1 files changed, 329 insertions, 164 deletions

diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c
index ef1856b15488..3c6dd9b4ba0a 100644
--- a/drivers/acpi/button.c
+++ b/drivers/acpi/button.c
@@ -1,26 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *  button.c - ACPI Button Driver
  *
  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
- *
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- *
- *  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.
- *
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  */
 
 #define pr_fmt(fmt) "ACPI: button: " fmt
 
+#include <linux/compiler.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
@@ -30,37 +18,40 @@
 #include <linux/input.h>
 #include <linux/slab.h>
 #include <linux/acpi.h>
+#include <linux/dmi.h>
 #include <acpi/button.h>
 
-#define PREFIX "ACPI: "
-
 #define ACPI_BUTTON_CLASS		"button"
-#define ACPI_BUTTON_FILE_INFO		"info"
 #define ACPI_BUTTON_FILE_STATE		"state"
 #define ACPI_BUTTON_TYPE_UNKNOWN	0x00
+#define ACPI_BUTTON_NOTIFY_WAKE		0x02
 #define ACPI_BUTTON_NOTIFY_STATUS	0x80
 
 #define ACPI_BUTTON_SUBCLASS_POWER	"power"
-#define ACPI_BUTTON_HID_POWER		"PNP0C0C"
 #define ACPI_BUTTON_DEVICE_NAME_POWER	"Power Button"
 #define ACPI_BUTTON_TYPE_POWER		0x01
 
 #define ACPI_BUTTON_SUBCLASS_SLEEP	"sleep"
-#define ACPI_BUTTON_HID_SLEEP		"PNP0C0E"
 #define ACPI_BUTTON_DEVICE_NAME_SLEEP	"Sleep Button"
 #define ACPI_BUTTON_TYPE_SLEEP		0x03
 
 #define ACPI_BUTTON_SUBCLASS_LID	"lid"
-#define ACPI_BUTTON_HID_LID		"PNP0C0D"
 #define ACPI_BUTTON_DEVICE_NAME_LID	"Lid Switch"
 #define ACPI_BUTTON_TYPE_LID		0x05
 
-#define ACPI_BUTTON_LID_INIT_IGNORE	0x00
-#define ACPI_BUTTON_LID_INIT_OPEN	0x01
-#define ACPI_BUTTON_LID_INIT_METHOD	0x02
+enum {
+	ACPI_BUTTON_LID_INIT_IGNORE,
+	ACPI_BUTTON_LID_INIT_OPEN,
+	ACPI_BUTTON_LID_INIT_METHOD,
+	ACPI_BUTTON_LID_INIT_DISABLED,
+};
 
-#define _COMPONENT		ACPI_BUTTON_COMPONENT
-ACPI_MODULE_NAME("button");
+static const char * const lid_init_state_str[] = {
+	[ACPI_BUTTON_LID_INIT_IGNORE]		= "ignore",
+	[ACPI_BUTTON_LID_INIT_OPEN]		= "open",
+	[ACPI_BUTTON_LID_INIT_METHOD]		= "method",
+	[ACPI_BUTTON_LID_INIT_DISABLED]		= "disabled",
+};
 
 MODULE_AUTHOR("Paul Diefenbaugh");
 MODULE_DESCRIPTION("ACPI Button Driver");
@@ -76,9 +67,86 @@ static const struct acpi_device_id button_device_ids[] = {
 };
 MODULE_DEVICE_TABLE(acpi, button_device_ids);
 
