xref: /openbmc/linux/drivers/acpi/acpi_lpss.c (revision b1c3d2be)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ACPI support for Intel Lynxpoint LPSS.
4  *
5  * Copyright (C) 2013, Intel Corporation
6  * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
7  *          Rafael J. Wysocki <rafael.j.wysocki@intel.com>
8  */
9 
10 #include <linux/acpi.h>
11 #include <linux/clkdev.h>
12 #include <linux/clk-provider.h>
13 #include <linux/dmi.h>
14 #include <linux/err.h>
15 #include <linux/io.h>
16 #include <linux/mutex.h>
17 #include <linux/pci.h>
18 #include <linux/platform_device.h>
19 #include <linux/platform_data/x86/clk-lpss.h>
20 #include <linux/platform_data/x86/pmc_atom.h>
21 #include <linux/pm_domain.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/pwm.h>
24 #include <linux/pxa2xx_ssp.h>
25 #include <linux/suspend.h>
26 #include <linux/delay.h>
27 
28 #include "internal.h"
29 
30 #ifdef CONFIG_X86_INTEL_LPSS
31 
32 #include <asm/cpu_device_id.h>
33 #include <asm/intel-family.h>
34 #include <asm/iosf_mbi.h>
35 
36 #define LPSS_ADDR(desc) ((unsigned long)&desc)
37 
38 #define LPSS_CLK_SIZE	0x04
39 #define LPSS_LTR_SIZE	0x18
40 
41 /* Offsets relative to LPSS_PRIVATE_OFFSET */
42 #define LPSS_CLK_DIVIDER_DEF_MASK	(BIT(1) | BIT(16))
43 #define LPSS_RESETS			0x04
44 #define LPSS_RESETS_RESET_FUNC		BIT(0)
45 #define LPSS_RESETS_RESET_APB		BIT(1)
46 #define LPSS_GENERAL			0x08
47 #define LPSS_GENERAL_LTR_MODE_SW	BIT(2)
48 #define LPSS_GENERAL_UART_RTS_OVRD	BIT(3)
49 #define LPSS_SW_LTR			0x10
50 #define LPSS_AUTO_LTR			0x14
51 #define LPSS_LTR_SNOOP_REQ		BIT(15)
52 #define LPSS_LTR_SNOOP_MASK		0x0000FFFF
53 #define LPSS_LTR_SNOOP_LAT_1US		0x800
54 #define LPSS_LTR_SNOOP_LAT_32US		0xC00
55 #define LPSS_LTR_SNOOP_LAT_SHIFT	5
56 #define LPSS_LTR_SNOOP_LAT_CUTOFF	3000
57 #define LPSS_LTR_MAX_VAL		0x3FF
58 #define LPSS_TX_INT			0x20
59 #define LPSS_TX_INT_MASK		BIT(1)
60 
61 #define LPSS_PRV_REG_COUNT		9
62 
63 /* LPSS Flags */
64 #define LPSS_CLK			BIT(0)
65 #define LPSS_CLK_GATE			BIT(1)
66 #define LPSS_CLK_DIVIDER		BIT(2)
67 #define LPSS_LTR			BIT(3)
68 #define LPSS_SAVE_CTX			BIT(4)
69 /*
70  * For some devices the DSDT AML code for another device turns off the device
71  * before our suspend handler runs, causing us to read/save all 1-s (0xffffffff)
72  * as ctx register values.
73  * Luckily these devices always use the same ctx register values, so we can
74  * work around this by saving the ctx registers once on activation.
75  */
76 #define LPSS_SAVE_CTX_ONCE		BIT(5)
77 #define LPSS_NO_D3_DELAY		BIT(6)
78 
79 struct lpss_private_data;
80 
81 struct 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 
91 static const struct lpss_device_desc lpss_dma_desc = {
92 	.flags = LPSS_CLK,
93 };
94 
95 struct 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 */
106 static u32 pmc_atom_d3_mask = 0xfe000ffe;
107 
108 /* LPSS run time quirks */
109 static unsigned int lpss_quirks;
110 
111 /*
112  * LPSS_QUIRK_ALWAYS_POWER_ON: override power state for LPSS DMA device.
113  *
114  * The LPSS DMA controller has neither _PS0 nor _PS3 method. Moreover
115  * it can be powered off automatically whenever the last LPSS device goes down.
116  * In case of no power any access to the DMA controller will hang the system.
117  * The behaviour is reproduced on some HP laptops based on Intel BayTrail as
118  * well as on ASuS T100TA transformer.
119  *
120  * This quirk overrides power state of entire LPSS island to keep DMA powered
121  * on whenever we have at least one other device in use.
122  */
123 #define LPSS_QUIRK_ALWAYS_POWER_ON	BIT(0)
124 
125 /* UART Component Parameter Register */
126 #define LPSS_UART_CPR			0xF4
127 #define LPSS_UART_CPR_AFCE		BIT(4)
128 
129 static 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 
147 static void lpss_deassert_reset(struct lpss_private_data *pdata)
148 {
149 	unsigned int offset;
150 	u32 val;
151 
152 	offset = pdata->dev_desc->prv_offset + LPSS_RESETS;
153 	val = readl(pdata->mmio_base + offset);
154 	val |= LPSS_RESETS_RESET_APB | LPSS_RESETS_RESET_FUNC;
155 	writel(val, pdata->mmio_base + offset);
156 }
157 
158 /*
159  * BYT PWM used for backlight control by the i915 driver on systems without
160  * the Crystal Cove PMIC.
