Merge tag 'acpi-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:

   - Update the ACPICA code in the kernel to the 20200214 upstream
     release including:

       * Fix to re-enable the sleep button after wakeup (Anchal
         Agarwal).

       * Fixes for mistakes in comments and typos (Bob Moore).

       * ASL-ASL+ converter updates (Erik Kaneda).

       * Type casting cleanups (Sven Barth).

   - Clean up the intialization of the EC driver and eliminate some dead
     code from it (Rafael Wysocki).

   - Clean up the quirk tables in the AC and battery drivers (Hans de
     Goede).

   - Fix the global lock handling on x86 to ignore unspecified bit
     positions in the global lock field (Jan Engelhardt).

   - Add a new "tiny" driver for ACPI button devices exposed by VMs to
     guest kernels to send signals directly to init (Josh Triplett).

   - Add a kernel parameter to disable ACPI BGRT on x86 (Alex Hung).

   - Make the ACPI PCI host bridge and fan drivers use scnprintf() to
     avoid potential buffer overflows (Takashi Iwai).

   - Clean up assorted pieces of code:

       * Reorder "asmlinkage" to make g++ happy (Alexey Dobriyan).

       * Drop unneeded variable initialization (Colin Ian King).

       * Add missing __acquires/__releases annotations (Jules Irenge).

       * Replace list_for_each_safe() with list_for_each_entry_safe()
         (chenqiwu)"

* tag 'acpi-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (31 commits)
  ACPICA: Update version to 20200214
  ACPI: PCI: Use scnprintf() for avoiding potential buffer overflow
  ACPI: fan: Use scnprintf() for avoiding potential buffer overflow
  ACPI: EC: Eliminate EC_FLAGS_QUERY_HANDSHAKE
  ACPI: EC: Do not clear boot_ec_is_ecdt in acpi_ec_add()
  ACPI: EC: Simplify acpi_ec_ecdt_start() and acpi_ec_init()
  ACPI: EC: Consolidate event handler installation code
  acpi/x86: ignore unspecified bit positions in the ACPI global lock field
  acpi/x86: add a kernel parameter to disable ACPI BGRT
  x86/acpi: make "asmlinkage" part first thing in the function definition
  ACPI: list_for_each_safe() -> list_for_each_entry_safe()
  ACPI: video: remove redundant assignments to variable result
  ACPI: OSL: Add missing __acquires/__releases annotations
  ACPI / battery: Cleanup Lenovo Ideapad Miix 320 DMI table entry
  ACPI / AC: Cleanup DMI quirk table
  ACPI: EC: Use fast path in acpi_ec_add() for DSDT boot EC
  ACPI: EC: Simplify acpi_ec_add()
  ACPI: EC: Drop AE_NOT_FOUND special case from ec_install_handlers()
  ACPI: EC: Avoid passing redundant argument to functions
  ACPI: EC: Avoid printing confusing messages in acpi_ec_setup()
  ...

Documentation/admin-guide/kernel-parameters.txt

@@ -450,6 +450,9 @@
 	bert_disable	[ACPI]
 			Disable BERT OS support on buggy BIOSes.
 
+	bgrt_disable	[ACPI][X86]
+			Disable BGRT to avoid flickering OEM logo.
+
 	bttv.card=	[HW,V4L] bttv (bt848 + bt878 based grabber cards)
 	bttv.radio=	Most important insmod options are available as
 			kernel args too.

arch/x86/kernel/acpi/boot.c

@@ -45,6 +45,7 @@ EXPORT_SYMBOL(acpi_disabled);
 #define PREFIX			"ACPI: "
 
 int acpi_noirq;				/* skip ACPI IRQ initialization */
+int acpi_nobgrt;			/* skip ACPI BGRT */
 int acpi_pci_disabled;		/* skip ACPI PCI scan and IRQ initialization */
 EXPORT_SYMBOL(acpi_pci_disabled);
 
@@ -1619,7 +1620,7 @@ int __init acpi_boot_init(void)
 	acpi_process_madt();
 
 	acpi_table_parse(ACPI_SIG_HPET, acpi_parse_hpet);
-	if (IS_ENABLED(CONFIG_ACPI_BGRT))
+	if (IS_ENABLED(CONFIG_ACPI_BGRT) && !acpi_nobgrt)
 		acpi_table_parse(ACPI_SIG_BGRT, acpi_parse_bgrt);
 
 	if (!acpi_noirq)
@@ -1671,6 +1672,13 @@ static int __init parse_acpi(char *arg)
 }
 early_param("acpi", parse_acpi);
 
+static int __init parse_acpi_bgrt(char *arg)
+{
+	acpi_nobgrt = true;
+	return 0;
+}
+early_param("bgrt_disable", parse_acpi_bgrt);
+
 /* FIXME: Using pci= for an ACPI parameter is a travesty. */
 static int __init parse_pci(char *arg)
 {
@@ -1740,7 +1748,7 @@ int __acpi_acquire_global_lock(unsigned int *lock)
 		new = (((old & ~0x3) + 2) + ((old >> 1) & 0x1));
 		val = cmpxchg(lock, old, new);
 	} while (unlikely (val != old));
-	return (new < 3) ? -1 : 0;
+	return ((new & 0x3) < 3) ? -1 : 0;
 }
 
 int __acpi_release_global_lock(unsigned int *lock)

arch/x86/kernel/acpi/sleep.c

@@ -43,7 +43,7 @@ unsigned long acpi_get_wakeup_address(void)
  *
  * Wrapper around acpi_enter_sleep_state() to be called by assmebly.
  */
-acpi_status asmlinkage __visible x86_acpi_enter_sleep_state(u8 state)
+asmlinkage acpi_status __visible x86_acpi_enter_sleep_state(u8 state)
 {
 	return acpi_enter_sleep_state(state);
 }

arch/x86/kernel/acpi/sleep.h

@@ -19,4 +19,4 @@ extern void do_suspend_lowlevel(void);
 
 extern int x86_acpi_suspend_lowlevel(void);
 
-acpi_status asmlinkage x86_acpi_enter_sleep_state(u8 state);
+asmlinkage acpi_status x86_acpi_enter_sleep_state(u8 state);

drivers/acpi/Kconfig

@@ -190,6 +190,30 @@ config ACPI_BUTTON
 	  To compile this driver as a module, choose M here:
 	  the module will be called button.
 
