xref: /openbmc/linux/drivers/acpi/acpi_lpss.c (revision 4b33b5ff)
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 	struct acpi_device *adev = pdata->adev;
171 
172 	/* Only call pwm_add_table for the first PWM controller */
173 	if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "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 	const char *uid_str = acpi_device_uid(pdata->adev);
184 	acpi_handle handle = pdata->adev->handle;
185 	unsigned long long shared_host = 0;
186 	acpi_status status;
187 	long uid = 0;
188 
189 	/* Expected to always be true, but better safe then sorry */
190 	if (uid_str && !kstrtol(uid_str, 10, &uid) && uid) {
191 		/* Detect I2C bus shared with PUNIT and ignore its d3 status */
192 		status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host);
193 		if (ACPI_SUCCESS(status) && shared_host)
194 			pmc_atom_d3_mask &= ~(BIT_LPSS2_F1_I2C1 << (uid - 1));
195 	}
196 
197 	lpss_deassert_reset(pdata);
198 
199 	if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset))
200 		pdata->fixed_clk_rate = 133000000;
201 
202 	writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
203 }
204 
205 /* BSW PWM used for backlight control by the i915 driver */
206 static struct pwm_lookup bsw_pwm_lookup[] = {
207 	PWM_LOOKUP_WITH_MODULE("80862288:00", 0, "0000:00:02.0",
208 			       "pwm_soc_backlight", 0, PWM_POLARITY_NORMAL,
209 			       "pwm-lpss-platform"),
210 };
211 
212 static void bsw_pwm_setup(struct lpss_private_data *pdata)
213 {
214 	struct acpi_device *adev = pdata->adev;
215 
216 	/* Only call pwm_add_table for the first PWM controller */
217 	if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "1"))
218 		return;
219 
220 	pwm_add_table(bsw_pwm_lookup, ARRAY_SIZE(bsw_pwm_lookup));
221 }
222 
223 static const struct property_entry lpt_spi_properties[] = {
224 	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_LPT_SSP),
225 	{ }
226 };
227 
228 static const struct lpss_device_desc lpt_spi_dev_desc = {
229 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR
230 			| LPSS_SAVE_CTX,
231 	.prv_offset = 0x800,
232 	.properties = lpt_spi_properties,
233 };
234 
235 static const struct lpss_device_desc lpt_i2c_dev_desc = {
236 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR | LPSS_SAVE_CTX,
237 	.prv_offset = 0x800,
238 };
239 
240 static struct property_entry uart_properties[] = {
241 	PROPERTY_ENTRY_U32("reg-io-width", 4),
242 	PROPERTY_ENTRY_U32("reg-shift", 2),
243 	PROPERTY_ENTRY_BOOL("snps,uart-16550-compatible"),
244 	{ },
245 };
246 
247 static const struct lpss_device_desc lpt_uart_dev_desc = {
248 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR
249 			| LPSS_SAVE_CTX,
250 	.clk_con_id = "baudclk",
251 	.prv_offset = 0x800,
252 	.setup = lpss_uart_setup,
253 	.properties = uart_properties,
254 };
255 
256 static const struct lpss_device_desc lpt_sdio_dev_desc = {
257 	.flags = LPSS_LTR,
258 	.prv_offset = 0x1000,
259 	.prv_size_override = 0x1018,
260 };
261 
262 static const struct lpss_device_desc byt_pwm_dev_desc = {
263 	.flags = LPSS_SAVE_CTX,
264 	.prv_offset = 0x800,
265 	.setup = byt_pwm_setup,
266 };
267 
268 static const struct lpss_device_desc bsw_pwm_dev_desc = {
269 	.flags = LPSS_SAVE_CTX_ONCE | LPSS_NO_D3_DELAY,
270 	.prv_offset = 0x800,
271 	.setup = bsw_pwm_setup,
272 	.resume_from_noirq = true,
273 };
274 
275 static const struct lpss_device_desc byt_uart_dev_desc = {
276 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
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 bsw_uart_dev_desc = {
284 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
285 			| LPSS_NO_D3_DELAY,
286 	.clk_con_id = "baudclk",
287 	.prv_offset = 0x800,
288 	.setup = lpss_uart_setup,
289 	.properties = uart_properties,
290 };
291 
292 static const struct property_entry byt_spi_properties[] = {
293 	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_BYT_SSP),
294 	{ }
295 };
296 
297 static const struct lpss_device_desc byt_spi_dev_desc = {
298 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
299 	.prv_offset = 0x400,
300 	.properties = byt_spi_properties,
301 };
302 
303 static const struct lpss_device_desc byt_sdio_dev_desc = {
304 	.flags = LPSS_CLK,
305 };
306 
307 static const struct lpss_device_desc byt_i2c_dev_desc = {
308 	.flags = LPSS_CLK | LPSS_SAVE_CTX,
309 	.prv_offset = 0x800,
310 	.setup = byt_i2c_setup,
311 	.resume_from_noirq = true,
312 };
313 
314 static const struct lpss_device_desc bsw_i2c_dev_desc = {
315 	.flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
316 	.prv_offset = 0x800,
317 	.setup = byt_i2c_setup,
318 	.resume_from_noirq = true,
319 };
320 
321 static const struct property_entry bsw_spi_properties[] = {
322 	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_BSW_SSP),
323 	{ }
324 };
325 
326 static const struct lpss_device_desc bsw_spi_dev_desc = {
327 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