+/* Please keep this list sorted alphabetically by vendor and model */
+static const struct dmi_system_id dmi_lid_quirks[] = {
+	{
+		/* GP-electronic T701, _LID method points to a floating GPIO */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Insyde"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "T701"),
+			DMI_MATCH(DMI_BIOS_VERSION, "BYT70A.YNCHENG.WIN.007"),
+		},
+		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_DISABLED,
+	},
+	{
+		/* Nextbook Ares 8A tablet, _LID device always reports lid closed */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Insyde"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "CherryTrail"),
+			DMI_MATCH(DMI_BIOS_VERSION, "M882"),
+		},
+		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_DISABLED,
+	},
+	{
+		/*
+		 * Lenovo Yoga 9 14ITL5, initial notification of the LID device
+		 * never happens.
+		 */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "82BG"),
+		},
+		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
+	},
+	{
+		/*
+		 * Medion Akoya E2215T, notification of the LID device only
+		 * happens on close, not on open and _LID always returns closed.
+		 */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "MEDION"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "E2215T"),
+		},
+		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
+	},
+	{
+		/*
+		 * Medion Akoya E2228T, notification of the LID device only
+		 * happens on close, not on open and _LID always returns closed.
+		 */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "MEDION"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "E2228T"),
+		},
+		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
+	},
+	{
+		/*
+		 * Razer Blade Stealth 13 late 2019, notification of the LID device
+		 * only happens on close, not on open and _LID always returns closed.
+		 */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Razer"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Razer Blade Stealth 13 Late 2019"),
+		},
+		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
+	},
+	{
+		/*
+		 * Samsung galaxybook2 ,initial _LID device notification returns
+		 * lid closed.
+		 */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "750XED"),
+		},
+		.driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN,
+	},
+	{}
+};
+
 static int acpi_button_add(struct acpi_device *device);
-static int acpi_button_remove(struct acpi_device *device);
-static void acpi_button_notify(struct acpi_device *device, u32 event);
+static void acpi_button_remove(struct acpi_device *device);
 
 #ifdef CONFIG_PM_SLEEP
 static int acpi_button_suspend(struct device *dev);
@@ -96,7 +164,6 @@ static struct acpi_driver acpi_button_driver = {
 	.ops = {
 		.add = acpi_button_add,
 		.remove = acpi_button_remove,
-		.notify = acpi_button_notify,
 	},
 	.drv.pm = &acpi_button_pm,
 };
@@ -109,20 +176,17 @@ struct acpi_button {
 	int last_state;
 	ktime_t last_time;
 	bool suspended;
+	bool lid_state_initialized;
 };
 
-static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier);
 static struct acpi_device *lid_device;
-static u8 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
+static long lid_init_state = -1;
 
 static unsigned long lid_report_interval __read_mostly = 500;
 module_param(lid_report_interval, ulong, 0644);
 MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events");
 
-/* --------------------------------------------------------------------------
-                              FS Interface (/proc)
-   -------------------------------------------------------------------------- */
-
+/* FS Interface (/proc) */
 static struct proc_dir_entry *acpi_button_dir;
 static struct proc_dir_entry *acpi_lid_dir;
 
@@ -141,7 +205,6 @@ static int acpi_lid_evaluate_state(struct acpi_device *device)
 static int acpi_lid_notify_state(struct acpi_device *device, int state)
 {
 	struct acpi_button *button = acpi_driver_data(device);
-	int ret;
 	ktime_t next_report;
 	bool do_update;
 
@@ -210,30 +273,19 @@ static int acpi_lid_notify_state(struct acpi_device *device, int state)
 	}
 	/* Send the platform triggered reliable event */
 	if (do_update) {
+		acpi_handle_debug(device->handle, "ACPI LID %s\n",
+				  state ? "open" : "closed");
 		input_report_switch(button->input, SW_LID, !state);
 		input_sync(button->input);
 		button->last_state = !!state;
 		button->last_time = ktime_get();
 	}
 
-	if (state)
-		acpi_pm_wakeup_event(&device->dev);
-
-	ret = blocking_notifier_call_chain(&acpi_lid_notifier, state, device);
-	if (ret == NOTIFY_DONE)
-		ret = blocking_notifier_call_chain(&acpi_lid_notifier, state,
-						   device);
-	if (ret == NOTIFY_DONE || ret == NOTIFY_OK) {
-		/*
-		 * It is also regarded as success if the notifier_chain
-		 * returns NOTIFY_OK or NOTIFY_DONE.
-		 */
-		ret = 0;
-	}
-	return ret;
+	return 0;
 }
 
-static int acpi_button_state_seq_show(struct seq_file *seq, void *offset)
+static int __maybe_unused acpi_button_state_seq_show(struct seq_file *seq,
+						     void *offset)
 {
 	struct acpi_device *device = seq->private;
 	int state;
@@ -244,19 +296,6 @@ static int acpi_button_state_seq_show(struct seq_file *seq, void *offset)
 	return 0;
 }
 