161  */
162 static 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 
168 static void byt_pwm_setup(struct lpss_private_data *pdata)
169 {
170 	u64 uid;
171 
172 	/* Only call pwm_add_table for the first PWM controller */
173 	if (acpi_dev_uid_to_integer(pdata->adev, &uid) || uid != 1)
174 		return;
175 
176 	pwm_add_table(byt_pwm_lookup, ARRAY_SIZE(byt_pwm_lookup));
177 }
178 
179 #define LPSS_I2C_ENABLE			0x6c
180 
181 static void byt_i2c_setup(struct lpss_private_data *pdata)
182 {
183 	acpi_handle handle = pdata->adev->handle;
184 	unsigned long long shared_host = 0;
185 	acpi_status status;
186 	u64 uid;
187 
188 	/* Expected to always be successfull, but better safe then sorry */
189 	if (!acpi_dev_uid_to_integer(pdata->adev, &uid) && uid) {
190 		/* Detect I2C bus shared with PUNIT and ignore its d3 status */
191 		status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host);
192 		if (ACPI_SUCCESS(status) && shared_host)
193 			pmc_atom_d3_mask &= ~(BIT_LPSS2_F1_I2C1 << (uid - 1));
194 	}
195 
196 	lpss_deassert_reset(pdata);
197 
198 	if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset))
199 		pdata->fixed_clk_rate = 133000000;
200 
201 	writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
202 }
203 
204 /* BSW PWM used for backlight control by the i915 driver */
205 static struct pwm_lookup bsw_pwm_lookup[] = {
206 	PWM_LOOKUP_WITH_MODULE("80862288:00", 0, "0000:00:02.0",
207 			       "pwm_soc_backlight", 0, PWM_POLARITY_NORMAL,
208 			       "pwm-lpss-platform"),
209 };
210 
211 static void bsw_pwm_setup(struct lpss_private_data *pdata)
212 {
213 	u64 uid;
214 
215 	/* Only call pwm_add_table for the first PWM controller */
216 	if (acpi_dev_uid_to_integer(pdata->adev, &uid) || uid != 1)
217 		return;
218 
219 	pwm_add_table(bsw_pwm_lookup, ARRAY_SIZE(bsw_pwm_lookup));
220 }
221 
222 static const struct property_entry lpt_spi_properties[] = {
223 	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_LPT_SSP),
224 	{ }
225 };
226 
227 static const struct lpss_device_desc lpt_spi_dev_desc = {
228 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR
229 			| LPSS_SAVE_CTX,
230 	.prv_offset = 0x800,
231 	.properties = lpt_spi_properties,
232 };
233 
234 static 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 
239 static 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 
246 static const struct lpss_device_desc lpt_uart_dev_desc = {
247 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR
248 			| LPSS_SAVE_CTX,
249 	.clk_con_id = "baudclk",
250 	.prv_offset = 0x800,
251 	.setup = lpss_uart_setup,
252 	.properties = uart_properties,
253 };
254 
255 static const struct lpss_device_desc lpt_sdio_dev_desc = {
256 	.flags = LPSS_LTR,
257 	.prv_offset = 0x1000,
258 	.prv_size_override = 0x1018,
259 };
260 
261 static 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 
267 static 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 
274 static const struct lpss_device_desc byt_uart_dev_desc = {
275 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
276 	.clk_con_id = "baudclk",
277 	.prv_offset = 0x800,
278 	.setup = lpss_uart_setup,
279 	.properties = uart_properties,
280 };
281 
282 static const struct lpss_device_desc bsw_uart_dev_desc = {
283 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
284 			| LPSS_NO_D3_DELAY,
285 	.clk_con_id = "baudclk",
286 	.prv_offset = 0x800,
287 	.setup = lpss_uart_setup,
288 	.properties = uart_properties,
289 };
290 
291 static const struct property_entry byt_spi_properties[] = {
292 	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_BYT_SSP),
293 	{ }
294 };
295 
296 static const struct lpss_device_desc byt_spi_dev_desc = {
297 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
298 	.prv_offset = 0x400,
299 	.properties = byt_spi_properties,
300 };
301 
302 static const struct lpss_device_desc byt_sdio_dev_desc = {
303 	.flags = LPSS_CLK,
304 };
305 
306 static const struct lpss_device_desc byt_i2c_dev_desc = {
307 	.flags = LPSS_CLK | LPSS_SAVE_CTX,
308 	.prv_offset = 0x800,
309 	.setup = byt_i2c_setup,
310 	.resume_from_noirq = true,
311 };
312 
313 static const struct lpss_device_desc bsw_i2c_dev_desc = {
314 	.flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
315 	.prv_offset = 0x800,
316 	.setup = byt_i2c_setup,
317 	.resume_from_noirq = true,
318 };
319 
320 static const struct property_entry bsw_spi_properties[] = {
321 	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_BSW_SSP),
322 	{ }
323 };
324 
325 static const struct lpss_device_desc bsw_spi_dev_desc = {
326 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
327 			| LPSS_NO_D3_DELAY,
328 	.prv_offset = 0x400,
329 	.setup = lpss_deassert_reset,
330 	.properties = bsw_spi_properties,
331 };
332 
333 static const struct x86_cpu_id lpss_cpu_ids[] = {
334 	X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT,	NULL),
335 	X86_MATCH_INTEL_FAM6_MODEL(ATOM_AIRMONT,	NULL),
336 	{}
337 };
338 
339 #else
340 
341 #define LPSS_ADDR(desc) (0UL)
342 
343 #endif /* CONFIG_X86_INTEL_LPSS */
344 
345 static const struct acpi_device_id acpi_lpss_device_ids[] = {
346 	/* Generic LPSS devices */
347 	{ "INTL9C60", LPSS_ADDR(lpss_dma_desc) },
348 
349 	/* Lynxpoint LPSS devices */
