Merge tag 'pm+acpi-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI updates from Rafael Wysocki:
 "From the number of commits perspective, the biggest items are ACPICA
  and cpufreq changes with the latter taking the lead (over 50 commits).

  On the cpufreq front, there are many cleanups and minor fixes in the
  core and governors, driver updates etc.  We also have a new cpufreq
  driver for Mediatek MT8173 chips.

  ACPICA mostly updates its debug infrastructure and adds a number of
  fixes and cleanups for a good measure.

  The Operating Performance Points (OPP) framework is updated with new
  DT bindings and support for them among other things.

  We have a few updates of the generic power domains framework and a
  reorganization of the ACPI device enumeration code and bus type
  operations.

  And a lot of fixes and cleanups all over.

  Included is one branch from the MFD tree as it contains some
  PM-related driver core and ACPI PM changes a few other commits are
  based on.

  Specifics:

   - ACPICA update to upstream revision 20150818 including method
     tracing extensions to allow more in-depth AML debugging in the
     kernel and a number of assorted fixes and cleanups (Bob Moore, Lv
     Zheng, Markus Elfring).

   - ACPI sysfs code updates and a documentation update related to AML
     method tracing (Lv Zheng).

   - ACPI EC driver fix related to serialized evaluations of _Qxx
     methods and ACPI tools updates allowing the EC userspace tool to be
     built from the kernel source (Lv Zheng).

   - ACPI processor driver updates preparing it for future introduction
     of CPPC support and ACPI PCC mailbox driver updates (Ashwin
     Chaugule).

   - ACPI interrupts enumeration fix for a regression related to the
     handling of IRQ attribute conflicts between MADT and the ACPI
     namespace (Jiang Liu).

   - Fixes related to ACPI device PM (Mika Westerberg, Srinidhi
     Kasagar).

   - ACPI device registration code reorganization to separate the
     sysfs-related code and bus type operations from the rest (Rafael J
     Wysocki).

   - Assorted cleanups in the ACPI core (Jarkko Nikula, Mathias Krause,
     Andy Shevchenko, Rafael J Wysocki, Nicolas Iooss).

   - ACPI cpufreq driver and ia64 cpufreq driver fixes and cleanups (Pan
     Xinhui, Rafael J Wysocki).

   - cpufreq core cleanups on top of the previous changes allowing it to
     preseve its sysfs directories over system suspend/resume (Viresh
     Kumar, Rafael J Wysocki, Sebastian Andrzej Siewior).

   - cpufreq fixes and cleanups related to governors (Viresh Kumar).

   - cpufreq updates (core and the cpufreq-dt driver) related to the
     turbo/boost mode support (Viresh Kumar, Bartlomiej Zolnierkiewicz).

   - New DT bindings for Operating Performance Points (OPP), support for
     them in the OPP framework and in the cpufreq-dt driver plus related
     OPP framework fixes and cleanups (Viresh Kumar).

   - cpufreq powernv driver updates (Shilpasri G Bhat).

   - New cpufreq driver for Mediatek MT8173 (Pi-Cheng Chen).

   - Assorted cpufreq driver (speedstep-lib, sfi, integrator) cleanups
     and fixes (Abhilash Jindal, Andrzej Hajda, Cristian Ardelean).

   - intel_pstate driver updates including Skylake-S support, support
     for enabling HW P-states per CPU and an additional vendor bypass
     list entry (Kristen Carlson Accardi, Chen Yu, Ethan Zhao).

   - cpuidle core fixes related to the handling of coupled idle states
     (Xunlei Pang).

   - intel_idle driver updates including Skylake Client support and
     support for freeze-mode-specific idle states (Len Brown).

   - Driver core updates related to power management (Andy Shevchenko,
     Rafael J Wysocki).

   - Generic power domains framework fixes and cleanups (Jon Hunter,
     Geert Uytterhoeven, Rajendra Nayak, Ulf Hansson).

   - Device PM QoS framework update to allow the latency tolerance
     setting to be exposed to user space via sysfs (Mika Westerberg).

   - devfreq support for PPMUv2 in Exynos5433 and a fix for an incorrect
     exynos-ppmu DT binding (Chanwoo Choi, Javier Martinez Canillas).

   - System sleep support updates (Alan Stern, Len Brown, SungEun Kim).

   - rockchip-io AVS support updates (Heiko Stuebner).

   - PM core clocks support fixup (Colin Ian King).

   - Power capping RAPL driver update including support for Skylake H/S
     and Broadwell-H (Radivoje Jovanovic, Seiichi Ikarashi).

