386 }
387 
388 static int register_device_clock(struct acpi_device *adev,
389 				 struct lpss_private_data *pdata)
390 {
391 	const struct lpss_device_desc *dev_desc = pdata->dev_desc;
392 	const char *devname = dev_name(&adev->dev);
393 	struct clk *clk;
394 	struct lpss_clk_data *clk_data;
395 	const char *parent, *clk_name;
396 	void __iomem *prv_base;
397 
398 	if (!lpss_clk_dev)
399 		lpt_register_clock_device();
400 
401 	clk_data = platform_get_drvdata(lpss_clk_dev);
402 	if (!clk_data)
403 		return -ENODEV;
404 	clk = clk_data->clk;
405 
406 	if (!pdata->mmio_base
407 	    || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
408 		return -ENODATA;
409 
410 	parent = clk_data->name;
411 	prv_base = pdata->mmio_base + dev_desc->prv_offset;
412 
413 	if (pdata->fixed_clk_rate) {
414 		clk = clk_register_fixed_rate(NULL, devname, parent, 0,
415 					      pdata->fixed_clk_rate);
416 		goto out;
417 	}
418 
419 	if (dev_desc->flags & LPSS_CLK_GATE) {
420 		clk = clk_register_gate(NULL, devname, parent, 0,
421 					prv_base, 0, 0, NULL);
422 		parent = devname;
423 	}
424 
425 	if (dev_desc->flags & LPSS_CLK_DIVIDER) {
426 		/* Prevent division by zero */
427 		if (!readl(prv_base))
428 			writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
429 
430 		clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
431 		if (!clk_name)
432 			return -ENOMEM;
433 		clk = clk_register_fractional_divider(NULL, clk_name, parent,
434 						      0, prv_base,
435 						      1, 15, 16, 15, 0, NULL);
436 		parent = clk_name;
437 
438 		clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
439 		if (!clk_name) {
440 			kfree(parent);
441 			return -ENOMEM;
442 		}
443 		clk = clk_register_gate(NULL, clk_name, parent,
444 					CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
445 					prv_base, 31, 0, NULL);
446 		kfree(parent);
447 		kfree(clk_name);
448 	}
449 out:
450 	if (IS_ERR(clk))
451 		return PTR_ERR(clk);
452 
453 	pdata->clk = clk;
454 	clk_register_clkdev(clk, dev_desc->clk_con_id, devname);
455 	return 0;
456 }
457 
458 struct lpss_device_links {
459 	const char *supplier_hid;
460 	const char *supplier_uid;
461 	const char *consumer_hid;
462 	const char *consumer_uid;
463 	u32 flags;
464 };
465 
466 /*
467  * The _DEP method is used to identify dependencies but instead of creating
468  * device links for every handle in _DEP, only links in the following list are
469  * created. That is necessary because, in the general case, _DEP can refer to
470  * devices that might not have drivers, or that are on different buses, or where
471  * the supplier is not enumerated until after the consumer is probed.
