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b2441318 1# SPDX-License-Identifier: GPL-2.0
1da177e4
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2#
3# ACPI Configuration
4#
5
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6config ARCH_SUPPORTS_ACPI
7 bool
8
3f2c48c9 9menuconfig ACPI
355ee5eb 10 bool "ACPI (Advanced Configuration and Power Interface) Support"
2c870e61 11 depends on ARCH_SUPPORTS_ACPI
243b66e7 12 select PNP
2e61069b 13 select NLS
2c870e61 14 default y if X86
1c48aa36 15 help
1da177e4 16 Advanced Configuration and Power Interface (ACPI) support for
1c48aa36 17 Linux requires an ACPI-compliant platform (hardware/firmware),
1da177e4
LT
18 and assumes the presence of OS-directed configuration and power
19 management (OSPM) software. This option will enlarge your
20 kernel by about 70K.
21
22 Linux ACPI provides a robust functional replacement for several
23 legacy configuration and power management interfaces, including
24 the Plug-and-Play BIOS specification (PnP BIOS), the
25 MultiProcessor Specification (MPS), and the Advanced Power
26 Management (APM) specification. If both ACPI and APM support
1c48aa36 27 are configured, ACPI is used.
1da177e4 28
1c48aa36 29 The project home page for the Linux ACPI subsystem is here:
aaf3d29f 30 <https://01.org/linux-acpi>
1da177e4
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31
32 Linux support for ACPI is based on Intel Corporation's ACPI
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33 Component Architecture (ACPI CA). For more information on the
34 ACPI CA, see:
35 <http://acpica.org/>
1da177e4 36
c7f5220d
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37 ACPI is an open industry specification originally co-developed by
38 Hewlett-Packard, Intel, Microsoft, Phoenix, and Toshiba. Currently,
39 it is developed by the ACPI Specification Working Group (ASWG) under
40 the UEFI Forum and any UEFI member can join the ASWG and contribute
41 to the ACPI specification.
1c48aa36 42 The specification is available at:
1da177e4 43 <http://www.acpi.info>
c7f5220d 44 <http://www.uefi.org/acpi/specs>
1da177e4 45
3e11c3ce
LB
46if ACPI
47
8a1664be
GG
48config ACPI_LEGACY_TABLES_LOOKUP
49 bool
50
46ba51ea
HG
51config ARCH_MIGHT_HAVE_ACPI_PDC
52 bool
53
d8f4f161
LP
54config ACPI_GENERIC_GSI
55 bool
56
6e0a0ea1
GG
57config ACPI_SYSTEM_POWER_STATES_SUPPORT
58 bool
59
d0562674
SS
60config ACPI_CCA_REQUIRED
61 bool
62
4d946f79 63config ACPI_DEBUGGER
8cfb0cdf 64 bool "AML debugger interface"
4d946f79
LZ
65 select ACPI_DEBUG
66 help
836d0830
LZ
67 Enable in-kernel debugging of AML facilities: statistics,
68 internal object dump, single step control method execution.
4d946f79
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69 This is still under development, currently enabling this only
70 results in the compilation of the ACPICA debugger files.
71
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72if ACPI_DEBUGGER
73
74config ACPI_DEBUGGER_USER
75 tristate "Userspace debugger accessiblity"
76 depends on DEBUG_FS
77 help
78 Export /sys/kernel/debug/acpi/acpidbg for userspace utilities
79 to access the debugger functionalities.
80
81endif
82
ad1696f6 83config ACPI_SPCR_TABLE
0231d000
PB
84 bool "ACPI Serial Port Console Redirection Support"
85 default y if X86
86 help
87 Enable support for Serial Port Console Redirection (SPCR) Table.
88 This table provides information about the configuration of the
89 earlycon console.
ad1696f6 90
eeb2d80d
SP
91config ACPI_LPIT
92 bool
93 depends on X86_64
94 default y
95
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96config ACPI_SLEEP
97 bool
5d1e072b 98 depends on SUSPEND || HIBERNATION
6e0a0ea1 99 depends on ACPI_SYSTEM_POWER_STATES_SUPPORT
673d5b43
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100 default y
101
e2a7c3d7
LT
102config ACPI_PROCFS_POWER
103 bool "Deprecated power /proc/acpi directories"
bbf55ae1 104 depends on X86 && PROC_FS
e2a7c3d7
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105 help
106 For backwards compatibility, this option allows
107 deprecated power /proc/acpi/ directories to exist, even when
108 they have been replaced by functions in /sys.
