https://github.com/torvalds/linux
Tip revision: 6a8b55ed4056ea5559ebe4f6a4b247f627870d4c authored by Linus Torvalds on 26 April 2020, 20:51:02 UTC
Linux 5.7-rc3
Linux 5.7-rc3
Tip revision: 6a8b55e
intel-vbtn.c
// SPDX-License-Identifier: GPL-2.0+
/*
* Intel Virtual Button driver for Windows 8.1+
*
* Copyright (C) 2016 AceLan Kao <acelan.kao@canonical.com>
* Copyright (C) 2016 Alex Hung <alex.hung@canonical.com>
*/
#include <linux/acpi.h>
#include <linux/dmi.h>
#include <linux/input.h>
#include <linux/input/sparse-keymap.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/suspend.h>
/* When NOT in tablet mode, VGBS returns with the flag 0x40 */
#define TABLET_MODE_FLAG 0x40
#define DOCK_MODE_FLAG 0x80
MODULE_LICENSE("GPL");
MODULE_AUTHOR("AceLan Kao");
static const struct acpi_device_id intel_vbtn_ids[] = {
{"INT33D6", 0},
{"", 0},
};
MODULE_DEVICE_TABLE(acpi, intel_vbtn_ids);
/* In theory, these are HID usages. */
static const struct key_entry intel_vbtn_keymap[] = {
{ KE_KEY, 0xC0, { KEY_POWER } }, /* power key press */
{ KE_IGNORE, 0xC1, { KEY_POWER } }, /* power key release */
{ KE_KEY, 0xC2, { KEY_LEFTMETA } }, /* 'Windows' key press */
{ KE_KEY, 0xC3, { KEY_LEFTMETA } }, /* 'Windows' key release */
{ KE_KEY, 0xC4, { KEY_VOLUMEUP } }, /* volume-up key press */
{ KE_IGNORE, 0xC5, { KEY_VOLUMEUP } }, /* volume-up key release */
{ KE_KEY, 0xC6, { KEY_VOLUMEDOWN } }, /* volume-down key press */
{ KE_IGNORE, 0xC7, { KEY_VOLUMEDOWN } }, /* volume-down key release */
{ KE_KEY, 0xC8, { KEY_ROTATE_LOCK_TOGGLE } }, /* rotate-lock key press */
{ KE_KEY, 0xC9, { KEY_ROTATE_LOCK_TOGGLE } }, /* rotate-lock key release */
{ KE_SW, 0xCA, { .sw = { SW_DOCK, 1 } } }, /* Docked */
{ KE_SW, 0xCB, { .sw = { SW_DOCK, 0 } } }, /* Undocked */
{ KE_SW, 0xCC, { .sw = { SW_TABLET_MODE, 1 } } }, /* Tablet */
{ KE_SW, 0xCD, { .sw = { SW_TABLET_MODE, 0 } } }, /* Laptop */
{ KE_END },
};
struct intel_vbtn_priv {
struct input_dev *input_dev;
bool wakeup_mode;
};
static int intel_vbtn_input_setup(struct platform_device *device)
{
struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
int ret;
priv->input_dev = devm_input_allocate_device(&device->dev);
if (!priv->input_dev)
return -ENOMEM;
ret = sparse_keymap_setup(priv->input_dev, intel_vbtn_keymap, NULL);
if (ret)
return ret;
priv->input_dev->dev.parent = &device->dev;
priv->input_dev->name = "Intel Virtual Button driver";
priv->input_dev->id.bustype = BUS_HOST;
return input_register_device(priv->input_dev);
}
static void notify_handler(acpi_handle handle, u32 event, void *context)
{
struct platform_device *device = context;
struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
unsigned int val = !(event & 1); /* Even=press, Odd=release */
const struct key_entry *ke, *ke_rel;
bool autorelease;
if (priv->wakeup_mode) {
ke = sparse_keymap_entry_from_scancode(priv->input_dev, event);
if (ke) {
pm_wakeup_hard_event(&device->dev);
/*
* Switch events like tablet mode will wake the device
* and report the new switch position to the input
* subsystem.
*/
if (ke->type == KE_SW)
sparse_keymap_report_event(priv->input_dev,
event,
val,
0);
return;
}
goto out_unknown;
}
/*
* Even press events are autorelease if there is no corresponding odd
* release event, or if the odd event is KE_IGNORE.
