tpm: fix raciness of PPI interface lookup
Traversal of the ACPI device tree was not done right. PPI interface
should be looked up only from the ACPI device that is the platform
device for the TPM. This could cause problems with systems with
two TPM chips such as 4th gen Intel systems.
In addition, added the missing license and copyright platter to
the tpm_ppi.c.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Tested-by: Scot Doyle <lkml14@scotdoyle.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
diff --git a/drivers/char/tpm/tpm_ppi.c b/drivers/char/tpm/tpm_ppi.c
index 61dcc80..af48c56 100644
--- a/drivers/char/tpm/tpm_ppi.c
+++ b/drivers/char/tpm/tpm_ppi.c
@@ -1,3 +1,22 @@
+/*
+ * Copyright (C) 2012-2014 Intel Corporation
+ *
+ * Authors:
+ * Xiaoyan Zhang <xiaoyan.zhang@intel.com>
+ * Jiang Liu <jiang.liu@linux.intel.com>
+ * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
+ *
+ * Maintained by: <tpmdd-devel@lists.sourceforge.net>
+ *
+ * This file contains implementation of the sysfs interface for PPI.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ */
+
+
#include <linux/acpi.h>
#include "tpm.h"
@@ -12,7 +31,6 @@
#define PPI_TPM_REQ_MAX 22
#define PPI_VS_REQ_START 128
#define PPI_VS_REQ_END 255
-#define PPI_VERSION_LEN 3
static const u8 tpm_ppi_uuid[] = {
0xA6, 0xFA, 0xDD, 0x3D,
@@ -22,45 +40,22 @@
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)
-{
- union acpi_object *obj;
-
- 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_value = handle;
-
- return AE_CTRL_TERMINATE;
-}
-
static inline union acpi_object *
-tpm_eval_dsm(int func, acpi_object_type type, union acpi_object *argv4)
+tpm_eval_dsm(acpi_handle ppi_handle, int func, acpi_object_type type,
+ union acpi_object *argv4)
{
- BUG_ON(!tpm_ppi_handle);
- return acpi_evaluate_dsm_typed(tpm_ppi_handle, tpm_ppi_uuid,
- TPM_PPI_REVISION_ID, func, argv4, type);
+ BUG_ON(!ppi_handle);
+ return acpi_evaluate_dsm_typed(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)
{
- return scnprintf(buf, PAGE_SIZE, "%s\n", tpm_ppi_version);
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%s\n", chip->ppi_version);
}
static ssize_t tpm_show_ppi_request(struct device *dev,
@@ -68,8 +63,10 @@
{
ssize_t size = -EINVAL;
union acpi_object *obj;
+ struct tpm_chip *chip = dev_get_drvdata(dev);
- obj = tpm_eval_dsm(TPM_PPI_FN_GETREQ, ACPI_TYPE_PACKAGE, NULL);
+ obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETREQ,
+ ACPI_TYPE_PACKAGE, NULL);
if (!obj)
return -ENXIO;
@@ -103,14 +100,15 @@
int func = TPM_PPI_FN_SUBREQ;
union acpi_object *obj, tmp;
union acpi_object argv4 = ACPI_INIT_DSM_ARGV4(1, &tmp);
+ struct tpm_chip *chip = dev_get_drvdata(dev);
/*
* 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 (acpi_check_dsm(tpm_ppi_handle, tpm_ppi_uuid, TPM_PPI_REVISION_ID,
- 1 << TPM_PPI_FN_SUBREQ2))
+ if (acpi_check_dsm(chip->acpi_dev_handle, tpm_ppi_uuid,
+ TPM_PPI_REVISION_ID, 1 << TPM_PPI_FN_SUBREQ2))
func = TPM_PPI_FN_SUBREQ2;
/*
@@ -119,7 +117,7 @@
* 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(tpm_ppi_version, "1.2") < 0) {
+ if (strcmp(chip->ppi_version, "1.2") < 0) {
if (sscanf(buf, "%d", &req) != 1)
return -EINVAL;
argv4.type = ACPI_TYPE_BUFFER;
@@ -131,7 +129,8 @@
return -EINVAL;
}
- obj = tpm_eval_dsm(func, ACPI_TYPE_INTEGER, &argv4);
+ obj = tpm_eval_dsm(chip->acpi_dev_handle, func, ACPI_TYPE_INTEGER,
+ &argv4);