+config ACPI_TINY_POWER_BUTTON
+	tristate "Tiny Power Button Driver"
+	depends on !ACPI_BUTTON
+	help
+	  This driver provides a tiny alternative to the ACPI Button driver.
+	  The tiny power button driver only handles the power button. Rather
+	  than notifying userspace via the input layer or a netlink event, this
+	  driver directly signals the init process to shut down.
+
+	  This driver is particularly suitable for cloud and VM environments,
+	  which use a simulated power button to initiate a controlled poweroff,
+	  but which may not want to run a separate userspace daemon to process
+	  input events.
+
+config ACPI_TINY_POWER_BUTTON_SIGNAL
+	int "Tiny Power Button Signal"
+	depends on ACPI_TINY_POWER_BUTTON
+	default 38
+	help
+	  Default signal to send to init in response to the power button.
+
+	  Likely values here include 38 (SIGRTMIN+4) to power off, or 2
+	  (SIGINT) to simulate Ctrl+Alt+Del.
+
 config ACPI_VIDEO
 	tristate "Video"
 	depends on X86 && BACKLIGHT_CLASS_DEVICE

drivers/acpi/Makefile

@@ -71,6 +71,7 @@ obj-$(CONFIG_ACPI_IPMI)		+= acpi_ipmi.o
 
 obj-$(CONFIG_ACPI_AC) 		+= ac.o
 obj-$(CONFIG_ACPI_BUTTON)	+= button.o
+obj-$(CONFIG_ACPI_TINY_POWER_BUTTON)	+= tiny-power-button.o
 obj-$(CONFIG_ACPI_FAN)		+= fan.o
 obj-$(CONFIG_ACPI_VIDEO)	+= video.o
 obj-$(CONFIG_ACPI_TAD)		+= acpi_tad.o

drivers/acpi/ac.c

@@ -293,29 +293,30 @@ static int __init ac_do_not_check_pmic_quirk(const struct dmi_system_id *d)
 	return 0;
 }
 
+/* Please keep this list alphabetically sorted */
 static const struct dmi_system_id ac_dmi_table[]  __initconst = {
 	{
-	/* Thinkpad e530 */
-	.callback = thinkpad_e530_quirk,
+		/* ECS EF20EA, AXP288 PMIC but uses separate fuel-gauge */
+		.callback = ac_do_not_check_pmic_quirk,
 		.matches = {
-		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
-		DMI_MATCH(DMI_PRODUCT_NAME, "32597CG"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "EF20EA"),
 		},
 	},
 	{
-		/* ECS EF20EA */
+		/* Lenovo Ideapad Miix 320, AXP288 PMIC, separate fuel-gauge */
 		.callback = ac_do_not_check_pmic_quirk,
 		.matches = {
-			DMI_MATCH(DMI_PRODUCT_NAME, "EF20EA"),
+			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "80XF"),
+			DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo MIIX 320-10ICR"),
 		},
 	},
 	{
-		/* Lenovo Ideapad Miix 320 */
-		.callback = ac_do_not_check_pmic_quirk,
+		/* Lenovo Thinkpad e530, see comment in acpi_ac_notify() */
+		.callback = thinkpad_e530_quirk,
 		.matches = {
-		  DMI_EXACT_MATCH(DMI_SYS_VENDOR, "LENOVO"),
-		  DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "80XF"),
-		  DMI_EXACT_MATCH(DMI_PRODUCT_VERSION, "Lenovo MIIX 320-10ICR"),
+			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "32597CG"),
 		},
 	},
 	{},

drivers/acpi/acpi_video.c

@@ -943,7 +943,7 @@ acpi_video_init_brightness(struct acpi_video_device *device)
 	int i, max_level = 0;
 	unsigned long long level, level_old;
 	struct acpi_video_device_brightness *br = NULL;
-	int result = -EINVAL;
+	int result;
 
 	result = acpi_video_get_levels(device->dev, &br, &max_level);
 	if (result)

drivers/acpi/acpica/acconvert.h

@@ -65,9 +65,7 @@ void cg_write_aml_comment(union acpi_parse_object *op);
 /*
  * cvparser
  */
-void
-cv_init_file_tree(struct acpi_table_header *table,
-		  u8 *aml_start, u32 aml_length);
+void cv_init_file_tree(struct acpi_table_header *table, FILE * root_file);
 
 void cv_clear_op_comments(union acpi_parse_object *op);
 

drivers/acpi/acpica/acmacros.h

@@ -477,7 +477,7 @@
 #define ASL_CV_PRINT_ONE_COMMENT(a,b,c,d) cv_print_one_comment_type (a,b,c,d);
 #define ASL_CV_PRINT_ONE_COMMENT_LIST(a,b) cv_print_one_comment_list (a,b);
 #define ASL_CV_FILE_HAS_SWITCHED(a)       cv_file_has_switched(a)
-#define ASL_CV_INIT_FILETREE(a,b,c)      cv_init_file_tree(a,b,c);
+#define ASL_CV_INIT_FILETREE(a,b)      cv_init_file_tree(a,b);
 
