OMAP3 Port kernel omap gpio interface.

Port version 2.6.27 of the linux kernel's omap gpio interface to u-boot.
The orignal source is in linux/arch/arm/plat-omap/gpio.c

See doc/README.omap3 for instructions on use.

Signed-off-by: Tom Rix <Tom.Rix@windriver.com>

cpu/arm_cortexa8/omap3/Makefile

@@ -29,6 +29,7 @@ SOBJS	:= lowlevel_init.o
 
 COBJS	+= board.o
 COBJS	+= clock.o
+COBJS	+= gpio.o
 COBJS	+= mem.o
 COBJS	+= syslib.o
 COBJS	+= sys_info.o

cpu/arm_cortexa8/omap3/gpio.c

+/*
+ * Copyright (c) 2009 Wind River Systems, Inc.
+ * Tom Rix <Tom.Rix@windriver.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ * This work is derived from the linux 2.6.27 kernel source
+ * To fetch, use the kernel repository
+ * git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
+ * Use the v2.6.27 tag.
+ *
+ * Below is the original's header including its copyright
+ *
+ *  linux/arch/arm/plat-omap/gpio.c
+ *
+ * Support functions for OMAP GPIO
+ *
+ * Copyright (C) 2003-2005 Nokia Corporation
+ * Written by Juha Yrjölä <juha.yrjola@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <common.h>
+#include <asm/arch/gpio.h>
+#include <asm/io.h>
+#include <asm/errno.h>
+
+static struct gpio_bank gpio_bank_34xx[6] = {
+	{ (void *)OMAP34XX_GPIO1_BASE, METHOD_GPIO_24XX },
+	{ (void *)OMAP34XX_GPIO2_BASE, METHOD_GPIO_24XX },
+	{ (void *)OMAP34XX_GPIO3_BASE, METHOD_GPIO_24XX },
+	{ (void *)OMAP34XX_GPIO4_BASE, METHOD_GPIO_24XX },
+	{ (void *)OMAP34XX_GPIO5_BASE, METHOD_GPIO_24XX },
+	{ (void *)OMAP34XX_GPIO6_BASE, METHOD_GPIO_24XX },
+};
+
+static struct gpio_bank *gpio_bank = &gpio_bank_34xx[0];
+
+static inline struct gpio_bank *get_gpio_bank(int gpio)
+{
+	return &gpio_bank[gpio >> 5];
+}
+
+static inline int get_gpio_index(int gpio)
+{
+	return gpio & 0x1f;
+}
+
+static inline int gpio_valid(int gpio)
+{
+	if (gpio < 0)
+		return -1;
+	if (gpio < 192)
+		return 0;
+	return -1;
+}
+
+static int check_gpio(int gpio)
+{
+	if (gpio_valid(gpio) < 0) {
+		printf("ERROR : check_gpio: invalid GPIO %d\n", gpio);
+		return -1;
+	}
+	return 0;
+}
+
+static void _set_gpio_direction(struct gpio_bank *bank, int gpio, int is_input)
+{
+	void *reg = bank->base;
+	u32 l;
+
+	switch (bank->method) {
+	case METHOD_GPIO_24XX:
+		reg += OMAP24XX_GPIO_OE;
+		break;
+	default:
+		return;
+	}
+	l = __raw_readl(reg);
+	if (is_input)
+		l |= 1 << gpio;
+	else
+		l &= ~(1 << gpio);
+	__raw_writel(l, reg);
+}
+
+void omap_set_gpio_direction(int gpio, int is_input)
+{
+	struct gpio_bank *bank;
+
+	if (check_gpio(gpio) < 0)
+		return;
+	bank = get_gpio_bank(gpio);
+	_set_gpio_direction(bank, get_gpio_index(gpio), is_input);
+}
+
+static void _set_gpio_dataout(struct gpio_bank *bank, int gpio, int enable)
+{
+	void *reg = bank->base;
+	u32 l = 0;
+
+	switch (bank->method) {
+	case METHOD_GPIO_24XX:
+		if (enable)
+			reg += OMAP24XX_GPIO_SETDATAOUT;
+		else
+			reg += OMAP24XX_GPIO_CLEARDATAOUT;
+		l = 1 << gpio;
+		break;
+	default:
+		printf("omap3-gpio unknown bank method %s %d\n",
+		       __FILE__, __LINE__);
+		return;
+	}
+	__raw_writel(l, reg);
+}
+
+void omap_set_gpio_dataout(int gpio, int enable)
+{
+	struct gpio_bank *bank;
+
+	if (check_gpio(gpio) < 0)
+		return;
+	bank = get_gpio_bank(gpio);
+	_set_gpio_dataout(bank, get_gpio_index(gpio), enable);
+}
+
+int omap_get_gpio_datain(int gpio)
+{
+	struct gpio_bank *bank;
+	void *reg;
+
+	if (check_gpio(gpio) < 0)
+		return -EINVAL;
+	bank = get_gpio_bank(gpio);
+	reg = bank->base;
+	switch (bank->method) {
+	case METHOD_GPIO_24XX:
+		reg += OMAP24XX_GPIO_DATAIN;
+		break;
+	default:
+		return -EINVAL;
+	}
+	return (__raw_readl(reg)
+			& (1 << get_gpio_index(gpio))) != 0;
+}
+
+static void _reset_gpio(struct gpio_bank *bank, int gpio)
+{
+	_set_gpio_direction(bank, get_gpio_index(gpio), 1);
+}
+
+int omap_request_gpio(int gpio)
+{
+	if (check_gpio(gpio) < 0)
+		return -EINVAL;
+
+	return 0;
+}
+
+void omap_free_gpio(int gpio)
+{
+	struct gpio_bank *bank;
+
+	if (check_gpio(gpio) < 0)
+		return;
+	bank = get_gpio_bank(gpio);
+
+	_reset_gpio(bank, gpio);
+}