350 	{ "INT33C0", LPSS_ADDR(lpt_spi_dev_desc) },
351 	{ "INT33C1", LPSS_ADDR(lpt_spi_dev_desc) },
352 	{ "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },
353 	{ "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },
354 	{ "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },
355 	{ "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },
356 	{ "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },
357 	{ "INT33C7", },
358 
359 	/* BayTrail LPSS devices */
360 	{ "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },
361 	{ "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },
362 	{ "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },
363 	{ "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },
364 	{ "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },
365 	{ "INT33B2", },
366 	{ "INT33FC", },
367 
368 	/* Braswell LPSS devices */
369 	{ "80862286", LPSS_ADDR(lpss_dma_desc) },
370 	{ "80862288", LPSS_ADDR(bsw_pwm_dev_desc) },
371 	{ "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },
372 	{ "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },
373 	{ "808622C0", LPSS_ADDR(lpss_dma_desc) },
374 	{ "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) },
375 
376 	/* Broadwell LPSS devices */
377 	{ "INT3430", LPSS_ADDR(lpt_spi_dev_desc) },
378 	{ "INT3431", LPSS_ADDR(lpt_spi_dev_desc) },
379 	{ "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },
380 	{ "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },
381 	{ "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },
382 	{ "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },
383 	{ "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },
384 	{ "INT3437", },
385 
386 	/* Wildcat Point LPSS devices */
387 	{ "INT3438", LPSS_ADDR(lpt_spi_dev_desc) },
388 
389 	{ }
390 };
391 
392 #ifdef CONFIG_X86_INTEL_LPSS
393 
394 /* LPSS main clock device. */
395 static struct platform_device *lpss_clk_dev;
396 
397 static inline void lpt_register_clock_device(void)
398 {
399 	lpss_clk_dev = platform_device_register_simple("clk-lpss-atom",
400 						       PLATFORM_DEVID_NONE,
401 						       NULL, 0);
402 }
403 
404 static int register_device_clock(struct acpi_device *adev,
405 				 struct lpss_private_data *pdata)
406 {
407 	const struct lpss_device_desc *dev_desc = pdata->dev_desc;
408 	const char *devname = dev_name(&adev->dev);
409 	struct clk *clk;
410 	struct lpss_clk_data *clk_data;
411 	const char *parent, *clk_name;
412 	void __iomem *prv_base;
413 
414 	if (!lpss_clk_dev)
415 		lpt_register_clock_device();
416 
417 	if (IS_ERR(lpss_clk_dev))
418 		return PTR_ERR(lpss_clk_dev);
419 
420 	clk_data = platform_get_drvdata(lpss_clk_dev);
421 	if (!clk_data)
422 		return -ENODEV;
423 	clk = clk_data->clk;
424 
425 	if (!pdata->mmio_base
426 	    || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
427 		return -ENODATA;
428 
429 	parent = clk_data->name;
430 	prv_base = pdata->mmio_base + dev_desc->prv_offset;
431 
432 	if (pdata->fixed_clk_rate) {
433 		clk = clk_register_fixed_rate(NULL, devname, parent, 0,
434 					      pdata->fixed_clk_rate);
435 		goto out;
436 	}
437 
438 	if (dev_desc->flags & LPSS_CLK_GATE) {
439 		clk = clk_register_gate(NULL, devname, parent, 0,
440 					prv_base, 0, 0, NULL);
441 		parent = devname;
442 	}
443 
444 	if (dev_desc->flags & LPSS_CLK_DIVIDER) {
445 		/* Prevent division by zero */
446 		if (!readl(prv_base))
447 			writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
448 
449 		clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
450 		if (!clk_name)
451 			return -ENOMEM;
452 		clk = clk_register_fractional_divider(NULL, clk_name, parent,
453 						      CLK_FRAC_DIVIDER_POWER_OF_TWO_PS,
454 						      prv_base, 1, 15, 16, 15, 0, NULL);
455 		parent = clk_name;
456 
457 		clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
458 		if (!clk_name) {
459 			kfree(parent);
460 			return -ENOMEM;
461 		}
462 		clk = clk_register_gate(NULL, clk_name, parent,
463 					CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
464 					prv_base, 31, 0, NULL);
465 		kfree(parent);
466 		kfree(clk_name);
467 	}
468 out:
469 	if (IS_ERR(clk))
470 		return PTR_ERR(clk);
471 
472 	pdata->clk = clk;
473 	clk_register_clkdev(clk, dev_desc->clk_con_id, devname);
474 	return 0;
475 }
476 
477 struct lpss_device_links {
478 	const char *supplier_hid;
479 	const char *supplier_uid;
480 	const char *consumer_hid;
481 	const char *consumer_uid;
482 	u32 flags;
483 	const struct dmi_system_id *dep_missing_ids;
484 };
485 
486 /* Please keep this list sorted alphabetically by vendor and model */
487 static const struct dmi_system_id i2c1_dep_missing_dmi_ids[] = {
488 	{
489 		.matches = {
490 			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
491 			DMI_MATCH(DMI_PRODUCT_NAME, "T200TA"),
492 		},
493 	},
494 	{}
495 };
496 
497 /*
498  * The _DEP method is used to identify dependencies but instead of creating
499  * device links for every handle in _DEP, only links in the following list are
500  * created. That is necessary because, in the general case, _DEP can refer to
501  * devices that might not have drivers, or that are on different buses, or where
502  * the supplier is not enumerated until after the consumer is probed.
