xref: /linux/drivers/acpi/x86/lpss.c (revision dde8ec86c3fdb2666f55a6c33df097cf5384b057)
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 	/* Only call pwm_add_table for the first PWM controller */
171 	if (acpi_dev_uid_match(pdata->adev, 1))
172 		pwm_add_table(byt_pwm_lookup, ARRAY_SIZE(byt_pwm_lookup));
173 }
174 
175 #define LPSS_I2C_ENABLE			0x6c
176 
177 static void byt_i2c_setup(struct lpss_private_data *pdata)
178 {
179 	acpi_handle handle = pdata->adev->handle;
180 	unsigned long long shared_host = 0;
181 	acpi_status status;
182 	u64 uid;
183 
184 	/* Expected to always be successfull, but better safe then sorry */
185 	if (!acpi_dev_uid_to_integer(pdata->adev, &uid) && uid) {
186 		/* Detect I2C bus shared with PUNIT and ignore its d3 status */
187 		status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host);
188 		if (ACPI_SUCCESS(status) && shared_host)
189 			pmc_atom_d3_mask &= ~(BIT_LPSS2_F1_I2C1 << (uid - 1));
190 	}
191 
192 	lpss_deassert_reset(pdata);
193 
194 	if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset))
195 		pdata->fixed_clk_rate = 133000000;
196 
197 	writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
198 }
199 
200 /*
201  * BSW PWM1 is used for backlight control by the i915 driver
202  * BSW PWM2 is used for backlight control for fixed (etched into the glass)
203  * touch controls on some models. These touch-controls have specialized
204  * drivers which know they need the "pwm_soc_lpss_2" con-id.
205  */
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 	PWM_LOOKUP_WITH_MODULE("80862289:00", 0, NULL,
211 			       "pwm_soc_lpss_2", 0, PWM_POLARITY_NORMAL,
212 			       "pwm-lpss-platform"),
213 };
214 
215 static void bsw_pwm_setup(struct lpss_private_data *pdata)
216 {
217 	/* Only call pwm_add_table for the first PWM controller */
218 	if (acpi_dev_uid_match(pdata->adev, 1))
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 bsw_pwm2_dev_desc = {
275 	.flags = LPSS_SAVE_CTX_ONCE | LPSS_NO_D3_DELAY,
276 	.prv_offset = 0x800,
277 	.resume_from_noirq = true,
278 };
279 
280 static const struct lpss_device_desc byt_uart_dev_desc = {
281 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
282 	.clk_con_id = "baudclk",
283 	.prv_offset = 0x800,
284 	.setup = lpss_uart_setup,
285 	.properties = uart_properties,
286 };
287 
288 static const struct lpss_device_desc bsw_uart_dev_desc = {
289 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
290 			| LPSS_NO_D3_DELAY,
291 	.clk_con_id = "baudclk",
292 	.prv_offset = 0x800,
293 	.setup = lpss_uart_setup,
294 	.properties = uart_properties,
295 };
296 
297 static const struct property_entry byt_spi_properties[] = {
298 	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_BYT_SSP),
299 	{ }
300 };
301 
302 static const struct lpss_device_desc byt_spi_dev_desc = {
303 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
304 	.prv_offset = 0x400,
305 	.properties = byt_spi_properties,
306 };
307 
308 static const struct lpss_device_desc byt_sdio_dev_desc = {
309 	.flags = LPSS_CLK,
310 };
311 
312 static const struct lpss_device_desc byt_i2c_dev_desc = {
313 	.flags = LPSS_CLK | LPSS_SAVE_CTX,
314 	.prv_offset = 0x800,
315 	.setup = byt_i2c_setup,
316 	.resume_from_noirq = true,
317 };
318 
319 static const struct lpss_device_desc bsw_i2c_dev_desc = {
320 	.flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
321 	.prv_offset = 0x800,
322 	.setup = byt_i2c_setup,
323 	.resume_from_noirq = true,
324 };
325 
326 static const struct property_entry bsw_spi_properties[] = {
327 	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_BSW_SSP),
328 	PROPERTY_ENTRY_U32("num-cs", 2),
329 	{ }
330 };
331 
332 static const struct lpss_device_desc bsw_spi_dev_desc = {
333 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