472  */
473 static const struct lpss_device_links lpss_device_links[] = {
474 	{"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME},
475 	{"808622C1", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
476 	{"80860F41", "5", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
477 };
478 
479 static bool hid_uid_match(struct acpi_device *adev,
480 			  const char *hid2, const char *uid2)
481 {
482 	const char *hid1 = acpi_device_hid(adev);
483 	const char *uid1 = acpi_device_uid(adev);
484 
485 	if (strcmp(hid1, hid2))
486 		return false;
487 
488 	if (!uid2)
489 		return true;
490 
491 	return uid1 && !strcmp(uid1, uid2);
492 }
493 
494 static bool acpi_lpss_is_supplier(struct acpi_device *adev,
495 				  const struct lpss_device_links *link)
496 {
497 	return hid_uid_match(adev, link->supplier_hid, link->supplier_uid);
498 }
499 
500 static bool acpi_lpss_is_consumer(struct acpi_device *adev,
501 				  const struct lpss_device_links *link)
502 {
503 	return hid_uid_match(adev, link->consumer_hid, link->consumer_uid);
504 }
505 
506 struct hid_uid {
507 	const char *hid;
508 	const char *uid;
509 };
510 
511 static int match_hid_uid(struct device *dev, const void *data)
512 {
513 	struct acpi_device *adev = ACPI_COMPANION(dev);
514 	const struct hid_uid *id = data;
515 
516 	if (!adev)
517 		return 0;
518 
519 	return hid_uid_match(adev, id->hid, id->uid);
520 }
521 
522 static struct device *acpi_lpss_find_device(const char *hid, const char *uid)
523 {
524 	struct device *dev;
525 
526 	struct hid_uid data = {
527 		.hid = hid,
528 		.uid = uid,
529 	};
530 
531 	dev = bus_find_device(&platform_bus_type, NULL, &data, match_hid_uid);
532 	if (dev)
533 		return dev;
534 
535 	return bus_find_device(&pci_bus_type, NULL, &data, match_hid_uid);
536 }
537 
538 static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle)
539 {
540 	struct acpi_handle_list dep_devices;
541 	acpi_status status;
542 	int i;
543 
544 	if (!acpi_has_method(adev->handle, "_DEP"))
545 		return false;
546 
547 	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
548 					 &dep_devices);
549 	if (ACPI_FAILURE(status)) {
550 		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
551 		return false;
552 	}
553 
554 	for (i = 0; i < dep_devices.count; i++) {
555 		if (dep_devices.handles[i] == handle)
556 			return true;
557 	}
558 
559 	return false;
560 }
561 
562 static void acpi_lpss_link_consumer(struct device *dev1,
563 				    const struct lpss_device_links *link)
564 {
565 	struct device *dev2;
566 
567 	dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid);
568 	if (!dev2)
569 		return;
570 
571 	if (acpi_lpss_dep(ACPI_COMPANION(dev2), ACPI_HANDLE(dev1)))
572 		device_link_add(dev2, dev1, link->flags);
573 
574 	put_device(dev2);
575 }
576 
577 static void acpi_lpss_link_supplier(struct device *dev1,
578 				    const struct lpss_device_links *link)
579 {
580 	struct device *dev2;
581 
582 	dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid);
583 	if (!dev2)
584 		return;
585 
586 	if (acpi_lpss_dep(ACPI_COMPANION(dev1), ACPI_HANDLE(dev2)))
587 		device_link_add(dev1, dev2, link->flags);
588 
589 	put_device(dev2);
590 }
591 
592 static void acpi_lpss_create_device_links(struct acpi_device *adev,
593 					  struct platform_device *pdev)
594 {
595 	int i;
596 
597 	for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) {
598 		const struct lpss_device_links *link = &lpss_device_links[i];
599 
600 		if (acpi_lpss_is_supplier(adev, link))
601 			acpi_lpss_link_consumer(&pdev->dev, link);
602 
603 		if (acpi_lpss_is_consumer(adev, link))
604 			acpi_lpss_link_supplier(&pdev->dev, link);
605 	}
606 }
607 
608 static int acpi_lpss_create_device(struct acpi_device *adev,
609 				   const struct acpi_device_id *id)
610 {
611 	const struct lpss_device_desc *dev_desc;
612 	struct lpss_private_data *pdata;
613 	struct resource_entry *rentry;
614 	struct list_head resource_list;
615 	struct platform_device *pdev;
616 	int ret;
617 
618 	dev_desc = (const struct lpss_device_desc *)id->driver_data;
