dm: gpio: add BCM6345 gpio driver

This driver is based on linux/arch/mips/bcm63xx/gpio.c, simplified to allow
defining one or two independent banks for each Broadcom SoC.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

drivers/gpio/Kconfig

@@ -21,6 +21,12 @@ config ALTERA_PIO
 	  Select this to enable PIO for Altera devices. Please find
 	  details on the "Embedded Peripherals IP User Guide" of Altera.
 
+config BCM6345_GPIO
+	bool "BCM6345 GPIO driver"
+	depends on DM_GPIO && ARCH_BMIPS
+	help
+	  This driver supports the GPIO banks on BCM6345 SoCs.
+
 config DWAPB_GPIO
 	bool "DWAPB GPIO driver"
 	depends on DM && DM_GPIO

drivers/gpio/Makefile

@@ -16,6 +16,7 @@ obj-$(CONFIG_DM_74X164)		+= 74x164_gpio.o
 
 obj-$(CONFIG_AT91_GPIO)	+= at91_gpio.o
 obj-$(CONFIG_ATMEL_PIO4)	+= atmel_pio4.o
+obj-$(CONFIG_BCM6345_GPIO)	+= bcm6345_gpio.o
 obj-$(CONFIG_INTEL_ICH6_GPIO)	+= intel_ich6_gpio.o
 obj-$(CONFIG_INTEL_BROADWELL_GPIO)	+= intel_broadwell_gpio.o
 obj-$(CONFIG_KIRKWOOD_GPIO)	+= kw_gpio.o

drivers/gpio/bcm6345_gpio.c

@@ -0,0 +1,125 @@
+/*
+ * Copyright (C) 2017 Álvaro Fernández Rojas <noltari@gmail.com>
+ *
+ * Derived from linux/arch/mips/bcm63xx/gpio.c:
+ *	Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
+ *	Copyright (C) 2008-2011 Florian Fainelli <florian@openwrt.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <asm/gpio.h>
+#include <asm/io.h>
+#include <dm/device.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct bcm6345_gpio_priv {
+	void __iomem *reg_dirout;
+	void __iomem *reg_data;
+};
+
+static int bcm6345_gpio_get_value(struct udevice *dev, unsigned offset)
+{
+	struct bcm6345_gpio_priv *priv = dev_get_priv(dev);
+
+	return !!(readl_be(priv->reg_data) & BIT(offset));
+}
+
+static int bcm6345_gpio_set_value(struct udevice *dev, unsigned offset,
+				  int value)
+{
+	struct bcm6345_gpio_priv *priv = dev_get_priv(dev);
+
+	if (value)
+		setbits_be32(priv->reg_data, BIT(offset));
+	else
+		clrbits_be32(priv->reg_data, BIT(offset));
+
+	return 0;
+}
+
+static int bcm6345_gpio_set_direction(void __iomem *dirout, unsigned offset,
+				      bool input)
+{
+	if (input)
+		clrbits_be32(dirout, BIT(offset));
+	else
+		setbits_be32(dirout, BIT(offset));
+
+	return 0;
+}
+
+static int bcm6345_gpio_direction_input(struct udevice *dev, unsigned offset)
+{
+	struct bcm6345_gpio_priv *priv = dev_get_priv(dev);
+
+	return bcm6345_gpio_set_direction(priv->reg_dirout, offset, 1);
+}
+
+static int bcm6345_gpio_direction_output(struct udevice *dev, unsigned offset,
+					 int value)
+{
+	struct bcm6345_gpio_priv *priv = dev_get_priv(dev);
+
+	return bcm6345_gpio_set_direction(priv->reg_dirout, offset, 0);
+}
+
+static int bcm6345_gpio_get_function(struct udevice *dev, unsigned offset)
+{
+	struct bcm6345_gpio_priv *priv = dev_get_priv(dev);
+
+	if (readl_be(priv->reg_dirout) & BIT(offset))
+		return GPIOF_OUTPUT;
+	else
+		return GPIOF_INPUT;
+}
+
+static const struct dm_gpio_ops bcm6345_gpio_ops = {
+	.direction_input = bcm6345_gpio_direction_input,
+	.direction_output = bcm6345_gpio_direction_output,
+	.get_value = bcm6345_gpio_get_value,
+	.set_value = bcm6345_gpio_set_value,
+	.get_function = bcm6345_gpio_get_function,
+};
+
+static int bcm6345_gpio_probe(struct udevice *dev)
+{
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	struct bcm6345_gpio_priv *priv = dev_get_priv(dev);
+	fdt_addr_t data_addr, dirout_addr;
+	fdt_size_t data_size, dirout_size;
+
+	dirout_addr = dev_get_addr_size_index(dev, 0, &dirout_size);
+	if (dirout_addr == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	data_addr = dev_get_addr_size_index(dev, 1, &data_size);
+	if (data_addr == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	priv->reg_data = ioremap(data_addr, data_size);
+	priv->reg_dirout = ioremap(dirout_addr, dirout_size);
+
+	uc_priv->gpio_count = fdtdec_get_uint(gd->fdt_blob, dev_of_offset(dev),
+					      "ngpios", 32);
+	uc_priv->bank_name = dev->name;
+
+	return 0;
+}
+
+static const struct udevice_id bcm6345_gpio_ids[] = {
+	{ .compatible = "brcm,bcm6345-gpio" },
+	{ /* sentinel */ }
+};
+
+U_BOOT_DRIVER(bcm6345_gpio) = {
+	.name = "bcm6345-gpio",
+	.id = UCLASS_GPIO,
+	.of_match = bcm6345_gpio_ids,
+	.ops = &bcm6345_gpio_ops,
+	.priv_auto_alloc_size = sizeof(struct bcm6345_gpio_priv),
+	.probe = bcm6345_gpio_probe,
+};