503  */
504 static const struct lpss_device_links lpss_device_links[] = {
505 	/* CHT External sdcard slot controller depends on PMIC I2C ctrl */
506 	{"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME},
507 	/* CHT iGPU depends on PMIC I2C controller */
508 	{"808622C1", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
509 	/* BYT iGPU depends on the Embedded Controller I2C controller (UID 1) */
510 	{"80860F41", "1", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME,
511 	 i2c1_dep_missing_dmi_ids},
512 	/* BYT CR iGPU depends on PMIC I2C controller (UID 5 on CR) */
513 	{"80860F41", "5", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
514 	/* BYT iGPU depends on PMIC I2C controller (UID 7 on non CR) */
515 	{"80860F41", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
516 };
517 
518 static bool acpi_lpss_is_supplier(struct acpi_device *adev,
519 				  const struct lpss_device_links *link)
520 {
521 	return acpi_dev_hid_uid_match(adev, link->supplier_hid, link->supplier_uid);
522 }
523 
524 static bool acpi_lpss_is_consumer(struct acpi_device *adev,
525 				  const struct lpss_device_links *link)
526 {
527 	return acpi_dev_hid_uid_match(adev, link->consumer_hid, link->consumer_uid);
528 }
529 
530 struct hid_uid {
531 	const char *hid;
532 	const char *uid;
533 };
534 
535 static int match_hid_uid(struct device *dev, const void *data)
536 {
537 	struct acpi_device *adev = ACPI_COMPANION(dev);
538 	const struct hid_uid *id = data;
539 
540 	if (!adev)
541 		return 0;
542 
543 	return acpi_dev_hid_uid_match(adev, id->hid, id->uid);
544 }
545 
546 static struct device *acpi_lpss_find_device(const char *hid, const char *uid)
547 {
548 	struct device *dev;
549 
550 	struct hid_uid data = {
551 		.hid = hid,
552 		.uid = uid,
553 	};
554 
555 	dev = bus_find_device(&platform_bus_type, NULL, &data, match_hid_uid);
556 	if (dev)
557 		return dev;
558 
559 	return bus_find_device(&pci_bus_type, NULL, &data, match_hid_uid);
560 }
561 
562 static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle)
563 {
564 	struct acpi_handle_list dep_devices;
565 	acpi_status status;
566 	int i;
567 
568 	if (!acpi_has_method(adev->handle, "_DEP"))
569 		return false;
570 
571 	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
572 					 &dep_devices);
573 	if (ACPI_FAILURE(status)) {
574 		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
575 		return false;
576 	}
577 
578 	for (i = 0; i < dep_devices.count; i++) {
579 		if (dep_devices.handles[i] == handle)
580 			return true;
581 	}
582 
583 	return false;
584 }
585 
586 static void acpi_lpss_link_consumer(struct device *dev1,
587 				    const struct lpss_device_links *link)
588 {
589 	struct device *dev2;
590 
591 	dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid);
592 	if (!dev2)
593 		return;
594 
595 	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
596 	    || acpi_lpss_dep(ACPI_COMPANION(dev2), ACPI_HANDLE(dev1)))
597 		device_link_add(dev2, dev1, link->flags);
598 
599 	put_device(dev2);
600 }
601 
602 static void acpi_lpss_link_supplier(struct device *dev1,
603 				    const struct lpss_device_links *link)
604 {
605 	struct device *dev2;
606 
607 	dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid);
608 	if (!dev2)
609 		return;
610 
611 	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
612 	    || acpi_lpss_dep(ACPI_COMPANION(dev1), ACPI_HANDLE(dev2)))
613 		device_link_add(dev1, dev2, link->flags);
614 
615 	put_device(dev2);
616 }
617 
618 static void acpi_lpss_create_device_links(struct acpi_device *adev,
619 					  struct platform_device *pdev)
620 {
621 	int i;
622 
623 	for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) {
624 		const struct lpss_device_links *link = &lpss_device_links[i];
625 
626 		if (acpi_lpss_is_supplier(adev, link))
627 			acpi_lpss_link_consumer(&pdev->dev, link);
628 
629 		if (acpi_lpss_is_consumer(adev, link))
630 			acpi_lpss_link_supplier(&pdev->dev, link);
631 	}
632 }
633 
634 static int acpi_lpss_create_device(struct acpi_device *adev,
635 				   const struct acpi_device_id *id)
636 {
637 	const struct lpss_device_desc *dev_desc;
638 	struct lpss_private_data *pdata;
639 	struct resource_entry *rentry;
640 	struct list_head resource_list;
641 	struct platform_device *pdev;
642 	int ret;
643 
644 	dev_desc = (const struct lpss_device_desc *)id->driver_data;
645 	if (!dev_desc) {
646 		pdev = acpi_create_platform_device(adev, NULL);
647 		return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
648 	}
649 	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
650 	if (!pdata)
651 		return -ENOMEM;
652 
653 	INIT_LIST_HEAD(&resource_list);
654 	ret = acpi_dev_get_memory_resources(adev, &resource_list);
655 	if (ret < 0)
656 		goto err_out;
657 
658 	rentry = list_first_entry_or_null(&resource_list, struct resource_entry, node);
659 	if (rentry) {
660 		if (dev_desc->prv_size_override)
661 			pdata->mmio_size = dev_desc->prv_size_override;
662 		else
663 			pdata->mmio_size = resource_size(rentry->res);
664 		pdata->mmio_base = ioremap(rentry->res->start, pdata->mmio_size);
665 	}
666 
667 	acpi_dev_free_resource_list(&resource_list);
668 
669 	if (!pdata->mmio_base) {
670 		/* Avoid acpi_bus_attach() instantiating a pdev for this dev. */
671 		adev->pnp.type.platform_id = 0;
672 		goto out_free;
673 	}
674 
675 	pdata->adev = adev;
676 	pdata->dev_desc = dev_desc;
677 
678 	if (dev_desc->setup)
679 		dev_desc->setup(pdata);
680 
681 	if (dev_desc->flags & LPSS_CLK) {
682 		ret = register_device_clock(adev, pdata);
683 		if (ret)
684 			goto out_free;
685 	}
686 
687 	/*
688 	 * This works around a known issue in ACPI tables where LPSS devices
689 	 * have _PS0 and _PS3 without _PSC (and no power resources), so
690 	 * acpi_bus_init_power() will assume that the BIOS has put them into D0.
