xref: /openbmc/linux/drivers/acpi/acpi_lpss.c (revision 9470114d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ACPI support for Intel Lynxpoint LPSS.
4  *
5  * Copyright (C) 2013, Intel Corporation
6  * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
7  *          Rafael J. Wysocki <rafael.j.wysocki@intel.com>
8  */
9 
10 #include <linux/acpi.h>
11 #include <linux/clkdev.h>
12 #include <linux/clk-provider.h>
13 #include <linux/dmi.h>
14 #include <linux/err.h>
15 #include <linux/io.h>
16 #include <linux/mutex.h>
17 #include <linux/pci.h>
18 #include <linux/platform_device.h>
19 #include <linux/platform_data/x86/clk-lpss.h>
20 #include <linux/platform_data/x86/pmc_atom.h>
21 #include <linux/pm_domain.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/pwm.h>
24 #include <linux/pxa2xx_ssp.h>
25 #include <linux/suspend.h>
26 #include <linux/delay.h>
27 
28 #include "internal.h"
29 
30 #ifdef CONFIG_X86_INTEL_LPSS
31 
32 #include <asm/cpu_device_id.h>
33 #include <asm/intel-family.h>
34 #include <asm/iosf_mbi.h>
35 
36 #define LPSS_ADDR(desc) ((unsigned long)&desc)
37 
38 #define LPSS_CLK_SIZE	0x04
39 #define LPSS_LTR_SIZE	0x18
40 
41 /* Offsets relative to LPSS_PRIVATE_OFFSET */
42 #define LPSS_CLK_DIVIDER_DEF_MASK	(BIT(1) | BIT(16))
43 #define LPSS_RESETS			0x04
44 #define LPSS_RESETS_RESET_FUNC		BIT(0)
45 #define LPSS_RESETS_RESET_APB		BIT(1)
46 #define LPSS_GENERAL			0x08
47 #define LPSS_GENERAL_LTR_MODE_SW	BIT(2)
48 #define LPSS_GENERAL_UART_RTS_OVRD	BIT(3)
49 #define LPSS_SW_LTR			0x10
50 #define LPSS_AUTO_LTR			0x14
51 #define LPSS_LTR_SNOOP_REQ		BIT(15)
52 #define LPSS_LTR_SNOOP_MASK		0x0000FFFF
53 #define LPSS_LTR_SNOOP_LAT_1US		0x800
54 #define LPSS_LTR_SNOOP_LAT_32US		0xC00
55 #define LPSS_LTR_SNOOP_LAT_SHIFT	5
56 #define LPSS_LTR_SNOOP_LAT_CUTOFF	3000
57 #define LPSS_LTR_MAX_VAL		0x3FF
58 #define LPSS_TX_INT			0x20
59 #define LPSS_TX_INT_MASK		BIT(1)
60 
61 #define LPSS_PRV_REG_COUNT		9
62 
63 /* LPSS Flags */
64 #define LPSS_CLK			BIT(0)
65 #define LPSS_CLK_GATE			BIT(1)
66 #define LPSS_CLK_DIVIDER		BIT(2)
67 #define LPSS_LTR			BIT(3)
68 #define LPSS_SAVE_CTX			BIT(4)
69 /*
70  * For some devices the DSDT AML code for another device turns off the device
71  * before our suspend handler runs, causing us to read/save all 1-s (0xffffffff)
72  * as ctx register values.
73  * Luckily these devices always use the same ctx register values, so we can
74  * work around this by saving the ctx registers once on activation.
75  */
76 #define LPSS_SAVE_CTX_ONCE		BIT(5)
77 #define LPSS_NO_D3_DELAY		BIT(6)
78 
79 struct lpss_private_data;
80 
81 struct lpss_device_desc {
82 	unsigned int flags;
83 	const char *clk_con_id;
84 	unsigned int prv_offset;
85 	size_t prv_size_override;
86 	const struct property_entry *properties;
87 	void (*setup)(struct lpss_private_data *pdata);
88 	bool resume_from_noirq;
89 };
90 
91 static const struct lpss_device_desc lpss_dma_desc = {
92 	.flags = LPSS_CLK,
93 };
94 
95 struct lpss_private_data {
96 	struct acpi_device *adev;
97 	void __iomem *mmio_base;
98 	resource_size_t mmio_size;
99 	unsigned int fixed_clk_rate;
100 	struct clk *clk;
101 	const struct lpss_device_desc *dev_desc;
102 	u32 prv_reg_ctx[LPSS_PRV_REG_COUNT];
103 };
104 
105 /* Devices which need to be in D3 before lpss_iosf_enter_d3_state() proceeds */
106 static u32 pmc_atom_d3_mask = 0xfe000ffe;
107 
108 /* LPSS run time quirks */
109 static unsigned int lpss_quirks;
110 
111 /*
112  * LPSS_QUIRK_ALWAYS_POWER_ON: override power state for LPSS DMA device.
113  *
114  * The LPSS DMA controller has neither _PS0 nor _PS3 method. Moreover
115  * it can be powered off automatically whenever the last LPSS device goes down.
116  * In case of no power any access to the DMA controller will hang the system.
117  * The behaviour is reproduced on some HP laptops based on Intel BayTrail as
118  * well as on ASuS T100TA transformer.
119  *
120  * This quirk overrides power state of entire LPSS island to keep DMA powered
121  * on whenever we have at least one other device in use.
