xref: /openbmc/linux/drivers/acpi/acpi_lpss.c (revision 2022ca0a)
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 			| LPSS_SAVE_CTX,
224 	.prv_offset = 0x800,
225 };
226 
227 static const struct lpss_device_desc lpt_i2c_dev_desc = {
228 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR | LPSS_SAVE_CTX,
229 	.prv_offset = 0x800,
230 };
231 
232 static struct property_entry uart_properties[] = {
233 	PROPERTY_ENTRY_U32("reg-io-width", 4),
234 	PROPERTY_ENTRY_U32("reg-shift", 2),
235 	PROPERTY_ENTRY_BOOL("snps,uart-16550-compatible"),
236 	{ },
237 };
238 
239 static const struct lpss_device_desc lpt_uart_dev_desc = {
240 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR
241 			| LPSS_SAVE_CTX,
242 	.clk_con_id = "baudclk",
243 	.prv_offset = 0x800,
244 	.setup = lpss_uart_setup,
245 	.properties = uart_properties,
246 };
247 
248 static const struct lpss_device_desc lpt_sdio_dev_desc = {
249 	.flags = LPSS_LTR,
250 	.prv_offset = 0x1000,
251 	.prv_size_override = 0x1018,
252 };
253 
254 static const struct lpss_device_desc byt_pwm_dev_desc = {
255 	.flags = LPSS_SAVE_CTX,
256 	.prv_offset = 0x800,
257 	.setup = byt_pwm_setup,
258 };
259 
260 static const struct lpss_device_desc bsw_pwm_dev_desc = {
261 	.flags = LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
262 	.prv_offset = 0x800,
263 	.setup = bsw_pwm_setup,
264 };
265 
266 static const struct lpss_device_desc byt_uart_dev_desc = {
267 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
268 	.clk_con_id = "baudclk",
269 	.prv_offset = 0x800,
270 	.setup = lpss_uart_setup,
271 	.properties = uart_properties,
272 };
273 
274 static const struct lpss_device_desc bsw_uart_dev_desc = {
275 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
276 			| LPSS_NO_D3_DELAY,
277 	.clk_con_id = "baudclk",
278 	.prv_offset = 0x800,
279 	.setup = lpss_uart_setup,
280 	.properties = uart_properties,
281 };
282 
283 static const struct lpss_device_desc byt_spi_dev_desc = {
284 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
285 	.prv_offset = 0x400,
286 };
287 
288 static const struct lpss_device_desc byt_sdio_dev_desc = {
289 	.flags = LPSS_CLK,
290 };
291 
292 static const struct lpss_device_desc byt_i2c_dev_desc = {
293 	.flags = LPSS_CLK | LPSS_SAVE_CTX,
294 	.prv_offset = 0x800,
295 	.setup = byt_i2c_setup,
296 	.resume_from_noirq = true,
297 };
298 
299 static const struct lpss_device_desc bsw_i2c_dev_desc = {
300 	.flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
301 	.prv_offset = 0x800,
302 	.setup = byt_i2c_setup,
303 	.resume_from_noirq = true,
304 };
305 
306 static const struct lpss_device_desc bsw_spi_dev_desc = {
307 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
308 			| LPSS_NO_D3_DELAY,
309 	.prv_offset = 0x400,
310 	.setup = lpss_deassert_reset,
311 };
312 
313 #define ICPU(model)	{ X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, }
314 
315 static const struct x86_cpu_id lpss_cpu_ids[] = {
316 	ICPU(INTEL_FAM6_ATOM_SILVERMONT),	/* Valleyview, Bay Trail */
317 	ICPU(INTEL_FAM6_ATOM_AIRMONT),	/* Braswell, Cherry Trail */
318 	{}
319 };
320 
321 #else
322 
323 #define LPSS_ADDR(desc) (0UL)
324 
325 #endif /* CONFIG_X86_INTEL_LPSS */
326 
327 static const struct acpi_device_id acpi_lpss_device_ids[] = {
328 	/* Generic LPSS devices */
329 	{ "INTL9C60", LPSS_ADDR(lpss_dma_desc) },
330 
331 	/* Lynxpoint LPSS devices */
332 	{ "INT33C0", LPSS_ADDR(lpt_dev_desc) },
333 	{ "INT33C1", LPSS_ADDR(lpt_dev_desc) },
334 	{ "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },
335 	{ "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },
336 	{ "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },
337 	{ "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },
338 	{ "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },
339 	{ "INT33C7", },
340 
341 	/* BayTrail LPSS devices */
342 	{ "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },
343 	{ "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },
344 	{ "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },
345 	{ "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },
