tpm/tpm_tis: Split tpm_tis driver into a core and TCG TIS compliant phy

To avoid code duplication between the old tpm_tis and the new and future
native tcg tis driver(ie: spi, i2c...), the tpm_tis driver was reworked,
so that all common logic is extracted and can be reused from all drivers.

The core methods can also be used from other TIS like drivers.

itpm workaround is now managed with a specific tis flag
TPM_TIS_ITPM_POSSIBLE.

This commit is based on the initial work by Peter Huewe.

Signed-off-by: Peter Huewe <peter.huewe@infineon.com>
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

drivers/char/tpm/Kconfig

@@ -24,9 +24,16 @@ menuconfig TCG_TPM
 
 if TCG_TPM
 
+config TCG_TIS_CORE
+	tristate
+	---help---
+	TCG TIS TPM core driver. It implements the TPM TCG TIS logic and hooks
+	into the TPM kernel APIs. Physical layers will register against it.
+
 config TCG_TIS
 	tristate "TPM Interface Specification 1.2 Interface / TPM 2.0 FIFO Interface"
 	depends on X86
+	select TCG_TIS_CORE
 	---help---
 	  If you have a TPM security chip that is compliant with the
 	  TCG TIS 1.2 TPM specification (TPM1.2) or the TCG PTP FIFO

drivers/char/tpm/Makefile

@@ -12,6 +12,7 @@ ifdef CONFIG_TCG_IBMVTPM
 	tpm-y += tpm_eventlog.o tpm_of.o
 endif
 endif
+obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o
 obj-$(CONFIG_TCG_TIS) += tpm_tis.o
 obj-$(CONFIG_TCG_TIS_I2C_ATMEL) += tpm_i2c_atmel.o
 obj-$(CONFIG_TCG_TIS_I2C_INFINEON) += tpm_i2c_infineon.o