-static int acpi_button_state_open_fs(struct inode *inode, struct file *file)
-{
-	return single_open(file, acpi_button_state_seq_show, PDE_DATA(inode));
-}
-
-static const struct file_operations acpi_button_state_fops = {
-	.owner = THIS_MODULE,
-	.open = acpi_button_state_open_fs,
-	.read = seq_read,
-	.llseek = seq_lseek,
-	.release = single_release,
-};
-
 static int acpi_button_add_fs(struct acpi_device *device)
 {
 	struct acpi_button *button = acpi_driver_data(device);
@@ -268,7 +307,7 @@ static int acpi_button_add_fs(struct acpi_device *device)
 		return 0;
 
 	if (acpi_button_dir || acpi_lid_dir) {
-		printk(KERN_ERR PREFIX "More than one Lid device found!\n");
+		pr_info("More than one Lid device found!\n");
 		return -EEXIST;
 	}
 
@@ -292,9 +331,9 @@ static int acpi_button_add_fs(struct acpi_device *device)
 	}
 
 	/* create /proc/acpi/button/lid/LID/state */
-	entry = proc_create_data(ACPI_BUTTON_FILE_STATE,
-				 S_IRUGO, acpi_device_dir(device),
-				 &acpi_button_state_fops, device);
+	entry = proc_create_single_data(ACPI_BUTTON_FILE_STATE, S_IRUGO,
+			acpi_device_dir(device), acpi_button_state_seq_show,
+			device);
 	if (!entry) {
 		ret = -ENODEV;
 		goto remove_dev_dir;
@@ -336,21 +375,7 @@ static int acpi_button_remove_fs(struct acpi_device *device)
 	return 0;
 }
 
-/* --------------------------------------------------------------------------
-                                Driver Interface
-   -------------------------------------------------------------------------- */
-int acpi_lid_notifier_register(struct notifier_block *nb)
-{
-	return blocking_notifier_chain_register(&acpi_lid_notifier, nb);
-}
-EXPORT_SYMBOL(acpi_lid_notifier_register);
-
-int acpi_lid_notifier_unregister(struct notifier_block *nb)
-{
-	return blocking_notifier_chain_unregister(&acpi_lid_notifier, nb);
-}
-EXPORT_SYMBOL(acpi_lid_notifier_unregister);
-
+/* Driver Interface */
 int acpi_lid_open(void)
 {
 	if (!lid_device)
@@ -360,7 +385,8 @@ int acpi_lid_open(void)
 }
 EXPORT_SYMBOL(acpi_lid_open);
 
-static int acpi_lid_update_state(struct acpi_device *device)
+static int acpi_lid_update_state(struct acpi_device *device,
+				 bool signal_wakeup)
 {
 	int state;
 
@@ -368,62 +394,95 @@ static int acpi_lid_update_state(struct acpi_device *device)
 	if (state < 0)
 		return state;
 
+	if (state && signal_wakeup)
+		acpi_pm_wakeup_event(&device->dev);
+
 	return acpi_lid_notify_state(device, state);
 }
 
 static void acpi_lid_initialize_state(struct acpi_device *device)
 {
+	struct acpi_button *button = acpi_driver_data(device);
+
 	switch (lid_init_state) {
 	case ACPI_BUTTON_LID_INIT_OPEN:
 		(void)acpi_lid_notify_state(device, 1);
 		break;
 	case ACPI_BUTTON_LID_INIT_METHOD:
-		(void)acpi_lid_update_state(device);
+		(void)acpi_lid_update_state(device, false);
 		break;
 	case ACPI_BUTTON_LID_INIT_IGNORE:
 	default:
 		break;
 	}
+
+	button->lid_state_initialized = true;
 }
 
-static void acpi_button_notify(struct acpi_device *device, u32 event)
+static void acpi_lid_notify(acpi_handle handle, u32 event, void *data)
 {
-	struct acpi_button *button = acpi_driver_data(device);
+	struct acpi_device *device = data;
+	struct acpi_button *button;
+
+	if (event != ACPI_BUTTON_NOTIFY_STATUS) {
+		acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
+				  event);
+		return;
+	}
+
+	button = acpi_driver_data(device);
+	if (!button->lid_state_initialized)
+		return;
+
+	acpi_lid_update_state(device, true);
+}
+
+static void acpi_button_notify(acpi_handle handle, u32 event, void *data)
+{
+	struct acpi_device *device = data;
+	struct acpi_button *button;
 	struct input_dev *input;
+	int keycode;
 