346 	{ "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },
347 	{ "INT33B2", },
348 	{ "INT33FC", },
349 
350 	/* Braswell LPSS devices */
351 	{ "80862286", LPSS_ADDR(lpss_dma_desc) },
352 	{ "80862288", LPSS_ADDR(bsw_pwm_dev_desc) },
353 	{ "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },
354 	{ "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },
355 	{ "808622C0", LPSS_ADDR(lpss_dma_desc) },
356 	{ "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) },
357 
358 	/* Broadwell LPSS devices */
359 	{ "INT3430", LPSS_ADDR(lpt_dev_desc) },
360 	{ "INT3431", LPSS_ADDR(lpt_dev_desc) },
361 	{ "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },
362 	{ "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },
363 	{ "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },
364 	{ "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },
365 	{ "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },
366 	{ "INT3437", },
367 
368 	/* Wildcat Point LPSS devices */
369 	{ "INT3438", LPSS_ADDR(lpt_dev_desc) },
370 
371 	{ }
372 };
373 
374 #ifdef CONFIG_X86_INTEL_LPSS
375 
376 static int is_memory(struct acpi_resource *res, void *not_used)
377 {
378 	struct resource r;
379 	return !acpi_dev_resource_memory(res, &r);
380 }
381 
382 /* LPSS main clock device. */
383 static struct platform_device *lpss_clk_dev;
384 
385 static inline void lpt_register_clock_device(void)
386 {
387 	lpss_clk_dev = platform_device_register_simple("clk-lpt", -1, NULL, 0);
388 }
389 
390 static int register_device_clock(struct acpi_device *adev,
391 				 struct lpss_private_data *pdata)
392 {
393 	const struct lpss_device_desc *dev_desc = pdata->dev_desc;
394 	const char *devname = dev_name(&adev->dev);
395 	struct clk *clk;
396 	struct lpss_clk_data *clk_data;
397 	const char *parent, *clk_name;
398 	void __iomem *prv_base;
399 
400 	if (!lpss_clk_dev)
401 		lpt_register_clock_device();
402 
403 	clk_data = platform_get_drvdata(lpss_clk_dev);
404 	if (!clk_data)
405 		return -ENODEV;
406 	clk = clk_data->clk;
407 
408 	if (!pdata->mmio_base
409 	    || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
410 		return -ENODATA;
411 
412 	parent = clk_data->name;
413 	prv_base = pdata->mmio_base + dev_desc->prv_offset;
414 
415 	if (pdata->fixed_clk_rate) {
416 		clk = clk_register_fixed_rate(NULL, devname, parent, 0,
417 					      pdata->fixed_clk_rate);
418 		goto out;
419 	}
420 
421 	if (dev_desc->flags & LPSS_CLK_GATE) {
422 		clk = clk_register_gate(NULL, devname, parent, 0,
423 					prv_base, 0, 0, NULL);
424 		parent = devname;
425 	}
426 
427 	if (dev_desc->flags & LPSS_CLK_DIVIDER) {
428 		/* Prevent division by zero */
429 		if (!readl(prv_base))
430 			writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
431 
432 		clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
433 		if (!clk_name)
434 			return -ENOMEM;
435 		clk = clk_register_fractional_divider(NULL, clk_name, parent,
436 						      0, prv_base,
437 						      1, 15, 16, 15, 0, NULL);
438 		parent = clk_name;
439 
440 		clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
441 		if (!clk_name) {
442 			kfree(parent);
443 			return -ENOMEM;
444 		}
445 		clk = clk_register_gate(NULL, clk_name, parent,
446 					CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
447 					prv_base, 31, 0, NULL);
448 		kfree(parent);
449 		kfree(clk_name);
450 	}
451 out:
452 	if (IS_ERR(clk))
453 		return PTR_ERR(clk);
454 
455 	pdata->clk = clk;
456 	clk_register_clkdev(clk, dev_desc->clk_con_id, devname);
457 	return 0;
458 }
459 
460 struct lpss_device_links {
461 	const char *supplier_hid;
462 	const char *supplier_uid;
463 	const char *consumer_hid;
464 	const char *consumer_uid;
465 	u32 flags;
466 };
467 
468 /*
469  * The _DEP method is used to identify dependencies but instead of creating
470  * device links for every handle in _DEP, only links in the following list are
471  * created. That is necessary because, in the general case, _DEP can refer to
472  * devices that might not have drivers, or that are on different buses, or where
473  * the supplier is not enumerated until after the consumer is probed.