334 			| LPSS_NO_D3_DELAY,
335 	.prv_offset = 0x400,
336 	.setup = lpss_deassert_reset,
337 	.properties = bsw_spi_properties,
338 };
339 
340 static const struct x86_cpu_id lpss_cpu_ids[] = {
341 	X86_MATCH_VFM(INTEL_ATOM_SILVERMONT,	NULL),
342 	X86_MATCH_VFM(INTEL_ATOM_AIRMONT,	NULL),
343 	{}
344 };
345 
346 #else
347 
348 #define LPSS_ADDR(desc) (0UL)
349 
350 #endif /* CONFIG_X86_INTEL_LPSS */
351 
352 static const struct acpi_device_id acpi_lpss_device_ids[] = {
353 	/* Generic LPSS devices */
354 	{ "INTL9C60", LPSS_ADDR(lpss_dma_desc) },
355 
356 	/* Lynxpoint LPSS devices */
357 	{ "INT33C0", LPSS_ADDR(lpt_spi_dev_desc) },
358 	{ "INT33C1", LPSS_ADDR(lpt_spi_dev_desc) },
359 	{ "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },
360 	{ "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },
361 	{ "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },
362 	{ "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },
363 	{ "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },
364 
365 	/* BayTrail LPSS devices */
366 	{ "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },
367 	{ "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },
368 	{ "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },
369 	{ "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },
370 	{ "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },
371 
372 	/* Braswell LPSS devices */
373 	{ "80862286", LPSS_ADDR(lpss_dma_desc) },
374 	{ "80862288", LPSS_ADDR(bsw_pwm_dev_desc) },
375 	{ "80862289", LPSS_ADDR(bsw_pwm2_dev_desc) },
376 	{ "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },
377 	{ "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },
378 	{ "808622C0", LPSS_ADDR(lpss_dma_desc) },
379 	{ "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) },
380 
381 	/* Broadwell LPSS devices */
382 	{ "INT3430", LPSS_ADDR(lpt_spi_dev_desc) },
383 	{ "INT3431", LPSS_ADDR(lpt_spi_dev_desc) },
384 	{ "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },
385 	{ "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },
386 	{ "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },
387 	{ "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },
388 	{ "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },
389 
390 	/* Wildcat Point LPSS devices */
391 	{ "INT3438", LPSS_ADDR(lpt_spi_dev_desc) },
392 
393 	{ }
394 };
395 
396 #ifdef CONFIG_X86_INTEL_LPSS
397 
398 /* LPSS main clock device. */
399 static struct platform_device *lpss_clk_dev;
400 
401 static inline void lpt_register_clock_device(void)
402 {
403 	lpss_clk_dev = platform_device_register_simple("clk-lpss-atom",
404 						       PLATFORM_DEVID_NONE,
405 						       NULL, 0);
406 }
407 
408 static int register_device_clock(struct acpi_device *adev,
409 				 struct lpss_private_data *pdata)
410 {
411 	const struct lpss_device_desc *dev_desc = pdata->dev_desc;
412 	const char *devname = dev_name(&adev->dev);
413 	struct clk *clk;
414 	struct lpss_clk_data *clk_data;
415 	const char *parent, *clk_name;
416 	void __iomem *prv_base;
417 
418 	if (!lpss_clk_dev)
419 		lpt_register_clock_device();
420 
421 	if (IS_ERR(lpss_clk_dev))
422 		return PTR_ERR(lpss_clk_dev);
423 
424 	clk_data = platform_get_drvdata(lpss_clk_dev);
425 	if (!clk_data)
426 		return -ENODEV;
427 	clk = clk_data->clk;
428 
429 	if (!pdata->mmio_base
430 	    || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
431 		return -ENODATA;
432 
433 	parent = clk_data->name;
434 	prv_base = pdata->mmio_base + dev_desc->prv_offset;
435 
436 	if (pdata->fixed_clk_rate) {
437 		clk = clk_register_fixed_rate(NULL, devname, parent, 0,
438 					      pdata->fixed_clk_rate);
439 		goto out;
440 	}
441 
442 	if (dev_desc->flags & LPSS_CLK_GATE) {
