xref: /openbmc/linux/drivers/acpi/acpi_lpss.c (revision dff03381)
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 	if (IS_ERR(lpss_clk_dev))
426 		return PTR_ERR(lpss_clk_dev);
427 
428 	clk_data = platform_get_drvdata(lpss_clk_dev);
429 	if (!clk_data)
430 		return -ENODEV;
431 	clk = clk_data->clk;
432 
433 	if (!pdata->mmio_base
434 	    || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
435 		return -ENODATA;
436 
437 	parent = clk_data->name;
438 	prv_base = pdata->mmio_base + dev_desc->prv_offset;
439 
440 	if (pdata->fixed_clk_rate) {
441 		clk = clk_register_fixed_rate(NULL, devname, parent, 0,
442 					      pdata->fixed_clk_rate);
443 		goto out;
444 	}
445 
446 	if (dev_desc->flags & LPSS_CLK_GATE) {
447 		clk = clk_register_gate(NULL, devname, parent, 0,
448 					prv_base, 0, 0, NULL);
449 		parent = devname;
450 	}
451 
452 	if (dev_desc->flags & LPSS_CLK_DIVIDER) {
453 		/* Prevent division by zero */
454 		if (!readl(prv_base))
455 			writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
456 
457 		clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
458 		if (!clk_name)
459 			return -ENOMEM;
460 		clk = clk_register_fractional_divider(NULL, clk_name, parent,
461 						      CLK_FRAC_DIVIDER_POWER_OF_TWO_PS,
462 						      prv_base, 1, 15, 16, 15, 0, NULL);
463 		parent = clk_name;
464 
465 		clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
466 		if (!clk_name) {
467 			kfree(parent);
468 			return -ENOMEM;
469 		}
470 		clk = clk_register_gate(NULL, clk_name, parent,
471 					CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
472 					prv_base, 31, 0, NULL);
473 		kfree(parent);
474 		kfree(clk_name);
475 	}
476 out:
477 	if (IS_ERR(clk))
478 		return PTR_ERR(clk);
479 
480 	pdata->clk = clk;
481 	clk_register_clkdev(clk, dev_desc->clk_con_id, devname);
482 	return 0;
483 }
484 
485 struct lpss_device_links {
486 	const char *supplier_hid;
487 	const char *supplier_uid;
488 	const char *consumer_hid;
489 	const char *consumer_uid;
490 	u32 flags;
491 	const struct dmi_system_id *dep_missing_ids;
492 };
493 
494 /* Please keep this list sorted alphabetically by vendor and model */
495 static const struct dmi_system_id i2c1_dep_missing_dmi_ids[] = {
496 	{
497 		.matches = {
498 			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
499 			DMI_MATCH(DMI_PRODUCT_NAME, "T200TA"),
500 		},
501 	},
502 	{}
503 };
504 
505 /*
506  * The _DEP method is used to identify dependencies but instead of creating
507  * device links for every handle in _DEP, only links in the following list are
508  * created. That is necessary because, in the general case, _DEP can refer to
509  * devices that might not have drivers, or that are on different buses, or where
510  * the supplier is not enumerated until after the consumer is probed.
