libata: make PMP support optional
Make PMP support optional by adding CONFIG_SATA_PMP and leaving out
libata-pmp.c if it isn't set. PMP helpers return constant values if
PMP support is not enabled and PMP declarations alias non-PMP
counterparts. This makes the compiler to leave out PMP related part
out and LLDs to use non-PMP counterparts automatically.
Signed-off-by: Tejun Heo <htejun@gmail.com>
diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
index e6e41b2..1fbc2aa 100644
--- a/drivers/ata/Makefile
+++ b/drivers/ata/Makefile
@@ -78,6 +78,7 @@
# Should be last libata driver
obj-$(CONFIG_PATA_LEGACY) += pata_legacy.o
-libata-objs := libata-core.o libata-scsi.o libata-eh.o libata-pmp.o
+libata-objs := libata-core.o libata-scsi.o libata-eh.o
libata-$(CONFIG_ATA_SFF) += libata-sff.o
+libata-$(CONFIG_SATA_PMP) += libata-pmp.o
libata-$(CONFIG_ATA_ACPI) += libata-acpi.o