driver: add PPI support in tpm driver
The Physical Presence Interface enables the OS and the BIOS to cooperate and
provides a simple and straightforward platform user experience for
administering the TPM without sacrificing security.
V2: separate the patch out in a separate source file,
add #ifdef CONFIG_ACPI so it compiles out on ppc,
use standard error instead of ACPI error as return code of show/store fns.
V3: move #ifdef CONFIG_ACPI from .c file to .h file.
V4: move tpm_ppi code from tpm module to tpm_bios module.
V5: modify sys_add_ppi() so that ppi_attr_grp doesn't need to be exported
Signed-off-by: Xiaoyan Zhang <xiaoyan.zhang@intel.com>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index f1af738..02c266a 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -327,3 +327,12 @@
extern int tpm_pm_resume(struct device *);
extern int wait_for_tpm_stat(struct tpm_chip *, u8, unsigned long,
wait_queue_head_t *);
+
+#ifdef CONFIG_ACPI
+extern ssize_t sys_add_ppi(struct kobject *parent);
+#else
+static inline ssize_t sys_add_ppi(struct kobject *parent)
+{
+ return 0;
+}
+#endif