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* ACPI: PM: Include alternate AMDI0005 id in special behaviourSachi King2021-10-121-1/+2
| | | | | | | | | | | | | The Surface Laptop 4 AMD has used the AMD0005 to identify this controller instead of using the appropriate ACPI ID AMDI0005. The AMD0005 needs the same special casing as AMDI0005. Link: https://github.com/linux-surface/acpidumps/tree/master/surface_laptop_4_amd Link: https://gist.github.com/nakato/2a1a7df1a45fe680d7a08c583e1bf863 Signed-off-by: Sachi King <nakato@nakato.io> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Cc: 5.14+ <stable@vger.kernel.org> # 5.14+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI: PM: s2idle: Run both AMD and Microsoft methods if both are supportedMario Limonciello2021-09-021-28/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | It was reported that on "HP ENVY x360" that power LED does not come back, certain keys like brightness controls do not work, and the fan never spins up, even under load on 5.14 final. In analysis of the SSDT it's clear that the Microsoft UUID doesn't provide functional support, but rather the AMD UUID should be supporting this system. Because this is a gap in the expected logic, we checked back with internal team. The conclusion was that on Windows AMD uPEP *does* run even when Microsoft UUID present, but most OEM systems have adopted value of "0x3" for supported functions and hence nothing runs. Henceforth add support for running both Microsoft and AMD methods. This approach will also allow the same logic on Intel systems if desired at a future time as well by pulling the evaluation of `lps0_dsm_func_mask_microsoft` out of the `if` block for `acpi_s2idle_vendor_amd`. Link: https://gitlab.freedesktop.org/drm/amd/uploads/9fbcd7ec3a385cc6949c9bacf45dc41b/acpi-f.20.bin BugLink: https://gitlab.freedesktop.org/drm/amd/-/issues/1691 Reported-by: Maxwell Beck <max@ryt.one> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> [ rjw: Edits of the new comments ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI: PM: s2idle: Invert Microsoft UUID entry and exitMario Limonciello2021-08-161-2/+2
| | | | | | | | | | | | | | | | | | It was reported by a user with a Dell m15 R5 (5800H) that the keyboard backlight was turning on when entering suspend and turning off when exiting (the opposite of how it should be). The user bisected it back to commit 5dbf50997578 ("ACPI: PM: s2idle: Add support for new Microsoft UUID"). Previous to that commit the LEDs didn't turn off at all. Confirming in the spec, these were reversed when introduced. Fix them to match the spec. BugLink: https://gitlab.freedesktop.org/drm/amd/-/issues/1230#note_1021836 Fixes: 5dbf50997578 ("ACPI: PM: s2idle: Add support for new Microsoft UUID") Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI: PM: Add support for upcoming AMD uPEP HID AMDI007Mario Limonciello2021-07-261-2/+8
| | | | | | | | | AMD systems with uPEP HID AMDI007 should be using revision 2 and the AMD method. Fixes: 8fbd6c15ea0a ("ACPI: PM: Adjust behavior for field problems on AMD systems") Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Merge tag 'acpi-5.14-rc1-2' of ↵Linus Torvalds2021-07-071-4/+8
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more ACPI updates from Rafael Wysocki: "These include fixes of the recently introduced support for the Platform Runtime Mechanism (PRM) feature, a new backlight quirk, a suspend-to-idle wakeup fix for non-Intel platforms and a fix for the AMBA bus resource list in /proc/iomem. Specifics: - Fix up the recently added Platform Runtime Mechanism (PRM) support by correnting a couple of implementation mistakes in it and adding a Kconfig help text to describe it (Aubrey Li, Rafael Wysocki). - Add backlight quirk for Dell Vostro 3350 (Hans de Goede). - Avoid spurious wakeups from suspend-to-idle on non-Intel platforms by restricting special EC GPE handling to the Intel ones (Mario Limonciello). - Modify the AMBA bus support in ACPI to avoid adding using resource names in /proc/iomem (Liguang Zhang)" * tag 'acpi-5.14-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI: Do not singal PRM support if not enabled ACPI: Correct \_SB._OSC bit definition for PRM ACPI: Kconfig: Provide help text for the ACPI_PRMT option ACPI: PM: Only mark EC GPE for wakeup on Intel systems ACPI: video: Add quirk for the Dell Vostro 3350 ACPI: AMBA: Fix resource name in /proc/iomem