443 		clk = clk_register_gate(NULL, devname, parent, 0,
444 					prv_base, 0, 0, NULL);
445 		parent = devname;
446 	}
447 
448 	if (dev_desc->flags & LPSS_CLK_DIVIDER) {
449 		/* Prevent division by zero */
450 		if (!readl(prv_base))
451 			writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
452 
453 		clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
454 		if (!clk_name)
455 			return -ENOMEM;
456 		clk = clk_register_fractional_divider(NULL, clk_name, parent,
457 						      0, prv_base, 1, 15, 16, 15,
458 						      CLK_FRAC_DIVIDER_POWER_OF_TWO_PS,
459 						      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 void acpi_lpss_link_consumer(struct device *dev1,
568 				    const struct lpss_device_links *link)
569 {
570 	struct device *dev2;
571 
572 	dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid);
573 	if (!dev2)
574 		return;
575 
576 	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
577 	    || acpi_device_dep(ACPI_HANDLE(dev2), ACPI_HANDLE(dev1)))
578 		device_link_add(dev2, dev1, link->flags);
579 
580 	put_device(dev2);
581 }
582 
583 static void acpi_lpss_link_supplier(struct device *dev1,
584 				    const struct lpss_device_links *link)
585 {
586 	struct device *dev2;
587 
588 	dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid);
589 	if (!dev2)
590 		return;
591 
592 	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
593 	    || acpi_device_dep(ACPI_HANDLE(dev1), ACPI_HANDLE(dev2)))
594 		device_link_add(dev1, dev2, link->flags);
595 
596 	put_device(dev2);
597 }
598 
599 static void acpi_lpss_create_device_links(struct acpi_device *adev,
600 					  struct platform_device *pdev)
601 {
602 	int i;
603 
604 	for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) {
605 		const struct lpss_device_links *link = &lpss_device_links[i];
606 
607 		if (acpi_lpss_is_supplier(adev, link))
608 			acpi_lpss_link_consumer(&pdev->dev, link);
609 
610 		if (acpi_lpss_is_consumer(adev, link))
611 			acpi_lpss_link_supplier(&pdev->dev, link);
612 	}
613 }
614 
615 static int acpi_lpss_create_device(struct acpi_device *adev,
616 				   const struct acpi_device_id *id)
617 {
618 	const struct lpss_device_desc *dev_desc;
619 	struct lpss_private_data *pdata;
620 	struct resource_entry *rentry;
621 	struct list_head resource_list;
622 	struct platform_device *pdev;
623 	int ret;
624 
625 	dev_desc = (const struct lpss_device_desc *)id->driver_data;
626 	if (!dev_desc)
627 		return -EINVAL;
628 
629 	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
630 	if (!pdata)
631 		return -ENOMEM;
632 
633 	INIT_LIST_HEAD(&resource_list);
634 	ret = acpi_dev_get_memory_resources(adev, &resource_list);
635 	if (ret < 0)
636 		goto err_out;
637 
638 	rentry = list_first_entry_or_null(&resource_list, struct resource_entry, node);
639 	if (rentry) {
640 		if (dev_desc->prv_size_override)
641 			pdata->mmio_size = dev_desc->prv_size_override;
642 		else
643 			pdata->mmio_size = resource_size(rentry->res);
644 		pdata->mmio_base = ioremap(rentry->res->start, pdata->mmio_size);
645 	}
646 
647 	acpi_dev_free_resource_list(&resource_list);
648 
649 	if (!pdata->mmio_base) {
650 		/* Avoid acpi_bus_attach() instantiating a pdev for this dev. */
651 		adev->pnp.type.platform_id = 0;
652 		goto out_free;
653 	}
654 
655 	pdata->adev = adev;
656 	pdata->dev_desc = dev_desc;
657 
658 	if (dev_desc->setup)
659 		dev_desc->setup(pdata);
660 
661 	if (dev_desc->flags & LPSS_CLK) {
662 		ret = register_device_clock(adev, pdata);
663 		if (ret)
664 			goto out_free;
665 	}
666 
667 	/*
668 	 * This works around a known issue in ACPI tables where LPSS devices
669 	 * have _PS0 and _PS3 without _PSC (and no power resources), so
670 	 * acpi_bus_init_power() will assume that the BIOS has put them into D0.