691 	 */
692 	acpi_device_fix_up_power(adev);
693 
694 	adev->driver_data = pdata;
695 	pdev = acpi_create_platform_device(adev, dev_desc->properties);
696 	if (IS_ERR_OR_NULL(pdev)) {
697 		adev->driver_data = NULL;
698 		ret = PTR_ERR(pdev);
699 		goto err_out;
700 	}
701 
702 	acpi_lpss_create_device_links(adev, pdev);
703 	return 1;
704 
705 out_free:
706 	/* Skip the device, but continue the namespace scan */
707 	ret = 0;
708 err_out:
709 	kfree(pdata);
710 	return ret;
711 }
712 
713 static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
714 {
715 	return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
716 }
717 
718 static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
719 			     unsigned int reg)
720 {
721 	writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
722 }
723 
724 static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
725 {
726 	struct acpi_device *adev = ACPI_COMPANION(dev);
727 	struct lpss_private_data *pdata;
728 	unsigned long flags;
729 	int ret;
730 
731 	if (WARN_ON(!adev))
732 		return -ENODEV;
733 
734 	spin_lock_irqsave(&dev->power.lock, flags);
735 	if (pm_runtime_suspended(dev)) {
736 		ret = -EAGAIN;
737 		goto out;
738 	}
739 	pdata = acpi_driver_data(adev);
740 	if (WARN_ON(!pdata || !pdata->mmio_base)) {
741 		ret = -ENODEV;
742 		goto out;
743 	}
744 	*val = __lpss_reg_read(pdata, reg);
745 	ret = 0;
746 
747  out:
748 	spin_unlock_irqrestore(&dev->power.lock, flags);
749 	return ret;
750 }
751 
752 static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
753 			     char *buf)
754 {
755 	u32 ltr_value = 0;
756 	unsigned int reg;
757 	int ret;
758 
759 	reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
760 	ret = lpss_reg_read(dev, reg, &ltr_value);
761 	if (ret)
762 		return ret;
763 
764 	return sysfs_emit(buf, "%08x\n", ltr_value);
765 }
766 
767 static ssize_t lpss_ltr_mode_show(struct device *dev,
768 				  struct device_attribute *attr, char *buf)
769 {
770 	u32 ltr_mode = 0;
771 	char *outstr;
772 	int ret;
773 
774 	ret = lpss_reg_read(dev, LPSS_GENERAL, &ltr_mode);
775 	if (ret)
776 		return ret;
777 
778 	outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
779 	return sprintf(buf, "%s\n", outstr);
780 }
781 
782 static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
783 static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
784 static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
785 
786 static struct attribute *lpss_attrs[] = {
787 	&dev_attr_auto_ltr.attr,
788 	&dev_attr_sw_ltr.attr,
789 	&dev_attr_ltr_mode.attr,
790 	NULL,
791 };
792 
793 static const struct attribute_group lpss_attr_group = {
794 	.attrs = lpss_attrs,
795 	.name = "lpss_ltr",
796 };
797 
798 static void acpi_lpss_set_ltr(struct device *dev, s32 val)
799 {
800 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
801 	u32 ltr_mode, ltr_val;
802 
803 	ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
804 	if (val < 0) {
805 		if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
806 			ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
807 			__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
808 		}
809 		return;
810 	}
811 	ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
812 	if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
813 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
814 		val = LPSS_LTR_MAX_VAL;
815 	} else if (val > LPSS_LTR_MAX_VAL) {
816 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
817 		val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
818 	} else {
819 		ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
820 	}
821 	ltr_val |= val;
822 	__lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
823 	if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
824 		ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
825 		__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
826 	}
827 }
828 
829 #ifdef CONFIG_PM
830 /**
831  * acpi_lpss_save_ctx() - Save the private registers of LPSS device
832  * @dev: LPSS device
833  * @pdata: pointer to the private data of the LPSS device
834  *
835  * Most LPSS devices have private registers which may loose their context when
836  * the device is powered down. acpi_lpss_save_ctx() saves those registers into
837  * prv_reg_ctx array.
838  */
839 static void acpi_lpss_save_ctx(struct device *dev,
840 			       struct lpss_private_data *pdata)
841 {
842 	unsigned int i;
843 
844 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
845 		unsigned long offset = i * sizeof(u32);
846 
847 		pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
848 		dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
849 			pdata->prv_reg_ctx[i], offset);
850 	}
851 }
852 
853 /**
854  * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
855  * @dev: LPSS device
856  * @pdata: pointer to the private data of the LPSS device
857  *
858  * Restores the registers that were previously stored with acpi_lpss_save_ctx().
859  */
860 static void acpi_lpss_restore_ctx(struct device *dev,
861 				  struct lpss_private_data *pdata)
862 {
863 	unsigned int i;
864 
865 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
866 		unsigned long offset = i * sizeof(u32);
867 
868 		__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
869 		dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
870 			pdata->prv_reg_ctx[i], offset);
871 	}
872 }
873 
874 static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
875 {
876 	/*
877 	 * The following delay is needed or the subsequent write operations may
878 	 * fail. The LPSS devices are actually PCI devices and the PCI spec
879 	 * expects 10ms delay before the device can be accessed after D3 to D0
880 	 * transition. However some platforms like BSW does not need this delay.
