Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 833 insertions, 0 deletions

diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c
new file mode 100644
index 000000000..cdbb1023a
--- /dev/null
+++ b/drivers/acpi/button.c
@@ -0,0 +1,833 @@
+// 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>
+ */
+
+#define pr_fmt(fmt) "ACPI: button: " fmt
+
+#include <linux/compiler.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/acpi.h>
+#include <linux/dmi.h>
+#include <linux/platform_device.h>
+#include <acpi/button.h>
+
+#define ACPI_BUTTON_CLASS		"button"
+#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_CLASS_POWER		"button/power"
+#define ACPI_BUTTON_DEVICE_NAME_POWER	"Power Button"
+#define ACPI_BUTTON_TYPE_POWER		0x01
+
+#define ACPI_BUTTON_CLASS_SLEEP		"button/sleep"
+#define ACPI_BUTTON_DEVICE_NAME_SLEEP	"Sleep Button"
+#define ACPI_BUTTON_TYPE_SLEEP		0x03
+
+#define ACPI_BUTTON_CLASS_LID		"button/lid"
+#define ACPI_BUTTON_SUBCLASS_LID	"lid"
+#define ACPI_BUTTON_DEVICE_NAME_LID	"Lid Switch"
+#define ACPI_BUTTON_TYPE_LID		0x05
+
+enum {
+	ACPI_BUTTON_LID_INIT_IGNORE,
+	ACPI_BUTTON_LID_INIT_OPEN,
+	ACPI_BUTTON_LID_INIT_METHOD,
+	ACPI_BUTTON_LID_INIT_DISABLED,
+};
+
+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");
+MODULE_LICENSE("GPL");
+
+static const struct acpi_device_id button_device_ids[] = {
+	{ACPI_BUTTON_HID_LID, ACPI_BUTTON_TYPE_LID},
+	{ACPI_BUTTON_HID_SLEEP, ACPI_BUTTON_TYPE_SLEEP},
+	{ACPI_BUTTON_HID_SLEEPF, ACPI_BUTTON_TYPE_SLEEP},
+	{ACPI_BUTTON_HID_POWER, ACPI_BUTTON_TYPE_POWER},
+	{ACPI_BUTTON_HID_POWERF, ACPI_BUTTON_TYPE_POWER},
+	{"", 0},
+};
+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,
+	},
+	{
+		/*
+		 * Razer Blade Pro 17 early 2020, notification of the LID device
+		 * only happens on close, not on open and _LID keeps returning closed.
+		 */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Razer"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Blade Pro 17 (Early 2020) - RZ09-0329"),
+		},
+		.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_probe(struct platform_device *pdev);
+static void acpi_button_remove(struct platform_device *pdev);
+
+#ifdef CONFIG_PM_SLEEP
+static int acpi_button_suspend(struct device *dev);
+static int acpi_button_resume(struct device *dev);
+#else
+#define acpi_button_suspend NULL
+#define acpi_button_resume NULL
+#endif
+static SIMPLE_DEV_PM_OPS(acpi_button_pm, acpi_button_suspend, acpi_button_resume);
+
+static struct platform_driver acpi_button_driver = {
+	.probe = acpi_button_probe,
+	.remove = acpi_button_remove,
+	.driver = {
+		.name = "acpi-button",
+		.acpi_match_table = button_device_ids,
+		.pm = &acpi_button_pm,
+	},
+};
+
+struct acpi_button {
+	struct acpi_device *adev;
+	struct device *dev;		/* physical button device */
+	unsigned int type;
+	struct input_dev *input;
+	const char *class;		/* for netlink messages */
+	char phys[32];			/* for input device */
+	unsigned long pushed;
+	bool last_state;
+	ktime_t last_time;
+	bool suspended;
+	bool lid_state_initialized;
+	bool gpe_enabled;
+};
+
+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) */
+static struct proc_dir_entry *acpi_button_dir;
+static struct proc_dir_entry *acpi_lid_dir;
+
+static int acpi_lid_evaluate_state(acpi_handle lid_handle)
+{
+	unsigned long long lid_state;
+	acpi_status status;
+
+	status = acpi_evaluate_integer(lid_handle, "_LID", NULL, &lid_state);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	return !!lid_state;
+}
+
+static void acpi_lid_notify_state(struct acpi_button *button, bool state)
+{
+	struct acpi_device *device = button->adev;
+	ktime_t next_report;
+	bool do_update;
+
+	/*
+	 * In lid_init_state=ignore mode, if user opens/closes lid
+	 * frequently with "open" missing, and "last_time" is also updated
+	 * frequently, "close" cannot be delivered to the userspace.
