kernel/linux.git/drivers/acpi/button.c, branch v7.2-rc1

ACPI: button: Switch over to devres-based resource management

2026-06-02T19:07:51+00:00

Switch over the ACPI button driver to devres-based resource management by making the following changes: * Use devm_kzalloc() for allocating button object memory. * Use devm_input_allocate_device() for allocating the input class device object. * Turn acpi_lid_remove_fs() into a devm cleanup action added by devm_acpi_lid_add_fs() which is a new wrapper around acpi_lid_add_fs(). * Add devm_acpi_button_init_wakeup() for initializing the wakeup source and make it add a custom devm action that will automatically remove the wakeup source registered by it. * Turn acpi_button_remove_event_handler() into a devm cleanup action added by devm_acpi_button_add_event_handler() which is a new wrapper around acpi_button_add_event_handler(). No intentional functional impact. Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/2283436.Mh6RI2rZIc@rafael.j.wysocki [ rjw: Rebased and removed unnecessary input device parent assignment ] Signed-off-by: Rafael J. Wysocki

ACPI: button: Reorganize installing and removing event handlers

2026-06-02T19:07:10+00:00

To facilitate subsequent changes, move the code installing and removing button event handlers into two separate functions called acpi_button_add_event_handler() and acpi_button_remove_event_handler(), respectively, and rearrange it to reduce code duplication. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/2714170.Lt9SDvczpP@rafael.j.wysocki

ACPI: button: Use string literals for generating netlink messages

2026-06-02T19:07:09+00:00

Instead of storing strings that never change later under acpi_device_class(device) and using them for generating netlink messages, use pointers to string literals with the same content. This also allows the clearing of the acpi_device_class(device) area during driver removal and in the probe rollback path to be dropped. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/2070791.usQuhbGJ8B@rafael.j.wysocki

ACPI: button: Clean up adding and removing lid procfs interface

2026-06-02T19:07:09+00:00

The procfs interface is only used with lid devices which only becomes clear after looking into the function bodies of acpi_button_add_fs() and acpi_button_remove_fs(). Moreover, the only error code returned by the former of these functions is -ENODEV, so the ret local variable in it is redundant, and the return type of the latter one can be changed to void. Accordingly, rename these functions to acpi_button_add_fs() and acpi_button_remove_fs(), respectively, move the button->type checks against ACPI_BUTTON_TYPE_LID from them to their callers, and make code simplifications as per the above. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/1869050.VLH7GnMWUR@rafael.j.wysocki

ACPI: button: Merge two switch () statements in acpi_button_probe()

2026-06-02T19:07:09+00:00

Two switch () statements in acpi_button_probe() operate on the same value and the statements between them can be reordered with respect to the second one, so merge them. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/3352815.5fSG56mABF@rafael.j.wysocki

ACPI: button: Drop redundant variable from acpi_button_probe()

2026-06-02T19:07:09+00:00

Local char pointer called "name" in acpi_button_probe() is redundant because its value can be assigned directly to input->name and the latter can be used in the only other place where "name" is read, so get rid of it. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/3706239.iIbC2pHGDl@rafael.j.wysocki

ACPI: button: Rework device verification during probe

2026-06-02T19:06:35+00:00

Instead of manually comparing the primary ID of the device (retuned by _HID) with each of the device IDs supported by the driver, use acpi_match_acpi_device() (which includes the ACPI companion device pointer check against NULL) and store the ACPI button type as driver_data in button_device_ids[], which allows a multi-branch conditional statement to be replaced with a switch () one. However, to continue preventing successful probing of devices that only have one of the supported device IDs in their _CID lists, compare the matched device ID with the primary ID of the device and return an error if they don't match. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/7960518.EvYhyI6sBW@rafael.j.wysocki [ rjw: Fixed button memory leak on probe failure ] Signed-off-by: Rafael J. Wysocki

ACPI: button: Use local pointer to platform device dev field in probe

2026-06-01T17:17:49+00:00

To avoid dereferencing pdev to get to the target platform device's dev field in multiple places in acpi_button_probe(), use a local pointer to that field. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/2049596.PYKUYFuaPT@rafael.j.wysocki

ACPI: button: Eliminate redundant conditional statement

2026-06-01T17:17:49+00:00

Simplify do_update initialization in acpi_lid_notify_state() by assigning the value of the condition it depends on directly to it. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/10868292.nUPlyArG6x@rafael.j.wysocki

ACPI: button: Change return type of two functions to void

2026-06-01T17:17:49+00:00

The return value of acpi_lid_notify_state() is always 0, so change its return type to void. Moreover, the return value of the only caller of that function, acpi_lid_update_state(), is never used, so change its return type to void either. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/3429748.44csPzL39Z@rafael.j.wysocki