| * ACPI: PM: Only mark EC GPE for wakeup on Intel systemsMario Limonciello2021-07-011-4/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When using s2idle on a variety of AMD notebook systems, they are experiencing spurious events that the EC or SMU are in the wrong state leading to a hard time waking up or higher than expected power consumption. These events only occur when the EC GPE is inadvertently set as a wakeup source. Originally the EC GPE was only set as a wakeup source when using the intel-vbtn or intel-hid drivers in commit 10a08fd65ec1 ("ACPI: PM: Set up EC GPE for system wakeup from drivers that need it") but during testing a reporter discovered that this was not enough for their ASUS Zenbook UX430UNR/i7-8550U to wakeup by lid event or keypress. Marking the EC GPE for wakeup universally resolved this for that reporter in commit b90ff3554aa3 ("ACPI: PM: s2idle: Always set up EC GPE for system wakeup"). However this behavior has lead to a number of problems: * On both Lenovo T14 and P14s the keyboard wakeup doesn't work, and sometimes the power button event doesn't work. * On HP 635 G7 detaching or attaching AC during suspend will cause the system not to wakeup * On Asus vivobook to prevent detaching AC causing resume problems * On Lenovo 14ARE05 to prevent detaching AC causing resume problems * On HP ENVY x360 to prevent detaching AC causing resume problems As there may be other Intel systems besides ASUS Zenbook UX430UNR/i7-8550U that don't use intel-vbtn or intel-hid, avoid these problems by only universally marking the EC GPE wakesource on non-AMD systems. Link: https://patchwork.kernel.org/project/linux-pm/cover/5997740.FPbUVk04hV@kreacher/#22825489 Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1230 Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1629 Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Acked-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | Merge tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-blockLinus Torvalds2021-06-301-0/+25
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block driver updates from Jens Axboe: "Pretty calm round, mostly just NVMe and a bit of MD: - NVMe updates (via Christoph) - improve the APST configuration algorithm (Alexey Bogoslavsky) - look for StorageD3Enable on companion ACPI device (Mario Limonciello) - allow selecting the network interface for TCP connections (Martin Belanger) - misc cleanups (Amit Engel, Chaitanya Kulkarni, Colin Ian King, Christoph) - move the ACPI StorageD3 code to drivers/acpi/ and add quirks for certain AMD CPUs (Mario Limonciello) - zoned device support for nvmet (Chaitanya Kulkarni) - fix the rules for changing the serial number in nvmet (Noam Gottlieb) - various small fixes and cleanups (Dan Carpenter, JK Kim, Chaitanya Kulkarni, Hannes Reinecke, Wesley Sheng, Geert Uytterhoeven, Daniel Wagner) - MD updates (Via Song) - iostats rewrite (Guoqing Jiang) - raid5 lock contention optimization (Gal Ofri) - Fall through warning fix (Gustavo) - Misc fixes (Gustavo, Jiapeng)" * tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-block: (78 commits) nvmet: use NVMET_MAX_NAMESPACES to set nn value loop: Fix missing discard support when using LOOP_CONFIGURE nvme.h: add missing nvme_lba_range_type endianness annotations nvme: remove zeroout memset call for struct nvme-pci: remove zeroout memset call for struct nvmet: remove zeroout memset call for struct nvmet: add ZBD over ZNS backend support nvmet: add Command Set Identifier support nvmet: add nvmet_req_bio put helper for backends nvmet: add req cns error complete helper block: export blk_next_bio() nvmet: remove local variable nvmet: use nvme status value directly nvmet: use u32 type for the local variable nsid nvmet: use u32 for nvmet_subsys max_nsid nvmet: use req->cmd directly in file-ns fast path nvmet: use req->cmd directly in bdev-ns fast path nvmet: make ver stable once connection established nvmet: allow mn change if subsys not discovered nvmet: make sn stable once connection was established ...
| * ACPI: Add quirks for AMD Renoir/Lucienne CPUs to force the D3 hintMario Limonciello2021-06-161-0/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | AMD systems from Renoir and Lucienne require that the NVME controller is put into D3 over a Modern Standby / suspend-to-idle cycle. This is "typically" accomplished using the `StorageD3Enable` property in the _DSD, but this property was introduced after many of these systems launched and most OEM systems don't have it in their BIOS. On AMD Renoir without these drives going into D3 over suspend-to-idle the resume will fail with the NVME controller being reset and a trace like this in the kernel logs: ``` [ 83.556118] nvme nvme0: I/O 161 QID 2 timeout, aborting [ 83.556178] nvme nvme0: I/O 162 QID 2 timeout, aborting [ 83.556187] nvme nvme0: I/O 163 QID 2 timeout, aborting [ 83.556196] nvme nvme0: I/O 164 QID 2 timeout, aborting [ 95.332114] nvme nvme0: I/O 25 QID 0 timeout, reset controller [ 95.332843] nvme nvme0: Abort status: 0x371 [ 95.332852] nvme nvme0: Abort status: 0x371 [ 95.332856] nvme nvme0: Abort status: 0x371 [ 95.332859] nvme nvme0: Abort status: 0x371 [ 95.332909] PM: dpm_run_callback(): pci_pm_resume+0x0/0xe0 returns -16 [ 95.332936] nvme 0000:03:00.0: PM: failed to resume async: error -16 ``` The Microsoft documentation for StorageD3Enable mentioned that Windows has a hardcoded allowlist for D3 support, which was used for these platforms. Introduce quirks to hardcode them for Linux as well. As this property is now "standardized", OEM systems using AMD Cezanne and newer APU's have adopted this property, and quirks like this should not be necessary. CC: Shyam-sundar S-k <Shyam-sundar.S-k@amd.com> CC: Alexander Deucher <Alexander.Deucher@amd.com> CC: Prike Liang <prike.liang@amd.com> Link: https://docs.microsoft.com/en-us/windows-hardware/design/component-guidelines/power-management-for-storage-hardware-devices-intro Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Julian Sikorski <belegdol@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