328 			| LPSS_NO_D3_DELAY,
329 	.prv_offset = 0x400,
330 	.setup = lpss_deassert_reset,
331 	.properties = bsw_spi_properties,
332 };
333 
334 static const struct x86_cpu_id lpss_cpu_ids[] = {
335 	X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT,	NULL),
336 	X86_MATCH_INTEL_FAM6_MODEL(ATOM_AIRMONT,	NULL),
337 	{}
338 };
339 
340 #else
341 
342 #define LPSS_ADDR(desc) (0UL)
343 
344 #endif /* CONFIG_X86_INTEL_LPSS */
345 
346 static const struct acpi_device_id acpi_lpss_device_ids[] = {
347 	/* Generic LPSS devices */
348 	{ "INTL9C60", LPSS_ADDR(lpss_dma_desc) },
349 
350 	/* Lynxpoint LPSS devices */
351 	{ "INT33C0", LPSS_ADDR(lpt_spi_dev_desc) },
352 	{ "INT33C1", LPSS_ADDR(lpt_spi_dev_desc) },
353 	{ "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },
354 	{ "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },
355 	{ "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },
356 	{ "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },
357 	{ "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },
358 	{ "INT33C7", },
359 
360 	/* BayTrail LPSS devices */
361 	{ "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },
362 	{ "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },
363 	{ "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },
364 	{ "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },
365 	{ "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },
366 	{ "INT33B2", },
367 	{ "INT33FC", },
368 
369 	/* Braswell LPSS devices */
370 	{ "80862286", LPSS_ADDR(lpss_dma_desc) },
371 	{ "80862288", LPSS_ADDR(bsw_pwm_dev_desc) },
372 	{ "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },
373 	{ "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },
374 	{ "808622C0", LPSS_ADDR(lpss_dma_desc) },
375 	{ "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) },
376 
377 	/* Broadwell LPSS devices */
378 	{ "INT3430", LPSS_ADDR(lpt_spi_dev_desc) },
379 	{ "INT3431", LPSS_ADDR(lpt_spi_dev_desc) },
380 	{ "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },
381 	{ "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },
382 	{ "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },
383 	{ "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },
384 	{ "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },
385 	{ "INT3437", },
386 
387 	/* Wildcat Point LPSS devices */
388 	{ "INT3438", LPSS_ADDR(lpt_spi_dev_desc) },
389 
390 	{ }
391 };
392 
393 #ifdef CONFIG_X86_INTEL_LPSS
394 
395 static int is_memory(struct acpi_resource *res, void *not_used)
396 {
397 	struct resource r;
398 
399 	return !acpi_dev_resource_memory(res, &r);
400 }
401 
402 /* LPSS main clock device. */
403 static struct platform_device *lpss_clk_dev;
404 
405 static inline void lpt_register_clock_device(void)
406 {
407 	lpss_clk_dev = platform_device_register_simple("clk-lpss-atom",
408 						       PLATFORM_DEVID_NONE,
409 						       NULL, 0);
410 }
411 
412 static int register_device_clock(struct acpi_device *adev,
413 				 struct lpss_private_data *pdata)
414 {
415 	const struct lpss_device_desc *dev_desc = pdata->dev_desc;
416 	const char *devname = dev_name(&adev->dev);
417 	struct clk *clk;
418 	struct lpss_clk_data *clk_data;
419 	const char *parent, *clk_name;
420 	void __iomem *prv_base;
421 
422 	if (!lpss_clk_dev)
423 		lpt_register_clock_device();
424 
425 	clk_data = platform_get_drvdata(lpss_clk_dev);
426 	if (!clk_data)
427 		return -ENODEV;
428 	clk = clk_data->clk;
429 
430 	if (!pdata->mmio_base
431 	    || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
432 		return -ENODATA;
433 
434 	parent = clk_data->name;
435 	prv_base = pdata->mmio_base + dev_desc->prv_offset;
436 
437 	if (pdata->fixed_clk_rate) {
438 		clk = clk_register_fixed_rate(NULL, devname, parent, 0,
439 					      pdata->fixed_clk_rate);
440 		goto out;
441 	}
442 
443 	if (dev_desc->flags & LPSS_CLK_GATE) {
444 		clk = clk_register_gate(NULL, devname, parent, 0,
445 					prv_base, 0, 0, NULL);
446 		parent = devname;
447 	}
448 
449 	if (dev_desc->flags & LPSS_CLK_DIVIDER) {
450 		/* Prevent division by zero */
451 		if (!readl(prv_base))
452 			writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
453 
454 		clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
455 		if (!clk_name)
456 			return -ENOMEM;
457 		clk = clk_register_fractional_divider(NULL, clk_name, parent,
458 						      CLK_FRAC_DIVIDER_POWER_OF_TWO_PS,
459 						      prv_base, 1, 15, 16, 15, 0, NULL);
460 		parent = clk_name;
461 
462 		clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
463 		if (!clk_name) {
464 			kfree(parent);
465 			return -ENOMEM;
466 		}
467 		clk = clk_register_gate(NULL, clk_name, parent,
468 					CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
469 					prv_base, 31, 0, NULL);
470 		kfree(parent);
471 		kfree(clk_name);
472 	}
473 out:
474 	if (IS_ERR(clk))
475 		return PTR_ERR(clk);
476 
477 	pdata->clk = clk;
