diff options
| -rw-r--r-- | drivers/char/tpm/tpm_ppi.c | 45 |
1 files changed, 19 insertions, 26 deletions
diff --git a/drivers/char/tpm/tpm_ppi.c b/drivers/char/tpm/tpm_ppi.c index d542ac6d0ae0..117fab6daf39 100644 --- a/drivers/char/tpm/tpm_ppi.c +++ b/drivers/char/tpm/tpm_ppi.c @@ -23,39 +23,31 @@ static const u8 tpm_ppi_uuid[] = { 0x8D, 0x10, 0x08, 0x9D, 0x16, 0x53 }; -static char *tpm_device_name = "TPM"; 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; - status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); - if (ACPI_FAILURE(status)) + if (!acpi_check_dsm(handle, tpm_ppi_uuid, TPM_PPI_REVISION_ID, + 1 << TPM_PPI_FN_VERSION)) return AE_OK; - if (strstr(buffer.pointer, context) != NULL) { - union acpi_object *obj; - - /* 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; - status = AE_CTRL_TERMINATE; + /* 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); } - kfree(buffer.pointer); - return status; + *return_value = handle; + + return AE_CTRL_TERMINATE; } static inline union acpi_object * @@ -118,7 +110,8 @@ static ssize_t tpm_store_ppi_request(struct device *dev, * is updated with function index from SUBREQ to SUBREQ2 since PPI * version 1.1 */ - if (strcmp(tpm_ppi_version, "1.1") >= 0) + if (acpi_check_dsm(tpm_ppi_handle, tpm_ppi_uuid, TPM_PPI_REVISION_ID, + 1 << TPM_PPI_FN_SUBREQ2)) func = TPM_PPI_FN_SUBREQ2; /* @@ -272,7 +265,8 @@ static ssize_t show_ppi_operations(char *buf, u32 start, u32 end) "User not required", }; - if (strcmp(tpm_ppi_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; tmp.integer.type = ACPI_TYPE_INTEGER; @@ -334,8 +328,7 @@ 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, - tpm_device_name, &tpm_ppi_handle); + ppi_callback, NULL, NULL, &tpm_ppi_handle); if (tpm_ppi_handle == NULL) return -ENODEV; |