 #else
 
@@ -492,7 +492,7 @@
 #define ASL_CV_PRINT_ONE_COMMENT(a,b,c,d)
 #define ASL_CV_PRINT_ONE_COMMENT_LIST(a,b)
 #define ASL_CV_FILE_HAS_SWITCHED(a)       0
-#define ASL_CV_INIT_FILETREE(a,b,c)
+#define ASL_CV_INIT_FILETREE(a,b)
 
 #endif
 

drivers/acpi/acpica/evevent.c

@@ -130,7 +130,7 @@ static acpi_status acpi_ev_fixed_event_initialize(void)
 
 	/*
 	 * Initialize the structure that keeps track of fixed event handlers and
-	 * enable the fixed events.
+	 * disable all of the fixed events.
 	 */
 	for (i = 0; i < ACPI_NUM_FIXED_EVENTS; i++) {
 		acpi_gbl_fixed_event_handlers[i].handler = NULL;

drivers/acpi/acpica/hwsleep.c

@@ -300,6 +300,18 @@ acpi_status acpi_hw_legacy_wake(u8 sleep_state)
 				    [ACPI_EVENT_POWER_BUTTON].
 				    status_register_id, ACPI_CLEAR_STATUS);
 
+	/* Enable sleep button */
+
+	(void)
+	    acpi_write_bit_register(acpi_gbl_fixed_event_info
+				    [ACPI_EVENT_SLEEP_BUTTON].
+				    enable_register_id, ACPI_ENABLE_EVENT);
+
+	(void)
+	    acpi_write_bit_register(acpi_gbl_fixed_event_info
+				    [ACPI_EVENT_SLEEP_BUTTON].
+				    status_register_id, ACPI_CLEAR_STATUS);
+
 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING);
 	return_ACPI_STATUS(status);
 }

drivers/acpi/acpica/nsnames.c

@@ -164,7 +164,7 @@ acpi_ns_handle_to_pathname(acpi_handle target_handle,
 	/* Build the path in the caller buffer */
 
 	(void)acpi_ns_build_normalized_path(node, buffer->pointer,
-					    required_size, no_trailing);
+					    (u32)required_size, no_trailing);
 
 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%s [%X]\n",
 			  (char *)buffer->pointer, (u32) required_size));
@@ -315,7 +315,7 @@ char *acpi_ns_get_normalized_pathname(struct acpi_namespace_node *node,
 
 	/* Build the path in the allocated buffer */
 
-	(void)acpi_ns_build_normalized_path(node, name_buffer, size,
+	(void)acpi_ns_build_normalized_path(node, name_buffer, (u32)size,
 					    no_trailing);
 
 	ACPI_DEBUG_PRINT_RAW((ACPI_DB_NAMES, "%s: Path \"%s\"\n",
@@ -346,7 +346,7 @@ char *acpi_ns_build_prefixed_pathname(union acpi_generic_state *prefix_scope,
 	char *full_path = NULL;
 	char *external_path = NULL;
 	char *prefix_path = NULL;
-	u32 prefix_path_length = 0;
+	acpi_size prefix_path_length = 0;
 
 	/* If there is a prefix, get the pathname to it */
 

drivers/acpi/acpica/nsxfname.c

@@ -516,7 +516,7 @@ acpi_status acpi_install_method(u8 *buffer)
 
 	method_flags = *parser_state.aml++;
 	aml_start = parser_state.aml;
-	aml_length = ACPI_PTR_DIFF(parser_state.pkg_end, aml_start);
+	aml_length = (u32)ACPI_PTR_DIFF(parser_state.pkg_end, aml_start);
 
 	/*
 	 * Allocate resources up-front. We don't want to have to delete a new

drivers/acpi/acpica/tbxface.c

@@ -202,14 +202,14 @@ ACPI_EXPORT_SYMBOL_INIT(acpi_reallocate_root_table)
  *
  * PARAMETERS:  signature           - ACPI signature of needed table
  *              instance            - Which instance (for SSDTs)
- *              out_table_header    - The pointer to the table header to fill
+ *              out_table_header    - The pointer to the where the table header
+ *                                    is returned
  *
- * RETURN:      Status and pointer to mapped table header
+ * RETURN:      Status and a copy of the table header
  *
- * DESCRIPTION: Finds an ACPI table header.
- *
- * NOTE:        Caller is responsible in unmapping the header with
- *              acpi_os_unmap_memory
+ * DESCRIPTION: Finds and returns an ACPI table header. Caller provides the
+ *              memory where a copy of the header is to be returned
+ *              (fixed length).
  *
  ******************************************************************************/
 acpi_status

drivers/acpi/acpica/utobject.c

@@ -44,7 +44,7 @@ acpi_ut_get_element_length(u8 object_type,
  *
  * NOTE:        We always allocate the worst-case object descriptor because
  *              these objects are cached, and we want them to be
- *              one-size-satisifies-any-request. This in itself may not be
+ *              one-size-satisfies-any-request. This in itself may not be
  *              the most memory efficient, but the efficiency of the object
  *              cache should more than make up for this!
  *