478 	clk_register_clkdev(clk, dev_desc->clk_con_id, devname);
479 	return 0;
480 }
481 
482 struct lpss_device_links {
483 	const char *supplier_hid;
484 	const char *supplier_uid;
485 	const char *consumer_hid;
486 	const char *consumer_uid;
487 	u32 flags;
488 	const struct dmi_system_id *dep_missing_ids;
489 };
490 
491 /* Please keep this list sorted alphabetically by vendor and model */
492 static const struct dmi_system_id i2c1_dep_missing_dmi_ids[] = {
493 	{
494 		.matches = {
495 			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
496 			DMI_MATCH(DMI_PRODUCT_NAME, "T200TA"),
497 		},
498 	},
499 	{}
500 };
501 
502 /*
503  * The _DEP method is used to identify dependencies but instead of creating
504  * device links for every handle in _DEP, only links in the following list are
505  * created. That is necessary because, in the general case, _DEP can refer to
506  * devices that might not have drivers, or that are on different buses, or where
507  * the supplier is not enumerated until after the consumer is probed.
508  */
509 static const struct lpss_device_links lpss_device_links[] = {
510 	/* CHT External sdcard slot controller depends on PMIC I2C ctrl */
511 	{"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME},
512 	/* CHT iGPU depends on PMIC I2C controller */
513 	{"808622C1", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
514 	/* BYT iGPU depends on the Embedded Controller I2C controller (UID 1) */
515 	{"80860F41", "1", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME,
516 	 i2c1_dep_missing_dmi_ids},
517 	/* BYT CR iGPU depends on PMIC I2C controller (UID 5 on CR) */
518 	{"80860F41", "5", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
519 	/* BYT iGPU depends on PMIC I2C controller (UID 7 on non CR) */
520 	{"80860F41", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
521 };
522 
523 static bool acpi_lpss_is_supplier(struct acpi_device *adev,
524 				  const struct lpss_device_links *link)
525 {
526 	return acpi_dev_hid_uid_match(adev, link->supplier_hid, link->supplier_uid);
527 }
528 
529 static bool acpi_lpss_is_consumer(struct acpi_device *adev,
530 				  const struct lpss_device_links *link)
531 {
532 	return acpi_dev_hid_uid_match(adev, link->consumer_hid, link->consumer_uid);
533 }
534 
535 struct hid_uid {
536 	const char *hid;
537 	const char *uid;
538 };
539 
540 static int match_hid_uid(struct device *dev, const void *data)
541 {
542 	struct acpi_device *adev = ACPI_COMPANION(dev);
543 	const struct hid_uid *id = data;
544 
545 	if (!adev)
546 		return 0;
547 
548 	return acpi_dev_hid_uid_match(adev, id->hid, id->uid);
549 }
550 
551 static struct device *acpi_lpss_find_device(const char *hid, const char *uid)
552 {
553 	struct device *dev;
554 
555 	struct hid_uid data = {
556 		.hid = hid,
557 		.uid = uid,
558 	};
559 
560 	dev = bus_find_device(&platform_bus_type, NULL, &data, match_hid_uid);
561 	if (dev)
562 		return dev;
563 
564 	return bus_find_device(&pci_bus_type, NULL, &data, match_hid_uid);
565 }
566 
567 static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle)
568 {
569 	struct acpi_handle_list dep_devices;
570 	acpi_status status;
571 	int i;
572 
573 	if (!acpi_has_method(adev->handle, "_DEP"))
574 		return false;
575 
576 	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
577 					 &dep_devices);
578 	if (ACPI_FAILURE(status)) {
579 		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
580 		return false;
581 	}
582 
583 	for (i = 0; i < dep_devices.count; i++) {
584 		if (dep_devices.handles[i] == handle)
585 			return true;
586 	}
587 
588 	return false;
589 }
590 
591 static void acpi_lpss_link_consumer(struct device *dev1,
592 				    const struct lpss_device_links *link)
593 {
594 	struct device *dev2;
595 
596 	dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid);
597 	if (!dev2)
598 		return;
599 
600 	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
601 	    || acpi_lpss_dep(ACPI_COMPANION(dev2), ACPI_HANDLE(dev1)))
602 		device_link_add(dev2, dev1, link->flags);
603 
604 	put_device(dev2);
605 }
606 
607 static void acpi_lpss_link_supplier(struct device *dev1,
608 				    const struct lpss_device_links *link)
609 {
610 	struct device *dev2;
611 
612 	dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid);
613 	if (!dev2)
614 		return;
615 
616 	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
617 	    || acpi_lpss_dep(ACPI_COMPANION(dev1), ACPI_HANDLE(dev2)))
618 		device_link_add(dev1, dev2, link->flags);
619 
620 	put_device(dev2);
621 }
622 
623 static void acpi_lpss_create_device_links(struct acpi_device *adev,
624 					  struct platform_device *pdev)
625 {
626 	int i;
627 
628 	for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) {
629 		const struct lpss_device_links *link = &lpss_device_links[i];
630 
631 		if (acpi_lpss_is_supplier(adev, link))
632 			acpi_lpss_link_consumer(&pdev->dev, link);
633 
