gpio: renesas: Add RZ/A1 R7S72100 GPIO driver

Add GPIO driver for RZ/A1 SoC. The IP is very different from the
R-Car Gen2/Gen3 one already present in the tree, hence a custom
driver.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Chris Brandt <chris.brandt@renesas.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>

3 files changed, 141 insertions, 0 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 684ca9d868..e36a8abc42 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -169,6 +169,12 @@ config RCAR_GPIO
 	help
 	  This driver supports the GPIO banks on Renesas RCar SoCs.
 
+config RZA1_GPIO
+	bool "Renesas RZ/A1 GPIO driver"
+	depends on DM_GPIO && RZA1
+	help
+	  This driver supports the GPIO banks on Renesas RZ/A1 R7S72100 SoCs.
+
 config ROCKCHIP_GPIO
 	bool "Rockchip GPIO driver"
 	depends on DM_GPIO
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 3be325044f..7337153e0e 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -27,6 +27,7 @@ obj-$(CONFIG_PCA953X)		+= pca953x.o
 obj-$(CONFIG_PCA9698)		+= pca9698.o
 obj-$(CONFIG_ROCKCHIP_GPIO)	+= rk_gpio.o
 obj-$(CONFIG_RCAR_GPIO)		+= gpio-rcar.o
+obj-$(CONFIG_RZA1_GPIO)		+= gpio-rza1.o
 obj-$(CONFIG_S5P)		+= s5p_gpio.o
 obj-$(CONFIG_SANDBOX_GPIO)	+= sandbox.o
 obj-$(CONFIG_SPEAR_GPIO)	+= spear_gpio.o
diff --git a/drivers/gpio/gpio-rza1.c b/drivers/gpio/gpio-rza1.c
new file mode 100644
index 0000000000..ce2453e2ba
--- /dev/null
+++ b/drivers/gpio/gpio-rza1.c
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019 Marek Vasut <marek.vasut@gmail.com>
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <dm.h>
+#include <errno.h>
+#include <asm/gpio.h>
+#include <asm/io.h>
+
+#define P(bank)			(0x0000 + (bank) * 4)
+#define PSR(bank)		(0x0100 + (bank) * 4)
+#define PPR(bank)		(0x0200 + (bank) * 4)
+#define PM(bank)		(0x0300 + (bank) * 4)
+#define PMC(bank)		(0x0400 + (bank) * 4)
+#define PFC(bank)		(0x0500 + (bank) * 4)
+#define PFCE(bank)		(0x0600 + (bank) * 4)
+#define PNOT(bank)		(0x0700 + (bank) * 4)
+#define PMSR(bank)		(0x0800 + (bank) * 4)
+#define PMCSR(bank)		(0x0900 + (bank) * 4)
+#define PFCAE(bank)		(0x0A00 + (bank) * 4)
+#define PIBC(bank)		(0x4000 + (bank) * 4)
+#define PBDC(bank)		(0x4100 + (bank) * 4)
+#define PIPC(bank)		(0x4200 + (bank) * 4)
+
+#define RZA1_MAX_GPIO_PER_BANK	16
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct r7s72100_gpio_priv {
+	void __iomem		*regs;
+	int			bank;
+};
+
+static int r7s72100_gpio_get_value(struct udevice *dev, unsigned offset)
+{
+	struct r7s72100_gpio_priv *priv = dev_get_priv(dev);
+
+	return !!(readw(priv->regs + PPR(priv->bank)) & BIT(offset));
+}
+
+static int r7s72100_gpio_set_value(struct udevice *dev, unsigned line,
+			       int value)
+{
+	struct r7s72100_gpio_priv *priv = dev_get_priv(dev);
+
+	writel(BIT(line + 16) | (value ? BIT(line) : 0),
+	       priv->regs + PSR(priv->bank));
+
+	return 0;
+}
+
+static void r7s72100_gpio_set_direction(struct udevice *dev, unsigned line,
+					bool output)
+{
+	struct r7s72100_gpio_priv *priv = dev_get_priv(dev);
+
+	writel(BIT(line + 16), priv->regs + PMCSR(priv->bank));
+	writel(BIT(line + 16) | (output ? 0 : BIT(line)),
+	       priv->regs + PMSR(priv->bank));
+
+	clrsetbits_le16(priv->regs + PIBC(priv->bank), BIT(line),
+			output ? 0 : BIT(line));
+}
+
+static int r7s72100_gpio_direction_input(struct udevice *dev, unsigned offset)
+{
+	r7s72100_gpio_set_direction(dev, offset, false);
+	return 0;
+}
+
+static int r7s72100_gpio_direction_output(struct udevice *dev, unsigned offset,
+				      int value)
+{
+	/* write GPIO value to output before selecting output mode of pin */
+	r7s72100_gpio_set_value(dev, offset, value);
+	r7s72100_gpio_set_direction(dev, offset, true);
+
+	return 0;
+}
+
+static int r7s72100_gpio_get_function(struct udevice *dev, unsigned offset)
+{
+	struct r7s72100_gpio_priv *priv = dev_get_priv(dev);
+
+	if (readw(priv->regs + PM(priv->bank)) & BIT(offset))
+		return GPIOF_INPUT;
+	else
+		return GPIOF_OUTPUT;
+}
+
+static const struct dm_gpio_ops r7s72100_gpio_ops = {
+	.direction_input	= r7s72100_gpio_direction_input,
+	.direction_output	= r7s72100_gpio_direction_output,
+	.get_value		= r7s72100_gpio_get_value,
+	.set_value		= r7s72100_gpio_set_value,
+	.get_function		= r7s72100_gpio_get_function,
+};
+
+static int r7s72100_gpio_probe(struct udevice *dev)
+{
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	struct r7s72100_gpio_priv *priv = dev_get_priv(dev);
+	struct fdtdec_phandle_args args;
+	int node = dev_of_offset(dev);
+	int ret;
+
+	fdt_addr_t addr_base;
+
+	uc_priv->bank_name = dev->name;
+	dev = dev_get_parent(dev);
+	addr_base = devfdt_get_addr(dev);
+	if (addr_base == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	priv->regs = (void __iomem *)addr_base;
+
+	ret = fdtdec_parse_phandle_with_args(gd->fdt_blob, node, "gpio-ranges",
+					     NULL, 3, 0, &args);
+	priv->bank = ret == 0 ? (args.args[1] / RZA1_MAX_GPIO_PER_BANK) : -1;
+	uc_priv->gpio_count = ret == 0 ? args.args[2] : RZA1_MAX_GPIO_PER_BANK;
+
+	return 0;
+}
+
+U_BOOT_DRIVER(r7s72100_gpio) = {
+	.name	= "r7s72100-gpio",
+	.id	= UCLASS_GPIO,
+	.ops	= &r7s72100_gpio_ops,
+	.priv_auto_alloc_size = sizeof(struct r7s72100_gpio_priv),
+	.probe	= r7s72100_gpio_probe,
+};