   - Generic device properties framework fixes related to the handling
     of static (driver-provided) property sets (Andy Shevchenko).

   - turbostat and cpupower updates (Len Brown, Shilpasri G Bhat,
     Shreyas B Prabhu)"

* tag 'pm+acpi-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (180 commits)
  cpufreq: speedstep-lib: Use monotonic clock
  cpufreq: powernv: Increase the verbosity of OCC console messages
  cpufreq: sfi: use kmemdup rather than duplicating its implementation
  cpufreq: drop !cpufreq_driver check from cpufreq_parse_governor()
  cpufreq: rename cpufreq_real_policy as cpufreq_user_policy
  cpufreq: remove redundant 'policy' field from user_policy
  cpufreq: remove redundant 'governor' field from user_policy
  cpufreq: update user_policy.* on success
  cpufreq: use memcpy() to copy policy
  cpufreq: remove redundant CPUFREQ_INCOMPATIBLE notifier event
  cpufreq: mediatek: Add MT8173 cpufreq driver
  dt-bindings: mediatek: Add MT8173 CPU DVFS clock bindings
  PM / Domains: Fix typo in description of genpd_dev_pm_detach()
  PM / Domains: Remove unusable governor dummies
  PM / Domains: Make pm_genpd_init() available to modules
  PM / domains: Align column headers and data in pm_genpd_summary output
  powercap / RAPL: disable the 2nd power limit properly
  tools: cpupower: Fix error when running cpupower monitor
  PM / OPP: Drop unlikely before IS_ERR(_OR_NULL)
  PM / OPP: Fix static checker warning (broken 64bit big endian systems)
  ...

1 files changed, 156 insertions, 119 deletions

diff --git a/drivers/acpi/acpica/nsnames.c b/drivers/acpi/acpica/nsnames.c
index d293d9748036..8934b4eddb73 100644
--- a/drivers/acpi/acpica/nsnames.c
+++ b/drivers/acpi/acpica/nsnames.c
@@ -51,73 +51,6 @@ ACPI_MODULE_NAME("nsnames")
 
 /*******************************************************************************
  *
- * FUNCTION:    acpi_ns_build_external_path
- *
- * PARAMETERS:  node            - NS node whose pathname is needed
- *              size            - Size of the pathname
- *              *name_buffer    - Where to return the pathname
- *
- * RETURN:      Status
- *              Places the pathname into the name_buffer, in external format
- *              (name segments separated by path separators)
- *
- * DESCRIPTION: Generate a full pathaname
- *
- ******************************************************************************/
-acpi_status
-acpi_ns_build_external_path(struct acpi_namespace_node *node,
-			    acpi_size size, char *name_buffer)
-{
-	acpi_size index;
-	struct acpi_namespace_node *parent_node;
-
-	ACPI_FUNCTION_ENTRY();
-
-	/* Special case for root */
-
-	index = size - 1;
-	if (index < ACPI_NAME_SIZE) {
-		name_buffer[0] = AML_ROOT_PREFIX;
-		name_buffer[1] = 0;
-		return (AE_OK);
-	}
-
-	/* Store terminator byte, then build name backwards */
-
-	parent_node = node;
-	name_buffer[index] = 0;
-
-	while ((index > ACPI_NAME_SIZE) && (parent_node != acpi_gbl_root_node)) {
-		index -= ACPI_NAME_SIZE;
-
-		/* Put the name into the buffer */
-
-		ACPI_MOVE_32_TO_32((name_buffer + index), &parent_node->name);
-		parent_node = parent_node->parent;
-
-		/* Prefix name with the path separator */
-
-		index--;
-		name_buffer[index] = ACPI_PATH_SEPARATOR;
-	}
-
-	/* Overwrite final separator with the root prefix character */
-
-	name_buffer[index] = AML_ROOT_PREFIX;
-
-	if (index != 0) {
-		ACPI_ERROR((AE_INFO,
-			    "Could not construct external pathname; index=%u, size=%u, Path=%s",
-			    (u32) index, (u32) size, &name_buffer[size]));
-
-		return (AE_BAD_PARAMETER);
-	}
-
-	return (AE_OK);
-}
-
-/*******************************************************************************
- *
  * FUNCTION:    acpi_ns_get_external_pathname
  *
  * PARAMETERS:  node            - Namespace node whose pathname is needed
@@ -130,37 +63,13 @@ acpi_ns_build_external_path(struct acpi_namespace_node *node,
  *              for error and debug statements.
  *
  ******************************************************************************/
-
 char *acpi_ns_get_external_pathname(struct acpi_namespace_node *node)
 {
-	acpi_status status;
 	char *name_buffer;
-	acpi_size size;
 