109 The deprecated directories (and their replacements) include:
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RD
110 /proc/acpi/battery/* (/sys/class/power_supply/*) and
111 /proc/acpi/ac_adapter/* (sys/class/power_supply/*).
e2a7c3d7 112 This option has no effect on /proc/acpi/ directories
7e46b32b 113 and functions which do not yet exist in /sys.
e2a7c3d7 114 This option, together with the proc directories, will be
3afcb96f 115 deleted in the future.
e2a7c3d7 116
7e46b32b 117 Say N to delete power /proc/acpi/ directories that have moved to /sys.
e2a7c3d7 118
18d78b64 119config ACPI_REV_OVERRIDE_POSSIBLE
9165dabb 120 bool "Allow supported ACPI revision to be overridden"
18d78b64
RW
121 depends on X86
122 default y
123 help
124 The platform firmware on some systems expects Linux to return "5" as
125 the supported ACPI revision which makes it expose system configuration
126 information in a special way.
127
128 For example, based on what ACPI exports as the supported revision,
129 Dell XPS 13 (2015) configures its audio device to either work in HDA
130 mode or in I2S mode, where the former is supposed to be used on Linux
131 until the latter is fully supported (in the kernel as well as in user
132 space).
133
134 This option enables a DMI-based quirk for the above Dell machine (so
135 that HDA audio is exposed by the platform firmware to the kernel) and
136 makes it possible to force the kernel to return "5" as the supported
137 ACPI revision via the "acpi_rev_override" command line switch.
138
1195a098
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139config ACPI_EC_DEBUGFS
140 tristate "EC read/write access through /sys/kernel/debug/ec"
1195a098
TR
141 help
142 Say N to disable Embedded Controller /sys/kernel/debug interface
143
500de3dd
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144 Be aware that using this interface can confuse your Embedded
145 Controller in a way that a normal reboot is not enough. You then
25cb1bfd 146 have to power off your system, and remove the laptop battery for
500de3dd 147 some seconds.
1195a098
TR
148 An Embedded Controller typically is available on laptops and reads
149 sensor values like battery state and temperature.
500de3dd
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150 The kernel accesses the EC through ACPI parsed code provided by BIOS
151 tables. This option allows to access the EC directly without ACPI
152 code being involved.
1195a098
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153 Thus this option is a debug option that helps to write ACPI drivers
154 and can be used to identify ACPI code or EC firmware bugs.
155
1da177e4
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156config ACPI_AC
157 tristate "AC Adapter"
5527c8be 158 depends on X86
1b3d4c3b 159 select POWER_SUPPLY
07fefe4c 160 default y
1da177e4 161 help
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162 This driver supports the AC Adapter object, which indicates
163 whether a system is on AC or not. If you have a system that can
07fefe4c 164 switch between A/C and battery, say Y.
1da177e4 165
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166 To compile this driver as a module, choose M here:
167 the module will be called ac.
168
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169config ACPI_BATTERY
170 tristate "Battery"
5527c8be 171 depends on X86
1b3d4c3b 172 select POWER_SUPPLY
07fefe4c 173 default y
1da177e4
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174 help
175 This driver adds support for battery information through
176 /proc/acpi/battery. If you have a mobile system with a battery,
177 say Y.
178
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179 To compile this driver as a module, choose M here:
180 the module will be called battery.
181
1da177e4
LT
182config ACPI_BUTTON
183 tristate "Button"
c0968f0e 184 depends on INPUT
07fefe4c 185 default y
1da177e4 186 help
1c48aa36 187 This driver handles events on the power, sleep, and lid buttons.
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188 A daemon reads events from input devices or via netlink and
189 performs user-defined actions such as shutting down the system.
190 This is necessary for software-controlled poweroff.
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191
192 To compile this driver as a module, choose M here:
193 the module will be called button.
