Merge tag 'pm+acpi-3.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management updates from Rafael Wysocki:
 "As far as the number of commits goes, the top spot belongs to ACPI
  this time with cpufreq in the second position and a handful of PM
  core, PNP and cpuidle updates.  They are fixes and cleanups mostly, as
  usual, with a couple of new features in the mix.

  The most visible change is probably that we will create struct
  acpi_device objects (visible in sysfs) for all devices represented in
  the ACPI tables regardless of their status and there will be a new
  sysfs attribute under those objects allowing user space to check that
  status via _STA.

  Consequently, ACPI device eject or generally hot-removal will not
  delete those objects, unless the table containing the corresponding
  namespace nodes is unloaded, which is extremely rare.  Also ACPI
  container hotplug will be handled quite a bit differently and cpufreq
  will support CPU boost ("turbo") generically and not only in the
  acpi-cpufreq driver.

  Specifics:

   - ACPI core changes to make it create a struct acpi_device object for
     every device represented in the ACPI tables during all namespace
     scans regardless of the current status of that device.  In
     accordance with this, ACPI hotplug operations will not delete those
     objects, unless the underlying ACPI tables go away.

   - On top of the above, new sysfs attribute for ACPI device objects
     allowing user space to check device status by triggering the
     execution of _STA for its ACPI object.  From Srinivas Pandruvada.

   - ACPI core hotplug changes reducing code duplication, integrating
     the PCI root hotplug with the core and reworking container hotplug.

   - ACPI core simplifications making it use ACPI_COMPANION() in the
     code "glueing" ACPI device objects to "physical" devices.

   - ACPICA update to upstream version 20131218.  This adds support for
     the DBG2 and PCCT tables to ACPICA, fixes some bugs and improves
     debug facilities.  From Bob Moore, Lv Zheng and Betty Dall.

   - Init code change to carry out the early ACPI initialization
     earlier.  That should allow us to use ACPI during the timekeeping
     initialization and possibly to simplify the EFI initialization too.
     From Chun-Yi Lee.

   - Clenups of the inclusions of ACPI headers in many places all over
     from Lv Zheng and Rashika Kheria (work in progress).

   - New helper for ACPI _DSM execution and rework of the code in
     drivers that uses _DSM to execute it via the new helper.  From
     Jiang Liu.

   - New Win8 OSI blacklist entries from Takashi Iwai.

   - Assorted ACPI fixes and cleanups from Al Stone, Emil Goode, Hanjun
     Guo, Lan Tianyu, Masanari Iida, Oliver Neukum, Prarit Bhargava,
     Rashika Kheria, Tang Chen, Zhang Rui.

   - intel_pstate driver updates, including proper Baytrail support,
     from Dirk Brandewie and intel_pstate documentation from Ramkumar
     Ramachandra.

   - Generic CPU boost ("turbo") support for cpufreq from Lukasz
     Majewski.

   - powernow-k6 cpufreq driver fixes from Mikulas Patocka.

   - cpufreq core fixes and cleanups from Viresh Kumar, Jane Li, Mark
     Brown.

   - Assorted cpufreq drivers fixes and cleanups from Anson Huang, John
     Tobias, Paul Bolle, Paul Walmsley, Sachin Kamat, Shawn Guo, Viresh
     Kumar.

   - cpuidle cleanups from Bartlomiej Zolnierkiewicz.

   - Support for hibernation APM events from Bin Shi.

   - Hibernation fix to avoid bringing up nonboot CPUs with ACPI EC
     disabled during thaw transitions from Bjørn Mork.

   - PM core fixes and cleanups from Ben Dooks, Leonardo Potenza, Ulf
     Hansson.

   - PNP subsystem fixes and cleanups from Dmitry Torokhov, Levente
     Kurusa, Rashika Kheria.

