[U-Boot] [PATCH v1 4/8] lpc32xx: add GPIO support

[Albert ARIBAUD (3ADEV)]

Signed-off-by: Albert ARIBAUD (3ADEV) <albert.aribaud at 3adev.fr>
---

 arch/arm/include/asm/arch-lpc32xx/gpio.h |  43 ++++++
 drivers/gpio/Makefile                    |   1 +
 drivers/gpio/lpc32xx_gpio.c              | 223 +++++++++++++++++++++++++++++++
 3 files changed, 267 insertions(+)
 create mode 100644 arch/arm/include/asm/arch-lpc32xx/gpio.h
 create mode 100644 drivers/gpio/lpc32xx_gpio.c

diff --git a/arch/arm/include/asm/arch-lpc32xx/gpio.h b/arch/arm/include/asm/arch-lpc32xx/gpio.h
new file mode 100644
index 0000000..3bd94e3
--- /dev/null
+++ b/arch/arm/include/asm/arch-lpc32xx/gpio.h
@@ -0,0 +1,43 @@
+/*
+ * LPC32xx GPIO interface
+ *
+ * (C) Copyright 2014  DENX Software Engineering GmbH
+ * Written-by: Albert ARIBAUD <albert.aribaud at 3adev.fr>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+/**
+ * GPIO Register map for LPC32xx
+ */
+
+struct gpio_regs {
+	u32 p3_inp_state;
+	u32 p3_outp_set;
+	u32 p3_outp_clr;
+	u32 p3_outp_state;
+	/* Watch out! the following are shared between p2 and p3 */
+	u32 p2_p3_dir_set;
+	u32 p2_p3_dir_clr;
+	u32 p2_p3_dir_state;
+	/* Now back to 'one register for one port' */
+	u32 p2_inp_state;
+	u32 p2_outp_set;
+	u32 p2_outp_clr;
+	u32 reserved1[6];
+	u32 p0_inp_state;
+	u32 p0_outp_set;
+	u32 p0_outp_clr;
+	u32 p0_outp_state;
+	u32 p0_dir_set;
+	u32 p0_dir_clr;
+	u32 p0_dir_state;
+	u32 reserved2;
+	u32 p1_inp_state;
+	u32 p1_outp_set;
+	u32 p1_outp_clr;
+	u32 p1_outp_state;
+	u32 p1_dir_set;
+	u32 p1_dir_clr;
+	u32 p1_dir_state;
+};
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index aa11f15..559894a 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -37,3 +37,4 @@ obj-$(CONFIG_ADI_GPIO2)	+= adi_gpio2.o
 obj-$(CONFIG_TCA642X)		+= tca642x.o
 oby-$(CONFIG_SX151X)		+= sx151x.o
 obj-$(CONFIG_SUNXI_GPIO)	+= sunxi_gpio.o
+obj-$(CONFIG_LPC32XX_GPIO)	+= lpc32xx_gpio.o
diff --git a/drivers/gpio/lpc32xx_gpio.c b/drivers/gpio/lpc32xx_gpio.c
new file mode 100644
index 0000000..0c08b00
--- /dev/null
+++ b/drivers/gpio/lpc32xx_gpio.c
@@ -0,0 +1,223 @@
+/*
+ * LPC32xxGPIO driver
+ *
+ * (C) Copyright 2014  DENX Software Engineering GmbH
+ * Written-by: Albert ARIBAUD <albert.aribaud at 3adev.fr>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/errno.h>
+#include <asm/arch-lpc32xx/cpu.h>
+#include <asm/arch-lpc32xx/gpio.h>
+
+/**
+ * LPC32xx GPIOs work in banks but are non-homogeneous:
+ * - each bank holds a different number of GPIOs
+ * - some GPIOs are input/ouput, some input only, some output only;
+ * - some GPIOs have different meanings as an input and as an output;
+ * - some GPIOs are controlled on a given port and bit index, but
+ *   read on another one.
+*
+ * In order to keep this code simple, GPIOS are considered here as
+ * homogeneous and linear, from 0 to 127.
+ *
+ *	** WARNING **
+ *
+ * Client code is responsible for properly using valid GPIO numbers,
+ * including cases where reading back a GPIO is done on a different
+ * register and bit than writing it.
+ */
+