474  */
475 static const struct lpss_device_links lpss_device_links[] = {
476 	{"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME},
477 	{"808622C1", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
478 	{"80860F41", "5", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
479 };
480 
481 static bool hid_uid_match(struct acpi_device *adev,
482 			  const char *hid2, const char *uid2)
483 {
484 	const char *hid1 = acpi_device_hid(adev);
485 	const char *uid1 = acpi_device_uid(adev);
486 
487 	if (strcmp(hid1, hid2))
488 		return false;
489 
490 	if (!uid2)
491 		return true;
492 
493 	return uid1 && !strcmp(uid1, uid2);
494 }
495 
496 static bool acpi_lpss_is_supplier(struct acpi_device *adev,
497 				  const struct lpss_device_links *link)
498 {
499 	return hid_uid_match(adev, link->supplier_hid, link->supplier_uid);
500 }
501 
502 static bool acpi_lpss_is_consumer(struct acpi_device *adev,
503 				  const struct lpss_device_links *link)
504 {
505 	return hid_uid_match(adev, link->consumer_hid, link->consumer_uid);
506 }
507 
508 struct hid_uid {
509 	const char *hid;
510 	const char *uid;
511 };
512 
513 static int match_hid_uid(struct device *dev, const void *data)
514 {
515 	struct acpi_device *adev = ACPI_COMPANION(dev);
516 	const struct hid_uid *id = data;
517 
518 	if (!adev)
519 		return 0;
520 
521 	return hid_uid_match(adev, id->hid, id->uid);
522 }
523 
524 static struct device *acpi_lpss_find_device(const char *hid, const char *uid)
525 {
526 	struct device *dev;
527 
528 	struct hid_uid data = {
529 		.hid = hid,
530 		.uid = uid,
531 	};
532 
533 	dev = bus_find_device(&platform_bus_type, NULL, &data, match_hid_uid);
534 	if (dev)
535 		return dev;
536 
537 	return bus_find_device(&pci_bus_type, NULL, &data, match_hid_uid);
538 }
539 
540 static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle)
541 {
542 	struct acpi_handle_list dep_devices;
543 	acpi_status status;
544 	int i;
545 
546 	if (!acpi_has_method(adev->handle, "_DEP"))
547 		return false;
548 
549 	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
550 					 &dep_devices);
551 	if (ACPI_FAILURE(status)) {
552 		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
553 		return false;
554 	}
555 
556 	for (i = 0; i < dep_devices.count; i++) {
557 		if (dep_devices.handles[i] == handle)
558 			return true;
559 	}
560 
561 	return false;
562 }
563 
564 static void acpi_lpss_link_consumer(struct device *dev1,
565 				    const struct lpss_device_links *link)
566 {
567 	struct device *dev2;
568 
569 	dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid);
570 	if (!dev2)
571 		return;
572 
573 	if (acpi_lpss_dep(ACPI_COMPANION(dev2), ACPI_HANDLE(dev1)))
574 		device_link_add(dev2, dev1, link->flags);
575 
576 	put_device(dev2);
577 }
578 
579 static void acpi_lpss_link_supplier(struct device *dev1,
580 				    const struct lpss_device_links *link)
581 {
582 	struct device *dev2;
583 
584 	dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid);
585 	if (!dev2)
586 		return;
587 
588 	if (acpi_lpss_dep(ACPI_COMPANION(dev1), ACPI_HANDLE(dev2)))
589 		device_link_add(dev1, dev2, link->flags);
590 
591 	put_device(dev2);
592 }
593 
594 static void acpi_lpss_create_device_links(struct acpi_device *adev,
595 					  struct platform_device *pdev)
596 {
597 	int i;
598 
599 	for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) {
600 		const struct lpss_device_links *link = &lpss_device_links[i];
601 
602 		if (acpi_lpss_is_supplier(adev, link))
603 			acpi_lpss_link_consumer(&pdev->dev, link);
604 
605 		if (acpi_lpss_is_consumer(adev, link))
606 			acpi_lpss_link_supplier(&pdev->dev, link);
607 	}
608 }
609 
610 static int acpi_lpss_create_device(struct acpi_device *adev,
611 				   const struct acpi_device_id *id)
612 {
613 	const struct lpss_device_desc *dev_desc;
614 	struct lpss_private_data *pdata;
615 	struct resource_entry *rentry;
616 	struct list_head resource_list;
617 	struct platform_device *pdev;
618 	int ret;
619 
620 	dev_desc = (const struct lpss_device_desc *)id->driver_data;
621 	if (!dev_desc) {
622 		pdev = acpi_create_platform_device(adev, NULL);
623 		return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
624 	}
625 	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
626 	if (!pdata)
627 		return -ENOMEM;
628 
629 	INIT_LIST_HEAD(&resource_list);
630 	ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL);
631 	if (ret < 0)
632 		goto err_out;
633 
634 	list_for_each_entry(rentry, &resource_list, node)
635 		if (resource_type(rentry->res) == IORESOURCE_MEM) {
636 			if (dev_desc->prv_size_override)
637 				pdata->mmio_size = dev_desc->prv_size_override;
638 			else
639 				pdata->mmio_size = resource_size(rentry->res);
