summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/tiny-power-button.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/acpi/tiny-power-button.c')
-rw-r--r--drivers/acpi/tiny-power-button.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/drivers/acpi/tiny-power-button.c b/drivers/acpi/tiny-power-button.c
new file mode 100644
index 0000000000..6353be6fec
--- /dev/null
+++ b/drivers/acpi/tiny-power-button.c
@@ -0,0 +1,80 @@
+// 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 void acpi_tiny_power_button_notify(acpi_handle handle, u32 event, void *data)
+{
+ kill_cad_pid(power_signal, 1);
+}
+
+static void acpi_tiny_power_button_notify_run(void *not_used)
+{
+ acpi_tiny_power_button_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, NULL);
+}
+
+static u32 acpi_tiny_power_button_event(void *not_used)
+{
+ acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_tiny_power_button_notify_run, NULL);
+ return ACPI_INTERRUPT_HANDLED;
+}
+
+static int acpi_tiny_power_button_add(struct acpi_device *device)
+{
+ acpi_status status;
+
+ if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON) {
+ status = acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
+ acpi_tiny_power_button_event,
+ NULL);
+ } else {
+ status = acpi_install_notify_handler(device->handle,
+ ACPI_DEVICE_NOTIFY,
+ acpi_tiny_power_button_notify,
+ NULL);
+ }
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ return 0;
+}
+
+static void acpi_tiny_power_button_remove(struct acpi_device *device)
+{
+ if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON) {
+ acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
+ acpi_tiny_power_button_event);
+ } else {
+ acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
+ acpi_tiny_power_button_notify);
+ }
+ acpi_os_wait_events_complete();
+}
+
+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_tiny_power_button_add,
+ .remove = acpi_tiny_power_button_remove,
+ },
+};
+
+module_acpi_driver(acpi_tiny_power_button_driver);