   - New tool for profiling system suspend from Todd E Brandt and a
     cpupower tool cleanup from One Thousand Gnomes"

* tag 'pm+acpi-3.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (153 commits)
  thermal: exynos: boost: Automatic enable/disable of BOOST feature (at Exynos4412)
  cpufreq: exynos4x12: Change L0 driver data to CPUFREQ_BOOST_FREQ
  Documentation: cpufreq / boost: Update BOOST documentation
  cpufreq: exynos: Extend Exynos cpufreq driver to support boost
  cpufreq / boost: Kconfig: Support for software-managed BOOST
  acpi-cpufreq: Adjust the code to use the common boost attribute
  cpufreq: Add boost frequency support in core
  intel_pstate: Add trace point to report internal state.
  cpufreq: introduce cpufreq_generic_get() routine
  ARM: SA1100: Create dummy clk_get_rate() to avoid build failures
  cpufreq: stats: create sysfs entries when cpufreq_stats is a module
  cpufreq: stats: free table and remove sysfs entry in a single routine
  cpufreq: stats: remove hotplug notifiers
  cpufreq: stats: handle cpufreq_unregister_driver() and suspend/resume properly
  cpufreq: speedstep: remove unused speedstep_get_state
  platform: introduce OF style 'modalias' support for platform bus
  PM / tools: new tool for suspend/resume performance optimization
  ACPI: fix module autoloading for ACPI enumerated devices
  ACPI: add module autoloading support for ACPI enumerated devices
  ACPI: fix create_modalias() return value handling
  ...

2 files changed, 143 insertions, 265 deletions

diff --git a/drivers/char/tpm/tpm_acpi.c b/drivers/char/tpm/tpm_acpi.c
index 64420b3396a..b9a57fa4b71 100644
--- a/drivers/char/tpm/tpm_acpi.c
+++ b/drivers/char/tpm/tpm_acpi.c
@@ -23,7 +23,7 @@
 #include <linux/security.h>
 #include <linux/module.h>
 #include <linux/slab.h>
-#include <acpi/acpi.h>
+#include <linux/acpi.h>
 
 #include "tpm.h"
 #include "tpm_eventlog.h"
diff --git a/drivers/char/tpm/tpm_ppi.c b/drivers/char/tpm/tpm_ppi.c
index 2db4419831b..b3ea223585b 100644
--- a/drivers/char/tpm/tpm_ppi.c
+++ b/drivers/char/tpm/tpm_ppi.c
@@ -1,16 +1,6 @@
 #include <linux/acpi.h>
-#include <acpi/acpi_drivers.h>
 #include "tpm.h"
 
-static const u8 tpm_ppi_uuid[] = {
-	0xA6, 0xFA, 0xDD, 0x3D,
-	0x1B, 0x36,
-	0xB4, 0x4E,
-	0xA4, 0x24,
-	0x8D, 0x10, 0x08, 0x9D, 0x16, 0x53
-};
-static char *tpm_device_name = "TPM";
-
 #define TPM_PPI_REVISION_ID	1
 #define TPM_PPI_FN_VERSION	1
 #define TPM_PPI_FN_SUBREQ	2
@@ -24,250 +14,178 @@ static char *tpm_device_name = "TPM";
 #define PPI_VS_REQ_END		255
 #define PPI_VERSION_LEN		3
 
+static const u8 tpm_ppi_uuid[] = {
+	0xA6, 0xFA, 0xDD, 0x3D,
+	0x1B, 0x36,
+	0xB4, 0x4E,
+	0xA4, 0x24,
+	0x8D, 0x10, 0x08, 0x9D, 0x16, 0x53
+};
+
+static char tpm_ppi_version[PPI_VERSION_LEN + 1];
+static acpi_handle tpm_ppi_handle;
+
 static acpi_status ppi_callback(acpi_handle handle, u32 level, void *context,
 				void **return_value)
 {
-	acpi_status status = AE_OK;
-	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *obj;
 
-	if (ACPI_SUCCESS(acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer))) {
-		if (strstr(buffer.pointer, context) != NULL) {
-			*return_value = handle;
-			status = AE_CTRL_TERMINATE;
-		}
-		kfree(buffer.pointer);
+	if (!acpi_check_dsm(handle, tpm_ppi_uuid, TPM_PPI_REVISION_ID,
+			    1 << TPM_PPI_FN_VERSION))
+		return AE_OK;
+
+	/* Cache version string */
+	obj = acpi_evaluate_dsm_typed(handle, tpm_ppi_uuid,
+				      TPM_PPI_REVISION_ID, TPM_PPI_FN_VERSION,
+				      NULL, ACPI_TYPE_STRING);
+	if (obj) {
+		strlcpy(tpm_ppi_version, obj->string.pointer,
+			PPI_VERSION_LEN + 1);
+		ACPI_FREE(obj);
 	}
 