634 		if (acpi_lpss_is_consumer(adev, link))
635 			acpi_lpss_link_supplier(&pdev->dev, link);
636 	}
637 }
638 
639 static int acpi_lpss_create_device(struct acpi_device *adev,
640 				   const struct acpi_device_id *id)
641 {
642 	const struct lpss_device_desc *dev_desc;
643 	struct lpss_private_data *pdata;
644 	struct resource_entry *rentry;
645 	struct list_head resource_list;
646 	struct platform_device *pdev;
647 	int ret;
648 
649 	dev_desc = (const struct lpss_device_desc *)id->driver_data;
650 	if (!dev_desc) {
651 		pdev = acpi_create_platform_device(adev, NULL);
652 		return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
653 	}
654 	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
655 	if (!pdata)
656 		return -ENOMEM;
657 
658 	INIT_LIST_HEAD(&resource_list);
659 	ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL);
660 	if (ret < 0)
661 		goto err_out;
662 
663 	list_for_each_entry(rentry, &resource_list, node)
664 		if (resource_type(rentry->res) == IORESOURCE_MEM) {
665 			if (dev_desc->prv_size_override)
666 				pdata->mmio_size = dev_desc->prv_size_override;
667 			else
668 				pdata->mmio_size = resource_size(rentry->res);
669 			pdata->mmio_base = ioremap(rentry->res->start,
670 						   pdata->mmio_size);
671 			break;
672 		}
673 
674 	acpi_dev_free_resource_list(&resource_list);
675 
676 	if (!pdata->mmio_base) {
677 		/* Avoid acpi_bus_attach() instantiating a pdev for this dev. */
678 		adev->pnp.type.platform_id = 0;
679 		/* Skip the device, but continue the namespace scan. */
680 		ret = 0;
681 		goto err_out;
682 	}
683 
684 	pdata->adev = adev;
685 	pdata->dev_desc = dev_desc;
686 
687 	if (dev_desc->setup)
688 		dev_desc->setup(pdata);
689 
690 	if (dev_desc->flags & LPSS_CLK) {
691 		ret = register_device_clock(adev, pdata);
692 		if (ret) {
693 			/* Skip the device, but continue the namespace scan. */
694 			ret = 0;
695 			goto err_out;
696 		}
697 	}
698 
699 	/*
700 	 * This works around a known issue in ACPI tables where LPSS devices
701 	 * have _PS0 and _PS3 without _PSC (and no power resources), so
702 	 * acpi_bus_init_power() will assume that the BIOS has put them into D0.
703 	 */
704 	acpi_device_fix_up_power(adev);
705 
706 	adev->driver_data = pdata;
707 	pdev = acpi_create_platform_device(adev, dev_desc->properties);
708 	if (!IS_ERR_OR_NULL(pdev)) {
709 		acpi_lpss_create_device_links(adev, pdev);
710 		return 1;
711 	}
712 
713 	ret = PTR_ERR(pdev);
714 	adev->driver_data = NULL;
715 
716  err_out:
717 	kfree(pdata);
718 	return ret;
719 }
720 
721 static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
722 {
723 	return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
724 }
725 
726 static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
727 			     unsigned int reg)
728 {
729 	writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
730 }
731 
732 static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
733 {
734 	struct acpi_device *adev = ACPI_COMPANION(dev);
735 	struct lpss_private_data *pdata;
736 	unsigned long flags;
737 	int ret;
738 
739 	if (WARN_ON(!adev))
740 		return -ENODEV;
741 
742 	spin_lock_irqsave(&dev->power.lock, flags);
743 	if (pm_runtime_suspended(dev)) {
744 		ret = -EAGAIN;
745 		goto out;
746 	}
747 	pdata = acpi_driver_data(adev);
748 	if (WARN_ON(!pdata || !pdata->mmio_base)) {
749 		ret = -ENODEV;
750 		goto out;
751 	}
752 	*val = __lpss_reg_read(pdata, reg);
753 	ret = 0;
754 
755  out:
756 	spin_unlock_irqrestore(&dev->power.lock, flags);
757 	return ret;
758 }
759 
760 static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
761 			     char *buf)
762 {
763 	u32 ltr_value = 0;
764 	unsigned int reg;
765 	int ret;
766 
767 	reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
768 	ret = lpss_reg_read(dev, reg, &ltr_value);
769 	if (ret)
770 		return ret;
771 
772 	return sysfs_emit(buf, "%08x\n", ltr_value);
773 }
774 
775 static ssize_t lpss_ltr_mode_show(struct device *dev,
776 				  struct device_attribute *attr, char *buf)
777 {
778 	u32 ltr_mode = 0;
779 	char *outstr;
780 	int ret;
781 
782 	ret = lpss_reg_read(dev, LPSS_GENERAL, &ltr_mode);
783 	if (ret)
784 		return ret;
785 
786 	outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
787 	return sprintf(buf, "%s\n", outstr);
788 }
789 
790 static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
791 static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
792 static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
793 
794 static struct attribute *lpss_attrs[] = {
795 	&dev_attr_auto_ltr.attr,
796 	&dev_attr_sw_ltr.attr,
797 	&dev_attr_ltr_mode.attr,
798 	NULL,
799 };
800 
801 static const struct attribute_group lpss_attr_group = {
802 	.attrs = lpss_attrs,
803 	.name = "lpss_ltr",
804 };
805 
806 static void acpi_lpss_set_ltr(struct device *dev, s32 val)
807 {
808 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
809 	u32 ltr_mode, ltr_val;
