gpio: Add Rapid GPIO2P driver for i.MX7ULP

Add the imx_rgpio2p driver for Rapid GPIO2P controllers on i.MX7ULP.
Have added all ports on RGPIO2P_0 and RGPIO2P_1.

The configurations CONFIG_IMX_RGPIO2P and CONFIG_DM_GPIO must be set
to y to enable the drivers.

To use the GPIO function, the IBE and OBE needs to set in IOMUXC.
We did not set the bits in driver, but leave them to IOMUXC settings
of the GPIO pins. User should use IMX_GPIO_NR to generate the GPIO number
for gpio APIs access.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Ye Li <ye.li@nxp.com>
Reviewed-by : Stefano Babic <sbabic@denx.de>

arch/arm/include/asm/arch-mx7ulp/gpio.h

@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __ASM_ARCH_MX7ULP_GPIO_H
+#define __ASM_ARCH_MX7ULP_GPIO_H
+
+struct gpio_regs {
+	u32 gpio_pdor;
+	u32 gpio_psor;
+	u32 gpio_pcor;
+	u32 gpio_ptor;
+	u32 gpio_pdir;
+	u32 gpio_pddr;
+	u32 gpio_gacr;
+};
+
+#define IMX_GPIO_NR(port, index)		((((port)-1)*32)+((index)&31))
+
+#endif /* __ASM_ARCH_MX7ULP_GPIO_H */

drivers/gpio/Kconfig

@@ -48,6 +48,13 @@ config INTEL_BROADWELL_GPIO
 	  driver from the common Intel ICH6 driver. It supports a total of
 	  95 GPIOs which can be configured from the device tree.
 
+config IMX_RGPIO2P
+	bool "i.MX7ULP RGPIO2P driver"
+	depends on DM
+	default n
+	help
+	  This driver supports i.MX7ULP Rapid GPIO2P controller.
+
 config LPC32XX_GPIO
 	bool "LPC32XX GPIO driver"
 	depends on DM

drivers/gpio/Makefile

@@ -53,6 +53,7 @@ obj-$(CONFIG_GPIO_UNIPHIER)	+= gpio-uniphier.o
 obj-$(CONFIG_ZYNQ_GPIO)		+= zynq_gpio.o
 obj-$(CONFIG_VYBRID_GPIO)	+= vybrid_gpio.o
 obj-$(CONFIG_HIKEY_GPIO)	+= hi6220_gpio.o
+obj-$(CONFIG_IMX_RGPIO2P)	+= imx_rgpio2p.o
 obj-$(CONFIG_PIC32_GPIO)	+= pic32_gpio.o
 obj-$(CONFIG_MVEBU_GPIO)	+= mvebu_gpio.o
 obj-$(CONFIG_MSM_GPIO)		+= msm_gpio.o