 	switch (event) {
-	case ACPI_FIXED_HARDWARE_EVENT:
-		event = ACPI_BUTTON_NOTIFY_STATUS;
-		/* fall through */
 	case ACPI_BUTTON_NOTIFY_STATUS:
-		input = button->input;
-		if (button->type == ACPI_BUTTON_TYPE_LID) {
-			acpi_lid_update_state(device);
-		} else {
-			int keycode;
-
-			acpi_pm_wakeup_event(&device->dev);
-			if (button->suspended)
-				break;
-
-			keycode = test_bit(KEY_SLEEP, input->keybit) ?
-						KEY_SLEEP : KEY_POWER;
-			input_report_key(input, keycode, 1);
-			input_sync(input);
-			input_report_key(input, keycode, 0);
-			input_sync(input);
-
-			acpi_bus_generate_netlink_event(
-					device->pnp.device_class,
-					dev_name(&device->dev),
-					event, ++button->pushed);
-		}
 		break;
-	default:
-		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-				  "Unsupported event [0x%x]\n", event));
+	case ACPI_BUTTON_NOTIFY_WAKE:
 		break;
+	default:
+		acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
+				  event);
+		return;
 	}
+
+	acpi_pm_wakeup_event(&device->dev);
+
+	button = acpi_driver_data(device);
+	if (button->suspended || event == ACPI_BUTTON_NOTIFY_WAKE)
+		return;
+
+	input = button->input;
+	keycode = test_bit(KEY_SLEEP, input->keybit) ? KEY_SLEEP : KEY_POWER;
+
+	input_report_key(input, keycode, 1);
+	input_sync(input);
+	input_report_key(input, keycode, 0);
+	input_sync(input);
+
+	acpi_bus_generate_netlink_event(device->pnp.device_class,
+					dev_name(&device->dev),
+					event, ++button->pushed);
+}
+
+static void acpi_button_notify_run(void *data)
+{
+	acpi_button_notify(NULL, ACPI_BUTTON_NOTIFY_STATUS, data);
+}
+
+static u32 acpi_button_event(void *data)
+{
+	acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_button_notify_run, data);
+	return ACPI_INTERRUPT_HANDLED;
 }
 
 #ifdef CONFIG_PM_SLEEP
@@ -438,23 +497,53 @@ static int acpi_button_suspend(struct device *dev)
 
 static int acpi_button_resume(struct device *dev)
 {
+	struct input_dev *input;
 	struct acpi_device *device = to_acpi_device(dev);
 	struct acpi_button *button = acpi_driver_data(device);
 
 	button->suspended = false;
-	if (button->type == ACPI_BUTTON_TYPE_LID)
+	if (button->type == ACPI_BUTTON_TYPE_LID) {
+		button->last_state = !!acpi_lid_evaluate_state(device);
+		button->last_time = ktime_get();
 		acpi_lid_initialize_state(device);
+	}
+
+	if (button->type == ACPI_BUTTON_TYPE_POWER) {
+		input = button->input;
+		input_report_key(input, KEY_WAKEUP, 1);
+		input_sync(input);
+		input_report_key(input, KEY_WAKEUP, 0);
+		input_sync(input);
+	}
 	return 0;
 }
 #endif
 
+static int acpi_lid_input_open(struct input_dev *input)
+{
+	struct acpi_device *device = input_get_drvdata(input);
+	struct acpi_button *button = acpi_driver_data(device);
+
+	button->last_state = !!acpi_lid_evaluate_state(device);
+	button->last_time = ktime_get();
+	acpi_lid_initialize_state(device);
+
+	return 0;
+}
+
 static int acpi_button_add(struct acpi_device *device)
 {
+	acpi_notify_handler handler;
 	struct acpi_button *button;
 	struct input_dev *input;
 	const char *hid = acpi_device_hid(device);
+	acpi_status status;
 	char *name, *class;
-	int error;
+	int error = 0;
+
+	if (!strcmp(hid, ACPI_BUTTON_HID_LID) &&
+	     lid_init_state == ACPI_BUTTON_LID_INIT_DISABLED)
+		return -ENODEV;
 