drivers/acpi/battery.c

@@ -1365,19 +1365,19 @@ static const struct dmi_system_id bat_dmi_table[] __initconst = {
 		},
 	},
 	{
-		/* ECS EF20EA */
+		/* ECS EF20EA, AXP288 PMIC but uses separate fuel-gauge */
 		.callback = battery_do_not_check_pmic_quirk,
 		.matches = {
 			DMI_MATCH(DMI_PRODUCT_NAME, "EF20EA"),
 		},
 	},
 	{
-		/* Lenovo Ideapad Miix 320 */
+		/* Lenovo Ideapad Miix 320, AXP288 PMIC, separate fuel-gauge */
 		.callback = battery_do_not_check_pmic_quirk,
 		.matches = {
-		  DMI_EXACT_MATCH(DMI_SYS_VENDOR, "LENOVO"),
-		  DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "80XF"),
-		  DMI_EXACT_MATCH(DMI_PRODUCT_VERSION, "Lenovo MIIX 320-10ICR"),
+			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "80XF"),
+			DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo MIIX 320-10ICR"),
 		},
 	},
 	{},

drivers/acpi/button.c

@@ -30,17 +30,14 @@
 #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
 

drivers/acpi/ec.c

@@ -182,7 +182,6 @@ static bool boot_ec_is_ecdt = false;
 static struct workqueue_struct *ec_wq;
 static struct workqueue_struct *ec_query_wq;
 
-static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */
 static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */
 static int EC_FLAGS_IGNORE_DSDT_GPE; /* Needs ECDT GPE as correction setting */
 static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */
@@ -690,21 +689,9 @@ static void advance_transaction(struct acpi_ec *ec)
 			wakeup = true;
 		}
 		goto out;
-	} else {
-		if (EC_FLAGS_QUERY_HANDSHAKE &&
-		    !(status & ACPI_EC_FLAG_SCI) &&
-		    (t->command == ACPI_EC_COMMAND_QUERY)) {
-			ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
-			t->rdata[t->ri++] = 0x00;
-			ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
-			ec_dbg_evt("Command(%s) completed by software",
-				   acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
-			wakeup = true;
-		} else if ((status & ACPI_EC_FLAG_IBF) == 0) {
+	} else if (!(status & ACPI_EC_FLAG_IBF)) {
 		acpi_ec_write_cmd(ec, t->command);
 		ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
-		} else
-			goto err;
 		goto out;
 	}
 err:
@@ -1427,57 +1414,45 @@ ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 	return AE_CTRL_TERMINATE;
 }
 
-static void install_gpe_event_handler(struct acpi_ec *ec)
+static bool install_gpe_event_handler(struct acpi_ec *ec)
 {
-	acpi_status status =
-		acpi_install_gpe_raw_handler(NULL, ec->gpe,
+	acpi_status status;
+
+	status = acpi_install_gpe_raw_handler(NULL, ec->gpe,
 					      ACPI_GPE_EDGE_TRIGGERED,
-					     &acpi_ec_gpe_handler,
-					     ec);
-	if (ACPI_SUCCESS(status)) {
-		/* This is not fatal as we can poll EC events */
-		set_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags);
-		acpi_ec_leave_noirq(ec);
-		if (test_bit(EC_FLAGS_STARTED, &ec->flags) &&
-		    ec->reference_count >= 1)
+					      &acpi_ec_gpe_handler, ec);
+	if (ACPI_FAILURE(status))
+		return false;
+
+	if (test_bit(EC_FLAGS_STARTED, &ec->flags) && ec->reference_count >= 1)
 		acpi_ec_enable_gpe(ec, true);
-	}
+
+	return true;
 }
 
-/* ACPI reduced hardware platforms use a GpioInt specified in _CRS. */
-static int install_gpio_irq_event_handler(struct acpi_ec *ec,
-					  struct acpi_device *device)
+static bool install_gpio_irq_event_handler(struct acpi_ec *ec)
 {
-	int irq = acpi_dev_gpio_irq_get(device, 0);
-	int ret;
-
-	if (irq < 0)
-		return irq;
-
-	ret = request_irq(irq, acpi_ec_irq_handler, IRQF_SHARED,
-			  "ACPI EC", ec);
-
-	/*
-	 * Unlike the GPE case, we treat errors here as fatal, we'll only
-	 * implement GPIO polling if we find a case that needs it.
-	 */
-	if (ret < 0)
-		return ret;
-
-	ec->irq = irq;
-	set_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags);
-	acpi_ec_leave_noirq(ec);
-
-	return 0;
+	return request_irq(ec->irq, acpi_ec_irq_handler, IRQF_SHARED,
+			   "ACPI EC", ec) >= 0;
 }
 
-/*
- * Note: This function returns an error code only when the address space
- *       handler is not installed, which means "not able to handle
- *       transactions".
+/**
+ * ec_install_handlers - Install service callbacks and register query methods.
+ * @ec: Target EC.
+ * @device: ACPI device object corresponding to @ec.
+ *
+ * Install a handler for the EC address space type unless it has been installed
+ * already.  If @device is not NULL, also look for EC query methods in the
+ * namespace and register them, and install an event (either GPE or GPIO IRQ)
+ * handler for the EC, if possible.
+ *
+ * Return:
+ * -ENODEV if the address space handler cannot be installed, which means
+ *  "unable to handle transactions",
+ * -EPROBE_DEFER if GPIO IRQ acquisition needs to be deferred,
+ * or 0 (success) otherwise.
  */
-static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device,
-			       bool handle_events)
+static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device)
 {
 	acpi_status status;
 
@@ -1490,26 +1465,28 @@ static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device,
 							    &acpi_ec_space_handler,
 							    NULL, ec);
 		if (ACPI_FAILURE(status)) {
-			if (status == AE_NOT_FOUND) {
-				/*
-				 * Maybe OS fails in evaluating the _REG
-				 * object. The AE_NOT_FOUND error will be
-				 * ignored and OS * continue to initialize
-				 * EC.
-				 */
-				pr_err("Fail in evaluating the _REG object"
-					" of EC device. Broken bios is suspected.\n");
-			} else {
 			acpi_ec_stop(ec, false);
 			return -ENODEV;
 		}
-		}
 		set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags);
 	}
 
