[PATCH] net: can: fix build dependency

[Arnd Bergmann <arnd@kernel.org>]

From: Arnd Bergmann <arnd@arndb.de>

A recent bugfix introduced a new problem with Kconfig dependencies:

WARNING: unmet direct dependencies detected for CAN_DEV
  Depends on [n]: NETDEVICES [=n] && CAN [=m]
  Selected by [m]:
  - CAN [=m] && NET [=y]

Since the CAN core code now links into the CAN device code, that
particular function needs to be available, though the rest of it
does not.

Revert the incomplete fix and instead use Makefile logic to avoid
the link failure.

Fixes: cb2dc6d2869a ("can: Kconfig: select CAN driver infrastructure by default")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/net/can/Kconfig      | 4 ++--
 drivers/net/can/Makefile     | 2 +-
 drivers/net/can/dev/Makefile | 5 ++---
 net/can/Kconfig              | 1 -
 4 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig
index e15e320db476..bc074218d0ee 100644
--- a/drivers/net/can/Kconfig
+++ b/drivers/net/can/Kconfig
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
 menuconfig CAN_DEV
-	tristate "CAN Device Drivers"
+	bool "CAN Device Drivers"
 	default y
 	depends on CAN
 	help
@@ -20,7 +20,7 @@ menuconfig CAN_DEV
 	  To compile as a module, choose M here: the module will be called
 	  can-dev.
 
-if CAN_DEV
+if CAN_DEV && CAN
 
 config CAN_VCAN
 	tristate "Virtual Local CAN Interface (vcan)"
diff --git a/drivers/net/can/Makefile b/drivers/net/can/Makefile
index d7bc10a6b8ea..37e2f1a2faec 100644
--- a/drivers/net/can/Makefile
+++ b/drivers/net/can/Makefile
@@ -7,7 +7,7 @@ obj-$(CONFIG_CAN_VCAN)		+= vcan.o
 obj-$(CONFIG_CAN_VXCAN)		+= vxcan.o
 obj-$(CONFIG_CAN_SLCAN)		+= slcan/
 
-obj-y				+= dev/
+obj-$(CONFIG_CAN_DEV)		+= dev/
 obj-y				+= esd/
 obj-y				+= rcar/
 obj-y				+= rockchip/
diff --git a/drivers/net/can/dev/Makefile b/drivers/net/can/dev/Makefile
index 633687d6b6c0..64226acf0f3d 100644
--- a/drivers/net/can/dev/Makefile
+++ b/drivers/net/can/dev/Makefile
@@ -1,9 +1,8 @@
 # SPDX-License-Identifier: GPL-2.0
 
-obj-$(CONFIG_CAN_DEV) += can-dev.o
-
-can-dev-y += skb.o
+obj-$(CONFIG_CAN) += can-dev.o
 
+can-dev-$(CONFIG_CAN_DEV) += skb.o
 can-dev-$(CONFIG_CAN_CALC_BITTIMING) += calc_bittiming.o
 can-dev-$(CONFIG_CAN_NETLINK) += bittiming.o
 can-dev-$(CONFIG_CAN_NETLINK) += dev.o
diff --git a/net/can/Kconfig b/net/can/Kconfig
index e4ccf731a24c..af64a6f76458 100644
--- a/net/can/Kconfig
+++ b/net/can/Kconfig
@@ -5,7 +5,6 @@
 
 menuconfig CAN
 	tristate "CAN bus subsystem support"
-	select CAN_DEV
 	help
 	  Controller Area Network (CAN) is a slow (up to 1Mbit/s) serial
 	  communications protocol. Development of the CAN bus started in
-- 
2.39.5