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194
195config ACPI_VIDEO
196 tristate "Video"
9f380fc5 197 depends on X86 && BACKLIGHT_CLASS_DEVICE
03e2bf26 198 depends on INPUT
63c4ec90 199 select THERMAL
1da177e4 200 help
1c48aa36 201 This driver implements the ACPI Extensions For Display Adapters
1da177e4 202 for integrated graphics devices on motherboard, as specified in
1c48aa36
BH
203 ACPI 2.0 Specification, Appendix B. This supports basic operations
204 such as defining the video POST device, retrieving EDID information,
205 and setting up a video output.
206
207 To compile this driver as a module, choose M here:
208 the module will be called video.
1da177e4
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209
210config ACPI_FAN
211 tristate "Fan"
d8054749 212 depends on THERMAL
07fefe4c 213 default y
1da177e4 214 help
1c48aa36 215 This driver supports ACPI fan devices, allowing user-mode
1da177e4
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216 applications to perform basic fan control (on, off, status).
217
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218 To compile this driver as a module, choose M here:
219 the module will be called fan.
220
95c513ec
RW
221config ACPI_TAD
222 tristate "ACPI Time and Alarm (TAD) Device Support"
223 depends on SYSFS && PM_SLEEP
224 help
225 The ACPI Time and Alarm (TAD) device is an alternative to the Real
226 Time Clock (RTC). Its wake timers allow the system to transition from
227 the S3 (or optionally S4/S5) state to S0 state after a time period
228 elapses. In comparison with the RTC Alarm, the TAD provides a larger
229 scale of flexibility in the wake timers. The time capabilities of the
230 TAD maintain the time of day information across platform power
231 transitions, and keep track of time even when the platform is turned
232 off.
233
c8f7a62c 234config ACPI_DOCK
898b054f 235 bool "Dock"
c8f7a62c 236 help
1c48aa36
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237 This driver supports ACPI-controlled docking stations and removable
238 drive bays such as the IBM Ultrabay and the Dell Module Bay.
01b57e73 239
239708a3
AC
240config ACPI_CPU_FREQ_PSS
241 bool
242 select THERMAL
243
35ae7133
SH
244config ACPI_PROCESSOR_CSTATE
245 def_bool y
246 depends on IA64 || X86
247
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AC
248config ACPI_PROCESSOR_IDLE
249 bool
250 select CPU_IDLE
251
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252config ACPI_MCFG
253 bool
254
337aadff
AC
255config ACPI_CPPC_LIB
256 bool
257 depends on ACPI_PROCESSOR
337aadff
AC
258 select MAILBOX
259 select PCC
260 help
261 If this option is enabled, this file implements common functionality
262 to parse CPPC tables as described in the ACPI 5.1+ spec. The
263 routines implemented are meant to be used by other
264 drivers to control CPU performance using CPPC semantics.
265 If your platform does not support CPPC in firmware,
266 leave this option disabled.
267
1da177e4
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268config ACPI_PROCESSOR
269 tristate "Processor"
ad806ea6 270 depends on X86 || IA64 || ARM64
8fc85c6a 271 select ACPI_PROCESSOR_IDLE
ad806ea6 272 select ACPI_CPU_FREQ_PSS if X86 || IA64
07fefe4c 273 default y
1da177e4 274 help
239708a3
AC
275 This driver adds support for the ACPI Processor package. It is required
276 by several flavors of cpufreq performance-state, thermal, throttling and
277 idle drivers.
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BH
278
279 To compile this driver as a module, choose M here:
280 the module will be called processor.
4b88e330 281
e92b297c
ZY
282config ACPI_IPMI
283 tristate "IPMI"
50121beb 284 depends on IPMI_HANDLER
e92b297c
ZY
285 help
286 This driver enables the ACPI to access the BMC controller. And it
287 uses the IPMI request/response message to communicate with BMC
288 controller, which can be found on on the server.
289
290 To compile this driver as a module, choose M here:
291 the module will be called as acpi_ipmi.
1da177e4
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292
293config ACPI_HOTPLUG_CPU
cbfc1bae 294 bool
f756f28b 295 depends on ACPI_PROCESSOR && HOTPLUG_CPU
1da177e4 296 select ACPI_CONTAINER
cbfc1bae 297 default y
1da177e4 298
8e0af514
SL
299config ACPI_PROCESSOR_AGGREGATOR
300 tristate "Processor Aggregator"
301 depends on ACPI_PROCESSOR
d91f79eb 302 depends on X86
8e0af514
SL
303 help
304 ACPI 4.0 defines processor Aggregator, which enables OS to perform
c4c4e2a5 305 specific processor configuration and control that applies to all
8e0af514
SL
306 processors in the platform. Currently only logical processor idling
307 is defined, which is to reduce power consumption. This driver
c4c4e2a5 308 supports the new device.