+	 * So "last_time" is only updated after a timeout or an actual
+	 * switch.
+	 */
+	do_update = lid_init_state != ACPI_BUTTON_LID_INIT_IGNORE ||
+			button->last_state != state;
+	next_report = ktime_add(button->last_time,
+				ms_to_ktime(lid_report_interval));
+	if (button->last_state == state &&
+	    ktime_after(ktime_get(), next_report)) {
+		/* Complain about the buggy firmware. */
+		pr_warn_once(FW_BUG "Unexpected lid state reported by firmware\n");
+
+		/*
+		 * Send the unreliable complement switch event:
+		 *
+		 * On most platforms, the lid device is reliable. However
+		 * there are exceptions:
+		 * 1. Platforms returning initial lid state as "close" by
+		 *    default after booting/resuming:
+		 *     https://bugzilla.kernel.org/show_bug.cgi?id=89211
+		 *     https://bugzilla.kernel.org/show_bug.cgi?id=106151
+		 * 2. Platforms never reporting "open" events:
+		 *     https://bugzilla.kernel.org/show_bug.cgi?id=106941
+		 * On these buggy platforms, the usage model of the ACPI
+		 * lid device actually is:
+		 * 1. The initial returning value of _LID may not be
+		 *    reliable.
+		 * 2. The open event may not be reliable.
+		 * 3. The close event is reliable.
+		 *
+		 * But SW_LID is typed as input switch event, the input
+		 * layer checks if the event is redundant. Hence if the
+		 * state is not switched, the userspace cannot see this
+		 * platform triggered reliable event. By inserting a
+		 * complement switch event, it then is guaranteed that the
+		 * platform triggered reliable one can always be seen by
+		 * the userspace.
+		 */
+		if (lid_init_state == ACPI_BUTTON_LID_INIT_IGNORE) {
+			do_update = true;
+			/*
+			 * Do generate complement switch event for "close"
+			 * as "close" is reliable and wrong "open" won't
+			 * trigger unexpected behaviors.
+			 * Do not generate complement switch event for
+			 * "open" as "open" is not reliable and wrong
+			 * "close" will trigger unexpected behaviors.
+			 */
+			if (!state) {
+				input_report_switch(button->input,
+						    SW_LID, state);
+				input_sync(button->input);
+			}
+		}
+	}
+	/* 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();
+	}
+}
+
+static int __maybe_unused acpi_button_state_seq_show(struct seq_file *seq,
+						     void *offset)
+{
+	struct acpi_button *button = seq->private;
+	int state;
+
+	state = acpi_lid_evaluate_state(button->adev->handle);
+	seq_printf(seq, "state:      %s\n",
+		   state < 0 ? "unsupported" : (state ? "open" : "closed"));
+	return 0;
+}
+
+static int acpi_lid_add_fs(struct acpi_button *button)
+{
+	struct acpi_device *device = button->adev;
+	struct proc_dir_entry *entry = NULL;
+
+	if (acpi_button_dir || acpi_lid_dir) {
+		pr_info("More than one Lid device found!\n");
+		return -EEXIST;
+	}
+
+	/* create /proc/acpi/button */
+	acpi_button_dir = proc_mkdir(ACPI_BUTTON_CLASS, acpi_root_dir);
+	if (!acpi_button_dir)
+		return -ENODEV;
+
+	/* create /proc/acpi/button/lid */
+	acpi_lid_dir = proc_mkdir(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
+	if (!acpi_lid_dir)
+		goto remove_button_dir;
+
+	/* create /proc/acpi/button/lid/LID/ */
+	acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), acpi_lid_dir);
+	if (!acpi_device_dir(device))