122  */
123 #define LPSS_QUIRK_ALWAYS_POWER_ON	BIT(0)
124 
125 /* UART Component Parameter Register */
126 #define LPSS_UART_CPR			0xF4
127 #define LPSS_UART_CPR_AFCE		BIT(4)
128 
129 static void lpss_uart_setup(struct lpss_private_data *pdata)
130 {
131 	unsigned int offset;
132 	u32 val;
133 
134 	offset = pdata->dev_desc->prv_offset + LPSS_TX_INT;
135 	val = readl(pdata->mmio_base + offset);
136 	writel(val | LPSS_TX_INT_MASK, pdata->mmio_base + offset);
137 
138 	val = readl(pdata->mmio_base + LPSS_UART_CPR);
139 	if (!(val & LPSS_UART_CPR_AFCE)) {
140 		offset = pdata->dev_desc->prv_offset + LPSS_GENERAL;
141 		val = readl(pdata->mmio_base + offset);
142 		val |= LPSS_GENERAL_UART_RTS_OVRD;
143 		writel(val, pdata->mmio_base + offset);
144 	}
145 }
146 
147 static void lpss_deassert_reset(struct lpss_private_data *pdata)
148 {
149 	unsigned int offset;
150 	u32 val;
151 
152 	offset = pdata->dev_desc->prv_offset + LPSS_RESETS;
153 	val = readl(pdata->mmio_base + offset);
154 	val |= LPSS_RESETS_RESET_APB | LPSS_RESETS_RESET_FUNC;
155 	writel(val, pdata->mmio_base + offset);
156 }
157 
158 /*
159  * BYT PWM used for backlight control by the i915 driver on systems without
160  * the Crystal Cove PMIC.
161  */
162 static struct pwm_lookup byt_pwm_lookup[] = {
163 	PWM_LOOKUP_WITH_MODULE("80860F09:00", 0, "0000:00:02.0",
164 			       "pwm_soc_backlight", 0, PWM_POLARITY_NORMAL,
165 			       "pwm-lpss-platform"),
166 };
167 
168 static void byt_pwm_setup(struct lpss_private_data *pdata)
169 {
170 	u64 uid;
171 
172 	/* Only call pwm_add_table for the first PWM controller */
173 	if (acpi_dev_uid_to_integer(pdata->adev, &uid) || uid != 1)
174 		return;
175 
176 	pwm_add_table(byt_pwm_lookup, ARRAY_SIZE(byt_pwm_lookup));
177 }
178 
179 #define LPSS_I2C_ENABLE			0x6c
180 
181 static void byt_i2c_setup(struct lpss_private_data *pdata)
182 {
183 	acpi_handle handle = pdata->adev->handle;
184 	unsigned long long shared_host = 0;
185 	acpi_status status;
186 	u64 uid;
187 
188 	/* Expected to always be successfull, but better safe then sorry */
189 	if (!acpi_dev_uid_to_integer(pdata->adev, &uid) && uid) {
190 		/* Detect I2C bus shared with PUNIT and ignore its d3 status */
191 		status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host);
192 		if (ACPI_SUCCESS(status) && shared_host)
193 			pmc_atom_d3_mask &= ~(BIT_LPSS2_F1_I2C1 << (uid - 1));
194 	}
195 
196 	lpss_deassert_reset(pdata);
197 
198 	if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset))
199 		pdata->fixed_clk_rate = 133000000;
200 
201 	writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
202 }
203 
204 /*
205  * BSW PWM1 is used for backlight control by the i915 driver
206  * BSW PWM2 is used for backlight control for fixed (etched into the glass)
207  * touch controls on some models. These touch-controls have specialized
208  * drivers which know they need the "pwm_soc_lpss_2" con-id.
209  */
210 static struct pwm_lookup bsw_pwm_lookup[] = {
211 	PWM_LOOKUP_WITH_MODULE("80862288:00", 0, "0000:00:02.0",
212 			       "pwm_soc_backlight", 0, PWM_POLARITY_NORMAL,
213 			       "pwm-lpss-platform"),
214 	PWM_LOOKUP_WITH_MODULE("80862289:00", 0, NULL,
215 			       "pwm_soc_lpss_2", 0, PWM_POLARITY_NORMAL,
216 			       "pwm-lpss-platform"),
217 };
218 
219 static void bsw_pwm_setup(struct lpss_private_data *pdata)
220 {
221 	u64 uid;
222 
223 	/* Only call pwm_add_table for the first PWM controller */
224 	if (acpi_dev_uid_to_integer(pdata->adev, &uid) || uid != 1)
225 		return;
226 
227 	pwm_add_table(bsw_pwm_lookup, ARRAY_SIZE(bsw_pwm_lookup));
228 }
229 
230 static const struct property_entry lpt_spi_properties[] = {
231 	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_LPT_SSP),
232 	{ }
233 };
234 
235 static const struct lpss_device_desc lpt_spi_dev_desc = {
236 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR
237 			| LPSS_SAVE_CTX,
238 	.prv_offset = 0x800,
239 	.properties = lpt_spi_properties,
240 };
241 
242 static const struct lpss_device_desc lpt_i2c_dev_desc = {
243 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR | LPSS_SAVE_CTX,
244 	.prv_offset = 0x800,
245 };
246 
247 static struct property_entry uart_properties[] = {
248 	PROPERTY_ENTRY_U32("reg-io-width", 4),
249 	PROPERTY_ENTRY_U32("reg-shift", 2),
250 	PROPERTY_ENTRY_BOOL("snps,uart-16550-compatible"),
251 	{ },
252 };
253 
254 static const struct lpss_device_desc lpt_uart_dev_desc = {
255 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR
256 			| LPSS_SAVE_CTX,
257 	.clk_con_id = "baudclk",
258 	.prv_offset = 0x800,
259 	.setup = lpss_uart_setup,
260 	.properties = uart_properties,
261 };
262 
263 static const struct lpss_device_desc lpt_sdio_dev_desc = {
264 	.flags = LPSS_LTR,
265 	.prv_offset = 0x1000,
266 	.prv_size_override = 0x1018,
267 };
268 
269 static const struct lpss_device_desc byt_pwm_dev_desc = {
270 	.flags = LPSS_SAVE_CTX,
271 	.prv_offset = 0x800,
272 	.setup = byt_pwm_setup,
273 };
274 
275 static const struct lpss_device_desc bsw_pwm_dev_desc = {
276 	.flags = LPSS_SAVE_CTX_ONCE | LPSS_NO_D3_DELAY,
277 	.prv_offset = 0x800,
278 	.setup = bsw_pwm_setup,
279 	.resume_from_noirq = true,
280 };
281 
282 static const struct lpss_device_desc bsw_pwm2_dev_desc = {
283 	.flags = LPSS_SAVE_CTX_ONCE | LPSS_NO_D3_DELAY,
284 	.prv_offset = 0x800,
285 	.resume_from_noirq = true,
286 };
287 
288 static const struct lpss_device_desc byt_uart_dev_desc = {
289 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
290 	.clk_con_id = "baudclk",
291 	.prv_offset = 0x800,
292 	.setup = lpss_uart_setup,
293 	.properties = uart_properties,
294 };
295 
296 static const struct lpss_device_desc bsw_uart_dev_desc = {
297 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
298 			| LPSS_NO_D3_DELAY,
299 	.clk_con_id = "baudclk",
