Merge tag 'acpi-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:
 "First off, the ACPICA code in the kernel is updated to upstream
  revision 20160831 that brings in a few bug fixes and cleanups. In
  particular, it is possible to mask GPEs now (and the sysfs interface
  for GPE control is fixed on top of that), problems related to the
  table loading mechanism are fixed and all code related to FADT version
  2 (which has never been part of the ACPI specification) is dropped.

  On the new features front, there is a new watchdog driver based on the
  ACPI WDAT (ACPI Watchdog Action Table), needed on some platforms to
  replace the iTCO watchdog that doesn't work there, and some UART
  devices get new definitions of built-in properties (to be accessed via
  the generic device properties API).

  Also, included is a fix for an ACPI-related PCI resorces allocation
  issue and a few problems in the EC driver and in the button and
  battery drivers are fixed.

  In addition to that, the ACPI CPPC library is updated to make batching
  of requests sent over the PCC channel possible (which reduces the PCC
  usage overhead substantially in some cases) and to support functional
  fixed hardware (FFH) type of CPPC registers access (which will allow
  CPPC to be used on x86 too in the future).

  As usual, there are some assorted fixes and cleanups too.

  Specifics:

   - Update of the ACPICA code in the kernel to upstream revision
     20160831 with the following major changes:

      * New mechanism for GPE masking.
      * Fixes for issues related to the LoadTable operator and table
        loading.
      * Fixes for issues related to so-called module-level code (MLC),
        that is AML that doesn't belong to any methods.
      * Change of the return value of the _OSI method to reflect the
        Windows behavior.
      * GAS (Generic Address Structure) support fix related to 32-bit
        FADT addresses.
      * Elimination of unnecessary FADT version 2 support.
      * ACPI tools fixes and cleanups.

     From Bob Moore, Lv Zheng, and Jung-uk Kim.

   - ACPI sysfs interface updates to fix GPE handling (on top of the new
     GPE masking mechanism in ACPICA) and issues related to table
     loading (Lv Zheng).

   - New watchdog driver based on the ACPI WDAT (ACPI Watchdog Action
     Table), needed on some platforms to replace the iTCO watchdog that
     doesn't work there and related updates of the intel_pmc_ipc,
     i2c/i801 and MFD/lcp_ich drivers (Mika Westerberg).

   - Driver core fix to prevent it from leaking secondary fwnode objects
     during device removal (Lukas Wunner).

   - New definitions of built-in properties for UART in ACPI-based x86
     SoC drivers and a 8250_dw driver quirk for the APM X-Gene SoC
     (Heikki Krogerus).

   - New device ID for the Vulcan SPI controller and constification of
     local strucures in the AMD SoC (APD) ACPI driver (Kamlakant Patel,
     Julia Lawall).

   - Fix for a bug causing the allocation of PCI resorces to fail if
     ACPI-enumerated child platform devices are registered below the PCI
     devices in question (Mika Westerberg).

   - Change of the default polarity for PCI legacy IRQs to high on
     systems booting wth ACPI on platforms with a GIC interrupt
     controller model fixing the discrepancy between the specification
     and HW behavior (Lorenzo Pieralisi).

   - Fixes for the handling of system suspend/resume in the ACPI EC
     driver and update of that driver to make it cope with the cases
     when the EC device defined in the ECDT has to be used throughout
     the entire system life cycle (Lv Zheng).

   - Update of the ACPI CPPC library to allow it to batch requests sent
     over the PCC channel (to reduce overhead), to support the fixed
     functional hardware (FFH) CPPC registers access type, to notify the
     mailbox framework about TX completions when the interrupt flag is
     set for the PCC mailbox, and to support HW-Reduced Communication
     Subspace type 2 (Ashwin Chaugule, Prashanth Prakash, Srinivas
     Pandruvada, Hoan Tran).

   - ACPI button driver fix and documentation update related to the
     handling of laptop lids (Lv Zheng).