* | ACPI: PM: Adjust behavior for field problems on AMD systemsMario Limonciello2021-06-181-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some AMD Systems with uPEP _HID AMD004/AMDI005 have an off by one bug in their function mask return. This means that they will call entrance but not exit for matching functions. Other AMD systems with this HID should use the Microsoft generic UUID. AMD systems with uPEP HID AMDI006 should be using the Microsoft method. Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Tested-by: Julian Sikorski <belegdol@gmail.com> Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | ACPI: PM: s2idle: Add support for new Microsoft UUIDPratik Vishwakarma2021-06-181-4/+30
| | | | | | | | | | | | | | | | | | | | | | | | This adds supports for _DSM notifications to the Microsoft UUID described by Microsoft documentation for s2idle. Link: https://docs.microsoft.com/en-us/windows-hardware/design/device-experiences/modern-standby-firmware-notifications Co-developed-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Pratik Vishwakarma <Pratik.Vishwakarma@amd.com> Tested-by: Julian Sikorski <belegdol@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | ACPI: PM: s2idle: Add support for multiple func maskPratik Vishwakarma2021-06-181-11/+20
| | | | | | | | | | | | | | | | | | | | Required for follow-up patch adding new UUID needing new function mask. Signed-off-by: Pratik Vishwakarma <Pratik.Vishwakarma@amd.com> Tested-by: Julian Sikorski <belegdol@gmail.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | ACPI: PM: s2idle: Refactor common codePratik Vishwakarma2021-06-181-32/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Refactor common code to prepare for upcoming changes. * Remove unused struct. * Print error before returning. * Frees ACPI obj if _DSM type is not as expected. * Treat lps0_dsm_func_mask as an integer rather than character * Remove extra out_obj * Move rev_id Co-developed-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Pratik Vishwakarma <Pratik.Vishwakarma@amd.com> Tested-by: Julian Sikorski <belegdol@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | ACPI: PM: s2idle: Use correct revision idPratik Vishwakarma2021-06-181-1/+1
| | | | | | | | | | | | | | | | | | AMD spec mentions only revision 0. With this change, device constraint list is populated properly. Signed-off-by: Pratik Vishwakarma <Pratik.Vishwakarma@amd.com> Tested-by: Julian Sikorski <belegdol@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | ACPI: PM: s2idle: Add missing LPS0 functions for AMDAlex Deucher2021-05-171-0/+4
|/ | | | | | | | | | | | | These are supposedly not required for AMD platforms, but at least some HP laptops seem to require it to properly turn off the keyboard backlight. Based on a patch from Marcin Bachry <hegel666@gmail.com>. Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1230 Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI: PM: s2idle: Drop unused local variables and related codeRafael J. Wysocki2021-01-071-13/+1
| | | | | | | | Two local variables in drivers/acpi/x86/s2idle.c are never read, so drop them along with the code updating their values (in vain). Fixes: fef98671194b ("ACPI: PM: s2idle: Move x86-specific code to the x86 directory") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI: PM: s2idle: Move x86-specific code to the x86 directoryRafael J. Wysocki2020-12-171-0/+460
| | | | | | | | | | | | | | | | | | Some code in drivers/acpi/sleep.c (which is regarded as a generic file) related to suspend-to-idle support has grown direct dependencies on x86, but in fact it has been specific to x86 (which is the only user of it) anyway for a long time. For this reason, move that code to a separate file under acpi/x86/ and make it build and run as before under the right conditions. While at it, rename a vendor checking function in that code and consistently use acpi_handle_debug() for printing debug-related information in it. No expected functional impact. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI: Convert to new X86 CPU match macrosThomas Gleixner2020-03-241-10/+10
| | | | | | | | | | | | | The new macro set has a consistent namespace and uses C99 initializers instead of the grufty C89 ones. Rename the local macro wrapper to X86_MATCH for consistency. It stays for readability sake. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lkml.kernel.org/r/20200320131509.467730627@linutronix.de
* x86/intel: Aggregate big core mobile namingPeter Zijlstra2019-08-281-2/+2