doc/README.omap3

@@ -84,6 +84,38 @@ For all other commands see
 
 help
 
+Interfaces
+==========
+
+gpio
+
+To set a bit :
+
+	if (!omap_request_gpio(N)) {
+		omap_set_gpio_direction(N, 0);
+		omap_set_gpio_dataout(N, 1);
+	}
+
+To clear a bit :
+
+	if (!omap_request_gpio(N)) {
+		omap_set_gpio_direction(N, 0);
+		omap_set_gpio_dataout(N, 0);
+	}
+
+To read a bit :
+
+	if (!omap_request_gpio(N)) {
+		omap_set_gpio_direction(NULL, 1);
+		val = omap_get_gpio_datain(N);
+		omap_free_gpio(N);
+	}
+	if (val)
+		printf("GPIO N is set\n");
+	else
+		printf("GPIO N is clear\n");
+
+
 Acknowledgements
 ================
 

include/asm-arm/arch-omap3/gpio.h

+/*
+ * Copyright (c) 2009 Wind River Systems, Inc.
+ * Tom Rix <Tom.Rix@windriver.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ * This work is derived from the linux 2.6.27 kernel source
+ * To fetch, use the kernel repository
+ * git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
+ * Use the v2.6.27 tag.
+ *
+ * Below is the original's header including its copyright
+ *
+ *  linux/arch/arm/plat-omap/gpio.c
+ *
+ * Support functions for OMAP GPIO
+ *
+ * Copyright (C) 2003-2005 Nokia Corporation
+ * Written by Juha Yrjölä <juha.yrjola@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef _GPIO_H
+#define _GPIO_H
+
+#define OMAP24XX_GPIO_REVISION		0x0000
+#define OMAP24XX_GPIO_SYSCONFIG		0x0010
+#define OMAP24XX_GPIO_SYSSTATUS		0x0014
+#define OMAP24XX_GPIO_IRQSTATUS1	0x0018
+#define OMAP24XX_GPIO_IRQSTATUS2	0x0028
+#define OMAP24XX_GPIO_IRQENABLE2	0x002c
+#define OMAP24XX_GPIO_IRQENABLE1	0x001c
+#define OMAP24XX_GPIO_WAKE_EN		0x0020
+#define OMAP24XX_GPIO_CTRL		0x0030
+#define OMAP24XX_GPIO_OE		0x0034
+#define OMAP24XX_GPIO_DATAIN		0x0038
+#define OMAP24XX_GPIO_DATAOUT		0x003c
+#define OMAP24XX_GPIO_LEVELDETECT0	0x0040
+#define OMAP24XX_GPIO_LEVELDETECT1	0x0044
+#define OMAP24XX_GPIO_RISINGDETECT	0x0048
+#define OMAP24XX_GPIO_FALLINGDETECT	0x004c
+#define OMAP24XX_GPIO_DEBOUNCE_EN	0x0050
+#define OMAP24XX_GPIO_DEBOUNCE_VAL	0x0054
+#define OMAP24XX_GPIO_CLEARIRQENABLE1	0x0060
+#define OMAP24XX_GPIO_SETIRQENABLE1	0x0064
+#define OMAP24XX_GPIO_CLEARWKUENA	0x0080
+#define OMAP24XX_GPIO_SETWKUENA		0x0084
+#define OMAP24XX_GPIO_CLEARDATAOUT	0x0090
+#define OMAP24XX_GPIO_SETDATAOUT	0x0094
+
+struct gpio_bank {
+	void *base;
+	int method;
+};
+
+#define METHOD_GPIO_24XX	4
+
+/* This is the interface */
+
+/* Request a gpio before using it */
+int omap_request_gpio(int gpio);
+/* Reset and free a gpio after using it */
+void omap_free_gpio(int gpio);
+/* Sets the gpio as input or output */
+void omap_set_gpio_direction(int gpio, int is_input);
+/* Set or clear a gpio output */
+void omap_set_gpio_dataout(int gpio, int enable);
+/* Get the value of a gpio input */
+int omap_get_gpio_datain(int gpio);
+
+#endif /* _GPIO_H_ */