-	return status;
+	*return_value = handle;
+
+	return AE_CTRL_TERMINATE;
 }
 
-static inline void ppi_assign_params(union acpi_object params[4],
-				     u64 function_num)
+static inline union acpi_object *
+tpm_eval_dsm(int func, acpi_object_type type, union acpi_object *argv4)
 {
-	params[0].type = ACPI_TYPE_BUFFER;
-	params[0].buffer.length = sizeof(tpm_ppi_uuid);
-	params[0].buffer.pointer = (char *)tpm_ppi_uuid;
-	params[1].type = ACPI_TYPE_INTEGER;
-	params[1].integer.value = TPM_PPI_REVISION_ID;
-	params[2].type = ACPI_TYPE_INTEGER;
-	params[2].integer.value = function_num;
-	params[3].type = ACPI_TYPE_PACKAGE;
-	params[3].package.count = 0;
-	params[3].package.elements = NULL;
+	BUG_ON(!tpm_ppi_handle);
+	return acpi_evaluate_dsm_typed(tpm_ppi_handle, tpm_ppi_uuid,
+				       TPM_PPI_REVISION_ID, func, argv4, type);
 }
 
 static ssize_t tpm_show_ppi_version(struct device *dev,
 				    struct device_attribute *attr, char *buf)
 {
-	acpi_handle handle;
-	acpi_status status;
-	struct acpi_object_list input;
-	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
-	union acpi_object params[4];
-	union acpi_object *obj;
-
-	input.count = 4;
-	ppi_assign_params(params, TPM_PPI_FN_VERSION);
-	input.pointer = params;
-	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
-				     ACPI_UINT32_MAX, ppi_callback, NULL,
-				     tpm_device_name, &handle);
-	if (ACPI_FAILURE(status))
-		return -ENXIO;
-
-	status = acpi_evaluate_object_typed(handle, "_DSM", &input, &output,
-					 ACPI_TYPE_STRING);
-	if (ACPI_FAILURE(status))
-		return -ENOMEM;
-	obj = (union acpi_object *)output.pointer;
-	status = scnprintf(buf, PAGE_SIZE, "%s\n", obj->string.pointer);
-	kfree(output.pointer);
-	return status;
+	return scnprintf(buf, PAGE_SIZE, "%s\n", tpm_ppi_version);
 }
 
 static ssize_t tpm_show_ppi_request(struct device *dev,
 				    struct device_attribute *attr, char *buf)
 {
-	acpi_handle handle;
-	acpi_status status;
-	struct acpi_object_list input;
-	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
-	union acpi_object params[4];
-	union acpi_object *ret_obj;
-
-	input.count = 4;
-	ppi_assign_params(params, TPM_PPI_FN_GETREQ);
-	input.pointer = params;
-	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
-				     ACPI_UINT32_MAX, ppi_callback, NULL,
-				     tpm_device_name, &handle);
-	if (ACPI_FAILURE(status))
+	ssize_t size = -EINVAL;
+	union acpi_object *obj;
+
+	obj = tpm_eval_dsm(TPM_PPI_FN_GETREQ, ACPI_TYPE_PACKAGE, NULL);
+	if (!obj)
 		return -ENXIO;
 