| | | | | | | | | | | | | | | | | | | | | | | Currently big core mobile chips have either: - _L - _ULT - _MOBILE Make it uniformly: _L. for i in `git grep -l "\(INTEL_FAM6_\|VULNWL_INTEL\|INTEL_CPU_FAM6\).*_\(MOBILE\|ULT\)"` do sed -i -e 's/\(\(INTEL_FAM6_\|VULNWL_INTEL\|INTEL_CPU_FAM6\).*\)_\(MOBILE\|ULT\)/\1_L/g' ${i} done Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Tony Luck <tony.luck@intel.com> Cc: x86@kernel.org Cc: Dave Hansen <dave.hansen@intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190827195122.568978530@infradead.org
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner2019-06-192-8/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ACPI / x86: Make PWM2 device always present at Lenovo Yoga BookYauhen Kharuzhy2019-02-151-0/+5
| | | | | | | | | | | Lenovo Yoga Book uses PWM2 for controlling keyboard backlight but this device is hidden in the DSDT in Windows version of notebook (if OSID == 1). Make this device always present for this notebook. Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Merge tag 'pci-v4.20-changes' of ↵Linus Torvalds2018-10-251-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: - Fix ASPM link_state teardown on removal (Lukas Wunner) - Fix misleading _OSC ASPM message (Sinan Kaya) - Make _OSC optional for PCI (Sinan Kaya) - Don't initialize ASPM link state when ACPI_FADT_NO_ASPM is set (Patrick Talbert) - Remove x86 and arm64 node-local allocation for host bridge structures (Punit Agrawal) - Pay attention to device-specific _PXM node values (Jonathan Cameron) - Support new Immediate Readiness bit (Felipe Balbi) - Differentiate between pciehp surprise and safe removal (Lukas Wunner) - Remove unnecessary pciehp includes (Lukas Wunner) - Drop pciehp hotplug_slot_ops wrappers (Lukas Wunner) - Tolerate PCIe Slot Presence Detect being hardwired to zero to workaround broken hardware, e.g., the Wilocity switch/wireless device (Lukas Wunner) - Unify pciehp controller & slot structs (Lukas Wunner) - Constify hotplug_slot_ops (Lukas Wunner) - Drop hotplug_slot_info (Lukas Wunner) - Embed hotplug_slot struct into users instead of allocating it separately (Lukas Wunner) - Initialize PCIe port service drivers directly instead of relying on initcall ordering (Keith Busch) - Restore PCI config state after a slot reset (Keith Busch) - Save/restore DPC config state along with other PCI config state (Keith Busch) - Reference count devices during AER handling to avoid race issue with concurrent hot removal (Keith Busch) - If an Upstream Port reports ERR_FATAL, don't try to read the Port's config space because it is probably unreachable (Keith Busch) - During error handling, use slot-specific reset instead of secondary bus reset to avoid link up/down issues on hotplug ports (Keith Busch) - Restore previous AER/DPC handling that does not remove and re-enumerate devices on ERR_FATAL (Keith Busch) - Notify all drivers that may be affected by error recovery resets (Keith Busch) - Always generate error recovery uevents, even if a driver doesn't have error callbacks (Keith Busch) - Make PCIe link active reporting detection generic (Keith Busch) - Support D3cold in PCIe hierarchies during system sleep and runtime, including hotplug and Thunderbolt ports (Mika Westerberg) - Handle hpmemsize/hpiosize kernel parameters uniformly, whether slots are empty or occupied (Jon Derrick) - Remove duplicated include from pci/pcie/err.c and unused variable from cpqphp (YueHaibing) - Remove driver pci_cleanup_aer_uncorrect_error_status() calls (Oza Pawandeep) - Uninline PCI bus accessors for better ftracing (Keith Busch) - Remove unused AER Root Port .error_resume method (Keith Busch) - Use kfifo in AER instead of a local version (Keith Busch) - Use threaded IRQ in AER bottom half (Keith Busch) - Use managed resources in AER core (Keith Busch) - Reuse pcie_port_find_device() for AER injection (Keith Busch) - Abstract AER interrupt handling to disconnect error injection (Keith Busch) - Refactor AER injection callbacks to simplify future improvments (Keith Busch) - Remove unused Netronome NFP32xx Device IDs (Jakub Kicinski) - Use bitmap_zalloc() for dma_alias_mask (Andy Shevchenko) - Add switch fall-through annotations (Gustavo A. R. Silva) - Remove unused Switchtec quirk variable (Joshua Abraham) - Fix pci.c kernel-doc warning (Randy Dunlap) - Remove trivial PCI wrappers for DMA APIs (Christoph Hellwig) - Add Intel GPU device IDs to spurious interrupt quirk (Bin Meng) - Run Switchtec DMA aliasing quirk only on NTB endpoints to avoid useless dmesg errors (Logan Gunthorpe) - Update Switchtec NTB documentation (Wesley Yung) - Remove redundant "default n" from Kconfig (Bartlomiej Zolnierkiewicz) - Avoid panic when drivers enable MSI/MSI-X twice (Tonghao Zhang) - Add PCI support for peer-to-peer DMA (Logan Gunthorpe) - Add sysfs group for PCI peer-to-peer memory statistics (Logan Gunthorpe) - Add PCI peer-to-peer DMA scatterlist mapping interface (Logan Gunthorpe) - Add PCI configfs/sysfs helpers for use by peer-to-peer users (Logan Gunthorpe) - Add PCI peer-to-peer DMA driver writer's documentation (Logan