671 	 */
672 	acpi_device_fix_up_power(adev);
673 
674 	adev->driver_data = pdata;
675 	pdev = acpi_create_platform_device(adev, dev_desc->properties);
676 	if (IS_ERR_OR_NULL(pdev)) {
677 		adev->driver_data = NULL;
678 		ret = PTR_ERR(pdev);
679 		goto err_out;
680 	}
681 
682 	acpi_lpss_create_device_links(adev, pdev);
683 	return 1;
684 
685 out_free:
686 	/* Skip the device, but continue the namespace scan */
687 	ret = 0;
688 err_out:
689 	kfree(pdata);
690 	return ret;
691 }
692 
693 static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
694 {
695 	return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
696 }
697 
698 static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
699 			     unsigned int reg)
700 {
701 	writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
702 }
703 
704 static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
705 {
706 	struct acpi_device *adev = ACPI_COMPANION(dev);
707 	struct lpss_private_data *pdata;
708 	unsigned long flags;
709 	int ret;
710 
711 	if (WARN_ON(!adev))
712 		return -ENODEV;
713 
714 	spin_lock_irqsave(&dev->power.lock, flags);
715 	if (pm_runtime_suspended(dev)) {
716 		ret = -EAGAIN;
717 		goto out;
718 	}
719 	pdata = acpi_driver_data(adev);
720 	if (WARN_ON(!pdata || !pdata->mmio_base)) {
721 		ret = -ENODEV;
722 		goto out;
723 	}
724 	*val = __lpss_reg_read(pdata, reg);
725 	ret = 0;
726 
727  out:
728 	spin_unlock_irqrestore(&dev->power.lock, flags);
729 	return ret;
730 }
731 
732 static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
733 			     char *buf)
734 {
735 	u32 ltr_value = 0;
736 	unsigned int reg;
737 	int ret;
738 
739 	reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
740 	ret = lpss_reg_read(dev, reg, &ltr_value);
741 	if (ret)
742 		return ret;
743 
744 	return sysfs_emit(buf, "%08x\n", ltr_value);
745 }
746 
747 static ssize_t lpss_ltr_mode_show(struct device *dev,
748 				  struct device_attribute *attr, char *buf)
749 {
750 	u32 ltr_mode = 0;
751 	char *outstr;
752 	int ret;
753 
754 	ret = lpss_reg_read(dev, LPSS_GENERAL, &ltr_mode);
755 	if (ret)
756 		return ret;
757 
758 	outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
759 	return sprintf(buf, "%s\n", outstr);
760 }
761 
762 static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
763 static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
764 static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
765 
766 static struct attribute *lpss_attrs[] = {
767 	&dev_attr_auto_ltr.attr,
768 	&dev_attr_sw_ltr.attr,
769 	&dev_attr_ltr_mode.attr,
770 	NULL,
771 };
772 
773 static const struct attribute_group lpss_attr_group = {
774 	.attrs = lpss_attrs,
775 	.name = "lpss_ltr",
776 };
777 
778 static void acpi_lpss_set_ltr(struct device *dev, s32 val)
779 {
780 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
781 	u32 ltr_mode, ltr_val;
782 
783 	ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
784 	if (val < 0) {
785 		if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
786 			ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
787 			__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
788 		}
789 		return;
790 	}
791 	ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
792 	if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
793 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
794 		val = LPSS_LTR_MAX_VAL;
795 	} else if (val > LPSS_LTR_MAX_VAL) {
796 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
797 		val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
798 	} else {
799 		ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
800 	}
801 	ltr_val |= val;
802 	__lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
803 	if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
804 		ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
805 		__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
806 	}
807 }
808 
809 #ifdef CONFIG_PM
810 /**
811  * acpi_lpss_save_ctx() - Save the private registers of LPSS device
812  * @dev: LPSS device
813  * @pdata: pointer to the private data of the LPSS device
814  *
815  * Most LPSS devices have private registers which may loose their context when
816  * the device is powered down. acpi_lpss_save_ctx() saves those registers into
817  * prv_reg_ctx array.
818  */
819 static void acpi_lpss_save_ctx(struct device *dev,
820 			       struct lpss_private_data *pdata)
821 {
822 	unsigned int i;
823 
824 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
825 		unsigned long offset = i * sizeof(u32);
826 
827 		pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
828 		dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
829 			pdata->prv_reg_ctx[i], offset);
830 	}
831 }
832 
833 /**
834  * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
835  * @dev: LPSS device
836  * @pdata: pointer to the private data of the LPSS device
837  *
838  * Restores the registers that were previously stored with acpi_lpss_save_ctx().