619 	if (!dev_desc) {
620 		pdev = acpi_create_platform_device(adev, NULL);
621 		return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
622 	}
623 	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
624 	if (!pdata)
625 		return -ENOMEM;
626 
627 	INIT_LIST_HEAD(&resource_list);
628 	ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL);
629 	if (ret < 0)
630 		goto err_out;
631 
632 	list_for_each_entry(rentry, &resource_list, node)
633 		if (resource_type(rentry->res) == IORESOURCE_MEM) {
634 			if (dev_desc->prv_size_override)
635 				pdata->mmio_size = dev_desc->prv_size_override;
636 			else
637 				pdata->mmio_size = resource_size(rentry->res);
638 			pdata->mmio_base = ioremap(rentry->res->start,
639 						   pdata->mmio_size);
640 			break;
641 		}
642 
643 	acpi_dev_free_resource_list(&resource_list);
644 
645 	if (!pdata->mmio_base) {
646 		/* Avoid acpi_bus_attach() instantiating a pdev for this dev. */
647 		adev->pnp.type.platform_id = 0;
648 		/* Skip the device, but continue the namespace scan. */
649 		ret = 0;
650 		goto err_out;
651 	}
652 
653 	pdata->adev = adev;
654 	pdata->dev_desc = dev_desc;
655 
656 	if (dev_desc->setup)
657 		dev_desc->setup(pdata);
658 
659 	if (dev_desc->flags & LPSS_CLK) {
660 		ret = register_device_clock(adev, pdata);
661 		if (ret) {
662 			/* Skip the device, but continue the namespace scan. */
663 			ret = 0;
664 			goto err_out;
665 		}
666 	}
667 
668 	/*
669 	 * This works around a known issue in ACPI tables where LPSS devices
670 	 * have _PS0 and _PS3 without _PSC (and no power resources), so
671 	 * acpi_bus_init_power() will assume that the BIOS has put them into D0.
672 	 */
673 	acpi_device_fix_up_power(adev);
674 
675 	adev->driver_data = pdata;
676 	pdev = acpi_create_platform_device(adev, dev_desc->properties);
677 	if (!IS_ERR_OR_NULL(pdev)) {
678 		acpi_lpss_create_device_links(adev, pdev);
679 		return 1;
680 	}
681 
682 	ret = PTR_ERR(pdev);
683 	adev->driver_data = NULL;
684 
685  err_out:
686 	kfree(pdata);
687 	return ret;
688 }
689 
690 static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
691 {
692 	return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
693 }
694 
695 static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
696 			     unsigned int reg)
697 {
698 	writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
699 }
700 
701 static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
702 {
703 	struct acpi_device *adev;
704 	struct lpss_private_data *pdata;
705 	unsigned long flags;
706 	int ret;
707 
708 	ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev);
709 	if (WARN_ON(ret))
710 		return ret;
711 
712 	spin_lock_irqsave(&dev->power.lock, flags);
713 	if (pm_runtime_suspended(dev)) {
714 		ret = -EAGAIN;
715 		goto out;
716 	}
717 	pdata = acpi_driver_data(adev);
718 	if (WARN_ON(!pdata || !pdata->mmio_base)) {
719 		ret = -ENODEV;
720 		goto out;
721 	}
722 	*val = __lpss_reg_read(pdata, reg);
723 
724  out:
725 	spin_unlock_irqrestore(&dev->power.lock, flags);
726 	return ret;
727 }
728 
729 static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
730 			     char *buf)
731 {
732 	u32 ltr_value = 0;
733 	unsigned int reg;
734 	int ret;
735 
736 	reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
737 	ret = lpss_reg_read(dev, reg, &ltr_value);
738 	if (ret)
739 		return ret;
740 
741 	return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value);
742 }
743 
744 static ssize_t lpss_ltr_mode_show(struct device *dev,
745 				  struct device_attribute *attr, char *buf)
746 {
747 	u32 ltr_mode = 0;
748 	char *outstr;
749 	int ret;
750 
751 	ret = lpss_reg_read(dev, LPSS_GENERAL, &ltr_mode);
752 	if (ret)
753 		return ret;
754 
755 	outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
756 	return sprintf(buf, "%s\n", outstr);
757 }
758 
759 static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
760 static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
761 static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