810 
811 	ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
812 	if (val < 0) {
813 		if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
814 			ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
815 			__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
816 		}
817 		return;
818 	}
819 	ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
820 	if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
821 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
822 		val = LPSS_LTR_MAX_VAL;
823 	} else if (val > LPSS_LTR_MAX_VAL) {
824 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
825 		val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
826 	} else {
827 		ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
828 	}
829 	ltr_val |= val;
830 	__lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
831 	if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
832 		ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
833 		__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
834 	}
835 }
836 
837 #ifdef CONFIG_PM
838 /**
839  * acpi_lpss_save_ctx() - Save the private registers of LPSS device
840  * @dev: LPSS device
841  * @pdata: pointer to the private data of the LPSS device
842  *
843  * Most LPSS devices have private registers which may loose their context when
844  * the device is powered down. acpi_lpss_save_ctx() saves those registers into
845  * prv_reg_ctx array.
846  */
847 static void acpi_lpss_save_ctx(struct device *dev,
848 			       struct lpss_private_data *pdata)
849 {
850 	unsigned int i;
851 
852 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
853 		unsigned long offset = i * sizeof(u32);
854 
855 		pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
856 		dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
857 			pdata->prv_reg_ctx[i], offset);
858 	}
859 }
860 
861 /**
862  * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
863  * @dev: LPSS device
864  * @pdata: pointer to the private data of the LPSS device
865  *
866  * Restores the registers that were previously stored with acpi_lpss_save_ctx().
867  */
868 static void acpi_lpss_restore_ctx(struct device *dev,
869 				  struct lpss_private_data *pdata)
870 {
871 	unsigned int i;
872 
873 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
874 		unsigned long offset = i * sizeof(u32);
875 
876 		__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
877 		dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
878 			pdata->prv_reg_ctx[i], offset);
879 	}
880 }
881 
882 static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
883 {
884 	/*
885 	 * The following delay is needed or the subsequent write operations may
886 	 * fail. The LPSS devices are actually PCI devices and the PCI spec
887 	 * expects 10ms delay before the device can be accessed after D3 to D0
888 	 * transition. However some platforms like BSW does not need this delay.
889 	 */
890 	unsigned int delay = 10;	/* default 10ms delay */
891 
892 	if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)
893 		delay = 0;
894 
895 	msleep(delay);
896 }
897 
898 static int acpi_lpss_activate(struct device *dev)
899 {
900 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
901 	int ret;
902 
903 	ret = acpi_dev_resume(dev);
904 	if (ret)
905 		return ret;
906 
907 	acpi_lpss_d3_to_d0_delay(pdata);
908 
909 	/*
910 	 * This is called only on ->probe() stage where a device is either in
911 	 * known state defined by BIOS or most likely powered off. Due to this
912 	 * we have to deassert reset line to be sure that ->probe() will
913 	 * recognize the device.
914 	 */
915 	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
916 		lpss_deassert_reset(pdata);
917 
918 #ifdef CONFIG_PM
919 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX_ONCE)
920 		acpi_lpss_save_ctx(dev, pdata);
921 #endif
922 
923 	return 0;
924 }
925 
926 static void acpi_lpss_dismiss(struct device *dev)
927 {
928 	acpi_dev_suspend(dev, false);
929 }
930 
931 /* IOSF SB for LPSS island */
932 #define LPSS_IOSF_UNIT_LPIOEP		0xA0
933 #define LPSS_IOSF_UNIT_LPIO1		0xAB
934 #define LPSS_IOSF_UNIT_LPIO2		0xAC
935 
936 #define LPSS_IOSF_PMCSR			0x84
937 #define LPSS_PMCSR_D0			0
938 #define LPSS_PMCSR_D3hot		3
939 #define LPSS_PMCSR_Dx_MASK		GENMASK(1, 0)
940 
941 #define LPSS_IOSF_GPIODEF0		0x154
942 #define LPSS_GPIODEF0_DMA1_D3		BIT(2)
943 #define LPSS_GPIODEF0_DMA2_D3		BIT(3)
944 #define LPSS_GPIODEF0_DMA_D3_MASK	GENMASK(3, 2)
945 #define LPSS_GPIODEF0_DMA_LLP		BIT(13)
946 
947 static DEFINE_MUTEX(lpss_iosf_mutex);
948 static bool lpss_iosf_d3_entered = true;
949 
950 static void lpss_iosf_enter_d3_state(void)
951 {
952 	u32 value1 = 0;
953 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
954 	u32 value2 = LPSS_PMCSR_D3hot;
955 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
956 	/*
957 	 * PMC provides an information about actual status of the LPSS devices.
