phy: add a NO-OP phy driver

This driver is used to stub PHY operations in a driver (USB, SATA).
This is useful when the 'client' driver (USB, SATA, ...) uses the PHY
framework and there is no actual PHY harwdare to drive.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 7841554..98f2a1b 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -41,6 +41,24 @@
 	  This select a dummy sandbox PHY driver. It used only to implement
 	  the unit tests for the phy framework
 
+config NOP_PHY
+	bool "NOP PHY driver"
+	depends on PHY
+	help
+	  Support for a no-op PHY driver (stubbed PHY driver).
+
+	  This is useful when a driver uses the PHY framework but no real PHY
+	  hardware exists.
+
+config SPL_NOP_PHY
+	bool "NOP PHY driver in SPL"
+	depends on SPL_PHY
+	help
+	  Support for a no-op PHY driver (stubbed PHY driver) in the SPL.
+
+	  This is useful when a driver uses the PHY framework but no real PHY
+	  hardware exists.
+
 config PIPE3_PHY
 	bool "Support omap's PIPE3 PHY"
 	depends on PHY && ARCH_OMAP2PLUS