300 	.prv_offset = 0x800,
301 	.setup = lpss_uart_setup,
302 	.properties = uart_properties,
303 };
304 
305 static const struct property_entry byt_spi_properties[] = {
306 	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_BYT_SSP),
307 	{ }
308 };
309 
310 static const struct lpss_device_desc byt_spi_dev_desc = {
311 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
312 	.prv_offset = 0x400,
313 	.properties = byt_spi_properties,
314 };
315 
316 static const struct lpss_device_desc byt_sdio_dev_desc = {
317 	.flags = LPSS_CLK,
318 };
319 
320 static const struct lpss_device_desc byt_i2c_dev_desc = {
321 	.flags = LPSS_CLK | LPSS_SAVE_CTX,
322 	.prv_offset = 0x800,
323 	.setup = byt_i2c_setup,
324 	.resume_from_noirq = true,
325 };
326 
327 static const struct lpss_device_desc bsw_i2c_dev_desc = {
328 	.flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
329 	.prv_offset = 0x800,
330 	.setup = byt_i2c_setup,
331 	.resume_from_noirq = true,
332 };
333 
334 static const struct property_entry bsw_spi_properties[] = {
335 	PROPERTY_ENTRY_U32("intel,spi-pxa2xx-type", LPSS_BSW_SSP),
336 	{ }
337 };
338 
339 static const struct lpss_device_desc bsw_spi_dev_desc = {
340 	.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
341 			| LPSS_NO_D3_DELAY,
342 	.prv_offset = 0x400,
343 	.setup = lpss_deassert_reset,
344 	.properties = bsw_spi_properties,
345 };
346 
347 static const struct x86_cpu_id lpss_cpu_ids[] = {
348 	X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT,	NULL),
349 	X86_MATCH_INTEL_FAM6_MODEL(ATOM_AIRMONT,	NULL),
350 	{}
351 };
352 
353 #else
354 
355 #define LPSS_ADDR(desc) (0UL)
356 
357 #endif /* CONFIG_X86_INTEL_LPSS */
358 
359 static const struct acpi_device_id acpi_lpss_device_ids[] = {
360 	/* Generic LPSS devices */
361 	{ "INTL9C60", LPSS_ADDR(lpss_dma_desc) },
362 
363 	/* Lynxpoint LPSS devices */
364 	{ "INT33C0", LPSS_ADDR(lpt_spi_dev_desc) },
365 	{ "INT33C1", LPSS_ADDR(lpt_spi_dev_desc) },
366 	{ "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },
367 	{ "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },
368 	{ "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },
369 	{ "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },
370 	{ "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },
371 	{ "INT33C7", },
372 
373 	/* BayTrail LPSS devices */
374 	{ "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },
375 	{ "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },
376 	{ "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },
377 	{ "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },
378 	{ "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },
379 	{ "INT33B2", },
380 	{ "INT33FC", },
381 
382 	/* Braswell LPSS devices */
383 	{ "80862286", LPSS_ADDR(lpss_dma_desc) },
384 	{ "80862288", LPSS_ADDR(bsw_pwm_dev_desc) },
385 	{ "80862289", LPSS_ADDR(bsw_pwm2_dev_desc) },
386 	{ "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },
387 	{ "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },
388 	{ "808622C0", LPSS_ADDR(lpss_dma_desc) },
389 	{ "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) },
390 
391 	/* Broadwell LPSS devices */
392 	{ "INT3430", LPSS_ADDR(lpt_spi_dev_desc) },
393 	{ "INT3431", LPSS_ADDR(lpt_spi_dev_desc) },
394 	{ "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },
395 	{ "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },
396 	{ "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },
397 	{ "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },
398 	{ "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },
399 	{ "INT3437", },
400 
401 	/* Wildcat Point LPSS devices */
402 	{ "INT3438", LPSS_ADDR(lpt_spi_dev_desc) },
403 
404 	{ }
405 };
406 
407 #ifdef CONFIG_X86_INTEL_LPSS
408 
409 /* LPSS main clock device. */
410 static struct platform_device *lpss_clk_dev;
411 
412 static inline void lpt_register_clock_device(void)
413 {
414 	lpss_clk_dev = platform_device_register_simple("clk-lpss-atom",
415 						       PLATFORM_DEVID_NONE,
416 						       NULL, 0);
417 }
418 
419 static int register_device_clock(struct acpi_device *adev,
420 				 struct lpss_private_data *pdata)
421 {
422 	const struct lpss_device_desc *dev_desc = pdata->dev_desc;
423 	const char *devname = dev_name(&adev->dev);
424 	struct clk *clk;
425 	struct lpss_clk_data *clk_data;
426 	const char *parent, *clk_name;
427 	void __iomem *prv_base;
428 
429 	if (!lpss_clk_dev)
430 		lpt_register_clock_device();
431 
432 	if (IS_ERR(lpss_clk_dev))
433 		return PTR_ERR(lpss_clk_dev);
434 
435 	clk_data = platform_get_drvdata(lpss_clk_dev);
436 	if (!clk_data)
437 		return -ENODEV;
438 	clk = clk_data->clk;
439 
440 	if (!pdata->mmio_base
441 	    || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
442 		return -ENODATA;
443 
444 	parent = clk_data->name;
445 	prv_base = pdata->mmio_base + dev_desc->prv_offset;
446 
447 	if (pdata->fixed_clk_rate) {
448 		clk = clk_register_fixed_rate(NULL, devname, parent, 0,
449 					      pdata->fixed_clk_rate);
450 		goto out;
451 	}
452 
453 	if (dev_desc->flags & LPSS_CLK_GATE) {
454 		clk = clk_register_gate(NULL, devname, parent, 0,
455 					prv_base, 0, 0, NULL);
456 		parent = devname;
457 	}
458 
459 	if (dev_desc->flags & LPSS_CLK_DIVIDER) {
460 		/* Prevent division by zero */
461 		if (!readl(prv_base))
462 			writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
463 
464 		clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
465 		if (!clk_name)
466 			return -ENOMEM;
467 		clk = clk_register_fractional_divider(NULL, clk_name, parent,
468 						      0, prv_base, 1, 15, 16, 15,
469 						      CLK_FRAC_DIVIDER_POWER_OF_TWO_PS,
470 						      NULL);
471 		parent = clk_name;
472 
473 		clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