-	status = acpi_evaluate_object_typed(handle, "_DSM", &input, &output,
-					    ACPI_TYPE_PACKAGE);
-	if (ACPI_FAILURE(status))
-		return -ENOMEM;
 	/*
 	 * output.pointer should be of package type, including two integers.
 	 * The first is function return code, 0 means success and 1 means
 	 * error. The second is pending TPM operation requested by the OS, 0
 	 * means none and >0 means operation value.
 	 */
-	ret_obj = ((union acpi_object *)output.pointer)->package.elements;
-	if (ret_obj->type == ACPI_TYPE_INTEGER) {
-		if (ret_obj->integer.value) {
-			status = -EFAULT;
-			goto cleanup;
-		}
-		ret_obj++;
-		if (ret_obj->type == ACPI_TYPE_INTEGER)
-			status = scnprintf(buf, PAGE_SIZE, "%llu\n",
-					   ret_obj->integer.value);
+	if (obj->package.count == 2 &&
+	    obj->package.elements[0].type == ACPI_TYPE_INTEGER &&
+	    obj->package.elements[1].type == ACPI_TYPE_INTEGER) {
+		if (obj->package.elements[0].integer.value)
+			size = -EFAULT;
 		else
-			status = -EINVAL;
-	} else {
-		status = -EINVAL;
+			size = scnprintf(buf, PAGE_SIZE, "%llu\n",
+				 obj->package.elements[1].integer.value);
 	}
-cleanup:
-	kfree(output.pointer);
-	return status;
+
+	ACPI_FREE(obj);
+
+	return size;
 }
 
 static ssize_t tpm_store_ppi_request(struct device *dev,
 				     struct device_attribute *attr,
 				     const char *buf, size_t count)
 {
-	char version[PPI_VERSION_LEN + 1];
-	acpi_handle handle;
-	acpi_status status;
-	struct acpi_object_list input;
-	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
-	union acpi_object params[4];
-	union acpi_object obj;
 	u32 req;
 	u64 ret;
+	int func = TPM_PPI_FN_SUBREQ;
+	union acpi_object *obj, tmp;
+	union acpi_object argv4 = ACPI_INIT_DSM_ARGV4(1, &tmp);
 
-	input.count = 4;
-	ppi_assign_params(params, TPM_PPI_FN_VERSION);
-	input.pointer = params;
-	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
-				     ACPI_UINT32_MAX, ppi_callback, NULL,
-				     tpm_device_name, &handle);
-	if (ACPI_FAILURE(status))
-		return -ENXIO;
-
-	status = acpi_evaluate_object_typed(handle, "_DSM", &input, &output,
-					    ACPI_TYPE_STRING);
-	if (ACPI_FAILURE(status))
-		return -ENOMEM;
-	strlcpy(version,
-		((union acpi_object *)output.pointer)->string.pointer,
-		PPI_VERSION_LEN + 1);
-	kfree(output.pointer);
-	output.length = ACPI_ALLOCATE_BUFFER;
-	output.pointer = NULL;
 	/*
 	 * the function to submit TPM operation request to pre-os environment
 	 * is updated with function index from SUBREQ to SUBREQ2 since PPI
 	 * version 1.1
 	 */
-	if (strcmp(version, "1.1") < 0)
-		params[2].integer.value = TPM_PPI_FN_SUBREQ;
-	else
-		params[2].integer.value = TPM_PPI_FN_SUBREQ2;
+	if (acpi_check_dsm(tpm_ppi_handle, tpm_ppi_uuid, TPM_PPI_REVISION_ID,
+			   1 << TPM_PPI_FN_SUBREQ2))
+		func = TPM_PPI_FN_SUBREQ2;
+
 	/*
 	 * PPI spec defines params[3].type as ACPI_TYPE_PACKAGE. Some BIOS
 	 * accept buffer/string/integer type, but some BIOS accept buffer/
 	 * string/package type. For PPI version 1.0 and 1.1, use buffer type
 	 * for compatibility, and use package type since 1.2 according to spec.
 	 */
-	if (strcmp(version, "1.2") < 0) {
-		params[3].type = ACPI_TYPE_BUFFER;
-		params[3].buffer.length = sizeof(req);
-		sscanf(buf, "%d", &req);
-		params[3].buffer.pointer = (char *)&req;
+	if (strcmp(tpm_ppi_version, "1.2") < 0) {
+		if (sscanf(buf, "%d", &req) != 1)
+			return -EINVAL;
+		argv4.type = ACPI_TYPE_BUFFER;
+		argv4.buffer.length = sizeof(req);
+		argv4.buffer.pointer = (u8 *)&req;
+	} else {
+		tmp.type = ACPI_TYPE_INTEGER;
+		if (sscanf(buf, "%llu", &tmp.integer.value) != 1)
+			return -EINVAL;
+	}
+
+	obj = tpm_eval_dsm(func, ACPI_TYPE_INTEGER, &argv4);
+	if (!obj) {
+		return -ENXIO;
 	} else {
-		params[3].package.count = 1;
-		obj.type = ACPI_TYPE_INTEGER;
-		sscanf(buf, "%llu", &obj.integer.value);
-		params[3].package.elements = &obj;
+		ret = obj->integer.value;
+		ACPI_FREE(obj);
 	}
 