762 
763 static struct attribute *lpss_attrs[] = {
764 	&dev_attr_auto_ltr.attr,
765 	&dev_attr_sw_ltr.attr,
766 	&dev_attr_ltr_mode.attr,
767 	NULL,
768 };
769 
770 static const struct attribute_group lpss_attr_group = {
771 	.attrs = lpss_attrs,
772 	.name = "lpss_ltr",
773 };
774 
775 static void acpi_lpss_set_ltr(struct device *dev, s32 val)
776 {
777 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
778 	u32 ltr_mode, ltr_val;
779 
780 	ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
781 	if (val < 0) {
782 		if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
783 			ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
784 			__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
785 		}
786 		return;
787 	}
788 	ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
789 	if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
790 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
791 		val = LPSS_LTR_MAX_VAL;
792 	} else if (val > LPSS_LTR_MAX_VAL) {
793 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
794 		val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
795 	} else {
796 		ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
797 	}
798 	ltr_val |= val;
799 	__lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
800 	if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
801 		ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
802 		__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
803 	}
804 }
805 
806 #ifdef CONFIG_PM
807 /**
808  * acpi_lpss_save_ctx() - Save the private registers of LPSS device
809  * @dev: LPSS device
810  * @pdata: pointer to the private data of the LPSS device
811  *
812  * Most LPSS devices have private registers which may loose their context when
813  * the device is powered down. acpi_lpss_save_ctx() saves those registers into
814  * prv_reg_ctx array.
815  */
816 static void acpi_lpss_save_ctx(struct device *dev,
817 			       struct lpss_private_data *pdata)
818 {
819 	unsigned int i;
820 
821 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
822 		unsigned long offset = i * sizeof(u32);
823 
824 		pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
825 		dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
826 			pdata->prv_reg_ctx[i], offset);
827 	}
828 }
829 
830 /**
831  * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
832  * @dev: LPSS device
833  * @pdata: pointer to the private data of the LPSS device
834  *
835  * Restores the registers that were previously stored with acpi_lpss_save_ctx().
836  */
837 static void acpi_lpss_restore_ctx(struct device *dev,
838 				  struct lpss_private_data *pdata)
839 {
840 	unsigned int i;
841 
842 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
843 		unsigned long offset = i * sizeof(u32);
844 
845 		__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
846 		dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
847 			pdata->prv_reg_ctx[i], offset);
848 	}
849 }
850 
851 static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
852 {
853 	/*
854 	 * The following delay is needed or the subsequent write operations may
855 	 * fail. The LPSS devices are actually PCI devices and the PCI spec
856 	 * expects 10ms delay before the device can be accessed after D3 to D0
857 	 * transition. However some platforms like BSW does not need this delay.
858 	 */
859 	unsigned int delay = 10;	/* default 10ms delay */
860 
861 	if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)
862 		delay = 0;
863 
864 	msleep(delay);
865 }
866 
867 static int acpi_lpss_activate(struct device *dev)
868 {
869 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
870 	int ret;
871 
872 	ret = acpi_dev_resume(dev);
873 	if (ret)
874 		return ret;
875 
876 	acpi_lpss_d3_to_d0_delay(pdata);
877 
878 	/*
879 	 * This is called only on ->probe() stage where a device is either in
880 	 * known state defined by BIOS or most likely powered off. Due to this
881 	 * we have to deassert reset line to be sure that ->probe() will
882 	 * recognize the device.
