dsa: Hide core config options; make drivers select what they need

Commit 82167cb8c6b2f8166d5c7532e5ef4b5e0cc46a72 ('net: dsa/slave: Fix
compilation warnings') fixed one possible invalid configuration
(NET_DSA enabled with no trailer formats) but added others: drivers
can select NET_DSA without its dependencies being met.

It's not very useful to make either the DSA core or the tagging
formats manually selectable without a driver to use them, so:

1. Define a hidden HAVE_NET_DSA option and move the dependencies of
   NET_DSA to that.  While we're at it, drop the deprecated
   EXPERIMENTAL dependency.
2. Make NET_DSA and the drivers dependent on HAVE_NET_DSA.
3. Hide the tagging format options again.
4. Make drivers select both NET_DSA and the appropriate tagging format
   option.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 13 insertions, 17 deletions

diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig
index 0f5dc344ed92..f5eede1d6cb8 100644
--- a/net/dsa/Kconfig
+++ b/net/dsa/Kconfig
@@ -1,28 +1,24 @@
+config HAVE_NET_DSA
+        def_bool y
+        depends on NETDEVICES && !S390
+
+# Drivers must select NET_DSA and the appropriate tagging format
+
 config NET_DSA
         tristate
-        default n
-        depends on EXPERIMENTAL && NETDEVICES && !S390
+        depends on HAVE_NET_DSA
         select PHYLIB
-        ---help---
-          This allows you to use hardware switch chips that use
-          the Distributed Switch Architecture.
 
-
-menu "Distributed Switch Architecture support"
+if NET_DSA
 
 # tagging formats
 config NET_DSA_TAG_DSA
-        bool "Original DSA packet tagging format"
-        select NET_DSA
-        default n
+        bool
 
 config NET_DSA_TAG_EDSA
-        bool "Ethertype DSA packet tagging format"
-        select NET_DSA
-        default n
+        bool
 
 config NET_DSA_TAG_TRAILER
-        bool "Trailer DSA packet tagging format"
-        select NET_DSA
-        default n
-endmenu
+        bool
+
+endif