640 			pdata->mmio_base = ioremap(rentry->res->start,
641 						   pdata->mmio_size);
642 			break;
643 		}
644 
645 	acpi_dev_free_resource_list(&resource_list);
646 
647 	if (!pdata->mmio_base) {
648 		/* Avoid acpi_bus_attach() instantiating a pdev for this dev. */
649 		adev->pnp.type.platform_id = 0;
650 		/* Skip the device, but continue the namespace scan. */
651 		ret = 0;
652 		goto err_out;
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 			/* Skip the device, but continue the namespace scan. */
665 			ret = 0;
666 			goto err_out;
667 		}
668 	}
669 
670 	/*
671 	 * This works around a known issue in ACPI tables where LPSS devices
672 	 * have _PS0 and _PS3 without _PSC (and no power resources), so
673 	 * acpi_bus_init_power() will assume that the BIOS has put them into D0.
674 	 */
675 	acpi_device_fix_up_power(adev);
676 
677 	adev->driver_data = pdata;
678 	pdev = acpi_create_platform_device(adev, dev_desc->properties);
679 	if (!IS_ERR_OR_NULL(pdev)) {
680 		acpi_lpss_create_device_links(adev, pdev);
681 		return 1;
682 	}
683 
684 	ret = PTR_ERR(pdev);
685 	adev->driver_data = NULL;
686 
687  err_out:
688 	kfree(pdata);
689 	return ret;
690 }
691 
692 static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
693 {
694 	return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
695 }
696 
697 static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
698 			     unsigned int reg)
699 {
700 	writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
701 }
702 
703 static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
704 {
705 	struct acpi_device *adev;
706 	struct lpss_private_data *pdata;
707 	unsigned long flags;
708 	int ret;
709 
710 	ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev);
711 	if (WARN_ON(ret))
712 		return ret;
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 
726  out:
727 	spin_unlock_irqrestore(&dev->power.lock, flags);
728 	return ret;
729 }
730 
731 static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
732 			     char *buf)
733 {
734 	u32 ltr_value = 0;
735 	unsigned int reg;
736 	int ret;
737 
738 	reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
739 	ret = lpss_reg_read(dev, reg, &ltr_value);
740 	if (ret)
741 		return ret;
742 
743 	return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value);
744 }
745 
746 static ssize_t lpss_ltr_mode_show(struct device *dev,
747 				  struct device_attribute *attr, char *buf)
748 {
749 	u32 ltr_mode = 0;
750 	char *outstr;
751 	int ret;
752 
753 	ret = lpss_reg_read(dev, LPSS_GENERAL, &ltr_mode);
754 	if (ret)
755 		return ret;
756 
757 	outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
758 	return sprintf(buf, "%s\n", outstr);
759 }
760 
761 static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
762 static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
763 static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
764 
765 static struct attribute *lpss_attrs[] = {
766 	&dev_attr_auto_ltr.attr,
767 	&dev_attr_sw_ltr.attr,
768 	&dev_attr_ltr_mode.attr,
769 	NULL,
770 };
771 
772 static const struct attribute_group lpss_attr_group = {
773 	.attrs = lpss_attrs,
774 	.name = "lpss_ltr",
775 };
776 
777 static void acpi_lpss_set_ltr(struct device *dev, s32 val)
778 {
779 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
780 	u32 ltr_mode, ltr_val;
781 
782 	ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
783 	if (val < 0) {
784 		if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
785 			ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
786 			__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
787 		}
788 		return;
789 	}
790 	ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
791 	if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
792 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
793 		val = LPSS_LTR_MAX_VAL;
794 	} else if (val > LPSS_LTR_MAX_VAL) {
795 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
796 		val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
797 	} else {
798 		ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
799 	}
800 	ltr_val |= val;
801 	__lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
802 	if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
803 		ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
804 		__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
805 	}
806 }
807 
808 #ifdef CONFIG_PM
809 /**
810  * acpi_lpss_save_ctx() - Save the private registers of LPSS device
811  * @dev: LPSS device
812  * @pdata: pointer to the private data of the LPSS device
813  *
814  * Most LPSS devices have private registers which may loose their context when
815  * the device is powered down. acpi_lpss_save_ctx() saves those registers into
816  * prv_reg_ctx array.
