kernel/drivers/acpi/acpi_platform.c, branch master

ACPI: video: Switch over to auxiliary bus type

2026-03-10T14:08:21Z

Commit 02c057ddefef ("ACPI: video: Convert the driver to a platform one") switched over the ACPI video bus driver from an ACPI driver to a platform driver, but that change introduced an unwanted and unexpected side effect. Namely, on some systems, the ACPI device object of the ACPI video bus device is an ACPI companion of multiple platform devices and, after adding video_device_ids[] as an acpi_match_table to the acpi_video_bus platform driver, all of those devices started to match that driver and its probe callback is invoked for all of them (it fails, but it leaves a confusing message in the log). Moreover, the MODULE_DEVICE_TABLE() of the ACPI video driver module matches all of the devices sharing the ACPI companion with the ACPI video bus device. To address this, make the core ACPI device enumeration code create an auxiliary device for the ACPI video bus device object instead of a platform device and switch over the ACPI video bus driver (once more) to an auxiliary driver. Auxiliary driver generally is a better match for ACPI video bus than platform driver, among other things because the ACPI video bus device does not require any resources to be allocated for it during enumeration. It also allows the ACPI video bus driver to stop abusing device matching based on ACPI device IDs and it allows a special case to be dropped from acpi_create_platform_device() because that function need not worry about the ACPI video bus device any more. Fixes: 02c057ddefef ("ACPI: video: Convert the driver to a platform one") Reported-by: Pratap Nirujogi Closes: https://lore.kernel.org/linux-acpi/007e3390-6b2b-457e-83c7-c794c5952018@amd.com/ Tested-by: Pratap Nirujogi Signed-off-by: Rafael J. Wysocki Reviewed-by: Mario Limonciello (AMD) [ rjw: Added AUXILIARY_BUS selection to CONFIG_ACPI to fix build issue ] [ rjw: Fixed error path in acpi_create_video_bus_device() ] Link: https://patch.msgid.link/5986516.DvuYhMxLoT@rafael.j.wysocki Signed-off-by: Rafael J. Wysocki

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51Z

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28Z

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

ACPI: scan: Clean up after recent changes

2026-01-15T13:27:38Z

Use LIST_HEAD() for initializing an on-stack list head in two places and remove an empty code line added by mistake. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Mario Limonciello (AMD) Link: https://patch.msgid.link/12825056.O9o76ZdvQC@rafael.j.wysocki

ACPI: scan: Register platform devices for backlight device objects

2026-01-15T13:26:34Z

ACPI device objects associated with backlight interfaces are special because they are ACPI companions of PCI devices (GPUs), but the interfaces exposed by them resemble platform device one. Currently, the ACPI video driver binds to them with the help of a special "synthetic" device ID regardless of the pairing with the PCI devices, but since it is generally better to use platform drivers for handling such interfaces, the plan is to convert that drviver into a platform one. However, for this purpose, platform devices corresponding to the ACPI backlight device objects need to be registered, so update acpi_bus_attach() to apply the default ACPI enumeration to them and modify acpi_create_platform_device() to avoid bailing out early if a "physical" device is already attached to a backlight ACPI device object. In addition, update acpi_companion_match() to return a valid struct acpi_device pointer if the ACPI companion of the given device is a backlight ACPI device object, which will facilitate driver matching for platform devices corresponding to those objects. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Armin Wolf Link: https://patch.msgid.link/5081593.31r3eYUQgx@rafael.j.wysocki

ACPI: scan: Register platform devices for fixed event buttons

2025-12-26T14:08:56Z

On platforms using ACPI, power and sleep buttons may be so called "fixed event devices" in which case they are hooked up directly to the Fixed Events register in the platform via dedicated lines and there are no corresponding device objects in the ACPI namespace. Nevertheless, in Linux they get corresponding struct acpi_device objects with special device IDs, either LNXPWRBN or LNXSLPBN, which are then used for driver binding in a ususal way. However, the function creating those struct acpi_device objects for "fixed event device" buttons, acpi_bus_scan_fixed(), does not register platform devices for them, unlike the generic code handling device enumeration based on the ACPI namespace. Consequently, if an ACPI power or sleep button is represented by a device object in the ACPI namespace, it will get a corresponding platform device, but if it is a "fixed event device", it will not get one, which is inconsistent and prevents the ACPI power button driver from being converted into a platform driver. For the sake of consistency and to allow the ACPI power button driver to become a platform one going forward, modify acpi_bus_scan_fixed() to register platform devices for "fixed event device" buttons and update ACPI platform device registration code to work with non-device ACPI object types, so it can handle the buttons in question. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/3731144.R56niFO833@rafael.j.wysocki

ACPI: platform: Move SMB0001 HID to the header and reuse

2023-07-04T17:28:20Z

There are at least two places in the kernel that are using the SMB0001 HID. Make it to be available via acpi_drivers.h header file. While at it, replace hard coded one with a definition. Reviewed-by: Andi Shyti Acked-by: Wolfram Sang # for I2C Link: https://lore.kernel.org/r/20230621151652.79579-2-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko Signed-off-by: Rafael J. Wysocki

ACPI: platform: Ignore SMB0001 only when it has resources

2023-07-04T17:28:20Z

After switching i2c-scmi driver to be a platform one, it stopped being enumerated on number of Kontron platforms, because it's listed in the forbidden_id_list. To resolve the situation, add a flag to driver data to allow devices with no resources in _CRS to be enumerated via platform bus. Fixes: 03d4287add6e ("i2c: scmi: Convert to be a platform driver") Closes: https://lore.kernel.org/r/60c1756765b9a3f1eab0dcbd84f59f00fe1caf48.camel@kontron.com Link: https://lore.kernel.org/r/20230621151652.79579-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko Reviewed-by: Andi Shyti [ rjw: Move has_resource definition to the block in which it is used and initialize it to 'false' ] Signed-off-by: Rafael J. Wysocki

Merge branches 'acpi-scan', 'acpi-bus' and 'acpi-platform'

2022-09-30T18:28:22Z

Merge changes related to ACPI device enumeration and ACPI support for platform devices for 6.1-rc1: - Clean up ACPI platform devices support code (Andy Shevchenko, John Garry). - Clean up ACPI bus management code (Andy Shevchenko, ye xingchen). - Add support for multiple DMA windows with different offsets to the ACPI device enumeration code and use it on LoongArch (Jianmin Lv). * acpi-scan: LoongArch: Use acpi_arch_dma_setup() and remove ARCH_HAS_PHYS_TO_DMA ACPI: scan: Support multiple DMA windows with different offsets * acpi-bus: ACPI: bus: Refactor ACPI matching functions for better readability ACPI: bus: Drop kernel doc annotation from acpi_bus_notify() ACPI: bus: Remove the unneeded result variable * acpi-platform: ACPI: platform: Use PLATFORM_DEVID_NONE in acpi_create_platform_device() ACPI: platform: Sort forbidden_id_list[] in ascending order ACPI: platform: Use sizeof(*pointer) instead of sizeof(type) ACPI: platform: Remove redundant print on -ENOMEM ACPI: platform: Get rid of redundant 'else'

ACPI: platform: Use PLATFORM_DEVID_NONE in acpi_create_platform_device()

2022-09-03T18:55:25Z

Instead of hardcoding the value for the id, use PLATFORM_DEVID_NONE. Signed-off-by: John Garry Reviewed-by: Andy Shevchenko Signed-off-by: Rafael J. Wysocki