883 	 */
884 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
885 		lpss_deassert_reset(pdata);
886 
887 	return 0;
888 }
889 
890 static void acpi_lpss_dismiss(struct device *dev)
891 {
892 	acpi_dev_suspend(dev, false);
893 }
894 
895 /* IOSF SB for LPSS island */
896 #define LPSS_IOSF_UNIT_LPIOEP		0xA0
897 #define LPSS_IOSF_UNIT_LPIO1		0xAB
898 #define LPSS_IOSF_UNIT_LPIO2		0xAC
899 
900 #define LPSS_IOSF_PMCSR			0x84
901 #define LPSS_PMCSR_D0			0
902 #define LPSS_PMCSR_D3hot		3
903 #define LPSS_PMCSR_Dx_MASK		GENMASK(1, 0)
904 
905 #define LPSS_IOSF_GPIODEF0		0x154
906 #define LPSS_GPIODEF0_DMA1_D3		BIT(2)
907 #define LPSS_GPIODEF0_DMA2_D3		BIT(3)
908 #define LPSS_GPIODEF0_DMA_D3_MASK	GENMASK(3, 2)
909 #define LPSS_GPIODEF0_DMA_LLP		BIT(13)
910 
911 static DEFINE_MUTEX(lpss_iosf_mutex);
912 static bool lpss_iosf_d3_entered = true;
913 
914 static void lpss_iosf_enter_d3_state(void)
915 {
916 	u32 value1 = 0;
917 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
918 	u32 value2 = LPSS_PMCSR_D3hot;
919 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
920 	/*
921 	 * PMC provides an information about actual status of the LPSS devices.
922 	 * Here we read the values related to LPSS power island, i.e. LPSS
923 	 * devices, excluding both LPSS DMA controllers, along with SCC domain.
924 	 */
925 	u32 func_dis, d3_sts_0, pmc_status;
926 	int ret;
927 
928 	ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);
929 	if (ret)
930 		return;
931 
932 	mutex_lock(&lpss_iosf_mutex);
933 
934 	ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);
935 	if (ret)
936 		goto exit;
937 
938 	/*
939 	 * Get the status of entire LPSS power island per device basis.
940 	 * Shutdown both LPSS DMA controllers if and only if all other devices
941 	 * are already in D3hot.
942 	 */
943 	pmc_status = (~(d3_sts_0 | func_dis)) & pmc_atom_d3_mask;
944 	if (pmc_status)
945 		goto exit;
946 
947 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
948 			LPSS_IOSF_PMCSR, value2, mask2);
949 
950 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
951 			LPSS_IOSF_PMCSR, value2, mask2);
952 
953 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
954 			LPSS_IOSF_GPIODEF0, value1, mask1);
955 
956 	lpss_iosf_d3_entered = true;
957 
958 exit:
959 	mutex_unlock(&lpss_iosf_mutex);
960 }
961 
962 static void lpss_iosf_exit_d3_state(void)
963 {
964 	u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 |
965 		     LPSS_GPIODEF0_DMA_LLP;
966 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
967 	u32 value2 = LPSS_PMCSR_D0;
968 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
969 
970 	mutex_lock(&lpss_iosf_mutex);
971 
972 	if (!lpss_iosf_d3_entered)
973 		goto exit;
974 
975 	lpss_iosf_d3_entered = false;
976 
977 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
978 			LPSS_IOSF_GPIODEF0, value1, mask1);
979 
980 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
981 			LPSS_IOSF_PMCSR, value2, mask2);
982 
983 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
984 			LPSS_IOSF_PMCSR, value2, mask2);
985 
986 exit:
987 	mutex_unlock(&lpss_iosf_mutex);
988 }
989 
990 static int acpi_lpss_suspend(struct device *dev, bool wakeup)
991 {
992 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
993 	int ret;
994 
995 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
996 		acpi_lpss_save_ctx(dev, pdata);
997 
998 	ret = acpi_dev_suspend(dev, wakeup);
999 
1000 	/*
1001 	 * This call must be last in the sequence, otherwise PMC will return
1002 	 * wrong status for devices being about to be powered off. See
1003 	 * lpss_iosf_enter_d3_state() for further information.