8e0af514 309
1da177e4
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310config ACPI_THERMAL
311 tristate "Thermal Zone"
312 depends on ACPI_PROCESSOR
3f655ef8 313 select THERMAL
07fefe4c 314 default y
1da177e4 315 help
1c48aa36 316 This driver supports ACPI thermal zones. Most mobile and
1da177e4
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317 some desktop systems support ACPI thermal zones. It is HIGHLY
318 recommended that this option be enabled, as your processor(s)
319 may be damaged without it.
320
1c48aa36
BH
321 To compile this driver as a module, choose M here:
322 the module will be called thermal.
323
1da177e4
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324config ACPI_NUMA
325 bool "NUMA support"
326 depends on NUMA
4bac6fa7
HG
327 depends on (X86 || IA64 || ARM64)
328 default y if IA64_GENERIC || IA64_SGI_SN2 || ARM64
1da177e4 329
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RD
330config ACPI_CUSTOM_DSDT_FILE
331 string "Custom DSDT Table file to include"
332 default ""
1da177e4 333 depends on !STANDALONE
1da177e4 334 help
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335 This option supports a custom DSDT by linking it into the kernel.
336 See Documentation/acpi/dsdt-override.txt
337
c30fe7f7 338 Enter the full path name to the file which includes the AmlCode
82e4eb4e 339 or dsdt_aml_code declaration.
1da177e4 340
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RD
341 If unsure, don't enter a file name.
342
343config ACPI_CUSTOM_DSDT
344 bool
345 default ACPI_CUSTOM_DSDT_FILE != ""
346
91dda51a
AM
347config ARCH_HAS_ACPI_TABLE_UPGRADE
348 def_bool n
349
5d881327
LZ
350config ACPI_TABLE_UPGRADE
351 bool "Allow upgrading ACPI tables via initrd"
91dda51a 352 depends on BLK_DEV_INITRD && ARCH_HAS_ACPI_TABLE_UPGRADE
5d881327 353 default y
53aac44c 354 help
5d881327 355 This option provides functionality to upgrade arbitrary ACPI tables
53aac44c
TR
356 via initrd. No functional change if no ACPI tables are passed via
357 initrd, therefore it's safe to say Y.
358 See Documentation/acpi/initrd_table_override.txt for details
359
1da177e4
LT
360config ACPI_DEBUG
361 bool "Debug Statements"
1da177e4 362 help
a0d84a92
BH
363 The ACPI subsystem can produce debug output. Saying Y enables this
364 output and increases the kernel size by around 50K.
365
366 Use the acpi.debug_layer and acpi.debug_level kernel command-line
367 parameters documented in Documentation/acpi/debug.txt and
8c27ceff 368 Documentation/admin-guide/kernel-parameters.rst to control the type and
a0d84a92 369 amount of debug output.
1da177e4 370
8344b568 371config ACPI_PCI_SLOT
ab1a2e03 372 bool "PCI slot detection driver"
5c6a1177 373 depends on SYSFS && PCI
8344b568 374 help
1c48aa36
BH
375 This driver creates entries in /sys/bus/pci/slots/ for all PCI
376 slots in the system. This can help correlate PCI bus addresses,
377 i.e., segment/bus/device/function tuples, with physical slots in
378 the system. If you are unsure, say N.
379
1da177e4 380config ACPI_CONTAINER
06991c28 381 bool "Container and Module Devices"
ea6a4581 382 default (ACPI_HOTPLUG_MEMORY || ACPI_HOTPLUG_CPU)
1c48aa36
BH
383 help
384 This driver supports ACPI Container and Module devices (IDs
385 ACPI0004, PNP0A05, and PNP0A06).
45b1b196 386
1c48aa36
BH
387 This helps support hotplug of nodes, CPUs, and memory.
388
389 To compile this driver as a module, choose M here:
390 the module will be called container.