474 		if (!clk_name) {
475 			kfree(parent);
476 			return -ENOMEM;
477 		}
478 		clk = clk_register_gate(NULL, clk_name, parent,
479 					CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
480 					prv_base, 31, 0, NULL);
481 		kfree(parent);
482 		kfree(clk_name);
483 	}
484 out:
485 	if (IS_ERR(clk))
486 		return PTR_ERR(clk);
487 
488 	pdata->clk = clk;
489 	clk_register_clkdev(clk, dev_desc->clk_con_id, devname);
490 	return 0;
491 }
492 
493 struct lpss_device_links {
494 	const char *supplier_hid;
495 	const char *supplier_uid;
496 	const char *consumer_hid;
497 	const char *consumer_uid;
498 	u32 flags;
499 	const struct dmi_system_id *dep_missing_ids;
500 };
501 
502 /* Please keep this list sorted alphabetically by vendor and model */
503 static const struct dmi_system_id i2c1_dep_missing_dmi_ids[] = {
504 	{
505 		.matches = {
506 			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
507 			DMI_MATCH(DMI_PRODUCT_NAME, "T200TA"),
508 		},
509 	},
510 	{}
511 };
512 
513 /*
514  * The _DEP method is used to identify dependencies but instead of creating
515  * device links for every handle in _DEP, only links in the following list are
516  * created. That is necessary because, in the general case, _DEP can refer to
517  * devices that might not have drivers, or that are on different buses, or where
518  * the supplier is not enumerated until after the consumer is probed.
519  */
520 static const struct lpss_device_links lpss_device_links[] = {
521 	/* CHT External sdcard slot controller depends on PMIC I2C ctrl */
522 	{"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME},
523 	/* CHT iGPU depends on PMIC I2C controller */
524 	{"808622C1", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
525 	/* BYT iGPU depends on the Embedded Controller I2C controller (UID 1) */
526 	{"80860F41", "1", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME,
527 	 i2c1_dep_missing_dmi_ids},
528 	/* BYT CR iGPU depends on PMIC I2C controller (UID 5 on CR) */
529 	{"80860F41", "5", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
530 	/* BYT iGPU depends on PMIC I2C controller (UID 7 on non CR) */
531 	{"80860F41", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
532 };
533 
534 static bool acpi_lpss_is_supplier(struct acpi_device *adev,
535 				  const struct lpss_device_links *link)
536 {
537 	return acpi_dev_hid_uid_match(adev, link->supplier_hid, link->supplier_uid);
538 }
539 
540 static bool acpi_lpss_is_consumer(struct acpi_device *adev,
541 				  const struct lpss_device_links *link)
542 {
543 	return acpi_dev_hid_uid_match(adev, link->consumer_hid, link->consumer_uid);
544 }
545 
546 struct hid_uid {
547 	const char *hid;
548 	const char *uid;
549 };
550 
551 static int match_hid_uid(struct device *dev, const void *data)
552 {
553 	struct acpi_device *adev = ACPI_COMPANION(dev);
554 	const struct hid_uid *id = data;
555 
556 	if (!adev)
557 		return 0;
558 
559 	return acpi_dev_hid_uid_match(adev, id->hid, id->uid);
560 }
561 
562 static struct device *acpi_lpss_find_device(const char *hid, const char *uid)
563 {
564 	struct device *dev;
565 
566 	struct hid_uid data = {
567 		.hid = hid,
568 		.uid = uid,
569 	};
570 
571 	dev = bus_find_device(&platform_bus_type, NULL, &data, match_hid_uid);
572 	if (dev)
573 		return dev;
574 
575 	return bus_find_device(&pci_bus_type, NULL, &data, match_hid_uid);
576 }
577 
578 static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle)
579 {
580 	struct acpi_handle_list dep_devices;
581 	acpi_status status;
582 	int i;
583 
584 	if (!acpi_has_method(adev->handle, "_DEP"))
585 		return false;
586 
587 	status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
588 					 &dep_devices);
589 	if (ACPI_FAILURE(status)) {
590 		dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
591 		return false;
592 	}
593 
594 	for (i = 0; i < dep_devices.count; i++) {
595 		if (dep_devices.handles[i] == handle)
596 			return true;
597 	}
598 
599 	return false;
600 }
601 
602 static void acpi_lpss_link_consumer(struct device *dev1,
603 				    const struct lpss_device_links *link)
604 {
605 	struct device *dev2;
606 
607 	dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid);
608 	if (!dev2)
609 		return;
610 
611 	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
612 	    || acpi_lpss_dep(ACPI_COMPANION(dev2), ACPI_HANDLE(dev1)))
613 		device_link_add(dev2, dev1, link->flags);
614 
615 	put_device(dev2);
616 }
617 
618 static void acpi_lpss_link_supplier(struct device *dev1,
619 				    const struct lpss_device_links *link)
620 {
621 	struct device *dev2;
622 
623 	dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid);
624 	if (!dev2)
625 		return;
626 
627 	if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
628 	    || acpi_lpss_dep(ACPI_COMPANION(dev1), ACPI_HANDLE(dev2)))
629 		device_link_add(dev1, dev2, link->flags);
630 
631 	put_device(dev2);
632 }
633 
634 static void acpi_lpss_create_device_links(struct acpi_device *adev,
635 					  struct platform_device *pdev)
636 {
637 	int i;
638 
639 	for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) {
640 		const struct lpss_device_links *link = &lpss_device_links[i];
641 
642 		if (acpi_lpss_is_supplier(adev, link))
643 			acpi_lpss_link_consumer(&pdev->dev, link);
644 
645 		if (acpi_lpss_is_consumer(adev, link))
646 			acpi_lpss_link_supplier(&pdev->dev, link);
647 	}
648 }
649 
650 static int acpi_lpss_create_device(struct acpi_device *adev,
651 				   const struct acpi_device_id *id)
652 {
653 	const struct lpss_device_desc *dev_desc;
654 	struct lpss_private_data *pdata;
655 	struct resource_entry *rentry;
656 	struct list_head resource_list;
657 	struct platform_device *pdev;
658 	int ret;
659 
660 	dev_desc = (const struct lpss_device_desc *)id->driver_data;