511  */
512 static const struct lpss_device_links lpss_device_links[] = {
513 	/* CHT External sdcard slot controller depends on PMIC I2C ctrl */
514 	{"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME},
515 	/* CHT iGPU depends on PMIC I2C controller */
516 	{"808622C1", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
517 	/* BYT iGPU depends on the Embedded Controller I2C controller (UID 1) */
518 	{"80860F41", "1", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME,
519 	 i2c1_dep_missing_dmi_ids},
520 	/* BYT CR iGPU depends on PMIC I2C controller (UID 5 on CR) */
521 	{"80860F41", "5", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
522 	/* BYT iGPU depends on PMIC I2C controller (UID 7 on non CR) */
523 	{"80860F41", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
524 };
525 
526 static bool acpi_lpss_is_supplier(struct acpi_device *adev,
527 				  const struct lpss_device_links *link)
528 {
529 	return acpi_dev_hid_uid_match(adev, link->supplier_hid, link->supplier_uid);
530 }
531 
532 static bool acpi_lpss_is_consumer(struct acpi_device *adev,
533 				  const struct lpss_device_links *link)
534 {
535 	return acpi_dev_hid_uid_match(adev, link->consumer_hid, link->consumer_uid);
536 }
537 
538 struct hid_uid {
539 	const char *hid;
540 	const char *uid;
541 };
542 
543 static int match_hid_uid(struct device *dev, const void *data)
544 {
545 	struct acpi_device *adev = ACPI_COMPANION(dev);
546 	const struct hid_uid *id = data;
547 
548 	if (!adev)
549 		return 0;
550 
551 	return acpi_dev_hid_uid_match(adev, id->hid, id->uid);
552 }
553 
554 static struct device *acpi_lpss_find_device(const char *hid, const char *uid)
555 {
556 	struct device *dev;
557 
558 	struct hid_uid data = {
559 		.hid = hid,
560 		.uid = uid,
561 	};
562 
563 	dev = bus_find_device(&platform_bus_type, NULL, &data, match_hid_uid);
564 	if (dev)
565 		return dev;
566 
567 	return bus_find_device(&pci_bus_type, NULL, &data, match_hid_uid);
568 }
569 
570 static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle)
571 {
572 	struct acpi_handle_list dep_devices;
573 	acpi_status status;
574 	int i;
575 
576 	if (!acpi_has_method(adev->handle, "_DEP"))
577 		return false;
578 
579 	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
580 					 &dep_devices);
581 	if (ACPI_FAILURE(status)) {
582 		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
583 		return false;
584 	}
585 
586 	for (i = 0; i < dep_devices.count; i++) {
587 		if (dep_devices.handles[i] == handle)
588 			return true;
589 	}
590 
591 	return false;
592 }
593 
594 static void acpi_lpss_link_consumer(struct device *dev1,
595 				    const struct lpss_device_links *link)
596 {
597 	struct device *dev2;
598 
599 	dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid);
600 	if (!dev2)
601 		return;
602 
603 	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
604 	    || acpi_lpss_dep(ACPI_COMPANION(dev2), ACPI_HANDLE(dev1)))
605 		device_link_add(dev2, dev1, link->flags);
606 
607 	put_device(dev2);
608 }
609 
610 static void acpi_lpss_link_supplier(struct device *dev1,
611 				    const struct lpss_device_links *link)
612 {
613 	struct device *dev2;
614 
615 	dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid);
616 	if (!dev2)
617 		return;
618 
619 	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
620 	    || acpi_lpss_dep(ACPI_COMPANION(dev1), ACPI_HANDLE(dev2)))
621 		device_link_add(dev1, dev2, link->flags);
622 
623 	put_device(dev2);
624 }
625 
626 static void acpi_lpss_create_device_links(struct acpi_device *adev,
627 					  struct platform_device *pdev)
628 {
629 	int i;
630 
631 	for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) {
632 		const struct lpss_device_links *link = &lpss_device_links[i];
633 
634 		if (acpi_lpss_is_supplier(adev, link))
635 			acpi_lpss_link_consumer(&pdev->dev, link);
636 
637 		if (acpi_lpss_is_consumer(adev, link))
638 			acpi_lpss_link_supplier(&pdev->dev, link);
639 	}
640 }
641 
642 static int acpi_lpss_create_device(struct acpi_device *adev,
643 				   const struct acpi_device_id *id)
644 {
645 	const struct lpss_device_desc *dev_desc;
