Add APM X-Gene SoC gpio controller driver.

Signed-off-by: Feng Kan <redacted>
---
 drivers/gpio/Kconfig      |   9 ++
 drivers/gpio/Makefile     |   1 +
 drivers/gpio/gpio-xgene.c | 252 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 262 insertions(+)
 create mode 100644 drivers/gpio/gpio-xgene.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 4a1b511..833996a02 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig

@@ -334,6 +334,15 @@ config GPIO_TZ1090_PDC
        help
          Say yes here to support Toumaz Xenif TZ1090 PDC GPIOs.

+config GPIO_XGENE
+       bool "APM X-Gene GPIO controller support"
+       depends on ARM64 && OF_GPIO
+       help
+         This driver is to support the GPIO block within the APM X-Gene SoC
+         platform's generic flash controller. The GPIO pins are muxed with
+         the generic flash controller's address and data pins. Say yes
+         here to enable the GFC GPIO functionality.
+
 config GPIO_XILINX
        bool "Xilinx GPIO support"
        depends on PPC_OF || MICROBLAZE || ARCH_ZYNQ

diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index d10f6a9..1bf5f82 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile

@@ -98,6 +98,7 @@ obj-$(CONFIG_GPIO_VX855)      += gpio-vx855.o
 obj-$(CONFIG_GPIO_WM831X)      += gpio-wm831x.o
 obj-$(CONFIG_GPIO_WM8350)      += gpio-wm8350.o
 obj-$(CONFIG_GPIO_WM8994)      += gpio-wm8994.o
+obj-$(CONFIG_GPIO_XGENE)       += gpio-xgene.o
 obj-$(CONFIG_GPIO_XILINX)      += gpio-xilinx.o
 obj-$(CONFIG_GPIO_XTENSA)      += gpio-xtensa.o
 obj-$(CONFIG_GPIO_ZEVIO)       += gpio-zevio.o

diff --git a/drivers/gpio/gpio-xgene.c b/drivers/gpio/gpio-xgene.c
new file mode 100644
index 0000000..3a747cc
--- /dev/null
+++ b/drivers/gpio/gpio-xgene.c

@@ -0,0 +1,252 @@
+/*
+ * AppliedMicro X-Gene SoC GPIO Driver
+ *
+ * Copyright (c) 2014, Applied Micro Circuits Corporation
+ * Author: Feng Kan <fkan@apm.com>.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <linux/platform_device.h>
+#include <linux/of_gpio.h>
+#include <linux/of.h>
+#include <linux/gpio.h>