Gemini: gpiolib based GPIO support v2

v2:
- update copyrights
Signed-off-by: Paulius Zaleckas <paulius.zaleckas@teltonika.lt>

arch/arm/Kconfig

@@ -278,6 +278,8 @@ config ARCH_EP93XX
 config ARCH_GEMINI
 	bool "Cortina Systems Gemini"
 	select CPU_FA526
+	select GENERIC_GPIO
+	select ARCH_REQUIRE_GPIOLIB
 	help
 	  Support for the Cortina Systems Gemini family SoCs
 

arch/arm/mach-gemini/Makefile

@@ -4,4 +4,4 @@
 
 # Object file lists.
 
-obj-y			:= irq.o mm.o time.o devices.o
+obj-y			:= irq.o mm.o time.o devices.o gpio.o

arch/arm/mach-gemini/common.h

@@ -17,6 +17,7 @@ struct mtd_partition;
 extern void gemini_map_io(void);
 extern void gemini_init_irq(void);
 extern void gemini_timer_init(void);
+extern void gemini_gpio_init(void);
 
 /* Common platform devices registration functions */
 extern int platform_register_uart(void);

arch/arm/mach-gemini/gpio.c

+/*
+ * Gemini gpiochip and interrupt routines
+ *
+ * Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
+ *
+ * Based on plat-mxc/gpio.c:
+ *  MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
+ *  Copyright 2008 Juergen Beisert, kernel@pengutronix.de
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/gpio.h>
+
+#include <mach/hardware.h>
+#include <mach/irqs.h>
+
+#define GPIO_BASE(x)		IO_ADDRESS(GEMINI_GPIO_BASE(x))
+
+/* GPIO registers definition */
+#define GPIO_DATA_OUT		0x0
+#define GPIO_DATA_IN		0x4
+#define GPIO_DIR		0x8
+#define GPIO_DATA_SET		0x10
+#define GPIO_DATA_CLR		0x14
+#define GPIO_PULL_EN		0x18
+#define GPIO_PULL_TYPE		0x1C
+#define GPIO_INT_EN		0x20
+#define GPIO_INT_STAT		0x24
+#define GPIO_INT_MASK		0x2C
+#define GPIO_INT_CLR		0x30
+#define GPIO_INT_TYPE		0x34
+#define GPIO_INT_BOTH_EDGE	0x38
+#define GPIO_INT_LEVEL		0x3C
+#define GPIO_DEBOUNCE_EN	0x40
+#define GPIO_DEBOUNCE_PRESCALE	0x44
+
+#define GPIO_PORT_NUM		3
+
+static void _set_gpio_irqenable(unsigned int base, unsigned int index,
+				int enable)
+{
+	unsigned int reg;
+
+	reg = __raw_readl(base + GPIO_INT_EN);
+	reg = (reg & (~(1 << index))) | (!!enable << index);
+	__raw_writel(reg, base + GPIO_INT_EN);
+}
+
+static void gpio_ack_irq(unsigned int irq)
+{
+	unsigned int gpio = irq_to_gpio(irq);
+	unsigned int base = GPIO_BASE(gpio / 32);
+
+	__raw_writel(1 << (gpio % 32), base + GPIO_INT_CLR);
+}
+
+static void gpio_mask_irq(unsigned int irq)
+{
+	unsigned int gpio = irq_to_gpio(irq);
+	unsigned int base = GPIO_BASE(gpio / 32);
+
+	_set_gpio_irqenable(base, gpio % 32, 0);
+}
+
+static void gpio_unmask_irq(unsigned int irq)
+{
+	unsigned int gpio = irq_to_gpio(irq);
+	unsigned int base = GPIO_BASE(gpio / 32);
+
+	_set_gpio_irqenable(base, gpio % 32, 1);
+}
+
+static int gpio_set_irq_type(unsigned int irq, unsigned int type)
+{
+	unsigned int gpio = irq_to_gpio(irq);
+	unsigned int gpio_mask = 1 << (gpio % 32);
+	unsigned int base = GPIO_BASE(gpio / 32);
+	unsigned int reg_both, reg_level, reg_type;
+
+	reg_type = __raw_readl(base + GPIO_INT_TYPE);
+	reg_level = __raw_readl(base + GPIO_INT_BOTH_EDGE);
+	reg_both = __raw_readl(base + GPIO_INT_BOTH_EDGE);
+
+	switch (type) {
+	case IRQ_TYPE_EDGE_BOTH:
+		reg_type &= ~gpio_mask;
+		reg_both |= gpio_mask;
+		break;
+	case IRQ_TYPE_EDGE_RISING:
+		reg_type &= ~gpio_mask;
+		reg_both &= ~gpio_mask;
+		reg_level &= ~gpio_mask;
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		reg_type &= ~gpio_mask;
+		reg_both &= ~gpio_mask;
+		reg_level |= gpio_mask;
+		break;
+	case IRQ_TYPE_LEVEL_HIGH:
+		reg_type |= gpio_mask;
+		reg_level &= ~gpio_mask;
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+		reg_type |= gpio_mask;
+		reg_level |= gpio_mask;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	__raw_writel(reg_type, base + GPIO_INT_TYPE);
+	__raw_writel(reg_level, base + GPIO_INT_BOTH_EDGE);
+	__raw_writel(reg_both, base + GPIO_INT_BOTH_EDGE);
+
+	gpio_ack_irq(irq);
+
+	return 0;
+}
+
+static void gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+	unsigned int gpio_irq_no, irq_stat;
+	unsigned int port = (unsigned int)get_irq_data(irq);
+
+	irq_stat = __raw_readl(GPIO_BASE(port) + GPIO_INT_STAT);
+
+	gpio_irq_no = GPIO_IRQ_BASE + port * 32;
+	for (; irq_stat != 0; irq_stat >>= 1, gpio_irq_no++) {
+
+		if ((irq_stat & 1) == 0)
+			continue;
+
+		BUG_ON(!(irq_desc[gpio_irq_no].handle_irq));
+		irq_desc[gpio_irq_no].handle_irq(gpio_irq_no,
+				&irq_desc[gpio_irq_no]);
+	}
+}
+
+static struct irq_chip gpio_irq_chip = {
+	.name = "GPIO",
+	.ack = gpio_ack_irq,
+	.mask = gpio_mask_irq,
+	.unmask = gpio_unmask_irq,
+	.set_type = gpio_set_irq_type,
+};
+
+static void _set_gpio_direction(struct gpio_chip *chip, unsigned offset,
+				int dir)
+{
+	unsigned int base = GPIO_BASE(offset / 32);
+	unsigned int reg;
+
+	reg = __raw_readl(base + GPIO_DIR);
+	if (dir)
+		reg |= 1 << (offset % 32);
+	else
+		reg &= ~(1 << (offset % 32));
+	__raw_writel(reg, base + GPIO_DIR);
+}
+
+static void gemini_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+	unsigned int base = GPIO_BASE(offset / 32);
+
+	if (value)
+		__raw_writel(1 << (offset % 32), base + GPIO_DATA_SET);
+	else
+		__raw_writel(1 << (offset % 32), base + GPIO_DATA_CLR);
+}
+
+static int gemini_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+	unsigned int base = GPIO_BASE(offset / 32);
+
+	return (__raw_readl(base + GPIO_DATA_IN) >> (offset % 32)) & 1;
+}
+
+static int gemini_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+	_set_gpio_direction(chip, offset, 0);
+	return 0;
+}
+
+static int gemini_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
+					int value)
+{
+	_set_gpio_direction(chip, offset, 1);
+	gemini_gpio_set(chip, offset, value);
+	return 0;
+}
+
+static struct gpio_chip gemini_gpio_chip = {
+	.label			= "Gemini",
+	.direction_input	= gemini_gpio_direction_input,
+	.get			= gemini_gpio_get,
+	.direction_output	= gemini_gpio_direction_output,
+	.set			= gemini_gpio_set,
+	.base			= 0,
+	.ngpio			= GPIO_PORT_NUM * 32,
+};
+
+void __init gemini_gpio_init(void)
+{
+	int i, j;
+
+	for (i = 0; i < GPIO_PORT_NUM; i++) {
+		/* disable, unmask and clear all interrupts */
+		__raw_writel(0x0, GPIO_BASE(i) + GPIO_INT_EN);
+		__raw_writel(0x0, GPIO_BASE(i) + GPIO_INT_MASK);
+		__raw_writel(~0x0, GPIO_BASE(i) + GPIO_INT_CLR);
+
+		for (j = GPIO_IRQ_BASE + i * 32;
+		     j < GPIO_IRQ_BASE + (i + 1) * 32; j++) {
+			set_irq_chip(j, &gpio_irq_chip);
+			set_irq_handler(j, handle_edge_irq);
+			set_irq_flags(j, IRQF_VALID);
+		}
+
+		set_irq_chained_handler(IRQ_GPIO(i), gpio_irq_handler);
+		set_irq_data(IRQ_GPIO(i), (void *)i);
+	}
+
+	BUG_ON(gpiochip_add(&gemini_gpio_chip));
+}