-	if (!handle_events)
+	if (!device)
 		return 0;
 
+	if (ec->gpe < 0) {
+		/* ACPI reduced hardware platforms use a GpioInt from _CRS. */
+		int irq = acpi_dev_gpio_irq_get(device, 0);
+		/*
+		 * Bail out right away for deferred probing or complete the
+		 * initialization regardless of any other errors.
+		 */
+		if (irq == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+		else if (irq >= 0)
+			ec->irq = irq;
+	}
+
 	if (!test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) {
 		/* Find and register all query methods */
 		acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
@@ -1518,16 +1495,21 @@ static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device,
 		set_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags);
 	}
 	if (!test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) {
-		if (ec->gpe >= 0) {
-			install_gpe_event_handler(ec);
-		} else if (device) {
-			int ret = install_gpio_irq_event_handler(ec, device);
+		bool ready = false;
 
-			if (ret)
-				return ret;
-		} else { /* No GPE and no GpioInt? */
-			return -ENODEV;
+		if (ec->gpe >= 0)
+			ready = install_gpe_event_handler(ec);
+		else if (ec->irq >= 0)
+			ready = install_gpio_irq_event_handler(ec);
+
+		if (ready) {
+			set_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags);
+			acpi_ec_leave_noirq(ec);
 		}
+		/*
+		 * Failures to install an event handler are not fatal, because
+		 * the EC can be polled for events.
+		 */
 	}
 	/* EC is fully operational, allow queries */
 	acpi_ec_enable_event(ec);
@@ -1574,61 +1556,46 @@ static void ec_remove_handlers(struct acpi_ec *ec)
 	}
 }
 
-static int acpi_ec_setup(struct acpi_ec *ec, struct acpi_device *device,
-			 bool handle_events)
+static int acpi_ec_setup(struct acpi_ec *ec, struct acpi_device *device)
 {
 	int ret;
 
-	ret = ec_install_handlers(ec, device, handle_events);
+	ret = ec_install_handlers(ec, device);
 	if (ret)
 		return ret;
 
 	/* First EC capable of handling transactions */
-	if (!first_ec) {
+	if (!first_ec)
 		first_ec = ec;
-		acpi_handle_info(first_ec->handle, "Used as first EC\n");
-	}
 
-	acpi_handle_info(ec->handle,
-			 "GPE=0x%x, IRQ=%d, EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n",
-			 ec->gpe, ec->irq, ec->command_addr, ec->data_addr);
-	return ret;
-}
-
-static bool acpi_ec_ecdt_get_handle(acpi_handle *phandle)
-{
-	struct acpi_table_ecdt *ecdt_ptr;
-	acpi_status status;
-	acpi_handle handle;
+	pr_info("EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", ec->command_addr,
+		ec->data_addr);
 
-	status = acpi_get_table(ACPI_SIG_ECDT, 1,
-				(struct acpi_table_header **)&ecdt_ptr);
-	if (ACPI_FAILURE(status))
-		return false;
-
-	status = acpi_get_handle(NULL, ecdt_ptr->id, &handle);
-	if (ACPI_FAILURE(status))
-		return false;
+	if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) {
+		if (ec->gpe >= 0)
+			pr_info("GPE=0x%x\n", ec->gpe);
+		else
+			pr_info("IRQ=%d\n", ec->irq);
+	}
 
-	*phandle = handle;
-	return true;
+	return ret;
 }
 
 static int acpi_ec_add(struct acpi_device *device)
 {
-	struct acpi_ec *ec = NULL;
-	bool dep_update = true;
-	acpi_status status;
+	struct acpi_ec *ec;
 	int ret;
 
 	strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 	strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 
-	if (!strcmp(acpi_device_hid(device), ACPI_ECDT_HID)) {
-		boot_ec_is_ecdt = true;
+	if ((boot_ec && boot_ec->handle == device->handle) ||
+	    !strcmp(acpi_device_hid(device), ACPI_ECDT_HID)) {
+		/* Fast path: this device corresponds to the boot EC. */
 		ec = boot_ec;
-		dep_update = false;
 	} else {
+		acpi_status status;
+
 		ec = acpi_ec_alloc();
 		if (!ec)
 			return -ENOMEM;
@@ -1636,12 +1603,11 @@ static int acpi_ec_add(struct acpi_device *device)
 		status = ec_parse_device(device->handle, 0, ec, NULL);
 		if (status != AE_CTRL_TERMINATE) {
 			ret = -EINVAL;
-			goto err_alloc;
+			goto err;
 		}
 
 		if (boot_ec && ec->command_addr == boot_ec->command_addr &&
 		    ec->data_addr == boot_ec->data_addr) {
-			boot_ec_is_ecdt = false;
 			/*
 			 * Trust PNP0C09 namespace location rather than
 			 * ECDT ID. But trust ECDT GPE rather than _GPE
@@ -1655,15 +1621,18 @@ static int acpi_ec_add(struct acpi_device *device)
 		}
 	}
 
-	ret = acpi_ec_setup(ec, device, true);
+	ret = acpi_ec_setup(ec, device);
 	if (ret)
-		goto err_query;
+		goto err;
 
 	if (ec == boot_ec)
 		acpi_handle_info(boot_ec->handle,
-				 "Boot %s EC used to handle transactions and events\n",
+				 "Boot %s EC initialization complete\n",
 				 boot_ec_is_ecdt ? "ECDT" : "DSDT");
 