 	ACPI_FUNCTION_TRACE_PTR(ns_get_external_pathname, node);
 
-	/* Calculate required buffer size based on depth below root */
-
-	size = acpi_ns_get_pathname_length(node);
-	if (!size) {
-		return_PTR(NULL);
-	}
-
-	/* Allocate a buffer to be returned to caller */
-
-	name_buffer = ACPI_ALLOCATE_ZEROED(size);
-	if (!name_buffer) {
-		ACPI_ERROR((AE_INFO, "Could not allocate %u bytes", (u32)size));
-		return_PTR(NULL);
-	}
-
-	/* Build the path in the allocated buffer */
-
-	status = acpi_ns_build_external_path(node, size, name_buffer);
-	if (ACPI_FAILURE(status)) {
-		ACPI_FREE(name_buffer);
-		return_PTR(NULL);
-	}
+	name_buffer = acpi_ns_get_normalized_pathname(node, FALSE);
 
 	return_PTR(name_buffer);
 }
@@ -180,33 +89,12 @@ char *acpi_ns_get_external_pathname(struct acpi_namespace_node *node)
 acpi_size acpi_ns_get_pathname_length(struct acpi_namespace_node *node)
 {
 	acpi_size size;
-	struct acpi_namespace_node *next_node;
 
 	ACPI_FUNCTION_ENTRY();
 
-	/*
-	 * Compute length of pathname as 5 * number of name segments.
-	 * Go back up the parent tree to the root
-	 */
-	size = 0;
-	next_node = node;
+	size = acpi_ns_build_normalized_path(node, NULL, 0, FALSE);
 
-	while (next_node && (next_node != acpi_gbl_root_node)) {
-		if (ACPI_GET_DESCRIPTOR_TYPE(next_node) != ACPI_DESC_TYPE_NAMED) {
-			ACPI_ERROR((AE_INFO,
-				    "Invalid Namespace Node (%p) while traversing namespace",
-				    next_node));
-			return (0);
-		}
-		size += ACPI_PATH_SEGMENT_LENGTH;
-		next_node = next_node->parent;
-	}
-
-	if (!size) {
-		size = 1;	/* Root node case */
-	}
-
-	return (size + 1);	/* +1 for null string terminator */
+	return (size);
 }
 
 /*******************************************************************************
@@ -216,6 +104,8 @@ acpi_size acpi_ns_get_pathname_length(struct acpi_namespace_node *node)
  * PARAMETERS:  target_handle           - Handle of named object whose name is
  *                                        to be found
  *              buffer                  - Where the pathname is returned
+ *              no_trailing             - Remove trailing '_' for each name
+ *                                        segment
  *
  * RETURN:      Status, Buffer is filled with pathname if status is AE_OK
  *
@@ -225,7 +115,7 @@ acpi_size acpi_ns_get_pathname_length(struct acpi_namespace_node *node)
 
 acpi_status
 acpi_ns_handle_to_pathname(acpi_handle target_handle,
-			   struct acpi_buffer * buffer)
+			   struct acpi_buffer * buffer, u8 no_trailing)
 {
 	acpi_status status;
 	struct acpi_namespace_node *node;
@@ -240,7 +130,8 @@ acpi_ns_handle_to_pathname(acpi_handle target_handle,
 
 	/* Determine size required for the caller buffer */
 
-	required_size = acpi_ns_get_pathname_length(node);
+	required_size =
+	    acpi_ns_build_normalized_path(node, NULL, 0, no_trailing);
 	if (!required_size) {
 		return_ACPI_STATUS(AE_BAD_PARAMETER);
 	}
@@ -254,8 +145,8 @@ acpi_ns_handle_to_pathname(acpi_handle target_handle,
 
