--- /dev/null
+/*
+ * WMI hotkeys support for Dell All-In-One series
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/input.h>
+#include <linux/input/sparse-keymap.h>
+#include <acpi/acpi_drivers.h>
+#include <linux/acpi.h>
+#include <linux/string.h>
+
+MODULE_DESCRIPTION("WMI hotkeys driver for Dell All-In-One series");
+MODULE_LICENSE("GPL");
+
+#define EVENT_GUID1 "284A0E6B-380E-472A-921F-E52786257FB4"
+#define EVENT_GUID2 "02314822-307C-4F66-BF0E-48AEAEB26CC8"
+
+static const char *dell_wmi_aio_guids[] = {
+ EVENT_GUID1,
+ EVENT_GUID2,
+ NULL
+};
+
+MODULE_ALIAS("wmi:"EVENT_GUID1);
+MODULE_ALIAS("wmi:"EVENT_GUID2);
+
+static const struct key_entry dell_wmi_aio_keymap[] = {
+ { KE_KEY, 0xc0, { KEY_VOLUMEUP } },
+ { KE_KEY, 0xc1, { KEY_VOLUMEDOWN } },
+ { KE_END, 0 }
+};
+
+static struct input_dev *dell_wmi_aio_input_dev;
+
+static void dell_wmi_aio_notify(u32 value, void *context)
+{
+ struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
+ union acpi_object *obj;
+ acpi_status status;
+
+ status = wmi_get_event_data(value, &response);
+ if (status != AE_OK) {
+ pr_info("bad event status 0x%x\n", status);
+ return;
+ }
+
+ obj = (union acpi_object *)response.pointer;
+ if (obj) {
+ unsigned int scancode;
+
+ switch (obj->type) {
+ case ACPI_TYPE_INTEGER:
+ /* Most All-In-One correctly return integer scancode */
+ scancode = obj->integer.value;
+ sparse_keymap_report_event(dell_wmi_aio_input_dev,
+ scancode, 1, true);
+ break;
+ case ACPI_TYPE_BUFFER:
+ /* Broken machines return the scancode in a buffer */
+ if (obj->buffer.pointer && obj->buffer.length > 0) {
+ scancode = obj->buffer.pointer[0];
+ sparse_keymap_report_event(
+ dell_wmi_aio_input_dev,
+ scancode, 1, true);
+ }
+ break;
+ }
+ }
+ kfree(obj);
+}
+
+static int __init dell_wmi_aio_input_setup(void)
+{
+ int err;
+
+ dell_wmi_aio_input_dev = input_allocate_device();
+
+ if (!dell_wmi_aio_input_dev)
+ return -ENOMEM;
+
+ dell_wmi_aio_input_dev->name = "Dell AIO WMI hotkeys";
+ dell_wmi_aio_input_dev->phys = "wmi/input0";
+ dell_wmi_aio_input_dev->id.bustype = BUS_HOST;
+
+ err = sparse_keymap_setup(dell_wmi_aio_input_dev,
+ dell_wmi_aio_keymap, NULL);
+ if (err) {
+ pr_err("Unable to setup input device keymap\n");
+ goto err_free_dev;
+ }
+ err = input_register_device(dell_wmi_aio_input_dev);
+ if (err) {
+ pr_info("Unable to register input device\n");
+ goto err_free_keymap;
+ }
+ return 0;
+
+err_free_keymap:
+ sparse_keymap_free(dell_wmi_aio_input_dev);
+err_free_dev:
+ input_free_device(dell_wmi_aio_input_dev);
+ return err;
+}
+
+static const char *dell_wmi_aio_find(void)
+{
+ int i;
+
+ for (i = 0; dell_wmi_aio_guids[i] != NULL; i++)
+ if (wmi_has_guid(dell_wmi_aio_guids[i]))
+ return dell_wmi_aio_guids[i];
+
+ return NULL;
+}
+
+static int __init dell_wmi_aio_init(void)
+{
+ int err;
+ const char *guid;
+
+ guid = dell_wmi_aio_find();
+ if (!guid) {
+ pr_warning("No known WMI GUID found\n");
+ return -ENXIO;
+ }
+
+ err = dell_wmi_aio_input_setup();
+ if (err)
+ return err;
+
+ err = wmi_install_notify_handler(guid, dell_wmi_aio_notify, NULL);
+ if (err) {
+ pr_err("Unable to register notify handler - %d\n", err);
+ sparse_keymap_free(dell_wmi_aio_input_dev);
+ input_unregister_device(dell_wmi_aio_input_dev);
+ return err;
+ }
+
+ return 0;
+}
+
+static void __exit dell_wmi_aio_exit(void)
+{
+ const char *guid;
+
+ guid = dell_wmi_aio_find();
+ wmi_remove_notify_handler(guid);
+ sparse_keymap_free(dell_wmi_aio_input_dev);
+ input_unregister_device(dell_wmi_aio_input_dev);
+}
+
+module_init(dell_wmi_aio_init);
+module_exit(dell_wmi_aio_exit);