+	acpi_handle_info(ec->handle,
+			 "EC: Used to handle transactions and events\n");
+
 	device->driver_data = ec;
 
 	ret = !!request_region(ec->data_addr, 1, "EC data");
@@ -1671,19 +1640,16 @@ static int acpi_ec_add(struct acpi_device *device)
 	ret = !!request_region(ec->command_addr, 1, "EC cmd");
 	WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
 
-	if (dep_update) {
 	/* Reprobe devices depending on the EC */
 	acpi_walk_dep_device_list(ec->handle);
-	}
+
 	acpi_handle_debug(ec->handle, "enumerated.\n");
 	return 0;
 
-err_query:
-	if (ec != boot_ec)
-		acpi_ec_remove_query_handlers(ec, true, 0);
-err_alloc:
+err:
 	if (ec != boot_ec)
 		acpi_ec_free(ec);
+
 	return ret;
 }
 
@@ -1775,7 +1741,7 @@ void __init acpi_ec_dsdt_probe(void)
 	 * At this point, the GPE is not fully initialized, so do not to
 	 * handle the events.
 	 */
-	ret = acpi_ec_setup(ec, NULL, false);
+	ret = acpi_ec_setup(ec, NULL);
 	if (ret) {
 		acpi_ec_free(ec);
 		return;
@@ -1788,52 +1754,43 @@ void __init acpi_ec_dsdt_probe(void)
 }
 
 /*
- * If the DSDT EC is not functioning, we still need to prepare a fully
- * functioning ECDT EC first in order to handle the events.
- * https://bugzilla.kernel.org/show_bug.cgi?id=115021
+ * acpi_ec_ecdt_start - Finalize the boot ECDT EC initialization.
+ *
+ * First, look for an ACPI handle for the boot ECDT EC if acpi_ec_add() has not
+ * found a matching object in the namespace.
+ *
+ * Next, in case the DSDT EC is not functioning, it is still necessary to
+ * provide a functional ECDT EC to handle events, so add an extra device object
+ * to represent it (see https://bugzilla.kernel.org/show_bug.cgi?id=115021).
+ *
+ * This is useful on platforms with valid ECDT and invalid DSDT EC settings,
+ * like ASUS X550ZE (see https://bugzilla.kernel.org/show_bug.cgi?id=196847).
  */
-static int __init acpi_ec_ecdt_start(void)
+static void __init acpi_ec_ecdt_start(void)
 {
+	struct acpi_table_ecdt *ecdt_ptr;
 	acpi_handle handle;
+	acpi_status status;
 
-	if (!boot_ec)
-		return -ENODEV;
-	/* In case acpi_ec_ecdt_start() is called after acpi_ec_add() */
-	if (!boot_ec_is_ecdt)
-		return -ENODEV;
+	/* Bail out if a matching EC has been found in the namespace. */
+	if (!boot_ec || boot_ec->handle != ACPI_ROOT_OBJECT)
+		return;
 
-	/*
-	 * At this point, the namespace and the GPE is initialized, so
-	 * start to find the namespace objects and handle the events.
-	 *
-	 * Note: ec->handle can be valid if this function is called after
-	 * acpi_ec_add(), hence the fast path.
-	 */
-	if (boot_ec->handle == ACPI_ROOT_OBJECT) {
-		if (!acpi_ec_ecdt_get_handle(&handle))
-			return -ENODEV;
-		boot_ec->handle = handle;
-	}
+	/* Look up the object pointed to from the ECDT in the namespace. */
+	status = acpi_get_table(ACPI_SIG_ECDT, 1,
+				(struct acpi_table_header **)&ecdt_ptr);
+	if (ACPI_FAILURE(status))
+		return;
 
-	/* Register to ACPI bus with PM ops attached */
-	return acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC);
-}
+	status = acpi_get_handle(NULL, ecdt_ptr->id, &handle);
+	if (ACPI_FAILURE(status))
+		return;
 
-#if 0
-/*
- * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not
- * set, for which case, we complete the QR_EC without issuing it to the
- * firmware.
- * https://bugzilla.kernel.org/show_bug.cgi?id=82611
- * https://bugzilla.kernel.org/show_bug.cgi?id=97381
- */
-static int ec_flag_query_handshake(const struct dmi_system_id *id)
-{
-	pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n");
-	EC_FLAGS_QUERY_HANDSHAKE = 1;
-	return 0;
+	boot_ec->handle = handle;
+
+	/* Add a special ACPI device object to represent the boot EC. */
+	acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC);
 }
-#endif
 
 /*
  * On some hardware it is necessary to clear events accumulated by the EC during
@@ -1962,7 +1919,7 @@ void __init acpi_ec_ecdt_probe(void)
 	 * At this point, the namespace is not initialized, so do not find
 	 * the namespace objects, or handle the events.
 	 */
-	ret = acpi_ec_setup(ec, NULL, false);
+	ret = acpi_ec_setup(ec, NULL);
 	if (ret) {
 		acpi_ec_free(ec);
 		return;
@@ -2165,14 +2122,13 @@ static const struct dmi_system_id acpi_ec_no_wakeup[] = {
 	{ },
 };
 
-int __init acpi_ec_init(void)
+void __init acpi_ec_init(void)
 {
 	int result;
-	int ecdt_fail, dsdt_fail;
 
 	result = acpi_ec_init_workqueues();
 	if (result)
-		return result;
+		return;
 
 	/*
 	 * Disable EC wakeup on following systems to prevent periodic
@@ -2183,16 +2139,10 @@ int __init acpi_ec_init(void)
 		pr_debug("Disabling EC wakeup on suspend-to-idle\n");
 	}
 