if (!obj) {
return -ENXIO;
} else {
@@ -157,6 +156,7 @@
.buffer.length = 0,
.buffer.pointer = NULL
};
+ struct tpm_chip *chip = dev_get_drvdata(dev);
static char *info[] = {
"None",
@@ -171,9 +171,10 @@
* (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(tpm_ppi_version, "1.2") < 0)
+ if (strcmp(chip->ppi_version, "1.2") < 0)
obj = &tmp;
- obj = tpm_eval_dsm(TPM_PPI_FN_GETACT, ACPI_TYPE_INTEGER, obj);
+ obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETACT,
+ ACPI_TYPE_INTEGER, obj);
if (!obj) {
return -ENXIO;
} else {
@@ -196,8 +197,10 @@
acpi_status status = -EINVAL;
union acpi_object *obj, *ret_obj;
u64 req, res;
+ struct tpm_chip *chip = dev_get_drvdata(dev);
- obj = tpm_eval_dsm(TPM_PPI_FN_GETRSP, ACPI_TYPE_PACKAGE, NULL);
+ obj = tpm_eval_dsm(chip->acpi_dev_handle, TPM_PPI_FN_GETRSP,
+ ACPI_TYPE_PACKAGE, NULL);
if (!obj)
return -ENXIO;
@@ -248,7 +251,8 @@
return status;
}
-static ssize_t show_ppi_operations(char *buf, u32 start, u32 end)
+static ssize_t show_ppi_operations(acpi_handle dev_handle, char *buf, u32 start,
+ u32 end)
{
int i;
u32 ret;
@@ -264,14 +268,15 @@
"User not required",
};
- if (!acpi_check_dsm(tpm_ppi_handle, tpm_ppi_uuid, TPM_PPI_REVISION_ID,
+ if (!acpi_check_dsm(dev_handle, tpm_ppi_uuid, TPM_PPI_REVISION_ID,
1 << TPM_PPI_FN_GETOPR))
return -EPERM;
tmp.integer.type = ACPI_TYPE_INTEGER;
for (i = start; i <= end; i++) {
tmp.integer.value = i;
- obj = tpm_eval_dsm(TPM_PPI_FN_GETOPR, ACPI_TYPE_INTEGER, &argv);
+ obj = tpm_eval_dsm(dev_handle, TPM_PPI_FN_GETOPR,
+ ACPI_TYPE_INTEGER, &argv);
if (!obj) {
return -ENOMEM;
} else {
@@ -291,14 +296,20 @@
struct device_attribute *attr,
char *buf)
{
- return show_ppi_operations(buf, 0, PPI_TPM_REQ_MAX);
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+
+ return show_ppi_operations(chip->acpi_dev_handle, buf, 0,
+ PPI_TPM_REQ_MAX);
}
static ssize_t tpm_show_ppi_vs_operations(struct device *dev,
struct device_attribute *attr,
char *buf)
{
- return show_ppi_operations(buf, PPI_VS_REQ_START, PPI_VS_REQ_END);
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+
+ return show_ppi_operations(chip->acpi_dev_handle, buf, PPI_VS_REQ_START,
+ PPI_VS_REQ_END);
}
static DEVICE_ATTR(version, S_IRUGO, tpm_show_ppi_version, NULL);
@@ -323,16 +334,38 @@
.attrs = ppi_attrs
};
-int tpm_add_ppi(struct kobject *parent)
+int tpm_add_ppi(struct tpm_chip *chip)
{
- /* 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);
- return tpm_ppi_handle ? sysfs_create_group(parent, &ppi_attr_grp) : 0;
+ union acpi_object *obj;
+ int rc;
+
+ if (!chip->acpi_dev_handle)
+ return 0;
+
+ if (!acpi_check_dsm(chip->acpi_dev_handle, tpm_ppi_uuid,
+ TPM_PPI_REVISION_ID, 1 << TPM_PPI_FN_VERSION))
+ return 0;
+
+ /* Cache PPI version string. */
+ obj = acpi_evaluate_dsm_typed(chip->acpi_dev_handle, tpm_ppi_uuid,
+ TPM_PPI_REVISION_ID, TPM_PPI_FN_VERSION,
+ NULL, ACPI_TYPE_STRING);
+ if (obj) {
+ strlcpy(chip->ppi_version, obj->string.pointer,
+ sizeof(chip->ppi_version));
+ ACPI_FREE(obj);
+ }
+
+ rc = sysfs_create_group(&chip->dev->kobj, &ppi_attr_grp);
+
+ if (!rc)
+ chip->flags |= TPM_CHIP_FLAG_PPI;
+
+ return rc;
}
-void tpm_remove_ppi(struct kobject *parent)
+void tpm_remove_ppi(struct tpm_chip *chip)
{
- if (tpm_ppi_handle)
- sysfs_remove_group(parent, &ppi_attr_grp);
+ if (chip->flags & TPM_CHIP_FLAG_PPI)
+ sysfs_remove_group(&chip->dev->kobj, &ppi_attr_grp);
}