powerpc/cell: Fix dependency in cpufreq

cbe_cpufreq has a partial dependency on cbe_cpufreq_pmi, which cannot
be easily expressed in Kconfig. This fixes it by introducing an
extra Kconfig symbol CBE_CPUFREQ_PMI_ENABLE. To make the dependency
clearer, turn PPC_PMI into an automatic symbol.

Reported-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/platforms/Kconfig

@@ -92,15 +92,6 @@ config RTAS_FLASH
 	tristate "Firmware flash interface"
 	depends on PPC64 && RTAS_PROC
 
-config PPC_PMI
-	tristate "Support for PMI"
-	depends on PPC_IBM_CELL_BLADE
-	help
-	  PMI (Platform Management Interrupt) is a way to
-	  communicate with the BMC (Baseboard Management Controller).
-	  It is used in some IBM Cell blades.
-	default m
-
 config MMIO_NVRAM
 	bool
 	default n

arch/powerpc/platforms/cell/Kconfig

@@ -98,7 +98,7 @@ config PPC_IBM_CELL_RESETBUTTON
 
 config PPC_IBM_CELL_POWERBUTTON
 	tristate "IBM Cell Blade power button"
-	depends on PPC_IBM_CELL_BLADE && PPC_PMI && INPUT_EVDEV
+	depends on PPC_IBM_CELL_BLADE && INPUT_EVDEV
 	default y
 	help
 	  Support Powerbutton on IBM Cell blades.
@@ -118,9 +118,9 @@ config CBE_CPUFREQ
 	  For details, take a look at <file:Documentation/cpu-freq/>.
 	  If you don't have such processor, say N
 
-config CBE_CPUFREQ_PMI
-	tristate "CBE frequency scaling using PMI interface"
-	depends on CBE_CPUFREQ && PPC_PMI && EXPERIMENTAL
+config CBE_CPUFREQ_PMI_ENABLE
+	bool "CBE frequency scaling using PMI interface"
+	depends on CBE_CPUFREQ && EXPERIMENTAL
 	default n
 	help
 	  Select this, if you want to use the PMI interface
@@ -128,6 +128,20 @@ config CBE_CPUFREQ_PMI
 	  processor will not only be able to run at lower speed,
 	  but also at lower core voltage.
 
+config CBE_CPUFREQ_PMI
+	tristate
+	depends on CBE_CPUFREQ_PMI_ENABLE
+	default CBE_CPUFREQ
+
+config PPC_PMI
+	tristate
+	default y
+	depends on CBE_CPUFREQ_PMI || PPC_IBM_CELL_POWERBUTTON
+	help
+	  PMI (Platform Management Interrupt) is a way to
+	  communicate with the BMC (Baseboard Management Controller).
+	  It is used in some IBM Cell blades.
+
 config CBE_CPUFREQ_SPU_GOVERNOR
 	tristate "CBE frequency scaling based on SPU usage"
 	depends on SPU_FS && CPU_FREQ