646 	struct lpss_private_data *pdata;
647 	struct resource_entry *rentry;
648 	struct list_head resource_list;
649 	struct platform_device *pdev;
650 	int ret;
651 
652 	dev_desc = (const struct lpss_device_desc *)id->driver_data;
653 	if (!dev_desc) {
654 		pdev = acpi_create_platform_device(adev, NULL);
655 		return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
656 	}
657 	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
658 	if (!pdata)
659 		return -ENOMEM;
660 
661 	INIT_LIST_HEAD(&resource_list);
662 	ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL);
663 	if (ret < 0)
664 		goto err_out;
665 
666 	list_for_each_entry(rentry, &resource_list, node)
667 		if (resource_type(rentry->res) == IORESOURCE_MEM) {
668 			if (dev_desc->prv_size_override)
669 				pdata->mmio_size = dev_desc->prv_size_override;
670 			else
671 				pdata->mmio_size = resource_size(rentry->res);
672 			pdata->mmio_base = ioremap(rentry->res->start,
673 						   pdata->mmio_size);
674 			break;
675 		}
676 
677 	acpi_dev_free_resource_list(&resource_list);
678 
679 	if (!pdata->mmio_base) {
680 		/* Avoid acpi_bus_attach() instantiating a pdev for this dev. */
681 		adev->pnp.type.platform_id = 0;
682 		/* Skip the device, but continue the namespace scan. */
683 		ret = 0;
684 		goto err_out;
685 	}
686 
687 	pdata->adev = adev;
688 	pdata->dev_desc = dev_desc;
689 
690 	if (dev_desc->setup)
691 		dev_desc->setup(pdata);
692 
693 	if (dev_desc->flags & LPSS_CLK) {
694 		ret = register_device_clock(adev, pdata);
695 		if (ret) {
696 			/* Skip the device, but continue the namespace scan. */
697 			ret = 0;
698 			goto err_out;
699 		}
700 	}
701 
702 	/*
703 	 * This works around a known issue in ACPI tables where LPSS devices
704 	 * have _PS0 and _PS3 without _PSC (and no power resources), so
705 	 * acpi_bus_init_power() will assume that the BIOS has put them into D0.
706 	 */
707 	acpi_device_fix_up_power(adev);
708 
709 	adev->driver_data = pdata;
710 	pdev = acpi_create_platform_device(adev, dev_desc->properties);
711 	if (!IS_ERR_OR_NULL(pdev)) {
712 		acpi_lpss_create_device_links(adev, pdev);
713 		return 1;
714 	}
715 
716 	ret = PTR_ERR(pdev);
717 	adev->driver_data = NULL;
718 
719  err_out:
720 	kfree(pdata);
721 	return ret;
722 }
723 
724 static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
725 {
726 	return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
727 }
728 
729 static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
730 			     unsigned int reg)
731 {
732 	writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
733 }
734 
735 static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
736 {
737 	struct acpi_device *adev = ACPI_COMPANION(dev);
738 	struct lpss_private_data *pdata;
739 	unsigned long flags;
740 	int ret;
741 
742 	if (WARN_ON(!adev))
743 		return -ENODEV;
744 
745 	spin_lock_irqsave(&dev->power.lock, flags);
746 	if (pm_runtime_suspended(dev)) {
747 		ret = -EAGAIN;
748 		goto out;
749 	}
750 	pdata = acpi_driver_data(adev);
751 	if (WARN_ON(!pdata || !pdata->mmio_base)) {
752 		ret = -ENODEV;
753 		goto out;
754 	}
755 	*val = __lpss_reg_read(pdata, reg);
756 	ret = 0;
757 
758  out:
759 	spin_unlock_irqrestore(&dev->power.lock, flags);
760 	return ret;
761 }
762 
763 static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
764 			     char *buf)
765 {
766 	u32 ltr_value = 0;
767 	unsigned int reg;
768 	int ret;
769 
770 	reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
771 	ret = lpss_reg_read(dev, reg, &ltr_value);
772 	if (ret)
773 		return ret;
774 
775 	return sysfs_emit(buf, "%08x\n", ltr_value);
776 }
777 
778 static ssize_t lpss_ltr_mode_show(struct device *dev,
779 				  struct device_attribute *attr, char *buf)
780 {
781 	u32 ltr_mode = 0;
782 	char *outstr;
783 	int ret;
784 
785 	ret = lpss_reg_read(dev, LPSS_GENERAL, &ltr_mode);
786 	if (ret)
787 		return ret;
788 
789 	outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
790 	return sprintf(buf, "%s\n", outstr);
791 }
792 
793 static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
794 static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