Gunthorpe) - Add block layer flag to indicate driver support for PCI peer-to-peer DMA (Logan Gunthorpe) - Map Infiniband scatterlists for peer-to-peer DMA if they contain P2P memory (Logan Gunthorpe) - Register nvme-pci CMB buffer as PCI peer-to-peer memory (Logan Gunthorpe) - Add nvme-pci support for PCI peer-to-peer memory in requests (Logan Gunthorpe) - Use PCI peer-to-peer memory in nvme (Stephen Bates, Steve Wise, Christoph Hellwig, Logan Gunthorpe) - Cache VF config space size to optimize enumeration of many VFs (KarimAllah Ahmed) - Remove unnecessary <linux/pci-ats.h> include (Bjorn Helgaas) - Fix VMD AERSID quirk Device ID matching (Jon Derrick) - Fix Cadence PHY handling during probe (Alan Douglas) - Signal Cadence Endpoint interrupts via AXI region 0 instead of last region (Alan Douglas) - Write Cadence Endpoint MSI interrupts with 32 bits of data (Alan Douglas) - Remove redundant controller tests for "device_type == pci" (Rob Herring) - Document R-Car E3 (R8A77990) bindings (Tho Vu) - Add device tree support for R-Car r8a7744 (Biju Das) - Drop unused mvebu PCIe capability code (Thomas Petazzoni) - Add shared PCI bridge emulation code (Thomas Petazzoni) - Convert mvebu to use shared PCI bridge emulation (Thomas Petazzoni) - Add aardvark Root Port emulation (Thomas Petazzoni) - Support 100MHz/200MHz refclocks for i.MX6 (Lucas Stach) - Add initial power management for i.MX7 (Leonard Crestez) - Add PME_Turn_Off support for i.MX7 (Leonard Crestez) - Fix qcom runtime power management error handling (Bjorn Andersson) - Update TI dra7xx unaligned access errata workaround for host mode as well as endpoint mode (Vignesh R) - Fix kirin section mismatch warning (Nathan Chancellor) - Remove iproc PAXC slot check to allow VF support (Jitendra Bhivare) - Quirk Keystone K2G to limit MRRS to 256 (Kishon Vijay Abraham I) - Update Keystone to use MRRS quirk for host bridge instead of open coding (Kishon Vijay Abraham I) - Refactor Keystone link establishment (Kishon Vijay Abraham I) - Simplify and speed up Keystone link training (Kishon Vijay Abraham I) - Remove unused Keystone host_init argument (Kishon Vijay Abraham I) - Merge Keystone driver files into one (Kishon Vijay Abraham I) - Remove redundant Keystone platform_set_drvdata() (Kishon Vijay Abraham I) - Rename Keystone functions for uniformity (Kishon Vijay Abraham I) - Add Keystone device control module DT binding (Kishon Vijay Abraham I) - Use SYSCON API to get Keystone control module device IDs (Kishon Vijay Abraham I) - Clean up Keystone PHY handling (Kishon Vijay Abraham I) - Use runtime PM APIs to enable Keystone clock (Kishon Vijay Abraham I) - Clean up Keystone config space access checks (Kishon Vijay Abraham I) - Get Keystone outbound window count from DT (Kishon Vijay Abraham I) - Clean up Keystone outbound window configuration (Kishon Vijay Abraham I) - Clean up Keystone DBI setup (Kishon Vijay Abraham I) - Clean up Keystone ks_pcie_link_up() (Kishon Vijay Abraham I) - Fix Keystone IRQ status checking (Kishon Vijay Abraham I) - Add debug messages for all Keystone errors (Kishon Vijay Abraham I) - Clean up Keystone includes and macros (Kishon Vijay Abraham I) - Fix Mediatek unchecked return value from devm_pci_remap_iospace() (Gustavo A. R. Silva) - Fix Mediatek endpoint/port matching logic (Honghui Zhang) - Change Mediatek Root Port Class Code to PCI_CLASS_BRIDGE_PCI (Honghui Zhang) - Remove redundant Mediatek PM domain check (Honghui Zhang) - Convert Mediatek to pci_host_probe() (Honghui Zhang) - Fix Mediatek MSI enablement (Honghui Zhang) - Add Mediatek system PM support for MT2712 and MT7622 (Honghui Zhang) - Add Mediatek loadable module support (Honghui Zhang) - Detach VMD resources after stopping root bus to prevent orphan resources (Jon Derrick) - Convert pcitest build process to that used by other tools (iio, perf, etc) (Gustavo Pimentel) * tag 'pci-v4.20-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (140 commits) PCI/AER: Refactor error injection fallbacks PCI/AER: Abstract AER interrupt handling PCI/AER: Reuse existing pcie_port_find_device() interface PCI/AER: Use managed resource allocations PCI: pcie: Remove redundant 'default n' from Kconfig PCI: aardvark: Implement emulated root PCI bridge config space PCI: mvebu: Convert to PCI emulated bridge config space PCI: mvebu: Drop unused PCI express capability code PCI: Introduce PCI bridge emulated config space common logic PCI: vmd: Detach resources after stopping root bus nvmet: Optionally use PCI P2P memory nvmet: Introduce helper functions to allocate and free request SGLs nvme-pci: Add support for P2P memory in requests nvme-pci: Use PCI p2pmem subsystem to manage the CMB IB/core: Ensure we map P2P memory correctly in rdma_rw_ctx_[init|destroy]() block: Add PCI P2P flag for request queue PCI/P2PDMA: Add P2P DMA driver writer's documentation docs-rst: Add a new directory for PCI documentation PCI/P2PDMA: Introduce configfs/sysfs enable attribute helpers PCI/P2PDMA: Add PCI p2pmem DMA mappings to adjust the bus offset ...