-	status = acpi_evaluate_object_typed(handle, "_DSM", &input, &output,
-					    ACPI_TYPE_INTEGER);
-	if (ACPI_FAILURE(status))
-		return -ENOMEM;
-	ret = ((union acpi_object *)output.pointer)->integer.value;
 	if (ret == 0)
-		status = (acpi_status)count;
-	else if (ret == 1)
-		status = -EPERM;
-	else
-		status = -EFAULT;
-	kfree(output.pointer);
-	return status;
+		return (acpi_status)count;
+
+	return (ret == 1) ? -EPERM : -EFAULT;
 }
 
 static ssize_t tpm_show_ppi_transition_action(struct device *dev,
 					      struct device_attribute *attr,
 					      char *buf)
 {
-	char version[PPI_VERSION_LEN + 1];
-	acpi_handle handle;
-	acpi_status status;
-	struct acpi_object_list input;
-	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
-	union acpi_object params[4];
 	u32 ret;
-	char *info[] = {
+	acpi_status status;
+	union acpi_object *obj = NULL;
+	union acpi_object tmp = {
+		.buffer.type = ACPI_TYPE_BUFFER,
+		.buffer.length = 0,
+		.buffer.pointer = NULL
+	};
+
+	static char *info[] = {
 		"None",
 		"Shutdown",
 		"Reboot",
 		"OS Vendor-specific",
 		"Error",
 	};
-	input.count = 4;
-	ppi_assign_params(params, TPM_PPI_FN_VERSION);
-	input.pointer = params;
-	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
-				     ACPI_UINT32_MAX, ppi_callback, NULL,
-				     tpm_device_name, &handle);
-	if (ACPI_FAILURE(status))
-		return -ENXIO;
 
-	status = acpi_evaluate_object_typed(handle, "_DSM", &input, &output,
-					    ACPI_TYPE_STRING);
-	if (ACPI_FAILURE(status))
-		return -ENOMEM;
-	strlcpy(version,
-		((union acpi_object *)output.pointer)->string.pointer,
-		PPI_VERSION_LEN + 1);
 	/*
 	 * PPI spec defines params[3].type as empty package, but some platforms
 	 * (e.g. Capella with PPI 1.0) need integer/string/buffer type, so for
 	 * compatibility, define params[3].type as buffer, if PPI version < 1.2
 	 */
-	if (strcmp(version, "1.2") < 0) {
-		params[3].type = ACPI_TYPE_BUFFER;
-		params[3].buffer.length =  0;
-		params[3].buffer.pointer = NULL;
+	if (strcmp(tpm_ppi_version, "1.2") < 0)
+		obj = &tmp;
+	obj = tpm_eval_dsm(TPM_PPI_FN_GETACT, ACPI_TYPE_INTEGER, obj);
+	if (!obj) {
+		return -ENXIO;
+	} else {
+		ret = obj->integer.value;
+		ACPI_FREE(obj);
 	}
-	params[2].integer.value = TPM_PPI_FN_GETACT;
-	kfree(output.pointer);
-	output.length = ACPI_ALLOCATE_BUFFER;
-	output.pointer = NULL;
-	status = acpi_evaluate_object_typed(handle, "_DSM", &input, &output,
-					    ACPI_TYPE_INTEGER);
-	if (ACPI_FAILURE(status))
-		return -ENOMEM;
-	ret = ((union acpi_object *)output.pointer)->integer.value;
+
 	if (ret < ARRAY_SIZE(info) - 1)
 		status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret, info[ret]);
 	else
 		status = scnprintf(buf, PAGE_SIZE, "%d: %s\n", ret,
 				   info[ARRAY_SIZE(info)-1]);
-	kfree(output.pointer);
 	return status;
 }
 