958 	 * Here we read the values related to LPSS power island, i.e. LPSS
959 	 * devices, excluding both LPSS DMA controllers, along with SCC domain.
960 	 */
961 	u32 func_dis, d3_sts_0, pmc_status;
962 	int ret;
963 
964 	ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);
965 	if (ret)
966 		return;
967 
968 	mutex_lock(&lpss_iosf_mutex);
969 
970 	ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);
971 	if (ret)
972 		goto exit;
973 
974 	/*
975 	 * Get the status of entire LPSS power island per device basis.
976 	 * Shutdown both LPSS DMA controllers if and only if all other devices
977 	 * are already in D3hot.
978 	 */
979 	pmc_status = (~(d3_sts_0 | func_dis)) & pmc_atom_d3_mask;
980 	if (pmc_status)
981 		goto exit;
982 
983 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
984 			LPSS_IOSF_PMCSR, value2, mask2);
985 
986 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
987 			LPSS_IOSF_PMCSR, value2, mask2);
988 
989 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
990 			LPSS_IOSF_GPIODEF0, value1, mask1);
991 
992 	lpss_iosf_d3_entered = true;
993 
994 exit:
995 	mutex_unlock(&lpss_iosf_mutex);
996 }
997 
998 static void lpss_iosf_exit_d3_state(void)
999 {
1000 	u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 |
1001 		     LPSS_GPIODEF0_DMA_LLP;
1002 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
1003 	u32 value2 = LPSS_PMCSR_D0;
1004 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
1005 
1006 	mutex_lock(&lpss_iosf_mutex);
1007 
1008 	if (!lpss_iosf_d3_entered)
1009 		goto exit;
1010 
1011 	lpss_iosf_d3_entered = false;
1012 
1013 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
1014 			LPSS_IOSF_GPIODEF0, value1, mask1);
1015 
1016 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
1017 			LPSS_IOSF_PMCSR, value2, mask2);
1018 
1019 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
1020 			LPSS_IOSF_PMCSR, value2, mask2);
1021 
1022 exit:
1023 	mutex_unlock(&lpss_iosf_mutex);
1024 }
1025 
1026 static int acpi_lpss_suspend(struct device *dev, bool wakeup)
1027 {
1028 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1029 	int ret;
1030 
1031 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
1032 		acpi_lpss_save_ctx(dev, pdata);
1033 
1034 	ret = acpi_dev_suspend(dev, wakeup);
1035 
1036 	/*
1037 	 * This call must be last in the sequence, otherwise PMC will return
1038 	 * wrong status for devices being about to be powered off. See
1039 	 * lpss_iosf_enter_d3_state() for further information.
1040 	 */
1041 	if (acpi_target_system_state() == ACPI_STATE_S0 &&
1042 	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1043 		lpss_iosf_enter_d3_state();
1044 
1045 	return ret;
1046 }
1047 
1048 static int acpi_lpss_resume(struct device *dev)
1049 {
1050 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1051 	int ret;
1052 
1053 	/*
1054 	 * This call is kept first to be in symmetry with
1055 	 * acpi_lpss_runtime_suspend() one.
1056 	 */
1057 	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1058 		lpss_iosf_exit_d3_state();
1059 
1060 	ret = acpi_dev_resume(dev);
1061 	if (ret)
1062 		return ret;
1063 
1064 	acpi_lpss_d3_to_d0_delay(pdata);
1065 
1066 	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
1067 		acpi_lpss_restore_ctx(dev, pdata);
1068 
1069 	return 0;
1070 }
1071 
1072 #ifdef CONFIG_PM_SLEEP
1073 static int acpi_lpss_do_suspend_late(struct device *dev)
1074 {
1075 	int ret;
1076 
1077 	if (dev_pm_skip_suspend(dev))
1078 		return 0;
1079 
1080 	ret = pm_generic_suspend_late(dev);
1081 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1082 }
1083 
1084 static int acpi_lpss_suspend_late(struct device *dev)
1085 {
1086 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1087 
1088 	if (pdata->dev_desc->resume_from_noirq)
1089 		return 0;
1090 
1091 	return acpi_lpss_do_suspend_late(dev);
1092 }
1093 
1094 static int acpi_lpss_suspend_noirq(struct device *dev)
1095 {
1096 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1097 	int ret;
1098 
1099 	if (pdata->dev_desc->resume_from_noirq) {
1100 		/*
1101 		 * The driver's ->suspend_late callback will be invoked by
1102 		 * acpi_lpss_do_suspend_late(), with the assumption that the
1103 		 * driver really wanted to run that code in ->suspend_noirq, but
1104 		 * it could not run after acpi_dev_suspend() and the driver
1105 		 * expected the latter to be called in the "late" phase.