+		goto remove_lid_dir;
+
+	/* create /proc/acpi/button/lid/LID/state */
+	entry = proc_create_single_data(ACPI_BUTTON_FILE_STATE, S_IRUGO,
+			acpi_device_dir(device), acpi_button_state_seq_show,
+			button);
+	if (!entry)
+		goto remove_dev_dir;
+
+	return 0;
+
+remove_dev_dir:
+	remove_proc_entry(acpi_device_bid(device), acpi_lid_dir);
+	acpi_device_dir(device) = NULL;
+remove_lid_dir:
+	remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
+	acpi_lid_dir = NULL;
+remove_button_dir:
+	remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
+	acpi_button_dir = NULL;
+	return -ENODEV;
+}
+
+static void acpi_lid_remove_fs(void *data)
+{
+	struct acpi_button *button = data;
+	struct acpi_device *device = button->adev;
+
+	remove_proc_entry(ACPI_BUTTON_FILE_STATE,
+			  acpi_device_dir(device));
+	remove_proc_entry(acpi_device_bid(device),
+			  acpi_lid_dir);
+	acpi_device_dir(device) = NULL;
+	remove_proc_entry(ACPI_BUTTON_SUBCLASS_LID, acpi_button_dir);
+	acpi_lid_dir = NULL;
+	remove_proc_entry(ACPI_BUTTON_CLASS, acpi_root_dir);
+	acpi_button_dir = NULL;
+}
+
+static int devm_acpi_lid_add_fs(struct device *dev, struct acpi_button *button)
+{
+	int ret;
+
+	ret = acpi_lid_add_fs(button);
+	if (ret)
+		return ret;
+
+	return devm_add_action_or_reset(dev, acpi_lid_remove_fs, button);
+}
+
+static acpi_handle saved_lid_handle;
+static DEFINE_MUTEX(acpi_lid_lock);
+
+static void acpi_lid_save(struct acpi_device *adev)
+{
+	guard(mutex)(&acpi_lid_lock);
+
+	saved_lid_handle = adev->handle;
+}
+
+static void acpi_lid_forget(struct acpi_device *adev)
+{
+	guard(mutex)(&acpi_lid_lock);
+
+	if (saved_lid_handle == adev->handle)
+		saved_lid_handle = NULL;
+}
+
+/* Driver Interface */
+int acpi_lid_open(void)
+{
+	guard(mutex)(&acpi_lid_lock);
+
+	if (!saved_lid_handle)
+		return -ENODEV;
+
+	return acpi_lid_evaluate_state(saved_lid_handle);
+}
+EXPORT_SYMBOL(acpi_lid_open);
+
+static void acpi_lid_update_state(struct acpi_button *button, bool signal_wakeup)
+{
+	int state;
+
+	state = acpi_lid_evaluate_state(button->adev->handle);
+	if (state < 0)
+		return;
+
+	if (state && signal_wakeup)
+		acpi_pm_wakeup_event(button->dev);
+
+	acpi_lid_notify_state(button, state);
+}
+
+static void acpi_lid_initialize_state(struct acpi_button *button)
+{
+	switch (lid_init_state) {
+	case ACPI_BUTTON_LID_INIT_OPEN:
+		acpi_lid_notify_state(button, true);
+		break;
+	case ACPI_BUTTON_LID_INIT_METHOD:
+		acpi_lid_update_state(button, false);
+		break;
+	case ACPI_BUTTON_LID_INIT_IGNORE:
+	default:
+		break;
+	}
+
+	button->lid_state_initialized = true;
+}
+
+static void acpi_lid_notify(acpi_handle handle, u32 event, void *data)
+{
+	struct acpi_button *button = data;
+	struct acpi_device *device = button->adev;
+
+	if (event != ACPI_BUTTON_NOTIFY_STATUS) {
+		acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
+				  event);
+		return;
+	}
+
+	if (!button->lid_state_initialized)
+		return;
+
+	acpi_lid_update_state(button, true);
+}
+
+static void acpi_button_notify(acpi_handle handle, u32 event, void *data)
+{
+	struct acpi_button *button = data;
+	struct acpi_device *device = button->adev;
+	struct input_dev *input;
+	int keycode;
+
+	switch (event) {
+	case ACPI_BUTTON_NOTIFY_STATUS:
