gpio: Add DM GPIO driver for Marvell MVEBU

This patch adds a DM GPIO driver for the Marvell MVEBU SoCs. There are
other non-DM drivers that might be used on these platforms. But this
patch creates a new DM driver. Which will be used by all Armada XP/38x
boards. Other MVEBU SoC (Kirkwood / Orion) may follow once they
support DM as well.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Dirk Eibach <dirk.eibach@gdsys.cc>
Cc: Phil Sutter <phil@nwl.cc>
Cc: Kevin Smith <kevin.smith@elecsyscorp.com>
Cc: Luka Perkov <luka.perkov@sartura.hr>
Cc: Tom Rini <trini@konsulko.com>
Reviewed-by: Kevin Smith <kevin.smith@elecsyscorp.com>
Tested-by: Kevin Smith <kevin.smith@elecsyscorp.com>
Signed-off-by: Stefan Roese <sr@denx.de>

drivers/gpio/Kconfig

@@ -105,4 +105,11 @@ config PIC32_GPIO
 	help
 	  Say yes here to support Microchip PIC32 GPIOs.
 
+config MVEBU_GPIO
+	bool "Marvell MVEBU GPIO driver"
+	depends on DM_GPIO && ARCH_MVEBU
+	default y
+	help
+	  Say yes here to support Marvell MVEBU (Armada XP/38x) GPIOs.
+
 endmenu

drivers/gpio/Makefile

@@ -49,3 +49,4 @@ obj-$(CONFIG_ZYNQ_GPIO)		+= zynq_gpio.o
 obj-$(CONFIG_VYBRID_GPIO)	+= vybrid_gpio.o
 obj-$(CONFIG_HIKEY_GPIO)	+= hi6220_gpio.o
 obj-$(CONFIG_PIC32_GPIO)	+= pic32_gpio.o
+obj-$(CONFIG_MVEBU_GPIO)	+= mvebu_gpio.o

drivers/gpio/mvebu_gpio.c

@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 2016 Stefan Roese <sr@denx.de>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <asm/gpio.h>
+#include <asm/io.h>
+#include <errno.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define MVEBU_GPIOS_PER_BANK	32
+
+struct mvebu_gpio_regs {
+	u32 data_out;
+	u32 io_conf;
+	u32 blink_en;
+	u32 in_pol;
+	u32 data_in;
+};
+
+struct mvebu_gpio_priv {
+	struct mvebu_gpio_regs *regs;
+	char name[2];
+};
+
+static int mvebu_gpio_direction_input(struct udevice *dev, unsigned int gpio)
+{
+	struct mvebu_gpio_priv *priv = dev_get_priv(dev);
+	struct mvebu_gpio_regs *regs = priv->regs;
+
+	setbits_le32(&regs->io_conf, BIT(gpio));
+
+	return 0;
+}
+
+static int mvebu_gpio_direction_output(struct udevice *dev, unsigned gpio,
+				       int value)
+{
+	struct mvebu_gpio_priv *priv = dev_get_priv(dev);
+	struct mvebu_gpio_regs *regs = priv->regs;
+
+	clrbits_le32(&regs->io_conf, BIT(gpio));
+
+	return 0;
+}
+
+static int mvebu_gpio_get_function(struct udevice *dev, unsigned gpio)
+{
+	struct mvebu_gpio_priv *priv = dev_get_priv(dev);
+	struct mvebu_gpio_regs *regs = priv->regs;
+	u32 val;
+
+	val = readl(&regs->io_conf) & BIT(gpio);
+	if (val)
+		return GPIOF_INPUT;
+	else
+		return GPIOF_OUTPUT;
+}
+
+static int mvebu_gpio_set_value(struct udevice *dev, unsigned gpio,
+				int value)
+{
+	struct mvebu_gpio_priv *priv = dev_get_priv(dev);
+	struct mvebu_gpio_regs *regs = priv->regs;
+
+	if (value)
+		setbits_le32(&regs->data_out, BIT(gpio));
+	else
+		clrbits_le32(&regs->data_out, BIT(gpio));
+
+	return 0;
+}
+
+static int mvebu_gpio_get_value(struct udevice *dev, unsigned gpio)
+{
+	struct mvebu_gpio_priv *priv = dev_get_priv(dev);
+	struct mvebu_gpio_regs *regs = priv->regs;
+
+	return !!(readl(&regs->data_in) & BIT(gpio));
+}
+
+static int mvebu_gpio_probe(struct udevice *dev)
+{
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	struct mvebu_gpio_priv *priv = dev_get_priv(dev);
+
+	priv->regs = (struct mvebu_gpio_regs *)dev_get_addr(dev);
+	uc_priv->gpio_count = MVEBU_GPIOS_PER_BANK;
+	priv->name[0] = 'A' + dev->req_seq;
+	uc_priv->bank_name = priv->name;
+
+	return 0;
+}
+
+static const struct dm_gpio_ops mvebu_gpio_ops = {
+	.direction_input	= mvebu_gpio_direction_input,
+	.direction_output	= mvebu_gpio_direction_output,
+	.get_function		= mvebu_gpio_get_function,
+	.get_value		= mvebu_gpio_get_value,
+	.set_value		= mvebu_gpio_set_value,
+};
+
+static const struct udevice_id mvebu_gpio_ids[] = {
+	{ .compatible = "marvell,orion-gpio" },
+	{ }
+};
+
+U_BOOT_DRIVER(gpio_mvebu) = {
+	.name			= "gpio_mvebu",
+	.id			= UCLASS_GPIO,
+	.of_match		= mvebu_gpio_ids,
+	.ops			= &mvebu_gpio_ops,
+	.probe			= mvebu_gpio_probe,
+	.priv_auto_alloc_size	= sizeof(struct mvebu_gpio_priv),
+};