661 	if (!dev_desc) {
662 		pdev = acpi_create_platform_device(adev, NULL);
663 		return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
664 	}
665 	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
666 	if (!pdata)
667 		return -ENOMEM;
668 
669 	INIT_LIST_HEAD(&resource_list);
670 	ret = acpi_dev_get_memory_resources(adev, &resource_list);
671 	if (ret < 0)
672 		goto err_out;
673 
674 	rentry = list_first_entry_or_null(&resource_list, struct resource_entry, node);
675 	if (rentry) {
676 		if (dev_desc->prv_size_override)
677 			pdata->mmio_size = dev_desc->prv_size_override;
678 		else
679 			pdata->mmio_size = resource_size(rentry->res);
680 		pdata->mmio_base = ioremap(rentry->res->start, pdata->mmio_size);
681 	}
682 
683 	acpi_dev_free_resource_list(&resource_list);
684 
685 	if (!pdata->mmio_base) {
686 		/* Avoid acpi_bus_attach() instantiating a pdev for this dev. */
687 		adev->pnp.type.platform_id = 0;
688 		goto out_free;
689 	}
690 
691 	pdata->adev = adev;
692 	pdata->dev_desc = dev_desc;
693 
694 	if (dev_desc->setup)
695 		dev_desc->setup(pdata);
696 
697 	if (dev_desc->flags & LPSS_CLK) {
698 		ret = register_device_clock(adev, pdata);
699 		if (ret)
700 			goto out_free;
701 	}
702 
703 	/*
704 	 * This works around a known issue in ACPI tables where LPSS devices
705 	 * have _PS0 and _PS3 without _PSC (and no power resources), so
706 	 * acpi_bus_init_power() will assume that the BIOS has put them into D0.
707 	 */
708 	acpi_device_fix_up_power(adev);
709 
710 	adev->driver_data = pdata;
711 	pdev = acpi_create_platform_device(adev, dev_desc->properties);
712 	if (IS_ERR_OR_NULL(pdev)) {
713 		adev->driver_data = NULL;
714 		ret = PTR_ERR(pdev);
715 		goto err_out;
716 	}
717 
718 	acpi_lpss_create_device_links(adev, pdev);
719 	return 1;
720 
721 out_free:
722 	/* Skip the device, but continue the namespace scan */
723 	ret = 0;
724 err_out:
725 	kfree(pdata);
726 	return ret;
727 }
728 
729 static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
730 {
731 	return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
732 }
733 
734 static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
735 			     unsigned int reg)
736 {
737 	writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
738 }
739 
740 static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val)
741 {
742 	struct acpi_device *adev = ACPI_COMPANION(dev);
743 	struct lpss_private_data *pdata;
744 	unsigned long flags;
745 	int ret;
746 
747 	if (WARN_ON(!adev))
748 		return -ENODEV;
749 
750 	spin_lock_irqsave(&dev->power.lock, flags);
751 	if (pm_runtime_suspended(dev)) {
752 		ret = -EAGAIN;
753 		goto out;
754 	}
755 	pdata = acpi_driver_data(adev);
756 	if (WARN_ON(!pdata || !pdata->mmio_base)) {
757 		ret = -ENODEV;
758 		goto out;
759 	}
760 	*val = __lpss_reg_read(pdata, reg);
761 	ret = 0;
762 
763  out:
764 	spin_unlock_irqrestore(&dev->power.lock, flags);
765 	return ret;
766 }
767 
768 static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr,
769 			     char *buf)
770 {
771 	u32 ltr_value = 0;
772 	unsigned int reg;
773 	int ret;
774 
775 	reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR;
776 	ret = lpss_reg_read(dev, reg, &ltr_value);
777 	if (ret)
778 		return ret;
779 
780 	return sysfs_emit(buf, "%08x\n", ltr_value);
781 }
782 
783 static ssize_t lpss_ltr_mode_show(struct device *dev,
784 				  struct device_attribute *attr, char *buf)
785 {
786 	u32 ltr_mode = 0;
787 	char *outstr;
788 	int ret;
789 
790 	ret = lpss_reg_read(dev, LPSS_GENERAL, &ltr_mode);
791 	if (ret)
792 		return ret;
793 
794 	outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto";
795 	return sprintf(buf, "%s\n", outstr);
796 }
797 
798 static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL);
799 static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL);
800 static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL);
801 
802 static struct attribute *lpss_attrs[] = {
803 	&dev_attr_auto_ltr.attr,
804 	&dev_attr_sw_ltr.attr,
805 	&dev_attr_ltr_mode.attr,
806 	NULL,
807 };
808 
809 static const struct attribute_group lpss_attr_group = {
810 	.attrs = lpss_attrs,
811 	.name = "lpss_ltr",
812 };
813 
814 static void acpi_lpss_set_ltr(struct device *dev, s32 val)
815 {
816 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
817 	u32 ltr_mode, ltr_val;
818 
819 	ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
820 	if (val < 0) {
821 		if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
822 			ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
823 			__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
824 		}
825 		return;
826 	}
827 	ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
828 	if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
829 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
830 		val = LPSS_LTR_MAX_VAL;
831 	} else if (val > LPSS_LTR_MAX_VAL) {
832 		ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
833 		val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
834 	} else {
835 		ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
836 	}
837 	ltr_val |= val;
838 	__lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
839 	if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
840 		ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
841 		__lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
842 	}
843 }
844 
845 #ifdef CONFIG_PM
846 /**
847  * acpi_lpss_save_ctx() - Save the private registers of LPSS device
848  * @dev: LPSS device
849  * @pdata: pointer to the private data of the LPSS device
850  *
851  * Most LPSS devices have private registers which may loose their context when
852  * the device is powered down. acpi_lpss_save_ctx() saves those registers into
853  * prv_reg_ctx array.