1004 	 */
1005 	if (acpi_target_system_state() == ACPI_STATE_S0 &&
1006 	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1007 		lpss_iosf_enter_d3_state();
1008 
1009 	return ret;
1010 }
1011 
1012 static int acpi_lpss_resume(struct device *dev)
1013 {
1014 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1015 	int ret;
1016 
1017 	/*
1018 	 * This call is kept first to be in symmetry with
1019 	 * acpi_lpss_runtime_suspend() one.
1020 	 */
1021 	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1022 		lpss_iosf_exit_d3_state();
1023 
1024 	ret = acpi_dev_resume(dev);
1025 	if (ret)
1026 		return ret;
1027 
1028 	acpi_lpss_d3_to_d0_delay(pdata);
1029 
1030 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
1031 		acpi_lpss_restore_ctx(dev, pdata);
1032 
1033 	return 0;
1034 }
1035 
1036 #ifdef CONFIG_PM_SLEEP
1037 static int acpi_lpss_do_suspend_late(struct device *dev)
1038 {
1039 	int ret;
1040 
1041 	if (dev_pm_smart_suspend_and_suspended(dev))
1042 		return 0;
1043 
1044 	ret = pm_generic_suspend_late(dev);
1045 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1046 }
1047 
1048 static int acpi_lpss_suspend_late(struct device *dev)
1049 {
1050 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1051 
1052 	if (pdata->dev_desc->resume_from_noirq)
1053 		return 0;
1054 
1055 	return acpi_lpss_do_suspend_late(dev);
1056 }
1057 
1058 static int acpi_lpss_suspend_noirq(struct device *dev)
1059 {
1060 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1061 	int ret;
1062 
1063 	if (pdata->dev_desc->resume_from_noirq) {
1064 		/*
1065 		 * The driver's ->suspend_late callback will be invoked by
1066 		 * acpi_lpss_do_suspend_late(), with the assumption that the
1067 		 * driver really wanted to run that code in ->suspend_noirq, but
1068 		 * it could not run after acpi_dev_suspend() and the driver
1069 		 * expected the latter to be called in the "late" phase.
1070 		 */
1071 		ret = acpi_lpss_do_suspend_late(dev);
1072 		if (ret)
1073 			return ret;
1074 	}
1075 
1076 	return acpi_subsys_suspend_noirq(dev);
1077 }
1078 
1079 static int acpi_lpss_do_resume_early(struct device *dev)
1080 {
1081 	int ret = acpi_lpss_resume(dev);
1082 
1083 	return ret ? ret : pm_generic_resume_early(dev);
1084 }
1085 
1086 static int acpi_lpss_resume_early(struct device *dev)
1087 {
1088 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1089 
1090 	if (pdata->dev_desc->resume_from_noirq)
1091 		return 0;
1092 
1093 	return acpi_lpss_do_resume_early(dev);
1094 }
1095 
1096 static int acpi_lpss_resume_noirq(struct device *dev)
1097 {
1098 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1099 	int ret;
1100 
1101 	/* Follow acpi_subsys_resume_noirq(). */
1102 	if (dev_pm_may_skip_resume(dev))
1103 		return 0;
1104 
1105 	if (dev_pm_smart_suspend_and_suspended(dev))
1106 		pm_runtime_set_active(dev);
1107 
1108 	ret = pm_generic_resume_noirq(dev);
1109 	if (ret)
1110 		return ret;
1111 
1112 	if (!pdata->dev_desc->resume_from_noirq)
1113 		return 0;
1114 
1115 	/*
1116 	 * The driver's ->resume_early callback will be invoked by
1117 	 * acpi_lpss_do_resume_early(), with the assumption that the driver
1118 	 * really wanted to run that code in ->resume_noirq, but it could not
1119 	 * run before acpi_dev_resume() and the driver expected the latter to be
1120 	 * called in the "early" phase.