+		break;
+	case ACPI_BUTTON_NOTIFY_WAKE:
+		break;
+	default:
+		acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
+				  event);
+		return;
+	}
+
+	acpi_pm_wakeup_event(button->dev);
+
+	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(button->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
+static int acpi_button_suspend(struct device *dev)
+{
+	struct acpi_button *button = dev_get_drvdata(dev);
+
+	button->suspended = true;
+	return 0;
+}
+
+static int acpi_button_resume(struct device *dev)
+{
+	struct acpi_button *button = dev_get_drvdata(dev);
+	struct input_dev *input;
+
+	button->suspended = false;
+	if (button->type == ACPI_BUTTON_TYPE_LID) {
+		button->last_state = !!acpi_lid_evaluate_state(ACPI_HANDLE(dev));
+		button->last_time = ktime_get();
+		acpi_lid_initialize_state(button);
+	}
+
+	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_button *button = input_get_drvdata(input);
+
+	button->last_state = !!acpi_lid_evaluate_state(button->adev->handle);
+	button->last_time = ktime_get();
+	acpi_lid_initialize_state(button);
+
+	return 0;
+}
+
+static acpi_notify_handler acpi_button_notify_handler(struct acpi_button *button)
+{
+	if (button->type == ACPI_BUTTON_TYPE_LID)
+		return acpi_lid_notify;
+
+	return acpi_button_notify;
+}
+
+static void acpi_button_wakeup_cleanup(void *data)
+{
+	device_init_wakeup(data, false);
+}
+
+static int devm_acpi_button_init_wakeup(struct device *dev)
+{
+	device_init_wakeup(dev, true);
+	return devm_add_action_or_reset(dev, acpi_button_wakeup_cleanup, dev);
+}
+
+static void acpi_button_remove_event_handler(void *data)
+{
+	struct acpi_button *button = data;
+	struct acpi_device *adev = button->adev;
+
+	switch (adev->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:
+		if (button->gpe_enabled) {
+			dev_dbg(button->dev, "Disabling ACPI GPE%02llx\n",
+				adev->wakeup.gpe_number);
+			acpi_disable_gpe(adev->wakeup.gpe_device,
+					 adev->wakeup.gpe_number);
+		}
+		acpi_remove_notify_handler(adev->handle, ACPI_ALL_NOTIFY,
+					   acpi_button_notify_handler(button));
+		break;
+	}
+	acpi_os_wait_events_complete();
+}
+
+static int acpi_button_add_fixed_event_handler(u32 event,
+					       struct acpi_button *button)
+{
+	acpi_status status;
+
+	status = acpi_install_fixed_event_handler(event, acpi_button_event, button);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	return 0;
+}
+
+static int acpi_button_add_event_handler(struct acpi_button *button)
+{
+	struct acpi_device *adev = button->adev;
+	acpi_status status;
+
+	if (adev->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
+		return acpi_button_add_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
+							   button);
+
+	if (adev->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
+		return acpi_button_add_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
+							   button);
+
+	status = acpi_install_notify_handler(adev->handle, ACPI_ALL_NOTIFY,
+					     acpi_button_notify_handler(button),
+					     button);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	if (!adev->wakeup.flags.valid)
+		return 0;
+
+	/*
+	 * If the wakeup GPE has a handler method, enable it in case it is also
+	 * used for signaling runtime events.