854  */
855 static void acpi_lpss_save_ctx(struct device *dev,
856 			       struct lpss_private_data *pdata)
857 {
858 	unsigned int i;
859 
860 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
861 		unsigned long offset = i * sizeof(u32);
862 
863 		pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
864 		dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
865 			pdata->prv_reg_ctx[i], offset);
866 	}
867 }
868 
869 /**
870  * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
871  * @dev: LPSS device
872  * @pdata: pointer to the private data of the LPSS device
873  *
874  * Restores the registers that were previously stored with acpi_lpss_save_ctx().
875  */
876 static void acpi_lpss_restore_ctx(struct device *dev,
877 				  struct lpss_private_data *pdata)
878 {
879 	unsigned int i;
880 
881 	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
882 		unsigned long offset = i * sizeof(u32);
883 
884 		__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
885 		dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
886 			pdata->prv_reg_ctx[i], offset);
887 	}
888 }
889 
890 static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
891 {
892 	/*
893 	 * The following delay is needed or the subsequent write operations may
894 	 * fail. The LPSS devices are actually PCI devices and the PCI spec
895 	 * expects 10ms delay before the device can be accessed after D3 to D0
896 	 * transition. However some platforms like BSW does not need this delay.
897 	 */
898 	unsigned int delay = 10;	/* default 10ms delay */
899 
900 	if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)
901 		delay = 0;
902 
903 	msleep(delay);
904 }
905 
906 static int acpi_lpss_activate(struct device *dev)
907 {
908 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
909 	int ret;
910 
911 	ret = acpi_dev_resume(dev);
912 	if (ret)
913 		return ret;
914 
915 	acpi_lpss_d3_to_d0_delay(pdata);
916 
917 	/*
918 	 * This is called only on ->probe() stage where a device is either in
919 	 * known state defined by BIOS or most likely powered off. Due to this
920 	 * we have to deassert reset line to be sure that ->probe() will
921 	 * recognize the device.
922 	 */
923 	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
924 		lpss_deassert_reset(pdata);
925 
926 #ifdef CONFIG_PM
927 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX_ONCE)
928 		acpi_lpss_save_ctx(dev, pdata);
929 #endif
930 
931 	return 0;
932 }
933 
934 static void acpi_lpss_dismiss(struct device *dev)
935 {
936 	acpi_dev_suspend(dev, false);
937 }
938 
939 /* IOSF SB for LPSS island */
940 #define LPSS_IOSF_UNIT_LPIOEP		0xA0
941 #define LPSS_IOSF_UNIT_LPIO1		0xAB
942 #define LPSS_IOSF_UNIT_LPIO2		0xAC
943 
944 #define LPSS_IOSF_PMCSR			0x84
945 #define LPSS_PMCSR_D0			0
946 #define LPSS_PMCSR_D3hot		3
947 #define LPSS_PMCSR_Dx_MASK		GENMASK(1, 0)
948 
949 #define LPSS_IOSF_GPIODEF0		0x154
950 #define LPSS_GPIODEF0_DMA1_D3		BIT(2)
951 #define LPSS_GPIODEF0_DMA2_D3		BIT(3)
952 #define LPSS_GPIODEF0_DMA_D3_MASK	GENMASK(3, 2)
953 #define LPSS_GPIODEF0_DMA_LLP		BIT(13)
954 
955 static DEFINE_MUTEX(lpss_iosf_mutex);
956 static bool lpss_iosf_d3_entered = true;
957 
958 static void lpss_iosf_enter_d3_state(void)
959 {
960 	u32 value1 = 0;
961 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
962 	u32 value2 = LPSS_PMCSR_D3hot;
963 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
964 	/*
965 	 * PMC provides an information about actual status of the LPSS devices.
966 	 * Here we read the values related to LPSS power island, i.e. LPSS
967 	 * devices, excluding both LPSS DMA controllers, along with SCC domain.
968 	 */
969 	u32 func_dis, d3_sts_0, pmc_status;
970 	int ret;
971 
972 	ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);
973 	if (ret)
974 		return;
975 
976 	mutex_lock(&lpss_iosf_mutex);
977 
978 	ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);
979 	if (ret)
980 		goto exit;
981 
982 	/*
983 	 * Get the status of entire LPSS power island per device basis.
984 	 * Shutdown both LPSS DMA controllers if and only if all other devices
985 	 * are already in D3hot.
986 	 */
987 	pmc_status = (~(d3_sts_0 | func_dis)) & pmc_atom_d3_mask;
988 	if (pmc_status)
989 		goto exit;
990 
991 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
992 			LPSS_IOSF_PMCSR, value2, mask2);
993 
994 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
995 			LPSS_IOSF_PMCSR, value2, mask2);
996 
997 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
998 			LPSS_IOSF_GPIODEF0, value1, mask1);
999 
1000 	lpss_iosf_d3_entered = true;
1001 
1002 exit:
1003 	mutex_unlock(&lpss_iosf_mutex);
1004 }
1005 
1006 static void lpss_iosf_exit_d3_state(void)
1007 {
1008 	u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 |
1009 		     LPSS_GPIODEF0_DMA_LLP;
1010 	u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
1011 	u32 value2 = LPSS_PMCSR_D0;
1012 	u32 mask2 = LPSS_PMCSR_Dx_MASK;
1013 
1014 	mutex_lock(&lpss_iosf_mutex);
1015 
1016 	if (!lpss_iosf_d3_entered)
1017 		goto exit;
1018 
1019 	lpss_iosf_d3_entered = false;
1020 
1021 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
1022 			LPSS_IOSF_GPIODEF0, value1, mask1);
1023 
1024 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
1025 			LPSS_IOSF_PMCSR, value2, mask2);
1026 
1027 	iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
1028 			LPSS_IOSF_PMCSR, value2, mask2);
1029 
1030 exit:
1031 	mutex_unlock(&lpss_iosf_mutex);
1032 }
1033 
1034 static int acpi_lpss_suspend(struct device *dev, bool wakeup)
1035 {
1036 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1037 	int ret;
1038 
1039 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
1040 		acpi_lpss_save_ctx(dev, pdata);
1041 
1042 	ret = acpi_dev_suspend(dev, wakeup);
1043 
1044 	/*
1045 	 * This call must be last in the sequence, otherwise PMC will return
1046 	 * wrong status for devices being about to be powered off. See
1047 	 * lpss_iosf_enter_d3_state() for further information.
