add HAVE_CLK to Kconfig, for driver dependencies

Flag platforms as HAVE_CLK (or not) in Kconfig, based on whether they
support <linux/clk.h> calls, so that otherwise portable drivers which need
those calls can list that dependency.

Something like this is a prerequisite for merging the musb_hdrc driver,
currently used on platforms including Davinci, OMAP2430, OMAP3xx ...  and
the discrete TUSB6010 chip, which doesn't have a natural platform
dependency.  (Used with OMAP 2420 in current Nokia N8x0 tablets.)

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/Kconfig

@@ -42,3 +42,10 @@ config HAVE_DMA_ATTRS
 
 config USE_GENERIC_SMP_HELPERS
 	def_bool n
+
+config HAVE_CLK
+	def_bool n
+	help
+	  The <linux/clk.h> calls support software clock gating and
+	  thus are a key power management tool on many systems.
+

arch/arm/Kconfig

@@ -198,19 +198,22 @@ choice
 config ARCH_AAEC2000
 	bool "Agilent AAEC-2000 based"
 	select ARM_AMBA
+	select HAVE_CLK
 	help
 	  This enables support for systems based on the Agilent AAEC-2000
 
 config ARCH_INTEGRATOR
 	bool "ARM Ltd. Integrator family"
 	select ARM_AMBA
+	select HAVE_CLK
 	select ICST525
 	help
 	  Support for ARM's Integrator platform.
 
 config ARCH_REALVIEW
 	bool "ARM Ltd. RealView family"
 	select ARM_AMBA
+	select HAVE_CLK
 	select ICST307
 	select GENERIC_TIME
 	select GENERIC_CLOCKEVENTS
@@ -221,6 +224,7 @@ config ARCH_VERSATILE
 	bool "ARM Ltd. Versatile family"
 	select ARM_AMBA
 	select ARM_VIC
+	select HAVE_CLK
 	select ICST307
 	select GENERIC_TIME
 	select GENERIC_CLOCKEVENTS
@@ -262,6 +266,8 @@ config ARCH_EP93XX
 	select ARM_AMBA
 	select ARM_VIC
 	select GENERIC_GPIO
+	select HAVE_CLK
+	select HAVE_CLK
 	select HAVE_GPIO_LIB
 	help
 	  This enables support for the Cirrus EP93xx series of CPUs.
@@ -381,6 +387,7 @@ config ARCH_NS9XXX
 	select GENERIC_GPIO
 	select GENERIC_TIME
 	select GENERIC_CLOCKEVENTS
+	select HAVE_CLK
 	help
 	  Say Y here if you intend to run this kernel on a NetSilicon NS9xxx
 	  System.
@@ -430,6 +437,7 @@ config ARCH_ORION5X
 
 config ARCH_PNX4008
 	bool "Philips Nexperia PNX4008 Mobile"
+	select HAVE_CLK
 	help
 	  This enables support for Philips PNX4008 mobile platform.
 
@@ -438,6 +446,7 @@ config ARCH_PXA
 	depends on MMU
 	select ARCH_MTD_XIP
 	select GENERIC_GPIO
+	select HAVE_CLK
 	select HAVE_GPIO_LIB
 	select GENERIC_TIME
 	select GENERIC_CLOCKEVENTS
@@ -468,6 +477,7 @@ config ARCH_SA1100
 	select GENERIC_GPIO
 	select GENERIC_TIME
 	select GENERIC_CLOCKEVENTS
+	select HAVE_CLK
 	select TICK_ONESHOT
 	select HAVE_GPIO_LIB
 	help
@@ -476,6 +486,7 @@ config ARCH_SA1100
 config ARCH_S3C2410
 	bool "Samsung S3C2410, S3C2412, S3C2413, S3C2440, S3C2442, S3C2443"
 	select GENERIC_GPIO
+	select HAVE_CLK
 	help
 	  Samsung S3C2410X CPU based systems, such as the Simtec Electronics
 	  BAST (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or
@@ -503,12 +514,14 @@ config ARCH_DAVINCI
 	select GENERIC_TIME
 	select GENERIC_CLOCKEVENTS
 	select GENERIC_GPIO
+	select HAVE_CLK
 	help
 	  Support for TI's DaVinci platform.
 
 config ARCH_OMAP
 	bool "TI OMAP"
 	select GENERIC_GPIO
+	select HAVE_CLK
 	select HAVE_GPIO_LIB
 	select GENERIC_TIME
 	select GENERIC_CLOCKEVENTS

arch/avr32/Kconfig

@@ -10,6 +10,7 @@ config AVR32
 	# With EMBEDDED=n, we get lots of stuff automatically selected
 	# that we usually don't need on AVR32.
 	select EMBEDDED
+	select HAVE_CLK
 	select HAVE_OPROFILE
 	select HAVE_KPROBES
 	help

arch/powerpc/Kconfig

@@ -843,6 +843,7 @@ source "crypto/Kconfig"
 config PPC_CLOCK
 	bool
 	default n
+	select HAVE_CLK
 
 config PPC_LIB_RHEAP
 	bool

arch/sh/Kconfig

@@ -8,6 +8,7 @@ mainmenu "Linux/SuperH Kernel Configuration"
 config SUPERH
 	def_bool y
 	select EMBEDDED
+	select HAVE_CLK
 	select HAVE_IDE
 	select HAVE_OPROFILE
 	help