795 static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
796 
797 static struct attribute *lpss_attrs[] = {
798 	&dev_attr_auto_ltr.attr,
799 	&dev_attr_sw_ltr.attr,
800 	&dev_attr_ltr_mode.attr,
801 	NULL,
802 };
803 
804 static const struct attribute_group lpss_attr_group = {
805 	.attrs = lpss_attrs,
806 	.name = "lpss_ltr",
807 };
808 
809 static void acpi_lpss_set_ltr(struct device *dev, s32 val)
810 {
811 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
812 	u32 ltr_mode, ltr_val;
813 
814 	ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
815 	if (val < 0) {
816 		if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
817 			ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
818 			__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
819 		}
820 		return;
821 	}
822 	ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
823 	if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
824 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
825 		val = LPSS_LTR_MAX_VAL;
826 	} else if (val > LPSS_LTR_MAX_VAL) {
827 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
828 		val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
829 	} else {
830 		ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
831 	}
832 	ltr_val |= val;
833 	__lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
834 	if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
835 		ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
836 		__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
837 	}
838 }
839 
840 #ifdef CONFIG_PM
841 /**
842  * acpi_lpss_save_ctx() - Save the private registers of LPSS device
843  * @dev: LPSS device
844  * @pdata: pointer to the private data of the LPSS device
845  *
846  * Most LPSS devices have private registers which may loose their context when
847  * the device is powered down. acpi_lpss_save_ctx() saves those registers into
848  * prv_reg_ctx array.
849  */
850 static void acpi_lpss_save_ctx(struct device *dev,
851 			       struct lpss_private_data *pdata)
852 {
853 	unsigned int i;
854 
855 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
856 		unsigned long offset = i * sizeof(u32);
857 
858 		pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
859 		dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
860 			pdata->prv_reg_ctx[i], offset);
861 	}
862 }
863 
864 /**
865  * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
866  * @dev: LPSS device
867  * @pdata: pointer to the private data of the LPSS device
868  *
869  * Restores the registers that were previously stored with acpi_lpss_save_ctx().
870  */
871 static void acpi_lpss_restore_ctx(struct device *dev,
872 				  struct lpss_private_data *pdata)
873 {
874 	unsigned int i;
875 
876 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
877 		unsigned long offset = i * sizeof(u32);
878 
879 		__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
880 		dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
881 			pdata->prv_reg_ctx[i], offset);
882 	}
883 }
884 
885 static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
886 {
887 	/*
888 	 * The following delay is needed or the subsequent write operations may
889 	 * fail. The LPSS devices are actually PCI devices and the PCI spec
890 	 * expects 10ms delay before the device can be accessed after D3 to D0
891 	 * transition. However some platforms like BSW does not need this delay.
892 	 */
893 	unsigned int delay = 10;	/* default 10ms delay */
894 
895 	if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)
896 		delay = 0;
897 
898 	msleep(delay);
899 }
900 
901 static int acpi_lpss_activate(struct device *dev)
902 {
903 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
904 	int ret;
905 
906 	ret = acpi_dev_resume(dev);
907 	if (ret)
908 		return ret;
909 
910 	acpi_lpss_d3_to_d0_delay(pdata);
911 
912 	/*
913 	 * This is called only on ->probe() stage where a device is either in
914 	 * known state defined by BIOS or most likely powered off. Due to this
915 	 * we have to deassert reset line to be sure that ->probe() will
916 	 * recognize the device.
