gpio: uniphier: add driver for UniPhier GPIO controller

This GPIO controller device is used on UniPhier SoCs.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>

drivers/gpio/gpio-uniphier.c

@@ -0,0 +1,147 @@
+/*
+ * Copyright (C) 2016 Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm/device.h>
+#include <mapmem.h>
+#include <linux/bitops.h>
+#include <linux/io.h>
+#include <asm/errno.h>
+#include <asm/gpio.h>
+
+#define UNIPHIER_GPIO_PORTS_PER_BANK	8
+
+#define UNIPHIER_GPIO_REG_DATA		0	/* data */
+#define UNIPHIER_GPIO_REG_DIR		4	/* direction (1:in, 0:out) */
+
+struct uniphier_gpio_priv {
+	void __iomem *base;
+	char bank_name[16];
+};
+
+static void uniphier_gpio_offset_write(struct udevice *dev, unsigned offset,
+				       unsigned reg, int value)
+{
+	struct uniphier_gpio_priv *priv = dev_get_priv(dev);
+	u32 tmp;
+
+	tmp = readl(priv->base + reg);
+	if (value)
+		tmp |= BIT(offset);
+	else
+		tmp &= ~BIT(offset);
+	writel(tmp, priv->base + reg);
+}
+
+static int uniphier_gpio_offset_read(struct udevice *dev, unsigned offset,
+				     unsigned reg)
+{
+	struct uniphier_gpio_priv *priv = dev_get_priv(dev);
+
+	return !!(readl(priv->base + reg) & BIT(offset));
+}
+
+static int uniphier_gpio_direction_input(struct udevice *dev, unsigned offset)
+{
+	uniphier_gpio_offset_write(dev, offset, UNIPHIER_GPIO_REG_DIR, 1);
+
+	return 0;
+}
+
+static int uniphier_gpio_direction_output(struct udevice *dev, unsigned offset,
+					  int value)
+{
+	uniphier_gpio_offset_write(dev, offset, UNIPHIER_GPIO_REG_DATA, value);
+	uniphier_gpio_offset_write(dev, offset, UNIPHIER_GPIO_REG_DIR, 0);
+
+	return 0;
+}
+
+static int uniphier_gpio_get_value(struct udevice *dev, unsigned offset)
+{
+	return uniphier_gpio_offset_read(dev, offset, UNIPHIER_GPIO_REG_DATA);
+}
+
+static int uniphier_gpio_set_value(struct udevice *dev, unsigned offset,
+				   int value)
+{
+	uniphier_gpio_offset_write(dev, offset, UNIPHIER_GPIO_REG_DATA, value);
+
+	return 0;
+}
+
+static int uniphier_gpio_get_function(struct udevice *dev, unsigned offset)
+{
+	return uniphier_gpio_offset_read(dev, offset, UNIPHIER_GPIO_REG_DIR) ?
+						GPIOF_INPUT : GPIOF_OUTPUT;
+}
+
+static const struct dm_gpio_ops uniphier_gpio_ops = {
+	.direction_input	= uniphier_gpio_direction_input,
+	.direction_output	= uniphier_gpio_direction_output,
+	.get_value		= uniphier_gpio_get_value,
+	.set_value		= uniphier_gpio_set_value,
+	.get_function		= uniphier_gpio_get_function,
+};
+
+static int uniphier_gpio_probe(struct udevice *dev)
+{
+	struct uniphier_gpio_priv *priv = dev_get_priv(dev);
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	DECLARE_GLOBAL_DATA_PTR;
+	fdt_addr_t addr;
+	fdt_size_t size;
+	unsigned int tmp;
+
+	addr = fdtdec_get_addr_size(gd->fdt_blob, dev->of_offset, "reg",
+				    &size);
+	if (addr == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	priv->base = map_sysmem(addr, size);
+	if (!priv->base)
+		return -ENOMEM;
+
+	uc_priv->gpio_count = UNIPHIER_GPIO_PORTS_PER_BANK;
+
+	tmp = (addr & 0xfff);
+
+	/* Unfortunately, there is a register hole at offset 0x90-0x9f. */
+	if (tmp > 0x90)
+		tmp -= 0x10;
+
+	snprintf(priv->bank_name, sizeof(priv->bank_name) - 1,
+		 "port%d-", (tmp - 8) / 8);
+
+	uc_priv->bank_name = priv->bank_name;
+
+	return 0;
+}
+
+static int uniphier_gpio_remove(struct udevice *dev)
+{
+	struct uniphier_gpio_priv *priv = dev_get_priv(dev);
+
+	unmap_sysmem(priv->base);
+
+	return 0;
+}
+
+/* .data = the number of GPIO banks */
+static const struct udevice_id uniphier_gpio_match[] = {
+	{ .compatible = "socionext,uniphier-gpio" },
+	{ /* sentinel */ }
+};
+
+U_BOOT_DRIVER(uniphier_gpio) = {
+	.name	= "uniphier_gpio",
+	.id	= UCLASS_GPIO,
+	.of_match = uniphier_gpio_match,
+	.probe	= uniphier_gpio_probe,
+	.remove	= uniphier_gpio_remove,
+	.priv_auto_alloc_size = sizeof(struct uniphier_gpio_priv),
+	.ops	= &uniphier_gpio_ops,
+};