kbuild: refactor some makefiles

[1] Move driver/core/, driver/input/ and drivers/input/ entries
    from the top Makefile to drivers/Makefile

[2] Remove the conditional by CONFIG_DM in drivers/core/Makefile
    because the whole drivers/core directory is already selected
    by CONFIG_DM in the upper level

[3] Likewise for CONFIG_DM_DEMO in drivers/demo/Makefile

[4] Simplify common/Makefile - both CONFIG_DDR_SPD and
    CONFIG_SPD_EEPROM are boolean macros so they can directly
    select objects

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Marek Vasut <marex@denx.de>

Makefile

@@ -613,11 +613,9 @@ libs-y += fs/
 libs-y += net/
 libs-y += disk/
 libs-y += drivers/
-libs-$(CONFIG_DM) += drivers/core/
 libs-y += drivers/dma/
 libs-y += drivers/gpio/
 libs-y += drivers/i2c/
-libs-y += drivers/input/
 libs-y += drivers/mmc/
 libs-y += drivers/mtd/
 libs-$(CONFIG_CMD_NAND) += drivers/mtd/nand/
@@ -649,7 +647,6 @@ libs-$(CONFIG_API) += api/
 libs-$(CONFIG_HAS_POST) += post/
 libs-y += test/
 libs-y += test/dm/
-libs-$(CONFIG_DM_DEMO) += drivers/demo/
 
 ifneq (,$(filter $(SOC), mx25 mx27 mx5 mx6 mx31 mx35 mxs vf610))
 libs-y += arch/$(ARCH)/imx-common/

common/Makefile

@@ -243,13 +243,8 @@ obj-y += cmd_nvedit.o
 #environment
 obj-y += env_common.o
 #others
-ifdef CONFIG_DDR_SPD
+obj-$(CONFIG_DDR_SPD) += ddr_spd.o
-SPD := y
+obj-$(CONFIG_SPD_EEPROM) += ddr_spd.o
-endif
-ifdef CONFIG_SPD_EEPROM
-SPD := y
-endif
-obj-$(SPD) += ddr_spd.o
 obj-$(CONFIG_HWCONFIG) += hwconfig.o
 obj-$(CONFIG_BOUNCE_BUFFER) += bouncebuf.o
 obj-y += console.o

drivers/Makefile

@@ -1,3 +1,5 @@
+obj-$(CONFIG_DM) += core/
+obj-$(CONFIG_DM_DEMO) += demo/
 obj-$(CONFIG_BIOSEMU) += bios_emulator/
 obj-y += block/
 obj-$(CONFIG_BOOTCOUNT_LIMIT) += bootcount/
@@ -16,3 +18,4 @@ obj-y += watchdog/
 obj-$(CONFIG_QE) += qe/
 obj-y += memory/
 obj-y += pwm/
+obj-y += input/

drivers/core/Makefile

@@ -4,4 +4,4 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-obj-$(CONFIG_DM)	:= device.o lists.o root.o uclass.o util.o
+obj-y := device.o lists.o root.o uclass.o util.o

drivers/demo/Makefile

@@ -4,6 +4,6 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-obj-$(CONFIG_DM_DEMO) += demo-uclass.o demo-pdata.o
+obj-y += demo-uclass.o demo-pdata.o
 obj-$(CONFIG_DM_DEMO_SIMPLE) += demo-simple.o
 obj-$(CONFIG_DM_DEMO_SHAPE) += demo-shape.o