817  */
818 static void acpi_lpss_save_ctx(struct device *dev,
819 			       struct lpss_private_data *pdata)
820 {
821 	unsigned int i;
822 
823 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
824 		unsigned long offset = i * sizeof(u32);
825 
826 		pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
827 		dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
828 			pdata->prv_reg_ctx[i], offset);
829 	}
830 }
831 
832 /**
833  * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
834  * @dev: LPSS device
835  * @pdata: pointer to the private data of the LPSS device
836  *
837  * Restores the registers that were previously stored with acpi_lpss_save_ctx().
838  */
839 static void acpi_lpss_restore_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 		__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
848 		dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
849 			pdata->prv_reg_ctx[i], offset);
850 	}
851 }
852 
853 static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
854 {
855 	/*
856 	 * The following delay is needed or the subsequent write operations may
857 	 * fail. The LPSS devices are actually PCI devices and the PCI spec
858 	 * expects 10ms delay before the device can be accessed after D3 to D0
859 	 * transition. However some platforms like BSW does not need this delay.
860 	 */
861 	unsigned int delay = 10;	/* default 10ms delay */
862 
863 	if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)
864 		delay = 0;
865 
866 	msleep(delay);
867 }
868 
869 static int acpi_lpss_activate(struct device *dev)
870 {
871 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
872 	int ret;
873 
874 	ret = acpi_dev_resume(dev);
875 	if (ret)
876 		return ret;
877 
878 	acpi_lpss_d3_to_d0_delay(pdata);
879 
880 	/*
881 	 * This is called only on ->probe() stage where a device is either in
882 	 * known state defined by BIOS or most likely powered off. Due to this
883 	 * we have to deassert reset line to be sure that ->probe() will
884 	 * recognize the device.
885 	 */
886 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
887 		lpss_deassert_reset(pdata);
888 
889 	return 0;
890 }
891 
892 static void acpi_lpss_dismiss(struct device *dev)
893 {
894 	acpi_dev_suspend(dev, false);
895 }
896 
897 /* IOSF SB for LPSS island */
898 #define LPSS_IOSF_UNIT_LPIOEP		0xA0
899 #define LPSS_IOSF_UNIT_LPIO1		0xAB
900 #define LPSS_IOSF_UNIT_LPIO2		0xAC
901 
902 #define LPSS_IOSF_PMCSR			0x84
903 #define LPSS_PMCSR_D0			0
904 #define LPSS_PMCSR_D3hot		3
905 #define LPSS_PMCSR_Dx_MASK		GENMASK(1, 0)
906 
907 #define LPSS_IOSF_GPIODEF0		0x154
908 #define LPSS_GPIODEF0_DMA1_D3		BIT(2)
909 #define LPSS_GPIODEF0_DMA2_D3		BIT(3)
910 #define LPSS_GPIODEF0_DMA_D3_MASK	GENMASK(3, 2)
911 #define LPSS_GPIODEF0_DMA_LLP		BIT(13)
912 
913 static DEFINE_MUTEX(lpss_iosf_mutex);
914 static bool lpss_iosf_d3_entered = true;
915 
916 static void lpss_iosf_enter_d3_state(void)
917 {
918 	u32 value1 = 0;
919 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
920 	u32 value2 = LPSS_PMCSR_D3hot;
921 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
922 	/*
923 	 * PMC provides an information about actual status of the LPSS devices.
924 	 * Here we read the values related to LPSS power island, i.e. LPSS
925 	 * devices, excluding both LPSS DMA controllers, along with SCC domain.
926 	 */
927 	u32 func_dis, d3_sts_0, pmc_status;
928 	int ret;
929 
930 	ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);
931 	if (ret)
932 		return;
933 
934 	mutex_lock(&lpss_iosf_mutex);
935 
936 	ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);
937 	if (ret)
938 		goto exit;
939 
940 	/*
941 	 * Get the status of entire LPSS power island per device basis.
942 	 * Shutdown both LPSS DMA controllers if and only if all other devices
943 	 * are already in D3hot.