+static struct gpio_regs *regs = (struct gpio_regs *)GPIO_BASE;
+
+/**
+ * We have 4 GPIO ports of 32 bits each
+ */
+
+#define MAX_GPIO 128
+
+#define GPIO_TO_PORT(gpio) ((gpio / 32) & 3)
+#define GPIO_TO_RANK(gpio) (gpio % 32)
+#define GPIO_TO_MASK(gpio) (1 << (gpio % 32))
+
+/**
+ * GPIO requesting and freeing are not implemented
+ */
+
+int gpio_request(unsigned gpio, const char *label)
+{
+	debug("%s: GPIO %d requested as \"%s\"\n", __func__, gpio, label);
+	return 0;
+}
+
+int gpio_free(unsigned gpio)
+{
+	debug("%s: GPIO %d freed\n", __func__, gpio);
+	return 0;
+}
+
+/**
+ * Configure a GPIO as input
+ */
+
+int gpio_direction_input(unsigned gpio)
+{
+	int port, mask;
+
+	port = GPIO_TO_PORT(gpio);
+	mask = GPIO_TO_MASK(gpio);
+
+	switch (port) {
+	case 0:
+		writel(mask, &regs->p0_dir_clr);
+		break;
+	case 1:
+		writel(mask, &regs->p1_dir_clr);
+		break;
+	case 2:
+		/* ports 2 and 3 share a common direction */
+	case 3:
+		writel(mask, &regs->p2_p3_dir_clr);
+		break;
+	default:
+		return -1;
+	}
+	return 0;
+}
+
+/**
+ * Configure a GPIO as output
+ */
+
+int gpio_direction_output(unsigned gpio, int value)
+{
+	int port, mask;
+
+	port = GPIO_TO_PORT(gpio);
+	mask = GPIO_TO_MASK(gpio);
+
+	switch (port) {
+	case 0:
+		writel(mask, &regs->p0_dir_set);
+		break;
+	case 1:
+		writel(mask, &regs->p1_dir_set);
+		break;
+	case 2:
+		/* ports 2 and 3 share a common direction */
+	case 3:
+		writel(mask, &regs->p2_p3_dir_set);
+		break;
+	default:
+		return -1;
+	}
+	return 0;
+}
+
+/**
+ * Get the value of a GPIO
+ */
+
+int gpio_get_value(unsigned gpio)
+{
+	int port, rank, mask, value;
+
+	port = GPIO_TO_PORT(gpio);
+
+	switch (port) {
+	case 0:
+		value = readl(&regs->p0_inp_state);
+		break;
+	case 1:
+		value = readl(&regs->p1_inp_state);
+		break;
+	case 2:
+		value = readl(&regs->p2_inp_state);
+		break;
+	case 3:
+		value = readl(&regs->p3_inp_state);
+		break;
+	default:
+		return -1;
+	}
+
+	rank = GPIO_TO_RANK(gpio);
+	mask = GPIO_TO_MASK(gpio);
+
+	return (value & mask) >> rank;
+}
+
+/**
+ * Set a GPIO
+ */
+
+static int gpio_set(unsigned gpio)
+{
+	int port, mask;
+
+	port = GPIO_TO_PORT(gpio);
+	mask = GPIO_TO_MASK(gpio);
+
+	switch (port) {
+	case 0:
+		writel(mask, &regs->p0_outp_set);
+		break;
+	case 1:
+		writel(mask, &regs->p1_outp_set);
+		break;
+	case 2:
+		writel(mask, &regs->p2_outp_set);
+		break;
+	case 3:
+		writel(mask, &regs->p3_outp_set);
+		break;
+	default:
+		return -1;
+	}
+	return 0;
+}
+
+/**
+ * Clear a GPIO
+ */
+
+static int gpio_clr(unsigned gpio)
+{
+	int port, mask;
+
+	port = GPIO_TO_PORT(gpio);
+	mask = GPIO_TO_MASK(gpio);
+
+	switch (port) {
+	case 0:
+		writel(mask, &regs->p0_outp_clr);
+		break;
+	case 1:
+		writel(mask, &regs->p1_outp_clr);
+		break;
+	case 2:
+		writel(mask, &regs->p2_outp_clr);
+		break;
+	case 3:
+		writel(mask, &regs->p3_outp_clr);
+		break;
+	default:
+		return -1;
+	}
+	return 0;
+}
+
+/**
+ * Set the value of a GPIO
+ */
+
+int gpio_set_value(unsigned gpio, int value)
+{
+	if (value)
+		return gpio_set(gpio);
+	else
+		return gpio_clr(gpio);
+}
-- 
2.1.0