*/
ke_rel = sparse_keymap_entry_from_scancode(priv->input_dev, event | 1);
autorelease = val && (!ke_rel || ke_rel->type == KE_IGNORE);
if (sparse_keymap_report_event(priv->input_dev, event, val, autorelease))
return;
out_unknown:
dev_dbg(&device->dev, "unknown event index 0x%x\n", event);
}
static void detect_tablet_mode(struct platform_device *device)
{
const char *chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE);
struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
acpi_handle handle = ACPI_HANDLE(&device->dev);
struct acpi_buffer vgbs_output = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
acpi_status status;
int m;
if (!(chassis_type && strcmp(chassis_type, "31") == 0))
goto out;
status = acpi_evaluate_object(handle, "VGBS", NULL, &vgbs_output);
if (ACPI_FAILURE(status))
goto out;
obj = vgbs_output.pointer;
if (!(obj && obj->type == ACPI_TYPE_INTEGER))
goto out;
m = !(obj->integer.value & TABLET_MODE_FLAG);
input_report_switch(priv->input_dev, SW_TABLET_MODE, m);
m = (obj->integer.value & DOCK_MODE_FLAG) ? 1 : 0;
input_report_switch(priv->input_dev, SW_DOCK, m);
out:
kfree(vgbs_output.pointer);
}
static int intel_vbtn_probe(struct platform_device *device)
{
acpi_handle handle = ACPI_HANDLE(&device->dev);
struct intel_vbtn_priv *priv;
acpi_status status;
int err;
status = acpi_evaluate_object(handle, "VBDL", NULL, NULL);
if (ACPI_FAILURE(status)) {
dev_warn(&device->dev, "failed to read Intel Virtual Button driver\n");
return -ENODEV;
}
priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
dev_set_drvdata(&device->dev, priv);
err = intel_vbtn_input_setup(device);
if (err) {
pr_err("Failed to setup Intel Virtual Button\n");
return err;
}
detect_tablet_mode(device);
status = acpi_install_notify_handler(handle,
ACPI_DEVICE_NOTIFY,
notify_handler,
device);
if (ACPI_FAILURE(status))
return -EBUSY;
device_init_wakeup(&device->dev, true);
/*
* In order for system wakeup to work, the EC GPE has to be marked as
* a wakeup one, so do that here (this setting will persist, but it has
* no effect until the wakeup mask is set for the EC GPE).
*/
acpi_ec_mark_gpe_for_wake();
return 0;
}
static int intel_vbtn_remove(struct platform_device *device)
{
acpi_handle handle = ACPI_HANDLE(&device->dev);
device_init_wakeup(&device->dev, false);
acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);
/*
* Even if we failed to shut off the event stream, we can still
* safely detach from the device.
*/
return 0;
}
static int intel_vbtn_pm_prepare(struct device *dev)
{
if (device_may_wakeup(dev)) {
struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
priv->wakeup_mode = true;
}
return 0;
}
static void intel_vbtn_pm_complete(struct device *dev)
{
struct intel_vbtn_priv *priv = dev_get_drvdata(dev);
priv->wakeup_mode = false;
}
static int intel_vbtn_pm_resume(struct device *dev)
{
intel_vbtn_pm_complete(dev);
return 0;
}
static const struct dev_pm_ops intel_vbtn_pm_ops = {
.prepare = intel_vbtn_pm_prepare,
.complete = intel_vbtn_pm_complete,
.resume = intel_vbtn_pm_resume,
.restore = intel_vbtn_pm_resume,
.thaw = intel_vbtn_pm_resume,
};
static struct platform_driver intel_vbtn_pl_driver = {
.driver = {
.name = "intel-vbtn",
.acpi_match_table = intel_vbtn_ids,
.pm = &intel_vbtn_pm_ops,
},
.probe = intel_vbtn_probe,
.remove = intel_vbtn_remove,
};
static acpi_status __init
check_acpi_dev(acpi_handle handle, u32 lvl, void *context, void **rv)
{
const struct acpi_device_id *ids = context;
struct acpi_device *dev;
if (acpi_bus_get_device(handle, &dev) != 0)
return AE_OK;
if (acpi_match_device_ids(dev, ids) == 0)
if (acpi_create_platform_device(dev, NULL))
dev_info(&dev->dev,
"intel-vbtn: created platform device\n");
return AE_OK;
}
static int __init intel_vbtn_init(void)
{
acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
ACPI_UINT32_MAX, check_acpi_dev, NULL,
(void *)intel_vbtn_ids, NULL);
return platform_driver_register(&intel_vbtn_pl_driver);
}
module_init(intel_vbtn_init);
static void __exit intel_vbtn_exit(void)
{
platform_driver_unregister(&intel_vbtn_pl_driver);
}
module_exit(intel_vbtn_exit);