1048 	 */
1049 	if (acpi_target_system_state() == ACPI_STATE_S0 &&
1050 	    lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1051 		lpss_iosf_enter_d3_state();
1052 
1053 	return ret;
1054 }
1055 
1056 static int acpi_lpss_resume(struct device *dev)
1057 {
1058 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1059 	int ret;
1060 
1061 	/*
1062 	 * This call is kept first to be in symmetry with
1063 	 * acpi_lpss_runtime_suspend() one.
1064 	 */
1065 	if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
1066 		lpss_iosf_exit_d3_state();
1067 
1068 	ret = acpi_dev_resume(dev);
1069 	if (ret)
1070 		return ret;
1071 
1072 	acpi_lpss_d3_to_d0_delay(pdata);
1073 
1074 	if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
1075 		acpi_lpss_restore_ctx(dev, pdata);
1076 
1077 	return 0;
1078 }
1079 
1080 #ifdef CONFIG_PM_SLEEP
1081 static int acpi_lpss_do_suspend_late(struct device *dev)
1082 {
1083 	int ret;
1084 
1085 	if (dev_pm_skip_suspend(dev))
1086 		return 0;
1087 
1088 	ret = pm_generic_suspend_late(dev);
1089 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1090 }
1091 
1092 static int acpi_lpss_suspend_late(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 	return acpi_lpss_do_suspend_late(dev);
1100 }
1101 
1102 static int acpi_lpss_suspend_noirq(struct device *dev)
1103 {
1104 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1105 	int ret;
1106 
1107 	if (pdata->dev_desc->resume_from_noirq) {
1108 		/*
1109 		 * The driver's ->suspend_late callback will be invoked by
1110 		 * acpi_lpss_do_suspend_late(), with the assumption that the
1111 		 * driver really wanted to run that code in ->suspend_noirq, but
1112 		 * it could not run after acpi_dev_suspend() and the driver
1113 		 * expected the latter to be called in the "late" phase.
1114 		 */
1115 		ret = acpi_lpss_do_suspend_late(dev);
1116 		if (ret)
1117 			return ret;
1118 	}
1119 
1120 	return acpi_subsys_suspend_noirq(dev);
1121 }
1122 
1123 static int acpi_lpss_do_resume_early(struct device *dev)
1124 {
1125 	int ret = acpi_lpss_resume(dev);
1126 
1127 	return ret ? ret : pm_generic_resume_early(dev);
1128 }
1129 
1130 static int acpi_lpss_resume_early(struct device *dev)
1131 {
1132 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1133 
1134 	if (pdata->dev_desc->resume_from_noirq)
1135 		return 0;
1136 
1137 	if (dev_pm_skip_resume(dev))
1138 		return 0;
1139 
1140 	return acpi_lpss_do_resume_early(dev);
1141 }
1142 
1143 static int acpi_lpss_resume_noirq(struct device *dev)
1144 {
1145 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1146 	int ret;
1147 
1148 	/* Follow acpi_subsys_resume_noirq(). */
1149 	if (dev_pm_skip_resume(dev))
1150 		return 0;
1151 
1152 	ret = pm_generic_resume_noirq(dev);
1153 	if (ret)
1154 		return ret;
1155 
1156 	if (!pdata->dev_desc->resume_from_noirq)
1157 		return 0;
1158 
1159 	/*
1160 	 * The driver's ->resume_early callback will be invoked by
1161 	 * acpi_lpss_do_resume_early(), with the assumption that the driver
1162 	 * really wanted to run that code in ->resume_noirq, but it could not
1163 	 * run before acpi_dev_resume() and the driver expected the latter to be
1164 	 * called in the "early" phase.
