linux/drivers/acpi/tiny-power-button.c
Dawei Li 6c0eb5ba35 ACPI: make remove callback of ACPI driver void
For bus-based driver, device removal is implemented as:
1 device_remove()->
2   bus->remove()->
3     driver->remove()

Driver core needs no inform from callee(bus driver) about the
result of remove callback. In that case, commit fc7a6209d5
("bus: Make remove callback return void") forces bus_type::remove
be void-returned.

Now we have the situation that both 1 & 2 of calling chain are
void-returned, so it does not make much sense for 3(driver->remove)
to return non-void to its caller.

So the basic idea behind this change is making remove() callback of
any bus-based driver to be void-returned.

This change, for itself, is for device drivers based on acpi-bus.

Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Lee Jones <lee@kernel.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dawei Li <set_pte_at@outlook.com>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com>  # for drivers/platform/surface/*
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-11-23 19:11:22 +01:00

48 lines
1.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
#include <linux/module.h>
#include <linux/sched/signal.h>
#include <linux/acpi.h>
#include <acpi/button.h>
MODULE_AUTHOR("Josh Triplett");
MODULE_DESCRIPTION("ACPI Tiny Power Button Driver");
MODULE_LICENSE("GPL");
static int power_signal __read_mostly = CONFIG_ACPI_TINY_POWER_BUTTON_SIGNAL;
module_param(power_signal, int, 0644);
MODULE_PARM_DESC(power_signal, "Power button sends this signal to init");
static const struct acpi_device_id tiny_power_button_device_ids[] = {
{ ACPI_BUTTON_HID_POWER, 0 },
{ ACPI_BUTTON_HID_POWERF, 0 },
{ "", 0 },
};
MODULE_DEVICE_TABLE(acpi, tiny_power_button_device_ids);
static int acpi_noop_add(struct acpi_device *device)
{
return 0;
}
static void acpi_noop_remove(struct acpi_device *device)
{
}
static void acpi_tiny_power_button_notify(struct acpi_device *device, u32 event)
{
kill_cad_pid(power_signal, 1);
}
static struct acpi_driver acpi_tiny_power_button_driver = {
.name = "tiny-power-button",
.class = "tiny-power-button",
.ids = tiny_power_button_device_ids,
.ops = {
.add = acpi_noop_add,
.remove = acpi_noop_remove,
.notify = acpi_tiny_power_button_notify,
},
};
module_acpi_driver(acpi_tiny_power_button_driver);