1121 	 */
1122 	return acpi_lpss_do_resume_early(dev);
1123 }
1124 
1125 static int acpi_lpss_do_restore_early(struct device *dev)
1126 {
1127 	int ret = acpi_lpss_resume(dev);
1128 
1129 	return ret ? ret : pm_generic_restore_early(dev);
1130 }
1131 
1132 static int acpi_lpss_restore_early(struct device *dev)
1133 {
1134 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1135 
1136 	if (pdata->dev_desc->resume_from_noirq)
1137 		return 0;
1138 
1139 	return acpi_lpss_do_restore_early(dev);
1140 }
1141 
1142 static int acpi_lpss_restore_noirq(struct device *dev)
1143 {
1144 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1145 	int ret;
1146 
1147 	ret = pm_generic_restore_noirq(dev);
1148 	if (ret)
1149 		return ret;
1150 
1151 	if (!pdata->dev_desc->resume_from_noirq)
1152 		return 0;
1153 
1154 	/* This is analogous to what happens in acpi_lpss_resume_noirq(). */
1155 	return acpi_lpss_do_restore_early(dev);
1156 }
1157 
1158 static int acpi_lpss_do_poweroff_late(struct device *dev)
1159 {
1160 	int ret = pm_generic_poweroff_late(dev);
1161 
1162 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1163 }
1164 
1165 static int acpi_lpss_poweroff_late(struct device *dev)
1166 {
1167 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1168 
1169 	if (dev_pm_smart_suspend_and_suspended(dev))
1170 		return 0;
1171 
1172 	if (pdata->dev_desc->resume_from_noirq)
1173 		return 0;
1174 
1175 	return acpi_lpss_do_poweroff_late(dev);
1176 }
1177 
1178 static int acpi_lpss_poweroff_noirq(struct device *dev)
1179 {
1180 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1181 
1182 	if (dev_pm_smart_suspend_and_suspended(dev))
1183 		return 0;
1184 
1185 	if (pdata->dev_desc->resume_from_noirq) {
1186 		/* This is analogous to the acpi_lpss_suspend_noirq() case. */
1187 		int ret = acpi_lpss_do_poweroff_late(dev);
1188 		if (ret)
1189 			return ret;
1190 	}
1191 
1192 	return pm_generic_poweroff_noirq(dev);
1193 }
1194 #endif /* CONFIG_PM_SLEEP */
1195 
1196 static int acpi_lpss_runtime_suspend(struct device *dev)
1197 {
1198 	int ret = pm_generic_runtime_suspend(dev);
1199 
1200 	return ret ? ret : acpi_lpss_suspend(dev, true);
1201 }
1202 
1203 static int acpi_lpss_runtime_resume(struct device *dev)
1204 {
1205 	int ret = acpi_lpss_resume(dev);
1206 
1207 	return ret ? ret : pm_generic_runtime_resume(dev);
1208 }
1209 #endif /* CONFIG_PM */
1210 
1211 static struct dev_pm_domain acpi_lpss_pm_domain = {
1212 #ifdef CONFIG_PM
1213 	.activate = acpi_lpss_activate,
1214 	.dismiss = acpi_lpss_dismiss,
1215 #endif
1216 	.ops = {
1217 #ifdef CONFIG_PM
1218 #ifdef CONFIG_PM_SLEEP
1219 		.prepare = acpi_subsys_prepare,
1220 		.complete = acpi_subsys_complete,
1221 		.suspend = acpi_subsys_suspend,
1222 		.suspend_late = acpi_lpss_suspend_late,
1223 		.suspend_noirq = acpi_lpss_suspend_noirq,
1224 		.resume_noirq = acpi_lpss_resume_noirq,
1225 		.resume_early = acpi_lpss_resume_early,
1226 		.freeze = acpi_subsys_freeze,
1227 		.poweroff = acpi_subsys_poweroff,
1228 		.poweroff_late = acpi_lpss_poweroff_late,
1229 		.poweroff_noirq = acpi_lpss_poweroff_noirq,
1230 		.restore_noirq = acpi_lpss_restore_noirq,
1231 		.restore_early = acpi_lpss_restore_early,
1232 #endif