839  */
840 static void acpi_lpss_restore_ctx(struct device *dev,
841 				  struct lpss_private_data *pdata)
842 {
843 	unsigned int i;
844 
845 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
846 		unsigned long offset = i * sizeof(u32);
847 
848 		__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
849 		dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
850 			pdata->prv_reg_ctx[i], offset);
851 	}
852 }
853 
854 static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
855 {
856 	/*
857 	 * The following delay is needed or the subsequent write operations may
858 	 * fail. The LPSS devices are actually PCI devices and the PCI spec
859 	 * expects 10ms delay before the device can be accessed after D3 to D0
860 	 * transition. However some platforms like BSW does not need this delay.
861 	 */
862 	unsigned int delay = 10;	/* default 10ms delay */
863 
864 	if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)
865 		delay = 0;
866 
867 	msleep(delay);
868 }
869 
870 static int acpi_lpss_activate(struct device *dev)
871 {
872 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
873 	int ret;
874 
875 	ret = acpi_dev_resume(dev);
876 	if (ret)
877 		return ret;
878 
879 	acpi_lpss_d3_to_d0_delay(pdata);
880 
881 	/*
882 	 * This is called only on ->probe() stage where a device is either in
883 	 * known state defined by BIOS or most likely powered off. Due to this
884 	 * we have to deassert reset line to be sure that ->probe() will
885 	 * recognize the device.
886 	 */
887 	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
888 		lpss_deassert_reset(pdata);
889 
890 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX_ONCE)
891 		acpi_lpss_save_ctx(dev, pdata);
892 
893 	return 0;
894 }
895 
896 static void acpi_lpss_dismiss(struct device *dev)
897 {
898 	acpi_dev_suspend(dev, false);
899 }
900 
901 /* IOSF SB for LPSS island */
902 #define LPSS_IOSF_UNIT_LPIOEP		0xA0
903 #define LPSS_IOSF_UNIT_LPIO1		0xAB
904 #define LPSS_IOSF_UNIT_LPIO2		0xAC
905 
906 #define LPSS_IOSF_PMCSR			0x84
907 #define LPSS_PMCSR_D0			0
908 #define LPSS_PMCSR_D3hot		3
909 #define LPSS_PMCSR_Dx_MASK		GENMASK(1, 0)
910 
911 #define LPSS_IOSF_GPIODEF0		0x154
912 #define LPSS_GPIODEF0_DMA1_D3		BIT(2)
913 #define LPSS_GPIODEF0_DMA2_D3		BIT(3)
914 #define LPSS_GPIODEF0_DMA_D3_MASK	GENMASK(3, 2)
915 #define LPSS_GPIODEF0_DMA_LLP		BIT(13)
916 
917 static DEFINE_MUTEX(lpss_iosf_mutex);
918 static bool lpss_iosf_d3_entered = true;
919 
920 static void lpss_iosf_enter_d3_state(void)
921 {
922 	u32 value1 = 0;
923 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
924 	u32 value2 = LPSS_PMCSR_D3hot;
925 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
926 	/*
927 	 * PMC provides an information about actual status of the LPSS devices.
928 	 * Here we read the values related to LPSS power island, i.e. LPSS
929 	 * devices, excluding both LPSS DMA controllers, along with SCC domain.
930 	 */
931 	u32 func_dis, d3_sts_0, pmc_status;
932 	int ret;
933 
934 	ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);
935 	if (ret)
936 		return;
937 
938 	mutex_lock(&lpss_iosf_mutex);
939 
940 	ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);
941 	if (ret)
942 		goto exit;
943 
944 	/*
945 	 * Get the status of entire LPSS power island per device basis.
946 	 * Shutdown both LPSS DMA controllers if and only if all other devices
947 	 * are already in D3hot.