-	/* Drivers must be started after acpi_ec_query_init() */
-	dsdt_fail = acpi_bus_register_driver(&acpi_ec_driver);
-	/*
-	 * Register ECDT to ACPI bus only when PNP0C09 probe fails. This is
-	 * useful for platforms (confirmed on ASUS X550ZE) with valid ECDT
-	 * settings but invalid DSDT settings.
-	 * https://bugzilla.kernel.org/show_bug.cgi?id=196847
-	 */
-	ecdt_fail = acpi_ec_ecdt_start();
-	return ecdt_fail && dsdt_fail ? -ENODEV : 0;
+	/* Driver must be registered after acpi_ec_init_workqueues(). */
+	acpi_bus_register_driver(&acpi_ec_driver);
+
+	acpi_ec_ecdt_start();
 }
 
 /* EC driver currently not unloadable */

drivers/acpi/fan.c

@@ -276,29 +276,29 @@ static ssize_t show_state(struct device *dev, struct device_attribute *attr, cha
 	int count;
 
 	if (fps->control == 0xFFFFFFFF || fps->control > 100)
-		count = snprintf(buf, PAGE_SIZE, "not-defined:");
+		count = scnprintf(buf, PAGE_SIZE, "not-defined:");
 	else
-		count = snprintf(buf, PAGE_SIZE, "%lld:", fps->control);
+		count = scnprintf(buf, PAGE_SIZE, "%lld:", fps->control);
 
 	if (fps->trip_point == 0xFFFFFFFF || fps->trip_point > 9)
-		count += snprintf(&buf[count], PAGE_SIZE, "not-defined:");
+		count += scnprintf(&buf[count], PAGE_SIZE - count, "not-defined:");
 	else
-		count += snprintf(&buf[count], PAGE_SIZE, "%lld:", fps->trip_point);
+		count += scnprintf(&buf[count], PAGE_SIZE - count, "%lld:", fps->trip_point);
 
 	if (fps->speed == 0xFFFFFFFF)
-		count += snprintf(&buf[count], PAGE_SIZE, "not-defined:");
+		count += scnprintf(&buf[count], PAGE_SIZE - count, "not-defined:");
 	else
-		count += snprintf(&buf[count], PAGE_SIZE, "%lld:", fps->speed);
+		count += scnprintf(&buf[count], PAGE_SIZE - count, "%lld:", fps->speed);
 
 	if (fps->noise_level == 0xFFFFFFFF)
-		count += snprintf(&buf[count], PAGE_SIZE, "not-defined:");
+		count += scnprintf(&buf[count], PAGE_SIZE - count, "not-defined:");
 	else
-		count += snprintf(&buf[count], PAGE_SIZE, "%lld:", fps->noise_level * 100);
+		count += scnprintf(&buf[count], PAGE_SIZE - count, "%lld:", fps->noise_level * 100);
 
 	if (fps->power == 0xFFFFFFFF)
-		count += snprintf(&buf[count], PAGE_SIZE, "not-defined\n");
+		count += scnprintf(&buf[count], PAGE_SIZE - count, "not-defined\n");
 	else
-		count += snprintf(&buf[count], PAGE_SIZE, "%lld\n", fps->power);
+		count += scnprintf(&buf[count], PAGE_SIZE - count, "%lld\n", fps->power);
 
 	return count;
 }

drivers/acpi/internal.h

@@ -190,7 +190,7 @@ extern struct acpi_ec *first_ec;
 /* External interfaces use first EC only, so remember */
 typedef int (*acpi_ec_query_func) (void *data);
 
-int acpi_ec_init(void);
+void acpi_ec_init(void);
 void acpi_ec_ecdt_probe(void);
 void acpi_ec_dsdt_probe(void);
 void acpi_ec_block_transactions(void);

drivers/acpi/osl.c

@@ -1598,6 +1598,7 @@ void acpi_os_delete_lock(acpi_spinlock handle)
  */
 
 acpi_cpu_flags acpi_os_acquire_lock(acpi_spinlock lockp)
+	__acquires(lockp)
 {
 	acpi_cpu_flags flags;
 	spin_lock_irqsave(lockp, flags);
@@ -1609,6 +1610,7 @@ acpi_cpu_flags acpi_os_acquire_lock(acpi_spinlock lockp)
  */
 
 void acpi_os_release_lock(acpi_spinlock lockp, acpi_cpu_flags flags)
+	__releases(lockp)
 {
 	spin_unlock_irqrestore(lockp, flags);
 }

drivers/acpi/pci_root.c

@@ -153,7 +153,7 @@ static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
 	buf[0] = '\0';
 	for (i = 0, entry = table; i < size; i++, entry++)
 		if (word & entry->bit)
-			len += snprintf(buf + len, sizeof(buf) - len, "%s%s",
+			len += scnprintf(buf + len, sizeof(buf) - len, "%s%s",
 					len ? " " : "", entry->desc);
 
 	dev_info(&root->device->dev, "_OSC: %s [%s]\n", msg, buf);

drivers/acpi/proc.c

@@ -22,14 +22,13 @@ ACPI_MODULE_NAME("sleep")
 static int
 acpi_system_wakeup_device_seq_show(struct seq_file *seq, void *offset)
 {
-	struct list_head *node, *next;
+	struct acpi_device *dev, *tmp;
 
 	seq_printf(seq, "Device\tS-state\t  Status   Sysfs node\n");
 
 	mutex_lock(&acpi_device_lock);
-	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
-		struct acpi_device *dev =
-		    container_of(node, struct acpi_device, wakeup_list);
+	list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
+				 wakeup_list) {
 		struct acpi_device_physical_node *entry;
 
 		if (!dev->wakeup.flags.valid)
@@ -96,7 +95,7 @@ acpi_system_write_wakeup_device(struct file *file,
 				const char __user * buffer,
 				size_t count, loff_t * ppos)
 {
-	struct list_head *node, *next;
+	struct acpi_device *dev, *tmp;
 	char strbuf[5];
 	char str[5] = "";
 