drivers/gpio/imx_rgpio2p.c

@@ -0,0 +1,224 @@
+/*
+ * Copyright 2016 Freescale Semiconductor, Inc.
+ *
+ * RGPIO2P driver for the Freescale i.MX7ULP.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <asm/gpio.h>
+#include <asm/io.h>
+#include <malloc.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+enum imx_rgpio2p_direction {
+	IMX_RGPIO2P_DIRECTION_IN,
+	IMX_RGPIO2P_DIRECTION_OUT,
+};
+
+#define GPIO_PER_BANK			32
+
+struct imx_rgpio2p_data {
+	struct gpio_regs *regs;
+};
+
+struct imx_rgpio2p_plat {
+	int bank_index;
+	struct gpio_regs *regs;
+};
+
+static int imx_rgpio2p_is_output(struct gpio_regs *regs, int offset)
+{
+	u32 val;
+
+	val = readl(&regs->gpio_pddr);
+
+	return val & (1 << offset) ? 1 : 0;
+}
+
+static void imx_rgpio2p_bank_direction(struct gpio_regs *regs, int offset,
+				    enum imx_rgpio2p_direction direction)
+{
+	u32 l;
+
+	l = readl(&regs->gpio_pddr);
+
+	switch (direction) {
+	case IMX_RGPIO2P_DIRECTION_OUT:
+		l |= 1 << offset;
+		break;
+	case IMX_RGPIO2P_DIRECTION_IN:
+		l &= ~(1 << offset);
+	}
+	writel(l, &regs->gpio_pddr);
+}
+
+static void imx_rgpio2p_bank_set_value(struct gpio_regs *regs, int offset,
+				    int value)
+{
+	if (value)
+		writel((1 << offset), &regs->gpio_psor);
+	else
+		writel((1 << offset), &regs->gpio_pcor);
+}
+
+static int imx_rgpio2p_bank_get_value(struct gpio_regs *regs, int offset)
+{
+	return (readl(&regs->gpio_pdir) >> offset) & 0x01;
+}
+
+static int  imx_rgpio2p_direction_input(struct udevice *dev, unsigned offset)
+{
+	struct imx_rgpio2p_data *bank = dev_get_priv(dev);
+
+	/* Configure GPIO direction as input. */
+	imx_rgpio2p_bank_direction(bank->regs, offset, IMX_RGPIO2P_DIRECTION_IN);
+
+	return 0;
+}
+
+static int imx_rgpio2p_direction_output(struct udevice *dev, unsigned offset,
+				       int value)
+{
+	struct imx_rgpio2p_data *bank = dev_get_priv(dev);
+
+	/* Configure GPIO output value. */
+	imx_rgpio2p_bank_set_value(bank->regs, offset, value);
+
+	/* Configure GPIO direction as output. */
+	imx_rgpio2p_bank_direction(bank->regs, offset, IMX_RGPIO2P_DIRECTION_OUT);
+
+	return 0;
+}
+
+static int imx_rgpio2p_get_value(struct udevice *dev, unsigned offset)
+{
+	struct imx_rgpio2p_data *bank = dev_get_priv(dev);
+
+	return imx_rgpio2p_bank_get_value(bank->regs, offset);
+}
+
+static int imx_rgpio2p_set_value(struct udevice *dev, unsigned offset,
+				 int value)
+{
+	struct imx_rgpio2p_data *bank = dev_get_priv(dev);
+
+	imx_rgpio2p_bank_set_value(bank->regs, offset, value);
+
+	return 0;
+}
+
+static int imx_rgpio2p_get_function(struct udevice *dev, unsigned offset)
+{
+	struct imx_rgpio2p_data *bank = dev_get_priv(dev);
+
+	/* GPIOF_FUNC is not implemented yet */
+	if (imx_rgpio2p_is_output(bank->regs, offset))
+		return GPIOF_OUTPUT;
+	else
+		return GPIOF_INPUT;
+}
+
+static const struct dm_gpio_ops imx_rgpio2p_ops = {
+	.direction_input	= imx_rgpio2p_direction_input,
+	.direction_output	= imx_rgpio2p_direction_output,
+	.get_value		= imx_rgpio2p_get_value,
+	.set_value		= imx_rgpio2p_set_value,
+	.get_function		= imx_rgpio2p_get_function,
+};
+
+static int imx_rgpio2p_probe(struct udevice *dev)
+{
+	struct imx_rgpio2p_data *bank = dev_get_priv(dev);
+	struct imx_rgpio2p_plat *plat = dev_get_platdata(dev);
+	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+	int banknum;
+	char name[18], *str;
+
+	banknum = plat->bank_index;
+	sprintf(name, "GPIO%d_", banknum + 1);
+	str = strdup(name);
+	if (!str)
+		return -ENOMEM;
+	uc_priv->bank_name = str;
+	uc_priv->gpio_count = GPIO_PER_BANK;
+	bank->regs = plat->regs;
+
+	return 0;
+}
+
+static int imx_rgpio2p_bind(struct udevice *dev)
+{
+	struct imx_rgpio2p_plat *plat = dev->platdata;
+	fdt_addr_t addr;
+
+	/*
+	 * If platdata already exsits, directly return.
+	 * Actually only when DT is not supported, platdata
+	 * is statically initialized in U_BOOT_DEVICES.Here
+	 * will return.
+	 */
+	if (plat)
+		return 0;
+
+	addr = dev_get_addr_index(dev, 1);
+	if (addr == FDT_ADDR_T_NONE)
+		return -ENODEV;
+
+	/*
+	 * TODO:
+	 * When every board is converted to driver model and DT is supported,
+	 * this can be done by auto-alloc feature, but not using calloc
+	 * to alloc memory for platdata.
+	 */
+	plat = calloc(1, sizeof(*plat));
+	if (!plat)
+		return -ENOMEM;
+
+	plat->regs = (struct gpio_regs *)addr;
+	plat->bank_index = dev->req_seq;
+	dev->platdata = plat;
+
+	return 0;
+}
+
+
+static const struct udevice_id imx_rgpio2p_ids[] = {
+	{ .compatible = "fsl,imx7ulp-gpio" },
+	{ }
+};
+
+U_BOOT_DRIVER(imx_rgpio2p) = {
+	.name	= "imx_rgpio2p",
+	.id	= UCLASS_GPIO,
+	.ops	= &imx_rgpio2p_ops,
+	.probe	= imx_rgpio2p_probe,
+	.priv_auto_alloc_size = sizeof(struct imx_rgpio2p_plat),
+	.of_match = imx_rgpio2p_ids,
+	.bind	= imx_rgpio2p_bind,
+};
+
+#if !CONFIG_IS_ENABLED(OF_CONTROL)
+static const struct imx_rgpio2p_plat imx_plat[] = {
+	{ 0, (struct gpio_regs *)RGPIO2P_GPIO1_BASE_ADDR },
+	{ 1, (struct gpio_regs *)RGPIO2P_GPIO2_BASE_ADDR },
+	{ 2, (struct gpio_regs *)RGPIO2P_GPIO3_BASE_ADDR },
+	{ 3, (struct gpio_regs *)RGPIO2P_GPIO4_BASE_ADDR },
+	{ 4, (struct gpio_regs *)RGPIO2P_GPIO5_BASE_ADDR },
+	{ 5, (struct gpio_regs *)RGPIO2P_GPIO6_BASE_ADDR },
+};
+
+U_BOOT_DEVICES(imx_rgpio2ps) = {
+	{ "imx_rgpio2p", &imx_plat[0] },
+	{ "imx_rgpio2p", &imx_plat[1] },
+	{ "imx_rgpio2p", &imx_plat[2] },
+	{ "imx_rgpio2p", &imx_plat[3] },
+	{ "imx_rgpio2p", &imx_plat[4] },
+	{ "imx_rgpio2p", &imx_plat[5] },
+};
+#endif