948 	 */
949 	pmc_status = (~(d3_sts_0 | func_dis)) & pmc_atom_d3_mask;
950 	if (pmc_status)
951 		goto exit;
952 
953 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
954 			LPSS_IOSF_PMCSR, value2, mask2);
955 
956 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
957 			LPSS_IOSF_PMCSR, value2, mask2);
958 
959 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
960 			LPSS_IOSF_GPIODEF0, value1, mask1);
961 
962 	lpss_iosf_d3_entered = true;
963 
964 exit:
965 	mutex_unlock(&lpss_iosf_mutex);
966 }
967 
968 static void lpss_iosf_exit_d3_state(void)
969 {
970 	u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 |
971 		     LPSS_GPIODEF0_DMA_LLP;
972 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
973 	u32 value2 = LPSS_PMCSR_D0;
974 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
975 
976 	mutex_lock(&lpss_iosf_mutex);
977 
978 	if (!lpss_iosf_d3_entered)
979 		goto exit;
980 
981 	lpss_iosf_d3_entered = false;
982 
983 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
984 			LPSS_IOSF_GPIODEF0, value1, mask1);
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_LPIO1, MBI_CFG_WRITE,
990 			LPSS_IOSF_PMCSR, value2, mask2);
991 
992 exit:
993 	mutex_unlock(&lpss_iosf_mutex);
994 }
995 
996 static int acpi_lpss_suspend(struct device *dev, bool wakeup)
997 {
998 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
999 	int ret;
1000 
1001 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
1002 		acpi_lpss_save_ctx(dev, pdata);
1003 
1004 	ret = acpi_dev_suspend(dev, wakeup);
1005 
1006 	/*
1007 	 * This call must be last in the sequence, otherwise PMC will return
1008 	 * wrong status for devices being about to be powered off. See
1009 	 * lpss_iosf_enter_d3_state() for further information.
1010 	 */
1011 	if (acpi_target_system_state() == ACPI_STATE_S0 &&
1012 	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1013 		lpss_iosf_enter_d3_state();
1014 
1015 	return ret;
1016 }
1017 
1018 static int acpi_lpss_resume(struct device *dev)
1019 {
1020 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1021 	int ret;
1022 
1023 	/*
1024 	 * This call is kept first to be in symmetry with
1025 	 * acpi_lpss_runtime_suspend() one.
1026 	 */
1027 	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1028 		lpss_iosf_exit_d3_state();
1029 
1030 	ret = acpi_dev_resume(dev);
1031 	if (ret)
1032 		return ret;
1033 
1034 	acpi_lpss_d3_to_d0_delay(pdata);
1035 
1036 	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
1037 		acpi_lpss_restore_ctx(dev, pdata);
1038 
1039 	return 0;
1040 }
1041 
1042 #ifdef CONFIG_PM_SLEEP
1043 static int acpi_lpss_do_suspend_late(struct device *dev)
1044 {
1045 	int ret;
1046 
1047 	if (dev_pm_skip_suspend(dev))
1048 		return 0;
1049 
1050 	ret = pm_generic_suspend_late(dev);
1051 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1052 }
1053 
1054 static int acpi_lpss_suspend_late(struct device *dev)
1055 {
1056 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1057 
1058 	if (pdata->dev_desc->resume_from_noirq)
1059 		return 0;
1060 
1061 	return acpi_lpss_do_suspend_late(dev);
1062 }
1063 
1064 static int acpi_lpss_suspend_noirq(struct device *dev)
1065 {
1066 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1067 	int ret;
1068 
1069 	if (pdata->dev_desc->resume_from_noirq) {
1070 		/*
1071 		 * The driver's ->suspend_late callback will be invoked by
1072 		 * acpi_lpss_do_suspend_late(), with the assumption that the
1073 		 * driver really wanted to run that code in ->suspend_noirq, but
1074 		 * it could not run after acpi_dev_suspend() and the driver
1075 		 * expected the latter to be called in the "late" phase.
1076 		 */
1077 		ret = acpi_lpss_do_suspend_late(dev);
1078 		if (ret)
1079 			return ret;
1080 	}
1081 
1082 	return acpi_subsys_suspend_noirq(dev);
1083 }
1084 
1085 static int acpi_lpss_do_resume_early(struct device *dev)
1086 {
1087 	int ret = acpi_lpss_resume(dev);
1088 
1089 	return ret ? ret : pm_generic_resume_early(dev);
1090 }
1091 
1092 static int acpi_lpss_resume_early(struct device *dev)
1093 {
1094 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1095 
1096 	if (pdata->dev_desc->resume_from_noirq)
1097 		return 0;
1098 
1099 	if (dev_pm_skip_resume(dev))
1100 		return 0;
1101 
1102 	return acpi_lpss_do_resume_early(dev);
1103 }
1104 
1105 static int acpi_lpss_resume_noirq(struct device *dev)
1106 {
1107 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1108 	int ret;
1109 
1110 	/* Follow acpi_subsys_resume_noirq(). */
1111 	if (dev_pm_skip_resume(dev))
1112 		return 0;
1113 
1114 	ret = pm_generic_resume_noirq(dev);
1115 	if (ret)
1116 		return ret;
1117 
1118 	if (!pdata->dev_desc->resume_from_noirq)
1119 		return 0;
1120 
1121 	/*
1122 	 * The driver's ->resume_early callback will be invoked by
1123 	 * acpi_lpss_do_resume_early(), with the assumption that the driver
1124 	 * really wanted to run that code in ->resume_noirq, but it could not
1125 	 * run before acpi_dev_resume() and the driver expected the latter to be
1126 	 * called in the "early" phase.