@@ -275,27 +193,14 @@ static ssize_t tpm_show_ppi_response(struct device *dev,
 				     struct device_attribute *attr,
 				     char *buf)
 {
-	acpi_handle handle;
-	acpi_status status;
-	struct acpi_object_list input;
-	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
-	union acpi_object params[4];
-	union acpi_object *ret_obj;
-	u64 req;
-
-	input.count = 4;
-	ppi_assign_params(params, TPM_PPI_FN_GETRSP);
-	input.pointer = params;
-	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
-				     ACPI_UINT32_MAX, ppi_callback, NULL,
-				     tpm_device_name, &handle);
-	if (ACPI_FAILURE(status))
+	acpi_status status = -EINVAL;
+	union acpi_object *obj, *ret_obj;
+	u64 req, res;
+
+	obj = tpm_eval_dsm(TPM_PPI_FN_GETRSP, ACPI_TYPE_PACKAGE, NULL);
+	if (!obj)
 		return -ENXIO;
 
-	status = acpi_evaluate_object_typed(handle, "_DSM", &input, &output,
-					    ACPI_TYPE_PACKAGE);
-	if (ACPI_FAILURE(status))
-		return -ENOMEM;
 	/*
 	 * parameter output.pointer should be of package type, including
 	 * 3 integers. The first means function return code, the second means
@@ -303,115 +208,82 @@ static ssize_t tpm_show_ppi_response(struct device *dev,
 	 * the most recent TPM operation request. Only if the first is 0, and
 	 * the second integer is not 0, the response makes sense.
 	 */
-	ret_obj = ((union acpi_object *)output.pointer)->package.elements;
-	if (ret_obj->type != ACPI_TYPE_INTEGER) {
-		status = -EINVAL;
+	ret_obj = obj->package.elements;
+	if (obj->package.count < 3 ||
+	    ret_obj[0].type != ACPI_TYPE_INTEGER ||
+	    ret_obj[1].type != ACPI_TYPE_INTEGER ||
+	    ret_obj[2].type != ACPI_TYPE_INTEGER)
 		goto cleanup;
-	}
-	if (ret_obj->integer.value) {
+
+	if (ret_obj[0].integer.value) {
 		status = -EFAULT;
 		goto cleanup;
 	}
-	ret_obj++;
-	if (ret_obj->type != ACPI_TYPE_INTEGER) {
-		status = -EINVAL;
-		goto cleanup;
-	}
-	if (ret_obj->integer.value) {
-		req = ret_obj->integer.value;
-		ret_obj++;
-		if (ret_obj->type != ACPI_TYPE_INTEGER) {
-			status = -EINVAL;
-			goto cleanup;
-		}
-		if (ret_obj->integer.value == 0)
+
+	req = ret_obj[1].integer.value;
+	res = ret_obj[2].integer.value;
+	if (req) {
+		if (res == 0)
 			status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
 					   "0: Success");
-		else if (ret_obj->integer.value == 0xFFFFFFF0)
+		else if (res == 0xFFFFFFF0)
 			status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
 					   "0xFFFFFFF0: User Abort");
-		else if (ret_obj->integer.value == 0xFFFFFFF1)
+		else if (res == 0xFFFFFFF1)
 			status = scnprintf(buf, PAGE_SIZE, "%llu %s\n", req,
 					   "0xFFFFFFF1: BIOS Failure");
-		else if (ret_obj->integer.value >= 1 &&
-			 ret_obj->integer.value <= 0x00000FFF)
+		else if (res >= 1 && res <= 0x00000FFF)
 			status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",
-					   req, ret_obj->integer.value,
-					   "Corresponding TPM error");
+					   req, res, "Corresponding TPM error");
 		else
 			status = scnprintf(buf, PAGE_SIZE, "%llu %llu: %s\n",
-					   req, ret_obj->integer.value,
-					   "Error");
+					   req, res, "Error");
 	} else {
 		status = scnprintf(buf, PAGE_SIZE, "%llu: %s\n",
-				   ret_obj->integer.value, "No Recent Request");
+				   req, "No Recent Request");
 	}
+
 cleanup:
-	kfree(output.pointer);
+	ACPI_FREE(obj);
 	return status;
 }
 