arch/arm/mach-gemini/include/mach/gpio.h

+/*
+ * Gemini gpiolib specific defines
+ *
+ * Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
+ *
+ * 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.
+ */
+
+#ifndef __MACH_GPIO_H__
+#define __MACH_GPIO_H__
+
+#include <mach/irqs.h>
+#include <asm-generic/gpio.h>
+
+#define gpio_get_value	__gpio_get_value
+#define gpio_set_value	__gpio_set_value
+#define gpio_cansleep	__gpio_cansleep
+
+#define gpio_to_irq(x)	((x) + GPIO_IRQ_BASE)
+#define irq_to_gpio(x)	((x) - GPIO_IRQ_BASE)
+
+#endif /* __MACH_GPIO_H__ */

arch/arm/mach-gemini/include/mach/irqs.h

@@ -43,8 +43,11 @@
 
 #define NORMAL_IRQ_NUM	32
 
+#define GPIO_IRQ_BASE	NORMAL_IRQ_NUM
+#define GPIO_IRQ_NUM	(3 * 32)
+
 #define ARCH_TIMER_IRQ	IRQ_TIMER2
 
-#define NR_IRQS		NORMAL_IRQ_NUM
+#define NR_IRQS		(NORMAL_IRQ_NUM + GPIO_IRQ_NUM)
 
 #endif /* __MACH_IRQS_H__ */