1127 	 */
1128 	return acpi_lpss_do_resume_early(dev);
1129 }
1130 
1131 static int acpi_lpss_do_restore_early(struct device *dev)
1132 {
1133 	int ret = acpi_lpss_resume(dev);
1134 
1135 	return ret ? ret : pm_generic_restore_early(dev);
1136 }
1137 
1138 static int acpi_lpss_restore_early(struct device *dev)
1139 {
1140 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1141 
1142 	if (pdata->dev_desc->resume_from_noirq)
1143 		return 0;
1144 
1145 	return acpi_lpss_do_restore_early(dev);
1146 }
1147 
1148 static int acpi_lpss_restore_noirq(struct device *dev)
1149 {
1150 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1151 	int ret;
1152 
1153 	ret = pm_generic_restore_noirq(dev);
1154 	if (ret)
1155 		return ret;
1156 
1157 	if (!pdata->dev_desc->resume_from_noirq)
1158 		return 0;
1159 
1160 	/* This is analogous to what happens in acpi_lpss_resume_noirq(). */
1161 	return acpi_lpss_do_restore_early(dev);
1162 }
1163 
1164 static int acpi_lpss_do_poweroff_late(struct device *dev)
1165 {
1166 	int ret = pm_generic_poweroff_late(dev);
1167 
1168 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1169 }
1170 
1171 static int acpi_lpss_poweroff_late(struct device *dev)
1172 {
1173 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1174 
1175 	if (dev_pm_skip_suspend(dev))
1176 		return 0;
1177 
1178 	if (pdata->dev_desc->resume_from_noirq)
1179 		return 0;
1180 
1181 	return acpi_lpss_do_poweroff_late(dev);
1182 }
1183 
1184 static int acpi_lpss_poweroff_noirq(struct device *dev)
1185 {
1186 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1187 
1188 	if (dev_pm_skip_suspend(dev))
1189 		return 0;
1190 
1191 	if (pdata->dev_desc->resume_from_noirq) {
1192 		/* This is analogous to the acpi_lpss_suspend_noirq() case. */
1193 		int ret = acpi_lpss_do_poweroff_late(dev);
1194 
1195 		if (ret)
1196 			return ret;
1197 	}
1198 
1199 	return pm_generic_poweroff_noirq(dev);
1200 }
1201 #endif /* CONFIG_PM_SLEEP */
1202 
1203 static int acpi_lpss_runtime_suspend(struct device *dev)
1204 {
1205 	int ret = pm_generic_runtime_suspend(dev);
1206 
1207 	return ret ? ret : acpi_lpss_suspend(dev, true);
1208 }
1209 
1210 static int acpi_lpss_runtime_resume(struct device *dev)
1211 {
1212 	int ret = acpi_lpss_resume(dev);
1213 
1214 	return ret ? ret : pm_generic_runtime_resume(dev);
1215 }
1216 #endif /* CONFIG_PM */
1217 
1218 static struct dev_pm_domain acpi_lpss_pm_domain = {
1219 #ifdef CONFIG_PM
1220 	.activate = acpi_lpss_activate,
1221 	.dismiss = acpi_lpss_dismiss,
1222 #endif
1223 	.ops = {
1224 #ifdef CONFIG_PM
1225 #ifdef CONFIG_PM_SLEEP
1226 		.prepare = acpi_subsys_prepare,
1227 		.complete = acpi_subsys_complete,
1228 		.suspend = acpi_subsys_suspend,
1229 		.suspend_late = acpi_lpss_suspend_late,
1230 		.suspend_noirq = acpi_lpss_suspend_noirq,
1231 		.resume_noirq = acpi_lpss_resume_noirq,
1232 		.resume_early = acpi_lpss_resume_early,
1233 		.freeze = acpi_subsys_freeze,
1234 		.poweroff = acpi_subsys_poweroff,
1235 		.poweroff_late = acpi_lpss_poweroff_late,
1236 		.poweroff_noirq = acpi_lpss_poweroff_noirq,
1237 		.restore_noirq = acpi_lpss_restore_noirq,
1238 		.restore_early = acpi_lpss_restore_early,
1239 #endif