1233 		.runtime_suspend = acpi_lpss_runtime_suspend,
1234 		.runtime_resume = acpi_lpss_runtime_resume,
1235 #endif
1236 	},
1237 };
1238 
1239 static int acpi_lpss_platform_notify(struct notifier_block *nb,
1240 				     unsigned long action, void *data)
1241 {
1242 	struct platform_device *pdev = to_platform_device(data);
1243 	struct lpss_private_data *pdata;
1244 	struct acpi_device *adev;
1245 	const struct acpi_device_id *id;
1246 
1247 	id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
1248 	if (!id || !id->driver_data)
1249 		return 0;
1250 
1251 	if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
1252 		return 0;
1253 
1254 	pdata = acpi_driver_data(adev);
1255 	if (!pdata)
1256 		return 0;
1257 
1258 	if (pdata->mmio_base &&
1259 	    pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
1260 		dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
1261 		return 0;
1262 	}
1263 
1264 	switch (action) {
1265 	case BUS_NOTIFY_BIND_DRIVER:
1266 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1267 		break;
1268 	case BUS_NOTIFY_DRIVER_NOT_BOUND:
1269 	case BUS_NOTIFY_UNBOUND_DRIVER:
1270 		dev_pm_domain_set(&pdev->dev, NULL);
1271 		break;
1272 	case BUS_NOTIFY_ADD_DEVICE:
1273 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1274 		if (pdata->dev_desc->flags & LPSS_LTR)
1275 			return sysfs_create_group(&pdev->dev.kobj,
1276 						  &lpss_attr_group);
1277 		break;
1278 	case BUS_NOTIFY_DEL_DEVICE:
1279 		if (pdata->dev_desc->flags & LPSS_LTR)
1280 			sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
1281 		dev_pm_domain_set(&pdev->dev, NULL);
1282 		break;
1283 	default:
1284 		break;
1285 	}
1286 
1287 	return 0;
1288 }
1289 
1290 static struct notifier_block acpi_lpss_nb = {
1291 	.notifier_call = acpi_lpss_platform_notify,
1292 };
1293 
1294 static void acpi_lpss_bind(struct device *dev)
1295 {
1296 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1297 
1298 	if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
1299 		return;
1300 
1301 	if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
1302 		dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
1303 	else
1304 		dev_err(dev, "MMIO size insufficient to access LTR\n");
1305 }
1306 
1307 static void acpi_lpss_unbind(struct device *dev)
1308 {
1309 	dev->power.set_latency_tolerance = NULL;
1310 }
1311 
1312 static struct acpi_scan_handler lpss_handler = {
1313 	.ids = acpi_lpss_device_ids,
1314 	.attach = acpi_lpss_create_device,
1315 	.bind = acpi_lpss_bind,
1316 	.unbind = acpi_lpss_unbind,
1317 };
1318 
1319 void __init acpi_lpss_init(void)
1320 {
1321 	const struct x86_cpu_id *id;
1322 	int ret;
1323 
1324 	ret = lpt_clk_init();
1325 	if (ret)
1326 		return;
1327 
1328 	id = x86_match_cpu(lpss_cpu_ids);
1329 	if (id)
1330 		lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;
1331 
1332 	bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
1333 	acpi_scan_add_handler(&lpss_handler);
1334 }
1335 
1336 #else
1337 
1338 static struct acpi_scan_handler lpss_handler = {
1339 	.ids = acpi_lpss_device_ids,
1340 };
1341 
1342 void __init acpi_lpss_init(void)
1343 {
1344 	acpi_scan_add_handler(&lpss_handler);
1345 }
1346 
1347 #endif /* CONFIG_X86_INTEL_LPSS */
1348