 static ssize_t show_ppi_operations(char *buf, u32 start, u32 end)
 {
-	char *str = buf;
-	char version[PPI_VERSION_LEN + 1];
-	acpi_handle handle;
-	acpi_status status;
-	struct acpi_object_list input;
-	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
-	union acpi_object params[4];
-	union acpi_object obj;
 	int i;
 	u32 ret;
-	char *info[] = {
+	char *str = buf;
+	union acpi_object *obj, tmp;
+	union acpi_object argv = ACPI_INIT_DSM_ARGV4(1, &tmp);
+
+	static char *info[] = {
 		"Not implemented",
 		"BIOS only",
 		"Blocked for OS by BIOS",
 		"User required",
 		"User not required",
 	};
-	input.count = 4;
-	ppi_assign_params(params, TPM_PPI_FN_VERSION);
-	input.pointer = params;
-	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
-				     ACPI_UINT32_MAX, ppi_callback, NULL,
-				     tpm_device_name, &handle);
-	if (ACPI_FAILURE(status))
-		return -ENXIO;
 
-	status = acpi_evaluate_object_typed(handle, "_DSM", &input, &output,
-					 ACPI_TYPE_STRING);
-	if (ACPI_FAILURE(status))
-		return -ENOMEM;
-
-	strlcpy(version,
-		((union acpi_object *)output.pointer)->string.pointer,
-		PPI_VERSION_LEN + 1);
-	kfree(output.pointer);
-	output.length = ACPI_ALLOCATE_BUFFER;
-	output.pointer = NULL;
-	if (strcmp(version, "1.2") < 0)
+	if (!acpi_check_dsm(tpm_ppi_handle, tpm_ppi_uuid, TPM_PPI_REVISION_ID,
+			    1 << TPM_PPI_FN_GETOPR))
 		return -EPERM;
 
-	params[2].integer.value = TPM_PPI_FN_GETOPR;
-	params[3].package.count = 1;
-	obj.type = ACPI_TYPE_INTEGER;
-	params[3].package.elements = &obj;
+	tmp.integer.type = ACPI_TYPE_INTEGER;
 	for (i = start; i <= end; i++) {
-		obj.integer.value = i;
-		status = acpi_evaluate_object_typed(handle, "_DSM",
-			 &input, &output, ACPI_TYPE_INTEGER);
-		if (ACPI_FAILURE(status))
+		tmp.integer.value = i;
+		obj = tpm_eval_dsm(TPM_PPI_FN_GETOPR, ACPI_TYPE_INTEGER, &argv);
+		if (!obj) {
 			return -ENOMEM;
+		} else {
+			ret = obj->integer.value;
+			ACPI_FREE(obj);
+		}
 
-		ret = ((union acpi_object *)output.pointer)->integer.value;
 		if (ret > 0 && ret < ARRAY_SIZE(info))
 			str += scnprintf(str, PAGE_SIZE, "%d %d: %s\n",
 					 i, ret, info[ret]);
-		kfree(output.pointer);
-		output.length = ACPI_ALLOCATE_BUFFER;
-		output.pointer = NULL;
 	}
+
 	return str - buf;
 }
 
@@ -453,6 +325,12 @@ static struct attribute_group ppi_attr_grp = {
 
 int tpm_add_ppi(struct kobject *parent)
 {
+	/* Cache TPM ACPI handle and version string */
+	acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, ACPI_UINT32_MAX,
+			    ppi_callback, NULL, NULL, &tpm_ppi_handle);
+	if (tpm_ppi_handle == NULL)
+		return -ENODEV;
+
 	return sysfs_create_group(parent, &ppi_attr_grp);
 }