firewire: add Kconfig help on building both stacks

Alas that won't work so good, because nobody reads help texts.

I thought about adding some crude multiple choice selection (build the
old stack, build the new stack, build both stacks).  It's possible, but
it would introduce awkward dummy config variables.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

drivers/firewire/Kconfig

@@ -4,27 +4,44 @@ comment "An alternative FireWire stack is available with EXPERIMENTAL=y"
 	depends on EXPERIMENTAL=n
 
 config FIREWIRE
-	tristate "IEEE 1394 (FireWire) support (JUJU alternative stack, experimental)"
+	tristate "IEEE 1394 (FireWire) support - alternative stack, EXPERIMENTAL"
 	depends on EXPERIMENTAL
 	select CRC_ITU_T
 	help
-	  IEEE 1394 describes a high performance serial bus, which is also
+	  This is the "Juju" FireWire stack, a new alternative implementation
-	  known as FireWire(tm) or i.Link(tm) and is used for connecting all
-	  sorts of devices (most notably digital video cameras) to your
-	  computer.
-
-	  If you have FireWire hardware and want to use it, say Y here.  This
-	  is the core support only, you will also need to select a driver for
-	  your IEEE 1394 adapter.
-
-	  To compile this driver as a module, say M here: the module will be
-	  called firewire-core.
-
-	  This is the "JUJU" FireWire stack, an alternative implementation
 	  designed for robustness and simplicity.  You can build either this
 	  stack, or the classic stack (the ieee1394 driver, ohci1394 etc.)
 	  or both.
 
+	  To compile this driver as a module, say M here: the module will be
+	  called firewire-core.  It functionally replaces ieee1394, raw1394,
+	  and video1394.
+
+          NOTE:
+
+	  You should only build ONE of the stacks, unless you REALLY know what
+	  you are doing.  If you install both, you should configure them only as
+	  modules rather than link them statically, and you should blacklist one
+	  of the concurrent low-level drivers in /etc/modprobe.conf.  Add either
+
+	      blacklist firewire-ohci
+	  or
+	      blacklist ohci1394
+
+	  there depending on which driver you DON'T want to have auto-loaded.
+	  You can optionally do the same with the other IEEE 1394/ FireWire
+	  drivers.
+
+	  If you have an old modprobe which doesn't implement the blacklist
+	  directive, use either
+
+	       install firewire-ohci /bin/true
+	  or
+	       install ohci1394 /bin/true
+
+	  and so on, depending on which modules you DON't want to have
+	  auto-loaded.
+
 config FIREWIRE_OHCI
 	tristate "Support for OHCI FireWire host controllers"
 	depends on PCI && FIREWIRE
@@ -34,11 +51,13 @@ config FIREWIRE_OHCI
 	  is the only chipset in use, so say Y here.
 
 	  To compile this driver as a module, say M here:  The module will be
-	  called firewire-ohci.
+	  called firewire-ohci.  It replaces ohci1394 of the classic IEEE 1394
+	  stack.
 
-	  If you also build ohci1394 of the classic IEEE 1394 driver stack,
+          NOTE:
-	  blacklist either ohci1394 or firewire-ohci to let hotplug load the
+
-	  desired driver.
+	  If you also build ohci1394 of the classic stack, blacklist either
+	  ohci1394 or firewire-ohci to let hotplug load only the desired driver.
 
 config FIREWIRE_SBP2
 	tristate "Support for storage devices (SBP-2 protocol driver)"
@@ -50,12 +69,14 @@ config FIREWIRE_SBP2
 	  like scanners.
 
 	  To compile this driver as a module, say M here:  The module will be
-	  called firewire-sbp2.
+	  called firewire-sbp2.  It replaces sbp2 of the classic IEEE 1394
+	  stack.
 
 	  You should also enable support for disks, CD-ROMs, etc. in the SCSI
 	  configuration section.
 
-	  If you also build sbp2 of the classic IEEE 1394 driver stack,
+          NOTE:
-	  blacklist either sbp2 or firewire-sbp2 to let hotplug load the
+
-	  desired driver.
+	  If you also build sbp2 of the classic stack, blacklist either sbp2
+	  or firewire-sbp2 to let hotplug load only the desired driver.