@@ -109,9 +108,8 @@ acpi_system_write_wakeup_device(struct file *file,
 	sscanf(strbuf, "%s", str);
 
 	mutex_lock(&acpi_device_lock);
-	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
-		struct acpi_device *dev =
-		    container_of(node, struct acpi_device, wakeup_list);
+	list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
+				 wakeup_list) {
 		if (!dev->wakeup.flags.valid)
 			continue;
 

drivers/acpi/tiny-power-button.c

+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <linux/module.h>
+#include <linux/sched/signal.h>
+#include <linux/acpi.h>
+#include <acpi/button.h>
+
+ACPI_MODULE_NAME("tiny-power-button");
+MODULE_AUTHOR("Josh Triplett");
+MODULE_DESCRIPTION("ACPI Tiny Power Button Driver");
+MODULE_LICENSE("GPL");
+
+static int power_signal __read_mostly = CONFIG_ACPI_TINY_POWER_BUTTON_SIGNAL;
+module_param(power_signal, int, 0644);
+MODULE_PARM_DESC(power_signal, "Power button sends this signal to init");
+
+static const struct acpi_device_id tiny_power_button_device_ids[] = {
+	{ ACPI_BUTTON_HID_POWER, 0 },
+	{ ACPI_BUTTON_HID_POWERF, 0 },
+	{ "", 0 },
+};
+MODULE_DEVICE_TABLE(acpi, tiny_power_button_device_ids);
+
+static int acpi_noop_add_remove(struct acpi_device *device)
+{
+	return 0;
+}
+
+static void acpi_tiny_power_button_notify(struct acpi_device *device, u32 event)
+{
+	kill_cad_pid(power_signal, 1);
+}
+
+static struct acpi_driver acpi_tiny_power_button_driver = {
+	.name = "tiny-power-button",
+	.class = "tiny-power-button",
+	.ids = tiny_power_button_device_ids,
+	.ops = {
+		.add = acpi_noop_add_remove,
+		.remove = acpi_noop_add_remove,
+		.notify = acpi_tiny_power_button_notify,
+	},
+};
+
+module_driver(acpi_tiny_power_button_driver,
+		acpi_bus_register_driver,
+		acpi_bus_unregister_driver);

drivers/acpi/wakeup.c

@@ -30,12 +30,10 @@ ACPI_MODULE_NAME("wakeup_devices")
  */
 void acpi_enable_wakeup_devices(u8 sleep_state)
 {
-	struct list_head *node, *next;
-
-	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
-		struct acpi_device *dev =
-			container_of(node, struct acpi_device, wakeup_list);
+	struct acpi_device *dev, *tmp;
 
+	list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
+				 wakeup_list) {
 		if (!dev->wakeup.flags.valid
 		    || sleep_state > (u32) dev->wakeup.sleep_state
 		    || !(device_may_wakeup(&dev->dev)
@@ -57,12 +55,10 @@ void acpi_enable_wakeup_devices(u8 sleep_state)
  */
 void acpi_disable_wakeup_devices(u8 sleep_state)
 {
-	struct list_head *node, *next;
-
-	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
-		struct acpi_device *dev =
-			container_of(node, struct acpi_device, wakeup_list);
+	struct acpi_device *dev, *tmp;
 
+	list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
+				 wakeup_list) {
 		if (!dev->wakeup.flags.valid
 		    || sleep_state > (u32) dev->wakeup.sleep_state
 		    || !(device_may_wakeup(&dev->dev)
@@ -79,13 +75,11 @@ void acpi_disable_wakeup_devices(u8 sleep_state)
 
 int __init acpi_wakeup_device_init(void)
 {
-	struct list_head *node, *next;
+	struct acpi_device *dev, *tmp;
 
 	mutex_lock(&acpi_device_lock);
-	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
-		struct acpi_device *dev = container_of(node,
-						       struct acpi_device,
-						       wakeup_list);
+	list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
+				 wakeup_list) {
 		if (device_can_wakeup(&dev->dev)) {
 			/* Button GPEs are supposed to be always enabled. */
 			acpi_enable_gpe(dev->wakeup.gpe_device,

include/acpi/acpixf.h

@@ -12,7 +12,7 @@
 
 /* Current ACPICA subsystem version in YYYYMMDD format */
 
-#define ACPI_CA_VERSION                 0x20200110
+#define ACPI_CA_VERSION                 0x20200214
 
 #include <acpi/acconfig.h>
 #include <acpi/actypes.h>

include/acpi/actbl1.h

@@ -862,7 +862,7 @@ enum acpi_erst_instructions {
 /* Command status return values */
 
 enum acpi_erst_command_status {
-	ACPI_ERST_SUCESS = 0,
+	ACPI_ERST_SUCCESS = 0,
 	ACPI_ERST_NO_SPACE = 1,
 	ACPI_ERST_NOT_AVAILABLE = 2,
 	ACPI_ERST_FAILURE = 3,

include/acpi/button.h

@@ -2,6 +2,10 @@
 #ifndef ACPI_BUTTON_H
 #define ACPI_BUTTON_H
 
+#define ACPI_BUTTON_HID_POWER	"PNP0C0C"
+#define ACPI_BUTTON_HID_LID	"PNP0C0D"
+#define ACPI_BUTTON_HID_SLEEP	"PNP0C0E"
+
 #if IS_ENABLED(CONFIG_ACPI_BUTTON)
 extern int acpi_lid_open(void);
 #else