917 	 */
918 	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
919 		lpss_deassert_reset(pdata);
920 
921 #ifdef CONFIG_PM
922 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX_ONCE)
923 		acpi_lpss_save_ctx(dev, pdata);
924 #endif
925 
926 	return 0;
927 }
928 
929 static void acpi_lpss_dismiss(struct device *dev)
930 {
931 	acpi_dev_suspend(dev, false);
932 }
933 
934 /* IOSF SB for LPSS island */
935 #define LPSS_IOSF_UNIT_LPIOEP		0xA0
936 #define LPSS_IOSF_UNIT_LPIO1		0xAB
937 #define LPSS_IOSF_UNIT_LPIO2		0xAC
938 
939 #define LPSS_IOSF_PMCSR			0x84
940 #define LPSS_PMCSR_D0			0
941 #define LPSS_PMCSR_D3hot		3
942 #define LPSS_PMCSR_Dx_MASK		GENMASK(1, 0)
943 
944 #define LPSS_IOSF_GPIODEF0		0x154
945 #define LPSS_GPIODEF0_DMA1_D3		BIT(2)
946 #define LPSS_GPIODEF0_DMA2_D3		BIT(3)
947 #define LPSS_GPIODEF0_DMA_D3_MASK	GENMASK(3, 2)
948 #define LPSS_GPIODEF0_DMA_LLP		BIT(13)
949 
950 static DEFINE_MUTEX(lpss_iosf_mutex);
951 static bool lpss_iosf_d3_entered = true;
952 
953 static void lpss_iosf_enter_d3_state(void)
954 {
955 	u32 value1 = 0;
956 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
957 	u32 value2 = LPSS_PMCSR_D3hot;
958 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
959 	/*
960 	 * PMC provides an information about actual status of the LPSS devices.
961 	 * Here we read the values related to LPSS power island, i.e. LPSS
962 	 * devices, excluding both LPSS DMA controllers, along with SCC domain.
963 	 */
964 	u32 func_dis, d3_sts_0, pmc_status;
965 	int ret;
966 
967 	ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);
968 	if (ret)
969 		return;
970 
971 	mutex_lock(&lpss_iosf_mutex);
972 
973 	ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);
974 	if (ret)
975 		goto exit;
976 
977 	/*
978 	 * Get the status of entire LPSS power island per device basis.
979 	 * Shutdown both LPSS DMA controllers if and only if all other devices
980 	 * are already in D3hot.
981 	 */
982 	pmc_status = (~(d3_sts_0 | func_dis)) & pmc_atom_d3_mask;
983 	if (pmc_status)
984 		goto exit;
985 
986 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
987 			LPSS_IOSF_PMCSR, value2, mask2);
988 
989 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
990 			LPSS_IOSF_PMCSR, value2, mask2);
991 
992 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
993 			LPSS_IOSF_GPIODEF0, value1, mask1);
994 
995 	lpss_iosf_d3_entered = true;
996 
997 exit:
998 	mutex_unlock(&lpss_iosf_mutex);
999 }
1000 
1001 static void lpss_iosf_exit_d3_state(void)
1002 {
1003 	u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 |
1004 		     LPSS_GPIODEF0_DMA_LLP;
1005 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
1006 	u32 value2 = LPSS_PMCSR_D0;
1007 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
1008 
1009 	mutex_lock(&lpss_iosf_mutex);
1010 
1011 	if (!lpss_iosf_d3_entered)
1012 		goto exit;
1013 
1014 	lpss_iosf_d3_entered = false;
1015 
1016 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
1017 			LPSS_IOSF_GPIODEF0, value1, mask1);
1018 
1019 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
1020 			LPSS_IOSF_PMCSR, value2, mask2);
1021 
1022 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
1023 			LPSS_IOSF_PMCSR, value2, mask2);
1024 
1025 exit:
1026 	mutex_unlock(&lpss_iosf_mutex);
1027 }
1028 
1029 static int acpi_lpss_suspend(struct device *dev, bool wakeup)
1030 {
1031 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1032 	int ret;
1033 
1034 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
1035 		acpi_lpss_save_ctx(dev, pdata);
1036 
1037 	ret = acpi_dev_suspend(dev, wakeup);
1038 
1039 	/*
1040 	 * This call must be last in the sequence, otherwise PMC will return
1041 	 * wrong status for devices being about to be powered off. See
1042 	 * lpss_iosf_enter_d3_state() for further information.