944 	 */
945 	pmc_status = (~(d3_sts_0 | func_dis)) & pmc_atom_d3_mask;
946 	if (pmc_status)
947 		goto exit;
948 
949 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
950 			LPSS_IOSF_PMCSR, value2, mask2);
951 
952 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
953 			LPSS_IOSF_PMCSR, value2, mask2);
954 
955 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
956 			LPSS_IOSF_GPIODEF0, value1, mask1);
957 
958 	lpss_iosf_d3_entered = true;
959 
960 exit:
961 	mutex_unlock(&lpss_iosf_mutex);
962 }
963 
964 static void lpss_iosf_exit_d3_state(void)
965 {
966 	u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 |
967 		     LPSS_GPIODEF0_DMA_LLP;
968 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
969 	u32 value2 = LPSS_PMCSR_D0;
970 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
971 
972 	mutex_lock(&lpss_iosf_mutex);
973 
974 	if (!lpss_iosf_d3_entered)
975 		goto exit;
976 
977 	lpss_iosf_d3_entered = false;
978 
979 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
980 			LPSS_IOSF_GPIODEF0, value1, mask1);
981 
982 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
983 			LPSS_IOSF_PMCSR, value2, mask2);
984 
985 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
986 			LPSS_IOSF_PMCSR, value2, mask2);
987 
988 exit:
989 	mutex_unlock(&lpss_iosf_mutex);
990 }
991 
992 static int acpi_lpss_suspend(struct device *dev, bool wakeup)
993 {
994 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
995 	int ret;
996 
997 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
998 		acpi_lpss_save_ctx(dev, pdata);
999 
1000 	ret = acpi_dev_suspend(dev, wakeup);
1001 
1002 	/*
1003 	 * This call must be last in the sequence, otherwise PMC will return
1004 	 * wrong status for devices being about to be powered off. See
1005 	 * lpss_iosf_enter_d3_state() for further information.
1006 	 */
1007 	if (acpi_target_system_state() == ACPI_STATE_S0 &&
1008 	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1009 		lpss_iosf_enter_d3_state();
1010 
1011 	return ret;
1012 }
1013 
1014 static int acpi_lpss_resume(struct device *dev)
1015 {
1016 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1017 	int ret;
1018 
1019 	/*
1020 	 * This call is kept first to be in symmetry with
1021 	 * acpi_lpss_runtime_suspend() one.
1022 	 */
1023 	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1024 		lpss_iosf_exit_d3_state();
1025 
1026 	ret = acpi_dev_resume(dev);
1027 	if (ret)
1028 		return ret;
1029 
1030 	acpi_lpss_d3_to_d0_delay(pdata);
1031 
1032 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
1033 		acpi_lpss_restore_ctx(dev, pdata);
1034 
1035 	return 0;
1036 }
1037 
1038 #ifdef CONFIG_PM_SLEEP
1039 static int acpi_lpss_do_suspend_late(struct device *dev)
1040 {
1041 	int ret;
1042 
1043 	if (dev_pm_smart_suspend_and_suspended(dev))
1044 		return 0;
1045 
1046 	ret = pm_generic_suspend_late(dev);
1047 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1048 }
1049 
1050 static int acpi_lpss_suspend_late(struct device *dev)
1051 {
1052 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1053 
1054 	if (pdata->dev_desc->resume_from_noirq)
1055 		return 0;
1056 
1057 	return acpi_lpss_do_suspend_late(dev);
1058 }
1059 
1060 static int acpi_lpss_suspend_noirq(struct device *dev)
1061 {
1062 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1063 	int ret;
1064 
1065 	if (pdata->dev_desc->resume_from_noirq) {
1066 		/*
1067 		 * The driver's ->suspend_late callback will be invoked by
1068 		 * acpi_lpss_do_suspend_late(), with the assumption that the
1069 		 * driver really wanted to run that code in ->suspend_noirq, but
1070 		 * it could not run after acpi_dev_suspend() and the driver
1071 		 * expected the latter to be called in the "late" phase.