| * ACPI / property: Allow multiple property compatible _DSD entriesMika Westerberg2018-10-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is possible to have _DSD entries where the data is compatible with device properties format but are using different GUID for various reasons. In addition to that there can be many such _DSD entries for a single device such as for PCIe root port used to host a Thunderbolt hierarchy: Scope (\_SB.PCI0.RP21) { Name (_DSD, Package () { ToUUID ("6211e2c0-58a3-4af3-90e1-927a4e0c55a4"), Package () { Package () {"HotPlugSupportInD3", 1} }, ToUUID ("efcc06cc-73ac-4bc3-bff0-76143807c389"), Package () { Package () {"ExternalFacingPort", 1}, Package () {"UID", 0 } } }) } More information about these new _DSD entries can be found in: https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports To make these available for drivers via unified device property APIs, modify ACPI property core so that it supports multiple _DSD entries organized in a linked list. We also store GUID of each _DSD entry in struct acpi_device_properties in case there is need to differentiate between entries. The supported GUIDs are then listed in prp_guids array. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
* | Merge branch 'perf-core-for-linus' of ↵Linus Torvalds2018-10-231-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "The main updates in this cycle were: - Lots of perf tooling changes too voluminous to list (big perf trace and perf stat improvements, lots of libtraceevent reorganization, etc.), so I'll list the authors and refer to the changelog for details: Benjamin Peterson, Jérémie Galarneau, Kim Phillips, Peter Zijlstra, Ravi Bangoria, Sangwon Hong, Sean V Kelley, Steven Rostedt, Thomas Gleixner, Ding Xiang, Eduardo Habkost, Thomas Richter, Andi Kleen, Sanskriti Sharma, Adrian Hunter, Tzvetomir Stoyanov, Arnaldo Carvalho de Melo, Jiri Olsa. ... with the bulk of the changes written by Jiri Olsa, Tzvetomir Stoyanov and Arnaldo Carvalho de Melo. - Continued intel_rdt work with a focus on playing well with perf events. This also imported some non-perf RDT work due to dependencies. (Reinette Chatre) - Implement counter freezing for Arch Perfmon v4 (Skylake and newer). This allows to speed up the PMI handler by avoiding unnecessary MSR writes and make it more accurate. (Andi Kleen) - kprobes cleanups and simplification (Masami Hiramatsu) - Intel Goldmont PMU updates (Kan Liang) - ... plus misc other fixes and updates" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (155 commits) kprobes/x86: Use preempt_enable() in optimized_callback() x86/intel_rdt: Prevent pseudo-locking from using stale pointers kprobes, x86/ptrace.h: Make regs_get_kernel_stack_nth() not fault on bad stack perf/x86/intel: Export mem events only if there's PEBS support x86/cpu: Drop pointless static qualifier in punit_dev_state_show() x86/intel_rdt: Fix initial allocation to consider CDP x86/intel_rdt: CBM overlap should also check for overlap with CDP peer x86/intel_rdt: Introduce utility to obtain CDP peer tools lib traceevent, perf tools: Move struct tep_handler definition in a local header file tools lib traceevent: Separate out tep_strerror() for strerror_r() issues perf python: More portable way to make CFLAGS work with clang perf python: Make clang_has_option() work on Python 3 perf tools: Free temporary 'sys' string in read_event_files() perf tools: Avoid double free in read_event_file() perf tools: Free 'printk' string in parse_ftrace_printk() perf tools: Cleanup trace-event-info 'tdata' leak perf strbuf: Match va_{add,copy} with va_end perf test: S390 does not support watchpoints in test 22 perf auxtrace: Include missing asm/bitsperlong.h to get BITS_PER_LONG tools include: Adopt linux/bits.h ...