1043 	 */
1044 	if (acpi_target_system_state() == ACPI_STATE_S0 &&
1045 	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1046 		lpss_iosf_enter_d3_state();
1047 
1048 	return ret;
1049 }
1050 
1051 static int acpi_lpss_resume(struct device *dev)
1052 {
1053 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1054 	int ret;
1055 
1056 	/*
1057 	 * This call is kept first to be in symmetry with
1058 	 * acpi_lpss_runtime_suspend() one.
1059 	 */
1060 	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1061 		lpss_iosf_exit_d3_state();
1062 
1063 	ret = acpi_dev_resume(dev);
1064 	if (ret)
1065 		return ret;
1066 
1067 	acpi_lpss_d3_to_d0_delay(pdata);
1068 
1069 	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
1070 		acpi_lpss_restore_ctx(dev, pdata);
1071 
1072 	return 0;
1073 }
1074 
1075 #ifdef CONFIG_PM_SLEEP
1076 static int acpi_lpss_do_suspend_late(struct device *dev)
1077 {
1078 	int ret;
1079 
1080 	if (dev_pm_skip_suspend(dev))
1081 		return 0;
1082 
1083 	ret = pm_generic_suspend_late(dev);
1084 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1085 }
1086 
1087 static int acpi_lpss_suspend_late(struct device *dev)
1088 {
1089 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1090 
1091 	if (pdata->dev_desc->resume_from_noirq)
1092 		return 0;
1093 
1094 	return acpi_lpss_do_suspend_late(dev);
1095 }
1096 
1097 static int acpi_lpss_suspend_noirq(struct device *dev)
1098 {
1099 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1100 	int ret;
1101 
1102 	if (pdata->dev_desc->resume_from_noirq) {
1103 		/*
1104 		 * The driver's ->suspend_late callback will be invoked by
1105 		 * acpi_lpss_do_suspend_late(), with the assumption that the
1106 		 * driver really wanted to run that code in ->suspend_noirq, but
1107 		 * it could not run after acpi_dev_suspend() and the driver
1108 		 * expected the latter to be called in the "late" phase.
1109 		 */
1110 		ret = acpi_lpss_do_suspend_late(dev);
1111 		if (ret)
1112 			return ret;
1113 	}
1114 
1115 	return acpi_subsys_suspend_noirq(dev);
1116 }
1117 
1118 static int acpi_lpss_do_resume_early(struct device *dev)
1119 {
1120 	int ret = acpi_lpss_resume(dev);
1121 
1122 	return ret ? ret : pm_generic_resume_early(dev);
1123 }
1124 
1125 static int acpi_lpss_resume_early(struct device *dev)
1126 {
1127 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1128 
1129 	if (pdata->dev_desc->resume_from_noirq)
1130 		return 0;
1131 
1132 	if (dev_pm_skip_resume(dev))
1133 		return 0;
1134 
1135 	return acpi_lpss_do_resume_early(dev);
1136 }
1137 
1138 static int acpi_lpss_resume_noirq(struct device *dev)
1139 {
1140 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1141 	int ret;
1142 
1143 	/* Follow acpi_subsys_resume_noirq(). */
1144 	if (dev_pm_skip_resume(dev))
1145 		return 0;
1146 
1147 	ret = pm_generic_resume_noirq(dev);
1148 	if (ret)
1149 		return ret;
1150 
1151 	if (!pdata->dev_desc->resume_from_noirq)
1152 		return 0;
1153 
1154 	/*
1155 	 * The driver's ->resume_early callback will be invoked by
1156 	 * acpi_lpss_do_resume_early(), with the assumption that the driver
1157 	 * really wanted to run that code in ->resume_noirq, but it could not
1158 	 * run before acpi_dev_resume() and the driver expected the latter to be
1159 	 * called in the "early" phase.