1072 		 */
1073 		ret = acpi_lpss_do_suspend_late(dev);
1074 		if (ret)
1075 			return ret;
1076 	}
1077 
1078 	return acpi_subsys_suspend_noirq(dev);
1079 }
1080 
1081 static int acpi_lpss_do_resume_early(struct device *dev)
1082 {
1083 	int ret = acpi_lpss_resume(dev);
1084 
1085 	return ret ? ret : pm_generic_resume_early(dev);
1086 }
1087 
1088 static int acpi_lpss_resume_early(struct device *dev)
1089 {
1090 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1091 
1092 	if (pdata->dev_desc->resume_from_noirq)
1093 		return 0;
1094 
1095 	return acpi_lpss_do_resume_early(dev);
1096 }
1097 
1098 static int acpi_lpss_resume_noirq(struct device *dev)
1099 {
1100 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1101 	int ret;
1102 
1103 	/* Follow acpi_subsys_resume_noirq(). */
1104 	if (dev_pm_may_skip_resume(dev))
1105 		return 0;
1106 
1107 	if (dev_pm_smart_suspend_and_suspended(dev))
1108 		pm_runtime_set_active(dev);
1109 
1110 	ret = pm_generic_resume_noirq(dev);
1111 	if (ret)
1112 		return ret;
1113 
1114 	if (!pdata->dev_desc->resume_from_noirq)
1115 		return 0;
1116 
1117 	/*
1118 	 * The driver's ->resume_early callback will be invoked by
1119 	 * acpi_lpss_do_resume_early(), with the assumption that the driver
1120 	 * really wanted to run that code in ->resume_noirq, but it could not
1121 	 * run before acpi_dev_resume() and the driver expected the latter to be
1122 	 * called in the "early" phase.
1123 	 */
1124 	return acpi_lpss_do_resume_early(dev);
1125 }
1126 
1127 static int acpi_lpss_do_restore_early(struct device *dev)
1128 {
1129 	int ret = acpi_lpss_resume(dev);
1130 
1131 	return ret ? ret : pm_generic_restore_early(dev);
1132 }
1133 
1134 static int acpi_lpss_restore_early(struct device *dev)
1135 {
1136 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1137 
1138 	if (pdata->dev_desc->resume_from_noirq)
1139 		return 0;
1140 
1141 	return acpi_lpss_do_restore_early(dev);
1142 }
1143 
1144 static int acpi_lpss_restore_noirq(struct device *dev)
1145 {
1146 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1147 	int ret;
1148 
1149 	ret = pm_generic_restore_noirq(dev);
1150 	if (ret)
1151 		return ret;
1152 
1153 	if (!pdata->dev_desc->resume_from_noirq)
1154 		return 0;
1155 
1156 	/* This is analogous to what happens in acpi_lpss_resume_noirq(). */
1157 	return acpi_lpss_do_restore_early(dev);
1158 }
1159 
1160 static int acpi_lpss_do_poweroff_late(struct device *dev)
1161 {
1162 	int ret = pm_generic_poweroff_late(dev);
1163 
1164 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1165 }
1166 
1167 static int acpi_lpss_poweroff_late(struct device *dev)
1168 {
1169 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1170 
1171 	if (dev_pm_smart_suspend_and_suspended(dev))
1172 		return 0;
1173 
1174 	if (pdata->dev_desc->resume_from_noirq)
1175 		return 0;
1176 
1177 	return acpi_lpss_do_poweroff_late(dev);
1178 }
1179 
1180 static int acpi_lpss_poweroff_noirq(struct device *dev)
1181 {
1182 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1183 
1184 	if (dev_pm_smart_suspend_and_suspended(dev))
1185 		return 0;
1186 
1187 	if (pdata->dev_desc->resume_from_noirq) {
1188 		/* This is analogous to the acpi_lpss_suspend_noirq() case. */
1189 		int ret = acpi_lpss_do_poweroff_late(dev);
1190 		if (ret)
1191 			return ret;
1192 	}
1193 
1194 	return pm_generic_poweroff_noirq(dev);
1195 }
1196 #endif /* CONFIG_PM_SLEEP */
1197 
1198 static int acpi_lpss_runtime_suspend(struct device *dev)
1199 {
1200 	int ret = pm_generic_runtime_suspend(dev);
1201 
1202 	return ret ? ret : acpi_lpss_suspend(dev, true);
1203 }
1204 
1205 static int acpi_lpss_runtime_resume(struct device *dev)
1206 {
1207 	int ret = acpi_lpss_resume(dev);
1208 
1209 	return ret ? ret : pm_generic_runtime_resume(dev);
1210 }
1211 #endif /* CONFIG_PM */
1212 
1213 static struct dev_pm_domain acpi_lpss_pm_domain = {
1214 #ifdef CONFIG_PM
1215 	.activate = acpi_lpss_activate,