1165 	 */
1166 	return acpi_lpss_do_resume_early(dev);
1167 }
1168 
1169 static int acpi_lpss_do_restore_early(struct device *dev)
1170 {
1171 	int ret = acpi_lpss_resume(dev);
1172 
1173 	return ret ? ret : pm_generic_restore_early(dev);
1174 }
1175 
1176 static int acpi_lpss_restore_early(struct device *dev)
1177 {
1178 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1179 
1180 	if (pdata->dev_desc->resume_from_noirq)
1181 		return 0;
1182 
1183 	return acpi_lpss_do_restore_early(dev);
1184 }
1185 
1186 static int acpi_lpss_restore_noirq(struct device *dev)
1187 {
1188 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1189 	int ret;
1190 
1191 	ret = pm_generic_restore_noirq(dev);
1192 	if (ret)
1193 		return ret;
1194 
1195 	if (!pdata->dev_desc->resume_from_noirq)
1196 		return 0;
1197 
1198 	/* This is analogous to what happens in acpi_lpss_resume_noirq(). */
1199 	return acpi_lpss_do_restore_early(dev);
1200 }
1201 
1202 static int acpi_lpss_do_poweroff_late(struct device *dev)
1203 {
1204 	int ret = pm_generic_poweroff_late(dev);
1205 
1206 	return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
1207 }
1208 
1209 static int acpi_lpss_poweroff_late(struct device *dev)
1210 {
1211 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1212 
1213 	if (dev_pm_skip_suspend(dev))
1214 		return 0;
1215 
1216 	if (pdata->dev_desc->resume_from_noirq)
1217 		return 0;
1218 
1219 	return acpi_lpss_do_poweroff_late(dev);
1220 }
1221 
1222 static int acpi_lpss_poweroff_noirq(struct device *dev)
1223 {
1224 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1225 
1226 	if (dev_pm_skip_suspend(dev))
1227 		return 0;
1228 
1229 	if (pdata->dev_desc->resume_from_noirq) {
1230 		/* This is analogous to the acpi_lpss_suspend_noirq() case. */
1231 		int ret = acpi_lpss_do_poweroff_late(dev);
1232 
1233 		if (ret)
1234 			return ret;
1235 	}
1236 
1237 	return pm_generic_poweroff_noirq(dev);
1238 }
1239 #endif /* CONFIG_PM_SLEEP */
1240 
1241 static int acpi_lpss_runtime_suspend(struct device *dev)
1242 {
1243 	int ret = pm_generic_runtime_suspend(dev);
1244 
1245 	return ret ? ret : acpi_lpss_suspend(dev, true);
1246 }
1247 
1248 static int acpi_lpss_runtime_resume(struct device *dev)
1249 {
1250 	int ret = acpi_lpss_resume(dev);
1251 
1252 	return ret ? ret : pm_generic_runtime_resume(dev);
1253 }
1254 #endif /* CONFIG_PM */
1255 
1256 static struct dev_pm_domain acpi_lpss_pm_domain = {
1257 #ifdef CONFIG_PM
1258 	.activate = acpi_lpss_activate,
1259 	.dismiss = acpi_lpss_dismiss,
1260 #endif
1261 	.ops = {
1262 #ifdef CONFIG_PM
1263 #ifdef CONFIG_PM_SLEEP
1264 		.prepare = acpi_subsys_prepare,
1265 		.complete = acpi_subsys_complete,
1266 		.suspend = acpi_subsys_suspend,
1267 		.suspend_late = acpi_lpss_suspend_late,
1268 		.suspend_noirq = acpi_lpss_suspend_noirq,
1269 		.resume_noirq = acpi_lpss_resume_noirq,
1270 		.resume_early = acpi_lpss_resume_early,
1271 		.freeze = acpi_subsys_freeze,
1272 		.poweroff = acpi_subsys_poweroff,
1273 		.poweroff_late = acpi_lpss_poweroff_late,
1274 		.poweroff_noirq = acpi_lpss_poweroff_noirq,
1275 		.restore_noirq = acpi_lpss_restore_noirq,
1276 		.restore_early = acpi_lpss_restore_early,
1277 #endif
1278 		.runtime_suspend = acpi_lpss_runtime_suspend,
1279 		.runtime_resume = acpi_lpss_runtime_resume,
1280 #endif
1281 	},
1282 };
1283 
1284 static int acpi_lpss_platform_notify(struct notifier_block *nb,
1285 				     unsigned long action, void *data)
1286 {
1287 	struct platform_device *pdev = to_platform_device(data);
1288 	struct lpss_private_data *pdata;
1289 	struct acpi_device *adev;
1290 	const struct acpi_device_id *id;
1291 
1292 	id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev);
1293 	if (!id || !id->driver_data)
1294 		return 0;
1295 
1296 	adev = ACPI_COMPANION(&pdev->dev);
1297 	if (!adev)
1298 		return 0;
1299 
1300 	pdata = acpi_driver_data(adev);
1301 	if (!pdata)
1302 		return 0;
1303 
1304 	if (pdata->mmio_base &&
1305 	    pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
1306 		dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
1307 		return 0;
1308 	}
1309 
1310 	switch (action) {
1311 	case BUS_NOTIFY_BIND_DRIVER:
1312 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1313 		break;
1314 	case BUS_NOTIFY_DRIVER_NOT_BOUND:
1315 	case BUS_NOTIFY_UNBOUND_DRIVER:
1316 		dev_pm_domain_set(&pdev->dev, NULL);
1317 		break;
1318 	case BUS_NOTIFY_ADD_DEVICE:
1319 		dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
1320 		if (pdata->dev_desc->flags & LPSS_LTR)
1321 			return sysfs_create_group(&pdev->dev.kobj,
1322 						  &lpss_attr_group);
1323 		break;
1324 	case BUS_NOTIFY_DEL_DEVICE:
1325 		if (pdata->dev_desc->flags & LPSS_LTR)
1326 			sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
1327 		dev_pm_domain_set(&pdev->dev, NULL);
1328 		break;
1329 	default:
1330 		break;
1331 	}
1332 
1333 	return 0;
1334 }
1335 
1336 static struct notifier_block acpi_lpss_nb = {
1337 	.notifier_call = acpi_lpss_platform_notify,
1338 };
1339 
1340 static void acpi_lpss_bind(struct device *dev)
1341 {
1342 	struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
1343 
1344 	if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
1345 		return;
1346 
1347 	if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
1348 		dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
1349 	else
1350 		dev_err(dev, "MMIO size insufficient to access LTR\n");
1351 }
1352 
1353 static void acpi_lpss_unbind(struct device *dev)
1354 {
1355 	dev->power.set_latency_tolerance = NULL;
1356 }
1357 
1358 static struct acpi_scan_handler lpss_handler = {
1359 	.ids = acpi_lpss_device_ids,
1360 	.attach = acpi_lpss_create_device,
1361 	.bind = acpi_lpss_bind,
1362 	.unbind = acpi_lpss_unbind,
1363 };
1364 
1365 void __init acpi_lpss_init(void)
1366 {
1367 	const struct x86_cpu_id *id;
1368 	int ret;
1369 
1370 	ret = lpss_atom_clk_init();
1371 	if (ret)
1372 		return;
1373 
1374 	id = x86_match_cpu(lpss_cpu_ids);
1375 	if (id)
1376 		lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;
1377 
1378 	bus_register_notifier(&platform_bus_type, &acpi_lpss_nb);
1379 	acpi_scan_add_handler(&lpss_handler);
1380 }
1381 
1382 #else
1383 
1384 static struct acpi_scan_handler lpss_handler = {
1385 	.ids = acpi_lpss_device_ids,
1386 };
1387 
1388 void __init acpi_lpss_init(void)
1389 {
1390 	acpi_scan_add_handler(&lpss_handler);
1391 }
1392 
1393 #endif /* CONFIG_X86_INTEL_LPSS */
1394