[ARM] 4275/1: generic gpio layer for ixp4xx

This patch brings generic gpio layer support to ixp4xx. It creates
functions needed for gpio->irq and irq->gpio translation.

It expects and initial value to be passed to
gpio_direction_output() which has been introduced by
commit 28735a7253 in Linus git tree.

Generic gpio layer is going to be used by pxa2xx_udc driver.

Signed-off-by: Milan Svoboda <msvoboda@ra.rockwell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-ixp4xx/common.c

@@ -102,6 +102,29 @@ static signed char irq2gpio[32] = {
 	 7,  8,  9, 10, 11, 12, -1, -1,
 };
 
+int gpio_to_irq(int gpio)
+{
+	int irq;
+
+	for (irq = 0; irq < 32; irq++) {
+		if (irq2gpio[irq] == gpio)
+			return irq;
+	}
+	return -EINVAL;
+}
+EXPORT_SYMBOL(gpio_to_irq);
+
+int irq_to_gpio(int irq)
+{
+	int gpio = (irq < 32) ? irq2gpio[irq] : -EINVAL;
+
+	if (gpio == -1)
+		return -EINVAL;
+
+	return gpio;
+}
+EXPORT_SYMBOL(irq_to_gpio);
+
 static int ixp4xx_set_irq_type(unsigned int irq, unsigned int type)
 {
 	int line = irq2gpio[irq];

include/asm-arm/arch-ixp4xx/gpio.h

@@ -0,0 +1,73 @@
+/*
+ * linux/include/asm-arm/arch-ixp4xx/gpio.h
+ *
+ * IXP4XX GPIO wrappers for arch-neutral GPIO calls
+ *
+ * Written by Milan Svoboda <msvoboda@ra.rockwell.com>
+ * Based on PXA implementation by Philipp Zabel <philipp.zabel@gmail.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
+ *
+ */
+
+#ifndef __ASM_ARCH_IXP4XX_GPIO_H
+#define __ASM_ARCH_IXP4XX_GPIO_H
+
+#include <asm/hardware.h>
+
+static inline int gpio_request(unsigned gpio, const char *label)
+{
+	return 0;
+}
+
+static inline void gpio_free(unsigned gpio)
+{
+	return;
+}
+
+static inline int gpio_direction_input(unsigned gpio)
+{
+	gpio_line_config(gpio, IXP4XX_GPIO_IN);
+	return 0;
+}
+
+static inline int gpio_direction_output(unsigned gpio, int level)
+{
+	gpio_line_set(gpio, level);
+	gpio_line_config(gpio, IXP4XX_GPIO_OUT);
+	return 0;
+}
+
+static inline int gpio_get_value(unsigned gpio)
+{
+	int value;
+
+	gpio_line_get(gpio, &value);
+
+	return value;
+}
+
+static inline void gpio_set_value(unsigned gpio, int value)
+{
+	gpio_line_set(gpio, value);
+}
+
+#include <asm-generic/gpio.h>			/* cansleep wrappers */
+
+extern int gpio_to_irq(int gpio);
+extern int irq_to_gpio(int gpio);
+
+#endif
+