+	 */
+	status = acpi_enable_gpe_cond(adev->wakeup.gpe_device,
+				      adev->wakeup.gpe_number,
+				      ACPI_GPE_DISPATCH_METHOD);
+	button->gpe_enabled = ACPI_SUCCESS(status);
+	if (button->gpe_enabled)
+		dev_dbg(button->dev, "Enabled ACPI GPE%02llx\n",
+			adev->wakeup.gpe_number);
+
+	return 0;
+}
+
+static int devm_acpi_button_add_event_handler(struct device *dev,
+					      struct acpi_button *button)
+{
+	int ret;
+
+	ret = acpi_button_add_event_handler(button);
+	if (ret)
+		return ret;
+
+	return devm_add_action_or_reset(dev, acpi_button_remove_event_handler,
+					button);
+}
+
+static int acpi_button_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct acpi_device *device = ACPI_COMPANION(dev);
+	const struct acpi_device_id *id;
+	struct acpi_button *button;
+	struct input_dev *input;
+	u8 button_type;
+	int error = 0;
+
+	id = acpi_match_acpi_device(button_device_ids, device);
+	if (!id || strcmp(acpi_device_hid(device), id->id))
+		return dev_err_probe(dev, -ENODEV, "Unsupported device\n");
+
+	button_type = id->driver_data;
+	if (button_type == ACPI_BUTTON_TYPE_LID &&
+	    lid_init_state == ACPI_BUTTON_LID_INIT_DISABLED)
+		return -ENODEV;
+
+	button = devm_kzalloc(dev, sizeof(*button), GFP_KERNEL);
+	if (!button)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, button);
+
+	button->dev = dev;
+	button->adev = device;
+	input = devm_input_allocate_device(dev);
+	if (!input)
+		return -ENOMEM;
+
+	button->input = input;
+	button->type = button_type;
+
+	switch (button_type) {
+	case ACPI_BUTTON_TYPE_LID:
+		button->class = ACPI_BUTTON_CLASS_LID;
+
+		input->name = ACPI_BUTTON_DEVICE_NAME_LID;
+		input_set_capability(input, EV_SW, SW_LID);
+		input->open = acpi_lid_input_open;
+
+		error = devm_acpi_lid_add_fs(dev, button);
+		if (error)
+			return error;
+
+		break;
+
+	case ACPI_BUTTON_TYPE_POWER:
+		button->class = ACPI_BUTTON_CLASS_POWER;
+
+		input->name = ACPI_BUTTON_DEVICE_NAME_POWER;
+		input_set_capability(input, EV_KEY, KEY_POWER);
+		input_set_capability(input, EV_KEY, KEY_WAKEUP);
+		break;
+
+	case ACPI_BUTTON_TYPE_SLEEP:
+		button->class = ACPI_BUTTON_CLASS_SLEEP;
+
+		input->name = ACPI_BUTTON_DEVICE_NAME_SLEEP;
+		input_set_capability(input, EV_KEY, KEY_SLEEP);
+		break;
+
+	default:
+		return dev_err_probe(dev, -ENODEV, "Unrecognized button type\n");
+	}
+
+	snprintf(button->phys, sizeof(button->phys), "%s/button/input0",
+		 acpi_device_hid(device));
+
+	input->phys = button->phys;
+	input->id.bustype = BUS_HOST;
+	input->id.product = button_type;
+
+	input_set_drvdata(input, button);
+	error = input_register_device(input);
+	if (error)
+		return error;
+
+	error = devm_acpi_button_init_wakeup(dev);
+	if (error)
+		return error;
+
+	error = devm_acpi_button_add_event_handler(dev, button);
+	if (error)
+		return error;
+
+	if (button_type == ACPI_BUTTON_TYPE_LID) {
+		/*
+		 * This assumes there's only one lid device, or if there are
+		 * more we only care about the last one...
+		 */
+		acpi_lid_save(device);
+	}
+
+	pr_info("%s [%s]\n", input->name, acpi_device_bid(device));
+
+	return 0;
+}
+
+static void acpi_button_remove(struct platform_device *pdev)
+{
+	struct acpi_button *button = platform_get_drvdata(pdev);
+
+	if (button->type == ACPI_BUTTON_TYPE_LID)
+		acpi_lid_forget(button->adev);
+}
+
+static int param_set_lid_init_state(const char *val,
+				    const struct kernel_param *kp)
+{
+	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 *buf, const struct kernel_param *kp)
+{
+	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,
+		  param_set_lid_init_state, param_get_lid_init_state,
+		  NULL, 0644);
+MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
+
+static int __init acpi_button_init(void)
+{
+	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
+	 * platform_driver_register() is returned from here with ACPI disabled
+	 * when this driver is built as a module.
+	 */
+	if (acpi_disabled)
+		return 0;
+
+	return platform_driver_register(&acpi_button_driver);
+}
+
+static void __exit acpi_button_exit(void)
+{
+	if (!acpi_disabled)
+		platform_driver_unregister(&acpi_button_driver);
+}
+
+module_init(acpi_button_init);
+module_exit(acpi_button_exit);