881 	 */
882 	unsigned int delay = 10;	/* default 10ms delay */
883 
884 	if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)
885 		delay = 0;
886 
887 	msleep(delay);
888 }
889 
890 static int acpi_lpss_activate(struct device *dev)
891 {
892 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
893 	int ret;
894 
895 	ret = acpi_dev_resume(dev);
896 	if (ret)
897 		return ret;
898 
899 	acpi_lpss_d3_to_d0_delay(pdata);
900 
901 	/*
902 	 * This is called only on ->probe() stage where a device is either in
903 	 * known state defined by BIOS or most likely powered off. Due to this
904 	 * we have to deassert reset line to be sure that ->probe() will
905 	 * recognize the device.
906 	 */
907 	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
908 		lpss_deassert_reset(pdata);
909 
910 #ifdef CONFIG_PM
911 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX_ONCE)
912 		acpi_lpss_save_ctx(dev, pdata);
913 #endif
914 
915 	return 0;
916 }
917 
918 static void acpi_lpss_dismiss(struct device *dev)
919 {
920 	acpi_dev_suspend(dev, false);
921 }
922 
923 /* IOSF SB for LPSS island */
924 #define LPSS_IOSF_UNIT_LPIOEP		0xA0
925 #define LPSS_IOSF_UNIT_LPIO1		0xAB
926 #define LPSS_IOSF_UNIT_LPIO2		0xAC
927 
928 #define LPSS_IOSF_PMCSR			0x84
929 #define LPSS_PMCSR_D0			0
930 #define LPSS_PMCSR_D3hot		3
931 #define LPSS_PMCSR_Dx_MASK		GENMASK(1, 0)
932 
933 #define LPSS_IOSF_GPIODEF0		0x154
934 #define LPSS_GPIODEF0_DMA1_D3		BIT(2)
935 #define LPSS_GPIODEF0_DMA2_D3		BIT(3)
936 #define LPSS_GPIODEF0_DMA_D3_MASK	GENMASK(3, 2)
937 #define LPSS_GPIODEF0_DMA_LLP		BIT(13)
938 
939 static DEFINE_MUTEX(lpss_iosf_mutex);
940 static bool lpss_iosf_d3_entered = true;
941 
942 static void lpss_iosf_enter_d3_state(void)
943 {
944 	u32 value1 = 0;
945 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
946 	u32 value2 = LPSS_PMCSR_D3hot;
947 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
948 	/*
949 	 * PMC provides an information about actual status of the LPSS devices.
950 	 * Here we read the values related to LPSS power island, i.e. LPSS
951 	 * devices, excluding both LPSS DMA controllers, along with SCC domain.
952 	 */
953 	u32 func_dis, d3_sts_0, pmc_status;
954 	int ret;
955 
956 	ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);
957 	if (ret)
958 		return;
959 
960 	mutex_lock(&lpss_iosf_mutex);
961 
962 	ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);
963 	if (ret)
964 		goto exit;
965 
966 	/*
967 	 * Get the status of entire LPSS power island per device basis.
968 	 * Shutdown both LPSS DMA controllers if and only if all other devices
969 	 * are already in D3hot.
970 	 */
971 	pmc_status = (~(d3_sts_0 | func_dis)) & pmc_atom_d3_mask;
972 	if (pmc_status)
973 		goto exit;
974 
975 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
976 			LPSS_IOSF_PMCSR, value2, mask2);
977 
978 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
979 			LPSS_IOSF_PMCSR, value2, mask2);
980 
981 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
982 			LPSS_IOSF_GPIODEF0, value1, mask1);
983 
984 	lpss_iosf_d3_entered = true;
985 
986 exit:
987 	mutex_unlock(&lpss_iosf_mutex);
988 }
989 
990 static void lpss_iosf_exit_d3_state(void)
991 {
992 	u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 |
993 		     LPSS_GPIODEF0_DMA_LLP;
994 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
995 	u32 value2 = LPSS_PMCSR_D0;
996 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
997 
998 	mutex_lock(&lpss_iosf_mutex);
999 
1000 	if (!lpss_iosf_d3_entered)
1001 		goto exit;
1002 
1003 	lpss_iosf_d3_entered = false;
1004 
1005 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
1006 			LPSS_IOSF_GPIODEF0, value1, mask1);
1007 
1008 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
1009 			LPSS_IOSF_PMCSR, value2, mask2);
1010 
1011 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
1012 			LPSS_IOSF_PMCSR, value2, mask2);
1013 
1014 exit:
1015 	mutex_unlock(&lpss_iosf_mutex);
1016 }
1017 
1018 static int acpi_lpss_suspend(struct device *dev, bool wakeup)
1019 {
1020 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1021 	int ret;
1022 
1023 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
1024 		acpi_lpss_save_ctx(dev, pdata);
1025 
1026 	ret = acpi_dev_suspend(dev, wakeup);
1027 
1028 	/*
1029 	 * This call must be last in the sequence, otherwise PMC will return
1030 	 * wrong status for devices being about to be powered off. See
1031 	 * lpss_iosf_enter_d3_state() for further information.
1032 	 */
1033 	if (acpi_target_system_state() == ACPI_STATE_S0 &&
1034 	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1035 		lpss_iosf_enter_d3_state();
1036 
1037 	return ret;
1038 }
1039 
1040 static int acpi_lpss_resume(struct device *dev)
1041 {
1042 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1043 	int ret;
1044 
1045 	/*
1046 	 * This call is kept first to be in symmetry with
1047 	 * acpi_lpss_runtime_suspend() one.