1160 	 */
1161 	return acpi_lpss_do_resume_early(dev);
1162 }
1163 
1164 static int acpi_lpss_do_restore_early(struct device *dev)
1165 {
1166 	int ret = acpi_lpss_resume(dev);
1167 
1168 	return ret ? ret : pm_generic_restore_early(dev);
1169 }
1170 
1171 static int acpi_lpss_restore_early(struct device *dev)
1172 {
1173 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1174 
1175 	if (pdata->dev_desc->resume_from_noirq)
1176 		return 0;
1177 
1178 	return acpi_lpss_do_restore_early(dev);
1179 }
1180 
1181 static int acpi_lpss_restore_noirq(struct device *dev)
1182 {
1183 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1184 	int ret;
1185 
1186 	ret = pm_generic_restore_noirq(dev);
1187 	if (ret)
1188 		return ret;
1189 
1190 	if (!pdata->dev_desc->resume_from_noirq)
1191 		return 0;
1192 
1193 	/* This is analogous to what happens in acpi_lpss_resume_noirq(). */
1194 	return acpi_lpss_do_restore_early(dev);
1195 }
1196 
1197 static int acpi_lpss_do_poweroff_late(struct device *dev)
1198 {
1199 	int ret = pm_generic_poweroff_late(dev);
1200 
1201 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1202 }
1203 
1204 static int acpi_lpss_poweroff_late(struct device *dev)
1205 {
1206 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1207 
1208 	if (dev_pm_skip_suspend(dev))
1209 		return 0;
1210 
1211 	if (pdata->dev_desc->resume_from_noirq)
1212 		return 0;
1213 
1214 	return acpi_lpss_do_poweroff_late(dev);
1215 }
1216 
1217 static int acpi_lpss_poweroff_noirq(struct device *dev)
1218 {
1219 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1220 
1221 	if (dev_pm_skip_suspend(dev))
1222 		return 0;
1223 
1224 	if (pdata->dev_desc->resume_from_noirq) {
1225 		/* This is analogous to the acpi_lpss_suspend_noirq() case. */
1226 		int ret = acpi_lpss_do_poweroff_late(dev);
1227 
1228 		if (ret)
1229 			return ret;
1230 	}
1231 
1232 	return pm_generic_poweroff_noirq(dev);
1233 }
1234 #endif /* CONFIG_PM_SLEEP */
1235 
1236 static int acpi_lpss_runtime_suspend(struct device *dev)
1237 {
1238 	int ret = pm_generic_runtime_suspend(dev);
1239 
1240 	return ret ? ret : acpi_lpss_suspend(dev, true);
1241 }
1242 
1243 static int acpi_lpss_runtime_resume(struct device *dev)
1244 {
1245 	int ret = acpi_lpss_resume(dev);
1246 
1247 	return ret ? ret : pm_generic_runtime_resume(dev);
1248 }
1249 #endif /* CONFIG_PM */
1250 
1251 static struct dev_pm_domain acpi_lpss_pm_domain = {
1252 #ifdef CONFIG_PM
1253 	.activate = acpi_lpss_activate,
1254 	.dismiss = acpi_lpss_dismiss,
1255 #endif
1256 	.ops = {
1257 #ifdef CONFIG_PM
1258 #ifdef CONFIG_PM_SLEEP
1259 		.prepare = acpi_subsys_prepare,
1260 		.complete = acpi_subsys_complete,
1261 		.suspend = acpi_subsys_suspend,
1262 		.suspend_late = acpi_lpss_suspend_late,
1263 		.suspend_noirq = acpi_lpss_suspend_noirq,
1264 		.resume_noirq = acpi_lpss_resume_noirq,
1265 		.resume_early = acpi_lpss_resume_early,
1266 		.freeze = acpi_subsys_freeze,
1267 		.poweroff = acpi_subsys_poweroff,
1268 		.poweroff_late = acpi_lpss_poweroff_late,
1269 		.poweroff_noirq = acpi_lpss_poweroff_noirq,
1270 		.restore_noirq = acpi_lpss_restore_noirq,
1271 		.restore_early = acpi_lpss_restore_early,
1272 #endif