 	button = kzalloc(sizeof(struct acpi_button), GFP_KERNEL);
 	if (!button)
@@ -474,31 +563,36 @@ static int acpi_button_add(struct acpi_device *device)
 	if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
 	    !strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
 		button->type = ACPI_BUTTON_TYPE_POWER;
-		strcpy(name, ACPI_BUTTON_DEVICE_NAME_POWER);
+		handler = acpi_button_notify;
+		strscpy(name, ACPI_BUTTON_DEVICE_NAME_POWER, MAX_ACPI_DEVICE_NAME_LEN);
 		sprintf(class, "%s/%s",
 			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
 	} else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
 		   !strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
 		button->type = ACPI_BUTTON_TYPE_SLEEP;
-		strcpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP);
+		handler = acpi_button_notify;
+		strscpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP, MAX_ACPI_DEVICE_NAME_LEN);
 		sprintf(class, "%s/%s",
 			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
 	} else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
 		button->type = ACPI_BUTTON_TYPE_LID;
-		strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID);
+		handler = acpi_lid_notify;
+		strscpy(name, ACPI_BUTTON_DEVICE_NAME_LID, MAX_ACPI_DEVICE_NAME_LEN);
 		sprintf(class, "%s/%s",
 			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
-		button->last_state = !!acpi_lid_evaluate_state(device);
-		button->last_time = ktime_get();
+		input->open = acpi_lid_input_open;
 	} else {
-		printk(KERN_ERR PREFIX "Unsupported hid [%s]\n", hid);
+		pr_info("Unsupported hid [%s]\n", hid);
 		error = -ENODEV;
-		goto err_free_input;
 	}
 
-	error = acpi_button_add_fs(device);
-	if (error)
-		goto err_free_input;
+	if (!error)
+		error = acpi_button_add_fs(device);
+
+	if (error) {
+		input_free_device(input);
+		goto err_free_button;
+	}
 
 	snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);
 
@@ -511,6 +605,7 @@ static int acpi_button_add(struct acpi_device *device)
 	switch (button->type) {
 	case ACPI_BUTTON_TYPE_POWER:
 		input_set_capability(input, EV_KEY, KEY_POWER);
+		input_set_capability(input, EV_KEY, KEY_WAKEUP);
 		break;
 
 	case ACPI_BUTTON_TYPE_SLEEP:
@@ -522,11 +617,36 @@ static int acpi_button_add(struct acpi_device *device)
 		break;
 	}
 
+	input_set_drvdata(input, device);
 	error = input_register_device(input);
-	if (error)
+	if (error) {
+		input_free_device(input);
 		goto err_remove_fs;
+	}
+
+	switch (device->device_type) {
+	case ACPI_BUS_TYPE_POWER_BUTTON:
+		status = acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
+							  acpi_button_event,
+							  device);
+		break;
+	case ACPI_BUS_TYPE_SLEEP_BUTTON:
+		status = acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
+							  acpi_button_event,
+							  device);
+		break;
+	default:
+		status = acpi_install_notify_handler(device->handle,
+						     ACPI_ALL_NOTIFY, handler,
+						     device);
+		break;
+	}
+	if (ACPI_FAILURE(status)) {
+		error = -ENODEV;
+		goto err_input_unregister;
+	}
+
 	if (button->type == ACPI_BUTTON_TYPE_LID) {
-		acpi_lid_initialize_state(device);
 		/*
 		 * This assumes there's only one lid device, or if there are
 		 * more we only care about the last one...
@@ -535,59 +655,72 @@ static int acpi_button_add(struct acpi_device *device)
 	}
 
 	device_init_wakeup(&device->dev, true);
-	printk(KERN_INFO PREFIX "%s [%s]\n", name, acpi_device_bid(device));
+	pr_info("%s [%s]\n", name, acpi_device_bid(device));
 	return 0;
 
- err_remove_fs:
+err_input_unregister:
+	input_unregister_device(input);
+err_remove_fs:
 	acpi_button_remove_fs(device);
- err_free_input:
-	input_free_device(input);
- err_free_button:
+err_free_button:
 	kfree(button);
 	return error;
 }
 
-static int acpi_button_remove(struct acpi_device *device)
+static void acpi_button_remove(struct acpi_device *device)
 {
 	struct acpi_button *button = acpi_driver_data(device);
 