1048 	 */
1049 	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1050 		lpss_iosf_exit_d3_state();
1051 
1052 	ret = acpi_dev_resume(dev);
1053 	if (ret)
1054 		return ret;
1055 
1056 	acpi_lpss_d3_to_d0_delay(pdata);
1057 
1058 	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
1059 		acpi_lpss_restore_ctx(dev, pdata);
1060 
1061 	return 0;
1062 }
1063 
1064 #ifdef CONFIG_PM_SLEEP
1065 static int acpi_lpss_do_suspend_late(struct device *dev)
1066 {
1067 	int ret;
1068 
1069 	if (dev_pm_skip_suspend(dev))
1070 		return 0;
1071 
1072 	ret = pm_generic_suspend_late(dev);
1073 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1074 }
1075 
1076 static int acpi_lpss_suspend_late(struct device *dev)
1077 {
1078 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1079 
1080 	if (pdata->dev_desc->resume_from_noirq)
1081 		return 0;
1082 
1083 	return acpi_lpss_do_suspend_late(dev);
1084 }
1085 
1086 static int acpi_lpss_suspend_noirq(struct device *dev)
1087 {
1088 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1089 	int ret;
1090 
1091 	if (pdata->dev_desc->resume_from_noirq) {
1092 		/*
1093 		 * The driver's ->suspend_late callback will be invoked by
1094 		 * acpi_lpss_do_suspend_late(), with the assumption that the
1095 		 * driver really wanted to run that code in ->suspend_noirq, but
1096 		 * it could not run after acpi_dev_suspend() and the driver
1097 		 * expected the latter to be called in the "late" phase.
1098 		 */
1099 		ret = acpi_lpss_do_suspend_late(dev);
1100 		if (ret)
1101 			return ret;
1102 	}
1103 
1104 	return acpi_subsys_suspend_noirq(dev);
1105 }
1106 
1107 static int acpi_lpss_do_resume_early(struct device *dev)
1108 {
1109 	int ret = acpi_lpss_resume(dev);
1110 
1111 	return ret ? ret : pm_generic_resume_early(dev);
1112 }
1113 
1114 static int acpi_lpss_resume_early(struct device *dev)
1115 {
1116 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1117 
1118 	if (pdata->dev_desc->resume_from_noirq)
1119 		return 0;
1120 
1121 	if (dev_pm_skip_resume(dev))
1122 		return 0;
1123 
1124 	return acpi_lpss_do_resume_early(dev);
1125 }
1126 
1127 static int acpi_lpss_resume_noirq(struct device *dev)
1128 {
1129 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1130 	int ret;
1131 
1132 	/* Follow acpi_subsys_resume_noirq(). */
1133 	if (dev_pm_skip_resume(dev))
1134 		return 0;
1135 
1136 	ret = pm_generic_resume_noirq(dev);
1137 	if (ret)
1138 		return ret;
1139 
1140 	if (!pdata->dev_desc->resume_from_noirq)
1141 		return 0;
1142 
1143 	/*
1144 	 * The driver's ->resume_early callback will be invoked by
1145 	 * acpi_lpss_do_resume_early(), with the assumption that the driver
1146 	 * really wanted to run that code in ->resume_noirq, but it could not
1147 	 * run before acpi_dev_resume() and the driver expected the latter to be
1148 	 * called in the "early" phase.
1149 	 */
1150 	return acpi_lpss_do_resume_early(dev);
1151 }
1152 
1153 static int acpi_lpss_do_restore_early(struct device *dev)
1154 {
1155 	int ret = acpi_lpss_resume(dev);
1156 
1157 	return ret ? ret : pm_generic_restore_early(dev);
1158 }
1159 
1160 static int acpi_lpss_restore_early(struct device *dev)
1161 {
1162 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1163 
1164 	if (pdata->dev_desc->resume_from_noirq)
1165 		return 0;
1166 
1167 	return acpi_lpss_do_restore_early(dev);
1168 }
1169 
1170 static int acpi_lpss_restore_noirq(struct device *dev)
1171 {
1172 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1173 	int ret;
1174 
1175 	ret = pm_generic_restore_noirq(dev);
1176 	if (ret)
1177 		return ret;
1178 
1179 	if (!pdata->dev_desc->resume_from_noirq)
1180 		return 0;
1181 
1182 	/* This is analogous to what happens in acpi_lpss_resume_noirq(). */
1183 	return acpi_lpss_do_restore_early(dev);
1184 }
1185 
1186 static int acpi_lpss_do_poweroff_late(struct device *dev)
1187 {
1188 	int ret = pm_generic_poweroff_late(dev);
1189 
1190 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1191 }
1192 
1193 static int acpi_lpss_poweroff_late(struct device *dev)
1194 {
1195 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1196 
1197 	if (dev_pm_skip_suspend(dev))
1198 		return 0;
1199 
1200 	if (pdata->dev_desc->resume_from_noirq)
1201 		return 0;
1202 
1203 	return acpi_lpss_do_poweroff_late(dev);
1204 }
1205 
1206 static int acpi_lpss_poweroff_noirq(struct device *dev)
1207 {
1208 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1209 
1210 	if (dev_pm_skip_suspend(dev))
1211 		return 0;
1212 
1213 	if (pdata->dev_desc->resume_from_noirq) {
1214 		/* This is analogous to the acpi_lpss_suspend_noirq() case. */