1da177e4
LT
391
392config ACPI_HOTPLUG_MEMORY
0a347644 393 bool "Memory Hotplug"
bc02af93 394 depends on MEMORY_HOTPLUG
1da177e4 395 help
1c48aa36
BH
396 This driver supports ACPI memory hotplug. The driver
397 fields notifications on ACPI memory devices (PNP0C80),
398 which represent memory ranges that may be onlined or
399 offlined during runtime.
1da177e4 400
1c48aa36
BH
401 If your hardware and firmware do not support adding or
402 removing memory devices at runtime, you need not enable
403 this driver.
1da177e4 404
1c48aa36
BH
405 To compile this driver as a module, choose M here:
406 the module will be called acpi_memhotplug.
3f86b832 407
c183619b
JL
408config ACPI_HOTPLUG_IOAPIC
409 bool
410 depends on PCI
411 depends on X86_IO_APIC
412 default y
413
3f86b832 414config ACPI_SBS
94f6c086 415 tristate "Smart Battery System"
b4150fc4 416 depends on X86
1b3d4c3b 417 select POWER_SUPPLY
3f86b832 418 help
1c48aa36 419 This driver supports the Smart Battery System, another
94f6c086 420 type of access to battery information, found on some laptops.
3f86b832 421
1c48aa36
BH
422 To compile this driver as a module, choose M here:
423 the modules will be called sbs and sbshc.
424
801eab81
HY
425config ACPI_HED
426 tristate "Hardware Error Device"
427 help
428 This driver supports the Hardware Error Device (PNP0C33),
429 which is used to report some hardware errors notified via
430 SCI, mainly the corrected errors.
431
526b4af4
TR
432config ACPI_CUSTOM_METHOD
433 tristate "Allow ACPI methods to be inserted/replaced at run time"
434 depends on DEBUG_FS
526b4af4 435 help
bd1b2a55 436 This debug facility allows ACPI AML methods to be inserted and/or
526b4af4
TR
437 replaced without rebooting the system. For details refer to:
438 Documentation/acpi/method-customizing.txt.
439
440 NOTE: This option is security sensitive, because it allows arbitrary
441 kernel memory to be written to by root (uid=0) users, allowing them
442 to bypass certain security measures (e.g. if root is not allowed to
443 load additional kernel modules after boot, this feature may be used
444 to override that restriction).
445
d1ff4b1c 446config ACPI_BGRT
2223af38 447 bool "Boottime Graphics Resource Table support"
6e7300cf 448 depends on EFI && (X86 || ARM64)
d1ff4b1c
MG
449 help
450 This driver adds support for exposing the ACPI Boottime Graphics
451 Resource Table, which allows the operating system to obtain
452 data from the firmware boot splash. It will appear under
453 /sys/firmware/acpi/bgrt/ .
454
af1ae78a
AS
455config ACPI_REDUCED_HARDWARE_ONLY
456 bool "Hardware-reduced ACPI support only" if EXPERT
457 def_bool n
af1ae78a 458 help
99a33ffc
HG
459 This config item changes the way the ACPI code is built. When this
460 option is selected, the kernel will use a specialized version of
461 ACPICA that ONLY supports the ACPI "reduced hardware" mode. The
462 resulting kernel will be smaller but it will also be restricted to
463 running in ACPI reduced hardware mode ONLY.
af1ae78a 464
99a33ffc 465 If you are unsure what to do, do not enable this option.
af1ae78a 466
bdf97013 467source "drivers/acpi/nfit/Kconfig"
62232e45 468
a643ce20 469source "drivers/acpi/apei/Kconfig"
6256ebd5 470source "drivers/acpi/dptf/Kconfig"
a643ce20 471
058dfc76
MW
472config ACPI_WATCHDOG
473 bool
474
4b3db708
CG
475config ACPI_EXTLOG
476 tristate "Extended Error Log support"
9613916b 477 depends on X86_MCE && X86_LOCAL_APIC && EDAC
7ea6c6c1 478 select UEFI_CPER
4b3db708
CG
479 help
480 Certain usages such as Predictive Failure Analysis (PFA) require
481 more information about the error than what can be described in
482 processor machine check banks. Most server processors log
483 additional information about the error in processor uncore
484 registers. Since the addresses and layout of these registers vary
485 widely from one processor to another, system software cannot
486 readily make use of them. To complicate matters further, some of
487 the additional error information cannot be constructed without
488 detailed knowledge about platform topology.