1216 	.dismiss = acpi_lpss_dismiss,
1217 #endif
1218 	.ops = {
1219 #ifdef CONFIG_PM
1220 #ifdef CONFIG_PM_SLEEP
1221 		.prepare = acpi_subsys_prepare,
1222 		.complete = acpi_subsys_complete,
1223 		.suspend = acpi_subsys_suspend,
1224 		.suspend_late = acpi_lpss_suspend_late,
1225 		.suspend_noirq = acpi_lpss_suspend_noirq,
1226 		.resume_noirq = acpi_lpss_resume_noirq,
1227 		.resume_early = acpi_lpss_resume_early,
1228 		.freeze = acpi_subsys_freeze,
1229 		.poweroff = acpi_subsys_poweroff,
1230 		.poweroff_late = acpi_lpss_poweroff_late,
1231 		.poweroff_noirq = acpi_lpss_poweroff_noirq,
1232 		.restore_noirq = acpi_lpss_restore_noirq,
1233 		.restore_early = acpi_lpss_restore_early,
1234 #endif
1235 		.runtime_suspend = acpi_lpss_runtime_suspend,
1236 		.runtime_resume = acpi_lpss_runtime_resume,
1237 #endif
1238 	},
1239 };
1240 
1241 static int acpi_lpss_platform_notify(struct notifier_block *nb,
1242 				     unsigned long action, void *data)
1243 {
1244 	struct platform_device *pdev = to_platform_device(data);
1245 	struct lpss_private_data *pdata;
1246 	struct acpi_device *adev;
1247 	const struct acpi_device_id *id;
1248 
1249 	id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
1250 	if (!id || !id->driver_data)
1251 		return 0;
1252 
1253 	if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
1254 		return 0;
1255 
1256 	pdata = acpi_driver_data(adev);
1257 	if (!pdata)
1258 		return 0;
1259 
1260 	if (pdata->mmio_base &&
1261 	    pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
1262 		dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
1263 		return 0;
1264 	}
1265 
1266 	switch (action) {
1267 	case BUS_NOTIFY_BIND_DRIVER:
1268 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1269 		break;
1270 	case BUS_NOTIFY_DRIVER_NOT_BOUND:
1271 	case BUS_NOTIFY_UNBOUND_DRIVER:
1272 		dev_pm_domain_set(&pdev->dev, NULL);
1273 		break;
1274 	case BUS_NOTIFY_ADD_DEVICE:
1275 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1276 		if (pdata->dev_desc->flags & LPSS_LTR)
1277 			return sysfs_create_group(&pdev->dev.kobj,
1278 						  &lpss_attr_group);
1279 		break;
1280 	case BUS_NOTIFY_DEL_DEVICE:
1281 		if (pdata->dev_desc->flags & LPSS_LTR)
1282 			sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
1283 		dev_pm_domain_set(&pdev->dev, NULL);
1284 		break;
1285 	default:
1286 		break;
1287 	}
1288 
1289 	return 0;
1290 }
1291 
1292 static struct notifier_block acpi_lpss_nb = {
1293 	.notifier_call = acpi_lpss_platform_notify,
1294 };
1295 
1296 static void acpi_lpss_bind(struct device *dev)
1297 {
1298 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1299 
1300 	if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
1301 		return;
1302 
1303 	if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
1304 		dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
1305 	else
1306 		dev_err(dev, "MMIO size insufficient to access LTR\n");
1307 }
1308 
1309 static void acpi_lpss_unbind(struct device *dev)
1310 {
1311 	dev->power.set_latency_tolerance = NULL;
1312 }
1313 
1314 static struct acpi_scan_handler lpss_handler = {
1315 	.ids = acpi_lpss_device_ids,
1316 	.attach = acpi_lpss_create_device,
1317 	.bind = acpi_lpss_bind,
1318 	.unbind = acpi_lpss_unbind,
1319 };
1320 
1321 void __init acpi_lpss_init(void)
1322 {
1323 	const struct x86_cpu_id *id;
1324 	int ret;
1325 
1326 	ret = lpt_clk_init();
1327 	if (ret)
1328 		return;
1329 
1330 	id = x86_match_cpu(lpss_cpu_ids);
1331 	if (id)
1332 		lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;
1333 
1334 	bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
1335 	acpi_scan_add_handler(&lpss_handler);
1336 }
1337 
1338 #else
1339 
1340 static struct acpi_scan_handler lpss_handler = {
1341 	.ids = acpi_lpss_device_ids,
1342 };
1343 
1344 void __init acpi_lpss_init(void)
1345 {
1346 	acpi_scan_add_handler(&lpss_handler);
1347 }
1348 
1349 #endif /* CONFIG_X86_INTEL_LPSS */
1350