1215 		int ret = acpi_lpss_do_poweroff_late(dev);
1216 
1217 		if (ret)
1218 			return ret;
1219 	}
1220 
1221 	return pm_generic_poweroff_noirq(dev);
1222 }
1223 #endif /* CONFIG_PM_SLEEP */
1224 
1225 static int acpi_lpss_runtime_suspend(struct device *dev)
1226 {
1227 	int ret = pm_generic_runtime_suspend(dev);
1228 
1229 	return ret ? ret : acpi_lpss_suspend(dev, true);
1230 }
1231 
1232 static int acpi_lpss_runtime_resume(struct device *dev)
1233 {
1234 	int ret = acpi_lpss_resume(dev);
1235 
1236 	return ret ? ret : pm_generic_runtime_resume(dev);
1237 }
1238 #endif /* CONFIG_PM */
1239 
1240 static struct dev_pm_domain acpi_lpss_pm_domain = {
1241 #ifdef CONFIG_PM
1242 	.activate = acpi_lpss_activate,
1243 	.dismiss = acpi_lpss_dismiss,
1244 #endif
1245 	.ops = {
1246 #ifdef CONFIG_PM
1247 #ifdef CONFIG_PM_SLEEP
1248 		.prepare = acpi_subsys_prepare,
1249 		.complete = acpi_subsys_complete,
1250 		.suspend = acpi_subsys_suspend,
1251 		.suspend_late = acpi_lpss_suspend_late,
1252 		.suspend_noirq = acpi_lpss_suspend_noirq,
1253 		.resume_noirq = acpi_lpss_resume_noirq,
1254 		.resume_early = acpi_lpss_resume_early,
1255 		.freeze = acpi_subsys_freeze,
1256 		.poweroff = acpi_subsys_poweroff,
1257 		.poweroff_late = acpi_lpss_poweroff_late,
1258 		.poweroff_noirq = acpi_lpss_poweroff_noirq,
1259 		.restore_noirq = acpi_lpss_restore_noirq,
1260 		.restore_early = acpi_lpss_restore_early,
1261 #endif
1262 		.runtime_suspend = acpi_lpss_runtime_suspend,
1263 		.runtime_resume = acpi_lpss_runtime_resume,
1264 #endif
1265 	},
1266 };
1267 
1268 static int acpi_lpss_platform_notify(struct notifier_block *nb,
1269 				     unsigned long action, void *data)
1270 {
1271 	struct platform_device *pdev = to_platform_device(data);
1272 	struct lpss_private_data *pdata;
1273 	struct acpi_device *adev;
1274 	const struct acpi_device_id *id;
1275 
1276 	id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
1277 	if (!id || !id->driver_data)
1278 		return 0;
1279 
1280 	adev = ACPI_COMPANION(&pdev->dev);
1281 	if (!adev)
1282 		return 0;
1283 
1284 	pdata = acpi_driver_data(adev);
1285 	if (!pdata)
1286 		return 0;
1287 
1288 	if (pdata->mmio_base &&
1289 	    pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
1290 		dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
1291 		return 0;
1292 	}
1293 
1294 	switch (action) {
1295 	case BUS_NOTIFY_BIND_DRIVER:
1296 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1297 		break;
1298 	case BUS_NOTIFY_DRIVER_NOT_BOUND:
1299 	case BUS_NOTIFY_UNBOUND_DRIVER:
1300 		dev_pm_domain_set(&pdev->dev, NULL);
1301 		break;
1302 	case BUS_NOTIFY_ADD_DEVICE:
1303 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1304 		if (pdata->dev_desc->flags & LPSS_LTR)
1305 			return sysfs_create_group(&pdev->dev.kobj,
1306 						  &lpss_attr_group);
1307 		break;
1308 	case BUS_NOTIFY_DEL_DEVICE:
1309 		if (pdata->dev_desc->flags & LPSS_LTR)
1310 			sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
1311 		dev_pm_domain_set(&pdev->dev, NULL);
1312 		break;
1313 	default:
1314 		break;
1315 	}
1316 
1317 	return 0;
1318 }
1319 
1320 static struct notifier_block acpi_lpss_nb = {
1321 	.notifier_call = acpi_lpss_platform_notify,
1322 };
1323 
1324 static void acpi_lpss_bind(struct device *dev)
1325 {
1326 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1327 
1328 	if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
1329 		return;
1330 
1331 	if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
1332 		dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
1333 	else
1334 		dev_err(dev, "MMIO size insufficient to access LTR\n");
1335 }
1336 
1337 static void acpi_lpss_unbind(struct device *dev)
1338 {
1339 	dev->power.set_latency_tolerance = NULL;
1340 }
1341 
1342 static struct acpi_scan_handler lpss_handler = {
1343 	.ids = acpi_lpss_device_ids,
1344 	.attach = acpi_lpss_create_device,
1345 	.bind = acpi_lpss_bind,
1346 	.unbind = acpi_lpss_unbind,
1347 };
1348 
1349 void __init acpi_lpss_init(void)
1350 {
1351 	const struct x86_cpu_id *id;
1352 	int ret;
1353 
1354 	ret = lpss_atom_clk_init();
1355 	if (ret)
1356 		return;
1357 
1358 	id = x86_match_cpu(lpss_cpu_ids);
1359 	if (id)
1360 		lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;
1361 
1362 	bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
1363 	acpi_scan_add_handler(&lpss_handler);
1364 }
1365 
1366 #else
1367 
1368 static struct acpi_scan_handler lpss_handler = {
1369 	.ids = acpi_lpss_device_ids,
1370 };
1371 
1372 void __init acpi_lpss_init(void)
1373 {
1374 	acpi_scan_add_handler(&lpss_handler);
1375 }
1376 
1377 #endif /* CONFIG_X86_INTEL_LPSS */
1378