1106 		 */
1107 		ret = acpi_lpss_do_suspend_late(dev);
1108 		if (ret)
1109 			return ret;
1110 	}
1111 
1112 	return acpi_subsys_suspend_noirq(dev);
1113 }
1114 
1115 static int acpi_lpss_do_resume_early(struct device *dev)
1116 {
1117 	int ret = acpi_lpss_resume(dev);
1118 
1119 	return ret ? ret : pm_generic_resume_early(dev);
1120 }
1121 
1122 static int acpi_lpss_resume_early(struct device *dev)
1123 {
1124 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1125 
1126 	if (pdata->dev_desc->resume_from_noirq)
1127 		return 0;
1128 
1129 	if (dev_pm_skip_resume(dev))
1130 		return 0;
1131 
1132 	return acpi_lpss_do_resume_early(dev);
1133 }
1134 
1135 static int acpi_lpss_resume_noirq(struct device *dev)
1136 {
1137 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1138 	int ret;
1139 
1140 	/* Follow acpi_subsys_resume_noirq(). */
1141 	if (dev_pm_skip_resume(dev))
1142 		return 0;
1143 
1144 	ret = pm_generic_resume_noirq(dev);
1145 	if (ret)
1146 		return ret;
1147 
1148 	if (!pdata->dev_desc->resume_from_noirq)
1149 		return 0;
1150 
1151 	/*
1152 	 * The driver's ->resume_early callback will be invoked by
1153 	 * acpi_lpss_do_resume_early(), with the assumption that the driver
1154 	 * really wanted to run that code in ->resume_noirq, but it could not
1155 	 * run before acpi_dev_resume() and the driver expected the latter to be
1156 	 * called in the "early" phase.
1157 	 */
1158 	return acpi_lpss_do_resume_early(dev);
1159 }
1160 
1161 static int acpi_lpss_do_restore_early(struct device *dev)
1162 {
1163 	int ret = acpi_lpss_resume(dev);
1164 
1165 	return ret ? ret : pm_generic_restore_early(dev);
1166 }
1167 
1168 static int acpi_lpss_restore_early(struct device *dev)
1169 {
1170 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1171 
1172 	if (pdata->dev_desc->resume_from_noirq)
1173 		return 0;
1174 
1175 	return acpi_lpss_do_restore_early(dev);
1176 }
1177 
1178 static int acpi_lpss_restore_noirq(struct device *dev)
1179 {
1180 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1181 	int ret;
1182 
1183 	ret = pm_generic_restore_noirq(dev);
1184 	if (ret)
1185 		return ret;
1186 
1187 	if (!pdata->dev_desc->resume_from_noirq)
1188 		return 0;
1189 
1190 	/* This is analogous to what happens in acpi_lpss_resume_noirq(). */
1191 	return acpi_lpss_do_restore_early(dev);
1192 }
1193 
1194 static int acpi_lpss_do_poweroff_late(struct device *dev)
1195 {
1196 	int ret = pm_generic_poweroff_late(dev);
1197 
1198 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1199 }
1200 
1201 static int acpi_lpss_poweroff_late(struct device *dev)
1202 {
1203 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1204 
1205 	if (dev_pm_skip_suspend(dev))
1206 		return 0;
1207 
1208 	if (pdata->dev_desc->resume_from_noirq)
1209 		return 0;
1210 
1211 	return acpi_lpss_do_poweroff_late(dev);
1212 }
1213 
1214 static int acpi_lpss_poweroff_noirq(struct device *dev)
1215 {
1216 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1217 
1218 	if (dev_pm_skip_suspend(dev))
1219 		return 0;
1220 
1221 	if (pdata->dev_desc->resume_from_noirq) {
1222 		/* This is analogous to the acpi_lpss_suspend_noirq() case. */
1223 		int ret = acpi_lpss_do_poweroff_late(dev);
1224 
1225 		if (ret)
1226 			return ret;
1227 	}
1228 
1229 	return pm_generic_poweroff_noirq(dev);
1230 }
1231 #endif /* CONFIG_PM_SLEEP */
1232 
1233 static int acpi_lpss_runtime_suspend(struct device *dev)
1234 {
1235 	int ret = pm_generic_runtime_suspend(dev);
1236 
1237 	return ret ? ret : acpi_lpss_suspend(dev, true);
1238 }
1239 
1240 static int acpi_lpss_runtime_resume(struct device *dev)
1241 {
1242 	int ret = acpi_lpss_resume(dev);
1243 
1244 	return ret ? ret : pm_generic_runtime_resume(dev);
1245 }
1246 #endif /* CONFIG_PM */
1247 
1248 static struct dev_pm_domain acpi_lpss_pm_domain = {
1249 #ifdef CONFIG_PM
1250 	.activate = acpi_lpss_activate,
1251 	.dismiss = acpi_lpss_dismiss,
