lib: utils/i2c: Use kconfig for enabling/disabling drivers

We update i2c drivers makefile to use kconfig for enabling/disabling
drivers. To avoid compile errors, we also enable appropriate i2c
drivers for each platform.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Tested-by: Andrew Jones <ajones@ventanamicro.com>
Acked-by: Atish Patra <atishp@rivosinc.com>
Tested-by: Atish Patra <atishp@rivosinc.com>

lib/utils/Kconfig

@@ -2,6 +2,8 @@
 
 menu "Utils and Drivers Support"
 
+source "$(OPENSBI_SRC_DIR)/lib/utils/i2c/Kconfig"
+
 source "$(OPENSBI_SRC_DIR)/lib/utils/ipi/Kconfig"
 
 source "$(OPENSBI_SRC_DIR)/lib/utils/irqchip/Kconfig"

lib/utils/i2c/Kconfig

@@ -0,0 +1,22 @@
+# SPDX-License-Identifier: BSD-2-Clause
+
+menu "I2C Support"
+
+config FDT_I2C
+	bool "FDT based I2C drivers"
+	select I2C
+	default n
+
+if FDT_I2C
+
+config FDT_I2C_SIFIVE
+	bool "SiFive I2C FDT driver"
+	default n
+
+endif
+
+config I2C
+	bool "I2C support"
+	default n
+
+endmenu

lib/utils/i2c/objects.mk

@@ -7,10 +7,10 @@
 #   Nikita Shubin <n.shubin@yadro.com>
 #
 
-libsbiutils-objs-y += i2c/i2c.o
+libsbiutils-objs-$(CONFIG_I2C) += i2c/i2c.o
 
-libsbiutils-objs-y += i2c/fdt_i2c.o
-libsbiutils-objs-y += i2c/fdt_i2c_adapter_drivers.o
+libsbiutils-objs-$(CONFIG_FDT_I2C) += i2c/fdt_i2c.o
+libsbiutils-objs-$(CONFIG_FDT_I2C) += i2c/fdt_i2c_adapter_drivers.o
 
-carray-fdt_i2c_adapter_drivers-y += fdt_i2c_adapter_sifive
-libsbiutils-objs-y += i2c/fdt_i2c_sifive.o
+carray-fdt_i2c_adapter_drivers-$(CONFIG_FDT_I2C_SIFIVE) += fdt_i2c_adapter_sifive
+libsbiutils-objs-$(CONFIG_FDT_I2C_SIFIVE) += i2c/fdt_i2c_sifive.o

platform/generic/configs/defconfig

@@ -1,3 +1,5 @@
+CONFIG_FDT_I2C=y
+CONFIG_FDT_I2C_SIFIVE=y
 CONFIG_FDT_IPI=y
 CONFIG_FDT_IPI_MSWI=y
 CONFIG_FDT_IRQCHIP=y