1240 		.runtime_suspend = acpi_lpss_runtime_suspend,
1241 		.runtime_resume = acpi_lpss_runtime_resume,
1242 #endif
1243 	},
1244 };
1245 
1246 static int acpi_lpss_platform_notify(struct notifier_block *nb,
1247 				     unsigned long action, void *data)
1248 {
1249 	struct platform_device *pdev = to_platform_device(data);
1250 	struct lpss_private_data *pdata;
1251 	struct acpi_device *adev;
1252 	const struct acpi_device_id *id;
1253 
1254 	id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
1255 	if (!id || !id->driver_data)
1256 		return 0;
1257 
1258 	adev = ACPI_COMPANION(&pdev->dev);
1259 	if (!adev)
1260 		return 0;
1261 
1262 	pdata = acpi_driver_data(adev);
1263 	if (!pdata)
1264 		return 0;
1265 
1266 	if (pdata->mmio_base &&
1267 	    pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
1268 		dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
1269 		return 0;
1270 	}
1271 
1272 	switch (action) {
1273 	case BUS_NOTIFY_BIND_DRIVER:
1274 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1275 		break;
1276 	case BUS_NOTIFY_DRIVER_NOT_BOUND:
1277 	case BUS_NOTIFY_UNBOUND_DRIVER:
1278 		dev_pm_domain_set(&pdev->dev, NULL);
1279 		break;
1280 	case BUS_NOTIFY_ADD_DEVICE:
1281 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1282 		if (pdata->dev_desc->flags & LPSS_LTR)
1283 			return sysfs_create_group(&pdev->dev.kobj,
1284 						  &lpss_attr_group);
1285 		break;
1286 	case BUS_NOTIFY_DEL_DEVICE:
1287 		if (pdata->dev_desc->flags & LPSS_LTR)
1288 			sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
1289 		dev_pm_domain_set(&pdev->dev, NULL);
1290 		break;
1291 	default:
1292 		break;
1293 	}
1294 
1295 	return 0;
1296 }
1297 
1298 static struct notifier_block acpi_lpss_nb = {
1299 	.notifier_call = acpi_lpss_platform_notify,
1300 };
1301 
1302 static void acpi_lpss_bind(struct device *dev)
1303 {
1304 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1305 
1306 	if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
1307 		return;
1308 
1309 	if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
1310 		dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
1311 	else
1312 		dev_err(dev, "MMIO size insufficient to access LTR\n");
1313 }
1314 
1315 static void acpi_lpss_unbind(struct device *dev)
1316 {
1317 	dev->power.set_latency_tolerance = NULL;
1318 }
1319 
1320 static struct acpi_scan_handler lpss_handler = {
1321 	.ids = acpi_lpss_device_ids,
1322 	.attach = acpi_lpss_create_device,
1323 	.bind = acpi_lpss_bind,
1324 	.unbind = acpi_lpss_unbind,
1325 };
1326 
1327 void __init acpi_lpss_init(void)
1328 {
1329 	const struct x86_cpu_id *id;
1330 	int ret;
1331 
1332 	ret = lpss_atom_clk_init();
1333 	if (ret)
1334 		return;
1335 
1336 	id = x86_match_cpu(lpss_cpu_ids);
1337 	if (id)
1338 		lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;
1339 
1340 	bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
1341 	acpi_scan_add_handler(&lpss_handler);
1342 }
1343 
1344 #else
1345 
1346 static struct acpi_scan_handler lpss_handler = {
1347 	.ids = acpi_lpss_device_ids,
1348 };
1349 
1350 void __init acpi_lpss_init(void)
1351 {
1352 	acpi_scan_add_handler(&lpss_handler);
1353 }
1354 
1355 #endif /* CONFIG_X86_INTEL_LPSS */
1356