 	/* Build the path in the caller buffer */
 
-	status =
-	    acpi_ns_build_external_path(node, required_size, buffer->pointer);
+	(void)acpi_ns_build_normalized_path(node, buffer->pointer,
+					    required_size, no_trailing);
 	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
 	}
@@ -264,3 +155,149 @@ acpi_ns_handle_to_pathname(acpi_handle target_handle,
 			  (char *)buffer->pointer, (u32) required_size));
 	return_ACPI_STATUS(AE_OK);
 }
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_build_normalized_path
+ *
+ * PARAMETERS:  node        - Namespace node
+ *              full_path   - Where the path name is returned
+ *              path_size   - Size of returned path name buffer
+ *              no_trailing - Remove trailing '_' from each name segment
+ *
+ * RETURN:      Return 1 if the AML path is empty, otherwise returning (length
+ *              of pathname + 1) which means the 'FullPath' contains a trailing
+ *              null.
+ *
+ * DESCRIPTION: Build and return a full namespace pathname.
+ *              Note that if the size of 'FullPath' isn't large enough to
+ *              contain the namespace node's path name, the actual required
+ *              buffer length is returned, and it should be greater than
+ *              'PathSize'. So callers are able to check the returning value
+ *              to determine the buffer size of 'FullPath'.
+ *
+ ******************************************************************************/
+
+u32
+acpi_ns_build_normalized_path(struct acpi_namespace_node *node,
+			      char *full_path, u32 path_size, u8 no_trailing)
+{
+	u32 length = 0, i;
+	char name[ACPI_NAME_SIZE];
+	u8 do_no_trailing;
+	char c, *left, *right;
+	struct acpi_namespace_node *next_node;
+
+	ACPI_FUNCTION_TRACE_PTR(ns_build_normalized_path, node);
+
+#define ACPI_PATH_PUT8(path, size, byte, length)    \
+	do {                                            \
+		if ((length) < (size))                      \
+		{                                           \
+			(path)[(length)] = (byte);              \
+		}                                           \
+		(length)++;                                 \
+	} while (0)
+
+	/*
+	 * Make sure the path_size is correct, so that we don't need to
+	 * validate both full_path and path_size.
+	 */
+	if (!full_path) {
+		path_size = 0;
+	}
+
+	if (!node) {
+		goto build_trailing_null;
+	}
+
+	next_node = node;
+	while (next_node && next_node != acpi_gbl_root_node) {
+		if (next_node != node) {
+			ACPI_PATH_PUT8(full_path, path_size,
+				       AML_DUAL_NAME_PREFIX, length);
+		}
+		ACPI_MOVE_32_TO_32(name, &next_node->name);
+		do_no_trailing = no_trailing;
+		for (i = 0; i < 4; i++) {
+			c = name[4 - i - 1];
+			if (do_no_trailing && c != '_') {
+				do_no_trailing = FALSE;
+			}
+			if (!do_no_trailing) {
+				ACPI_PATH_PUT8(full_path, path_size, c, length);
+			}
+		}
+		next_node = next_node->parent;
+	}
+	ACPI_PATH_PUT8(full_path, path_size, AML_ROOT_PREFIX, length);
+
+	/* Reverse the path string */
+
+	if (length <= path_size) {
+		left = full_path;
+		right = full_path + length - 1;
+		while (left < right) {
+			c = *left;
+			*left++ = *right;
+			*right-- = c;
+		}
+	}
+
+	/* Append the trailing null */
+
+build_trailing_null:
+	ACPI_PATH_PUT8(full_path, path_size, '\0', length);
+
+#undef ACPI_PATH_PUT8
+
+	return_UINT32(length);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_get_normalized_pathname
+ *
+ * PARAMETERS:  node            - Namespace node whose pathname is needed
+ *              no_trailing     - Remove trailing '_' from each name segment
+ *
+ * RETURN:      Pointer to storage containing the fully qualified name of
+ *              the node, In external format (name segments separated by path
+ *              separators.)
+ *
+ * DESCRIPTION: Used to obtain the full pathname to a namespace node, usually
+ *              for error and debug statements. All trailing '_' will be
+ *              removed from the full pathname if 'NoTrailing' is specified..
+ *
+ ******************************************************************************/
+
+char *acpi_ns_get_normalized_pathname(struct acpi_namespace_node *node,
+				      u8 no_trailing)
+{
+	char *name_buffer;
+	acpi_size size;
+
+	ACPI_FUNCTION_TRACE_PTR(ns_get_normalized_pathname, node);
+
+	/* Calculate required buffer size based on depth below root */
+
+	size = acpi_ns_build_normalized_path(node, NULL, 0, no_trailing);
+	if (!size) {
+		return_PTR(NULL);
+	}
+
+	/* Allocate a buffer to be returned to caller */
+
+	name_buffer = ACPI_ALLOCATE_ZEROED(size);
+	if (!name_buffer) {
+		ACPI_ERROR((AE_INFO, "Could not allocate %u bytes", (u32)size));
+		return_PTR(NULL);
+	}
+
+	/* Build the path in the allocated buffer */
+
+	(void)acpi_ns_build_normalized_path(node, name_buffer, size,
+					    no_trailing);
+
+	return_PTR(name_buffer);
+}