| * | x86/cpu: Sanitize FAM6_ATOM namingPeter Zijlstra2018-10-021-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Going primarily by: https://en.wikipedia.org/wiki/List_of_Intel_Atom_microprocessors with additional information gleaned from other related pages; notably: - Bonnell shrink was called Saltwell - Moorefield is the Merriefield refresh which makes it Airmont The general naming scheme is: FAM6_ATOM_UARCH_SOCTYPE for i in `git grep -l FAM6_ATOM` ; do sed -i -e 's/ATOM_PINEVIEW/ATOM_BONNELL/g' \ -e 's/ATOM_LINCROFT/ATOM_BONNELL_MID/' \ -e 's/ATOM_PENWELL/ATOM_SALTWELL_MID/g' \ -e 's/ATOM_CLOVERVIEW/ATOM_SALTWELL_TABLET/g' \ -e 's/ATOM_CEDARVIEW/ATOM_SALTWELL/g' \ -e 's/ATOM_SILVERMONT1/ATOM_SILVERMONT/g' \ -e 's/ATOM_SILVERMONT2/ATOM_SILVERMONT_X/g' \ -e 's/ATOM_MERRIFIELD/ATOM_SILVERMONT_MID/g' \ -e 's/ATOM_MOOREFIELD/ATOM_AIRMONT_MID/g' \ -e 's/ATOM_DENVERTON/ATOM_GOLDMONT_X/g' \ -e 's/ATOM_GEMINI_LAKE/ATOM_GOLDMONT_PLUS/g' ${i} done Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: dave.hansen@linux.intel.com Cc: len.brown@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* / ACPI / property: Switch to bitmap_zalloc()Andy Shevchenko2018-09-101-2/+2
|/ | | | | | | | | Switch to bitmap_zalloc() to show clearly what we are allocating. Besides that it returns pointer of bitmap type instead of opaque void *. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI / x86: utils: Remove status workaround from acpi_device_always_present()Hans de Goede2018-08-091-10/+0
| | | | | | | | | | Now that we init the status field to ACPI_STA_DEFAULT rather then to 0, the workaround for acpi_match_device_ids() always returning -ENOENT when status is 0 is no longer needed. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI / x86: enable touchscreen on Dell Venue Pro 7139Tristian Celestin2018-07-041-3/+9
| | | | | | | | | | Permanently enable the SYNA7500 touchscreen device on the Dell Venue Pro 7139. The DSDT hides the touchscreen ACPI device on the 7139 in the same fashion as the 7130, and needs to be enabled in the same way. Signed-off-by: Tristian Celestin <tristiancelestin@fastmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI / x86: Extend KIOX000A quirk to cover all affected BIOS versionsHans de Goede2017-10-211-1/+17
| | | | | | | | | | | | | | | | | | Recently produced GPD win devices have a new BIOS, research into the changes in this BIOS has found a ChangeLog which shows that the disabling of the KIOX000A node has been done starting with the 20170221 version. Unfortunately the GPD pocket uses the exact same DMI strings as the win and its BIOS was copy-pasted from the GPD win, so it has a disabled KIOX000A node which we should not enable, so we need to check for the exact BIOS date. This commit adds 2 extra entries to the always_present_ids quirk table with bios_date matches for the older also affected and the latest BIOS. Reported-by: ReddestDream <reddestdream@gmail.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI / property: Support Apple _DSM propertiesLukas Wunner2017-08-031-0/+141
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While the rest of the world has standardized on _DSD as the way to store device properties in AML (introduced with ACPI 5.1 in 2014), Apple has been using a custom _DSM to achieve the same for much longer (ever since they switched from DeviceTree-based PowerPC to Intel in 2005, verified with MacOS X 10.4.11). The theory of operation on macOS is as follows: AppleACPIPlatform.kext invokes mergeEFIproperties() and mergeDSMproperties() for each device to merge properties conveyed by EFI drivers as well as properties stored in AML into the I/O Kit registry from which they can be retrieved by drivers. We've been supporting EFI properties since commit 58c5475aba67 ("x86/efi: Retrieve and assign Apple device properties"). The present commit adds support for _DSM properties, thereby completing our support for Apple device properties. The _DSM properties are made available under the primary fwnode, the EFI properties under the secondary fwnode. So for devices which possess both property types, they can all be elegantly accessed with the uniform API in <linux/property.h>. Until recently we had no need to support _DSM properties, they contained only uninteresting garbage. The situation has changed with MacBooks and MacBook Pros introduced since 2015: Their keyboard is attached with SPI instead of USB and the _CRS data which is necessary to initialize the spi driver only contains valid information if OSPM responds "false" to _OSI("Darwin"). If OSPM responds "true", _CRS is empty and the spi driver fails to initialize. The rationale is very simple, Apple only cares about macOS and Windows: On Windows, _CRS contains valid data, whereas on macOS it is empty. Instead, macOS gleans the necessary data from the _DSM properties. Since Linux deliberately defaults to responding "true" to _OSI("Darwin"), we need to emulate macOS' behaviour by initializing the spi driver with data returned by the _DSM. An out-of-tree driver for the SPI keyboard exists which currently binds to the ACPI device, invokes the _DSM, parses the returned package and instantiates an SPI device with the data gleaned from the _DSM: https://github.com/cb22/macbook12-spi-driver/commit/9a416d699ef4 https://github.com/cb22/macbook12-spi-driver/commit/0c34936ed9a1 By adding support for Apple's _DSM properties in generic ACPI code, the out-of-tree driver will be able to