+	switch (device->device_type) {
+	case ACPI_BUS_TYPE_POWER_BUTTON:
+		acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
+						acpi_button_event);
+		break;
+	case ACPI_BUS_TYPE_SLEEP_BUTTON:
+		acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
+						acpi_button_event);
+		break;
+	default:
+		acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
+					   button->type == ACPI_BUTTON_TYPE_LID ?
+						acpi_lid_notify :
+						acpi_button_notify);
+		break;
+	}
+	acpi_os_wait_events_complete();
+
 	acpi_button_remove_fs(device);
 	input_unregister_device(button->input);
 	kfree(button);
-	return 0;
 }
 
-static int param_set_lid_init_state(const char *val, struct kernel_param *kp)
+static int param_set_lid_init_state(const char *val,
+				    const struct kernel_param *kp)
 {
-	int result = 0;
-
-	if (!strncmp(val, "open", sizeof("open") - 1)) {
-		lid_init_state = ACPI_BUTTON_LID_INIT_OPEN;
-		pr_info("Notify initial lid state as open\n");
-	} else if (!strncmp(val, "method", sizeof("method") - 1)) {
-		lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
-		pr_info("Notify initial lid state with _LID return value\n");
-	} else if (!strncmp(val, "ignore", sizeof("ignore") - 1)) {
-		lid_init_state = ACPI_BUTTON_LID_INIT_IGNORE;
-		pr_info("Do not notify initial lid state\n");
-	} else
-		result = -EINVAL;
-	return result;
+	int i;
+
+	i = sysfs_match_string(lid_init_state_str, val);
+	if (i < 0)
+		return i;
+
+	lid_init_state = i;
+	pr_info("Initial lid state set to '%s'\n", lid_init_state_str[i]);
+	return 0;
 }
 
-static int param_get_lid_init_state(char *buffer, struct kernel_param *kp)
+static int param_get_lid_init_state(char *buf, const struct kernel_param *kp)
 {
-	switch (lid_init_state) {
-	case ACPI_BUTTON_LID_INIT_OPEN:
-		return sprintf(buffer, "open");
-	case ACPI_BUTTON_LID_INIT_METHOD:
-		return sprintf(buffer, "method");
-	case ACPI_BUTTON_LID_INIT_IGNORE:
-		return sprintf(buffer, "ignore");
-	default:
-		return sprintf(buffer, "invalid");
-	}
-	return 0;
+	int i, c = 0;
+
+	for (i = 0; i < ARRAY_SIZE(lid_init_state_str); i++)
+		if (i == lid_init_state)
+			c += sprintf(buf + c, "[%s] ", lid_init_state_str[i]);
+		else
+			c += sprintf(buf + c, "%s ", lid_init_state_str[i]);
+
+	buf[c - 1] = '\n'; /* Replace the final space with a newline */
+
+	return c;
 }
 
 module_param_call(lid_init_state,
@@ -595,4 +728,36 @@ module_param_call(lid_init_state,
 		  NULL, 0644);
 MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
 
-module_acpi_driver(acpi_button_driver);
+static int acpi_button_register_driver(struct acpi_driver *driver)
+{
+	const struct dmi_system_id *dmi_id;
+
+	if (lid_init_state == -1) {
+		dmi_id = dmi_first_match(dmi_lid_quirks);
+		if (dmi_id)
+			lid_init_state = (long)dmi_id->driver_data;
+		else
+			lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
+	}
+
+	/*
+	 * Modules such as nouveau.ko and i915.ko have a link time dependency
+	 * on acpi_lid_open(), and would therefore not be loadable on ACPI
+	 * capable kernels booted in non-ACPI mode if the return value of
+	 * acpi_bus_register_driver() is returned from here with ACPI disabled
+	 * when this driver is built as a module.
+	 */
+	if (acpi_disabled)
+		return 0;
+
+	return acpi_bus_register_driver(driver);
+}
+
+static void acpi_button_unregister_driver(struct acpi_driver *driver)
+{
+	if (!acpi_disabled)
+		acpi_bus_unregister_driver(driver);
+}
+
+module_driver(acpi_button_driver, acpi_button_register_driver,
+	       acpi_button_unregister_driver);