489
490 Enhanced MCA Logging allows firmware to provide additional error
491 information to system software, synchronous with MCE or CMCI. This
2dfb7d51
CG
492 driver adds support for that functionality with corresponding
493 tracepoint which carries that information to userspace.
4b3db708 494
4cf841e3
TL
495config ACPI_ADXL
496 bool
497
b1eea857
AL
498menuconfig PMIC_OPREGION
499 bool "PMIC (Power Management Integrated Circuit) operation region support"
500 help
501 Select this option to enable support for ACPI operation
502 region of the PMIC chip. The operation region can be used
503 to control power rails and sensor reading/writing on the
504 PMIC chip.
505
506if PMIC_OPREGION
507config CRC_PMIC_OPREGION
508 bool "ACPI operation region support for CrystalCove PMIC"
509 depends on INTEL_SOC_PMIC
510 help
511 This config adds ACPI operation region support for CrystalCove PMIC.
512
d8139f63
AL
513config XPOWER_PMIC_OPREGION
514 bool "ACPI operation region support for XPower AXP288 PMIC"
017ce359 515 depends on MFD_AXP20X_I2C && IOSF_MBI=y
d8139f63
AL
516 help
517 This config adds ACPI operation region support for XPower AXP288 PMIC.
518
9b928c78
BG
519config BXT_WC_PMIC_OPREGION
520 bool "ACPI operation region support for BXT WhiskeyCove PMIC"
b5238b41 521 depends on INTEL_SOC_PMIC_BXTWC
9b928c78
BG
522 help
523 This config adds ACPI operation region support for BXT WhiskeyCove PMIC.
524
ac2c4936
HG
525config CHT_WC_PMIC_OPREGION
526 bool "ACPI operation region support for CHT Whiskey Cove PMIC"
527 depends on INTEL_SOC_PMIC_CHTWC
528 help
529 This config adds ACPI operation region support for CHT Whiskey Cove PMIC.
530
31374972
TI
531config CHT_DC_TI_PMIC_OPREGION
532 bool "ACPI operation region support for Dollar Cove TI PMIC"
533 depends on INTEL_SOC_PMIC_CHTDC_TI
534 help
535 This config adds ACPI operation region support for Dollar Cove TI PMIC.
ac2c4936 536
b1eea857
AL
537endif
538
0bf54fcd
OP
539config ACPI_CONFIGFS
540 tristate "ACPI configfs support"
541 select CONFIGFS_FS
542 help
543 Select this option to enable support for ACPI configuration from
544 userspace. The configurable ACPI groups will be visible under
545 /config/acpi, assuming configfs is mounted under /config.
546
88ef16d8
TN
547if ARM64
548source "drivers/acpi/arm64/Kconfig"
0ce82232
JL
549
550config ACPI_PPTT
551 bool
88ef16d8
TN
552endif
553
e13452ac
RM
554config TPS68470_PMIC_OPREGION
555 bool "ACPI operation region support for TPS68470 PMIC"
556 depends on MFD_TPS68470
557 help
558 This config adds ACPI operation region support for TI TPS68470 PMIC.
559 TPS68470 device is an advanced power management unit that powers
560 a Compact Camera Module (CCM), generates clocks for image sensors,
561 drives a dual LED for flash and incorporates two LED drivers for
562 general purpose indicators.
563 This driver enables ACPI operation region support control voltage
564 regulators and clocks.
565
566 This option is a bool as it provides an ACPI operation
567 region, which must be available before any of the devices
568 using this, are probed.
569
1da177e4 570endif # ACPI
87e65d05
JK
571
572config X86_PM_TIMER
573 bool "Power Management Timer Support" if EXPERT
574 depends on X86 && (ACPI || JAILHOUSE_GUEST)
575 default y
576 help
577 The Power Management Timer is available on all ACPI-capable,
578 in most cases even if ACPI is unusable or blacklisted.
579
580 This timing source is not affected by power management features
581 like aggressive processor idling, throttling, frequency and/or
582 voltage scaling, unlike the commonly used Time Stamp Counter
583 (TSC) timing source.
584
585 You should nearly always say Y here because many modern
586 systems require this timer.