register as a regular SPI driver, significantly reducing its amount of code and improving its chances to be mainlined. The SPI keyboard will not be the only user of this commit: E.g. on the MacBook8,1, the UART-attached Bluetooth device likewise returns empty _CRS data if OSPM returns "true" to _OSI("Darwin"). The _DSM returns a Package whose format unfortunately deviates slightly from the _DSD spec: The properties are marshalled up in a single Package as alternating key/value elements, unlike _DSD which stores them as a Package of 2-element Packages. The present commit therefore converts the Package to _DSD format and the ACPI core can then treat the data as if Apple would follow the standard. Well, except for one small annoyance: The properties returned by the _DSM only ever have one of two types, Integer or Buffer. The former is retrievable as usual with device_property_read_u64(), but the latter is not part of the _DSD spec and it is not possible to retrieve Buffer properties with the device_property_read_*() functions due to the type checking performed in drivers/acpi/property.c. It is however possible to retrieve them with acpi_dev_get_property(). Apple is using the Buffer type somewhat sloppily to store null-terminated strings but also integers. The real data type is not distinguishable by the ACPI core and the onus is on the caller to use the contents of the Buffer in an appropriate way. In case Apple moves to _DSD in the future, this commit first checks for _DSD and falls back to _DSM only if _DSD is not found. Tested-by: Ronald Tschalär <ronald@innovation.ch> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI / x86: Add KIOX000A accelerometer on GPD win to always_present_ids arrayHans de Goede2017-07-121-0/+13
| | | | | | | | | | | | | The GPD win BIOS dated 20170320 has disabled the accelerometer, the drivers sometimes cause crashes under Windows and this is how the manufacturer has solved this :| I see no other way to keep the accelerometer working under Windows then adding it to the always_present_ids array. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI / x86: Add Dell Venue 11 Pro 7130 touchscreen to always_present_idsHans de Goede2017-07-121-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The _STA method of the Venue 11 Pro 7130 touchscreen has this ugliness: Method (_STA, 0, NotSerialized) // _STA: Status { If ((SDS1 & One) == One) { If (RST1 == Zero) { Return (0x0F) } ElseIf (RST2 == Zero) { RST2 = One TMRV = Timer } Else { Local0 = ((Timer - TMRV) / 0x2710) If (Local0 > TMRI) { RST2 = Zero RST1 = Zero } } } Else { Return (Zero) } } Whereby RST1 gets set by _SB.PCI0.GFX0.LCD.LCD1._ON, this means that after RST1 has been set first _STA must be called to set TIMER and then after enough time has elapsed _STA must be called twice more, once to clear RST1 and once to finally return 0xf before the touchscreen will show up. Which is just crazy. This commit adds an always_present_ids entry for the SYNA7500 touchscreen ACPI node, together with a DMI match for the Venue 11 Pro 7130, fixing the touchscreen not working on this device. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI / x86: Allow matching always_present_id array entries by DMIHans de Goede2017-07-121-4/+15
| | | | | | | | | | | | | | | | | | | On some x86 systems the DSDT hides APCI devices to work around Windows driver bugs. On one such system the device is even hidden until a certain time after _SB.PCI0.GFX0.LCD.LCD1._ON gets called has passed *and* _STA has been called at least 3 times since. TL;DR: it is a mess. Until now the always_present_id matching was used to force status for a whole class of devices, e.g. always enable PWM1 on CHerry Trail devices. This commit extends the always_present_id matching code to optionally also check for a DMI match so that we can also add system specific quirks to the always_present_id array. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI / bus: Add INT0002 to list of always-present devicesHans de Goede2017-04-271-0/+5
| | | | | | | | | The INT0002 device is necessary to clear wakeup interrupt sources on Cherry Trail devices, without it we get nobody cared IRQ msgs and some systems don't properly resume at all without it. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* ACPI / bus: Introduce a list of ids for "always present" devicesHans de Goede2017-04-271-0/+85
Several Bay / Cherry Trail devices (all of which ship with Windows 10) hide the LPSS PWM controller in ACPI, typically the _STA method looks like this: Method (_STA, 0, NotSerialized) // _STA: Status { If (OSID == One) { Return (Zero) } Return (0x0F) } Where OSID is some dark magic seen in all Cherry Trail ACPI tables making the machine behave differently depending on which OS it *thinks* it is booting, this gets set in a number of ways which we cannot control, on some newer machines it simple hardcoded to "One" aka win10. This causes the PWM controller to get hidden, which means Linux cannot control the backlight level on cht based tablets / laptops. Since loading the driver for this does no harm (the only in kernel user of it is the i915 driver, which will only uses it when it needs it), this commit makes acpi_bus_get_status() always set status to ACPI_STA_DEFAULT for the LPSS PWM device, fixing the lack of backlight control. Signed-off-by: Hans de Goede <hdegoede@redhat.com> [ rjw: Rename the new file to utils.c ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>