1273 		.runtime_suspend = acpi_lpss_runtime_suspend,
1274 		.runtime_resume = acpi_lpss_runtime_resume,
1275 #endif
1276 	},
1277 };
1278 
1279 static int acpi_lpss_platform_notify(struct notifier_block *nb,
1280 				     unsigned long action, void *data)
1281 {
1282 	struct platform_device *pdev = to_platform_device(data);
1283 	struct lpss_private_data *pdata;
1284 	struct acpi_device *adev;
1285 	const struct acpi_device_id *id;
1286 
1287 	id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
1288 	if (!id || !id->driver_data)
1289 		return 0;
1290 
1291 	adev = ACPI_COMPANION(&pdev->dev);
1292 	if (!adev)
1293 		return 0;
1294 
1295 	pdata = acpi_driver_data(adev);
1296 	if (!pdata)
1297 		return 0;
1298 
1299 	if (pdata->mmio_base &&
1300 	    pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
1301 		dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
1302 		return 0;
1303 	}
1304 
1305 	switch (action) {
1306 	case BUS_NOTIFY_BIND_DRIVER:
1307 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1308 		break;
1309 	case BUS_NOTIFY_DRIVER_NOT_BOUND:
1310 	case BUS_NOTIFY_UNBOUND_DRIVER:
1311 		dev_pm_domain_set(&pdev->dev, NULL);
1312 		break;
1313 	case BUS_NOTIFY_ADD_DEVICE:
1314 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1315 		if (pdata->dev_desc->flags & LPSS_LTR)
1316 			return sysfs_create_group(&pdev->dev.kobj,
1317 						  &lpss_attr_group);
1318 		break;
1319 	case BUS_NOTIFY_DEL_DEVICE:
1320 		if (pdata->dev_desc->flags & LPSS_LTR)
1321 			sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
1322 		dev_pm_domain_set(&pdev->dev, NULL);
1323 		break;
1324 	default:
1325 		break;
1326 	}
1327 
1328 	return 0;
1329 }
1330 
1331 static struct notifier_block acpi_lpss_nb = {
1332 	.notifier_call = acpi_lpss_platform_notify,
1333 };
1334 
1335 static void acpi_lpss_bind(struct device *dev)
1336 {
1337 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1338 
1339 	if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
1340 		return;
1341 
1342 	if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
1343 		dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
1344 	else
1345 		dev_err(dev, "MMIO size insufficient to access LTR\n");
1346 }
1347 
1348 static void acpi_lpss_unbind(struct device *dev)
1349 {
1350 	dev->power.set_latency_tolerance = NULL;
1351 }
1352 
1353 static struct acpi_scan_handler lpss_handler = {
1354 	.ids = acpi_lpss_device_ids,
1355 	.attach = acpi_lpss_create_device,
1356 	.bind = acpi_lpss_bind,
1357 	.unbind = acpi_lpss_unbind,
1358 };
1359 
1360 void __init acpi_lpss_init(void)
1361 {
1362 	const struct x86_cpu_id *id;
1363 	int ret;
1364 
1365 	ret = lpss_atom_clk_init();
1366 	if (ret)
1367 		return;
1368 
1369 	id = x86_match_cpu(lpss_cpu_ids);
1370 	if (id)
1371 		lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;
1372 
1373 	bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
1374 	acpi_scan_add_handler(&lpss_handler);
1375 }
1376 
1377 #else
1378 
1379 static struct acpi_scan_handler lpss_handler = {
1380 	.ids = acpi_lpss_device_ids,
1381 };
1382 
1383 void __init acpi_lpss_init(void)
1384 {
1385 	acpi_scan_add_handler(&lpss_handler);
1386 }
1387 
1388 #endif /* CONFIG_X86_INTEL_LPSS */
1389