1252 #endif
1253 	.ops = {
1254 #ifdef CONFIG_PM
1255 #ifdef CONFIG_PM_SLEEP
1256 		.prepare = acpi_subsys_prepare,
1257 		.complete = acpi_subsys_complete,
1258 		.suspend = acpi_subsys_suspend,
1259 		.suspend_late = acpi_lpss_suspend_late,
1260 		.suspend_noirq = acpi_lpss_suspend_noirq,
1261 		.resume_noirq = acpi_lpss_resume_noirq,
1262 		.resume_early = acpi_lpss_resume_early,
1263 		.freeze = acpi_subsys_freeze,
1264 		.poweroff = acpi_subsys_poweroff,
1265 		.poweroff_late = acpi_lpss_poweroff_late,
1266 		.poweroff_noirq = acpi_lpss_poweroff_noirq,
1267 		.restore_noirq = acpi_lpss_restore_noirq,
1268 		.restore_early = acpi_lpss_restore_early,
1269 #endif
1270 		.runtime_suspend = acpi_lpss_runtime_suspend,
1271 		.runtime_resume = acpi_lpss_runtime_resume,
1272 #endif
1273 	},
1274 };
1275 
1276 static int acpi_lpss_platform_notify(struct notifier_block *nb,
1277 				     unsigned long action, void *data)
1278 {
1279 	struct platform_device *pdev = to_platform_device(data);
1280 	struct lpss_private_data *pdata;
1281 	struct acpi_device *adev;
1282 	const struct acpi_device_id *id;
1283 
1284 	id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
1285 	if (!id || !id->driver_data)
1286 		return 0;
1287 
1288 	adev = ACPI_COMPANION(&pdev->dev);
1289 	if (!adev)
1290 		return 0;
1291 
1292 	pdata = acpi_driver_data(adev);
1293 	if (!pdata)
1294 		return 0;
1295 
1296 	if (pdata->mmio_base &&
1297 	    pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
1298 		dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
1299 		return 0;
1300 	}
1301 
1302 	switch (action) {
1303 	case BUS_NOTIFY_BIND_DRIVER:
1304 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1305 		break;
1306 	case BUS_NOTIFY_DRIVER_NOT_BOUND:
1307 	case BUS_NOTIFY_UNBOUND_DRIVER:
1308 		dev_pm_domain_set(&pdev->dev, NULL);
1309 		break;
1310 	case BUS_NOTIFY_ADD_DEVICE:
1311 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1312 		if (pdata->dev_desc->flags & LPSS_LTR)
1313 			return sysfs_create_group(&pdev->dev.kobj,
1314 						  &lpss_attr_group);
1315 		break;
1316 	case BUS_NOTIFY_DEL_DEVICE:
1317 		if (pdata->dev_desc->flags & LPSS_LTR)
1318 			sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
1319 		dev_pm_domain_set(&pdev->dev, NULL);
1320 		break;
1321 	default:
1322 		break;
1323 	}
1324 
1325 	return 0;
1326 }
1327 
1328 static struct notifier_block acpi_lpss_nb = {
1329 	.notifier_call = acpi_lpss_platform_notify,
1330 };
1331 
1332 static void acpi_lpss_bind(struct device *dev)
1333 {
1334 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1335 
1336 	if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
1337 		return;
1338 
1339 	if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
1340 		dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
1341 	else
1342 		dev_err(dev, "MMIO size insufficient to access LTR\n");
1343 }
1344 
1345 static void acpi_lpss_unbind(struct device *dev)
1346 {
1347 	dev->power.set_latency_tolerance = NULL;
1348 }
1349 
1350 static struct acpi_scan_handler lpss_handler = {
1351 	.ids = acpi_lpss_device_ids,
1352 	.attach = acpi_lpss_create_device,
1353 	.bind = acpi_lpss_bind,
1354 	.unbind = acpi_lpss_unbind,
1355 };
1356 
1357 void __init acpi_lpss_init(void)
1358 {
1359 	const struct x86_cpu_id *id;
1360 	int ret;
1361 
1362 	ret = lpss_atom_clk_init();
1363 	if (ret)
1364 		return;
1365 
1366 	id = x86_match_cpu(lpss_cpu_ids);
1367 	if (id)
1368 		lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;
1369 
1370 	bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
1371 	acpi_scan_add_handler(&lpss_handler);
1372 }
1373 
1374 #else
1375 
1376 static struct acpi_scan_handler lpss_handler = {
1377 	.ids = acpi_lpss_device_ids,
1378 };
1379 
1380 void __init acpi_lpss_init(void)
1381 {
1382 	acpi_scan_add_handler(&lpss_handler);
1383 }
1384 
1385 #endif /* CONFIG_X86_INTEL_LPSS */
1386