mfd: Add driver for STA2X11 MFD block

This also introduces <asm/sta2x11.h> to export a function that is in
the base sta2x11 support patches. The header will increase with other
prototypes and constants over time.
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

arch/x86/include/asm/sta2x11.h

+/*
+ * Header file for STMicroelectronics ConneXt (STA2X11) IOHub
+ */
+#ifndef __ASM_STA2X11_H
+#define __ASM_STA2X11_H
+
+#include <linux/pci.h>
+
+/* This needs to be called from the MFD to configure its sub-devices */
+struct sta2x11_instance *sta2x11_get_instance(struct pci_dev *pdev);
+
+#endif /* __ASM_STA2X11_H */

drivers/mfd/Kconfig

@@ -906,6 +906,11 @@ config MFD_RC5T583
 	  Additional drivers must be enabled in order to use the
 	  different functionality of the device.
 
+config MFD_STA2X11
+	bool "STA2X11 multi function device support"
+	depends on STA2X11
+	select MFD_CORE
+
 config MFD_ANATOP
 	bool "Support for Freescale i.MX on-chip ANATOP controller"
 	depends on SOC_IMX6Q

drivers/mfd/Makefile

@@ -15,6 +15,7 @@ obj-$(CONFIG_MFD_DAVINCI_VOICECODEC)	+= davinci_voicecodec.o
 obj-$(CONFIG_MFD_DM355EVM_MSP)	+= dm355evm_msp.o
 obj-$(CONFIG_MFD_TI_SSP)	+= ti-ssp.o
 
+obj-$(CONFIG_MFD_STA2X11)	+= sta2x11-mfd.o
 obj-$(CONFIG_MFD_STMPE)		+= stmpe.o
 obj-$(CONFIG_STMPE_I2C)		+= stmpe-i2c.o
 obj-$(CONFIG_STMPE_SPI)		+= stmpe-spi.o