   - ACPI battery driver initialization fix (Carlos Garnacho).

   - ACPI GPIO enumeration documentation update (Mika Westerberg).

   - Assorted updates of the core ACPI bus type code (Lukas Wunner, Lv
     Zheng).

   - Assorted cleanups of the ACPI table parsing code and the
     x86-specific ACPI code (Al Stone).

   - Fixes for assorted ACPI-related issues found in linux-next (Wei
     Yongjun)"

* tag 'acpi-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (98 commits)
  ACPI / documentation: Use recommended name in GPIO property names
  watchdog: wdat_wdt: Fix warning for using 0 as NULL
  watchdog: wdat_wdt: fix return value check in wdat_wdt_probe()
  platform/x86: intel_pmc_ipc: Do not create iTCO watchdog when WDAT table exists
  i2c: i801: Do not create iTCO watchdog when WDAT table exists
  mfd: lpc_ich: Do not create iTCO watchdog when WDAT table exists
  ACPI / bus: Adjust ACPI subsystem initialization for new table loading mode
  ACPICA: Parser: Fix a regression in LoadTable support
  ACPICA: Tables: Fix "UNLOAD" code path lock issues
  ACPI / watchdog: Add support for WDAT hardware watchdog
  ACPI / platform: Pay attention to parent device's resources
  PCI: Add pci_find_resource()
  ACPI / CPPC: Support PCC with interrupt flag
  ACPI / sysfs: Update sysfs signature handling code
  ACPI / sysfs: Fix an issue for LoadTable opcode
  ACPICA: Tables: Fix a regression in acpi_tb_find_table()
  ACPI / tables: Remove duplicated include from tables.c
  ACPI / APD: constify local structures
  x86: ACPI: make variable names clearer in acpi_parse_madt_lapic_entries()
  x86: ACPI: remove extraneous white space after semicolon
  ...

1 files changed, 82 insertions, 3 deletions

diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c
index 31abb0bdd4f2..e19f530f1083 100644
--- a/drivers/acpi/button.c
+++ b/drivers/acpi/button.c
@@ -19,6 +19,8 @@
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  */
 
+#define pr_fmt(fmt) "ACPI : button: " fmt
+
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
@@ -104,6 +106,8 @@ struct acpi_button {
 	struct input_dev *input;
 	char phys[32];			/* for input device */
 	unsigned long pushed;
+	int last_state;
+	ktime_t last_time;
 	bool suspended;
 };
 
@@ -111,6 +115,10 @@ static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier);
 static struct acpi_device *lid_device;
 static u8 lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
 
+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)
    -------------------------------------------------------------------------- */
@@ -134,10 +142,79 @@ 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;
+
+	/*
+	 * 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.
+	 */
+	if (lid_init_state != ACPI_BUTTON_LID_INIT_IGNORE ||
+	    button->last_state != !!state)
+		do_update = true;
+	else
+		do_update = false;
+
+	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 the buggy firmware */
+		pr_warn_once("The lid device is not compliant to SW_LID.\n");
 
-	/* input layer checks if event is redundant */
-	input_report_switch(button->input, SW_LID, !state);
-	input_sync(button->input);
+		/*
+		 * 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) {
+		input_report_switch(button->input, SW_LID, !state);
+		input_sync(button->input);
+		button->last_state = !!state;
+		button->last_time = ktime_get();
+	}
 
 	if (state)
 		pm_wakeup_event(&device->dev, 0);
@@ -411,6 +488,8 @@ static int acpi_button_add(struct acpi_device *device)
 		strcpy(name, ACPI_BUTTON_DEVICE_NAME_LID);
 		sprintf(class, "%s/%s",
 			ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
+		button->last_state = !!acpi_lid_evaluate_state(device);
+		button->last_time = ktime_get();
 	} else {
 		printk(KERN_ERR PREFIX "Unsupported hid [%s]\n", hid);
 		error = -ENODEV;