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authorPaulius Zaleckas <paulius.zaleckas@teltonika.lt>2009-03-26 09:06:27 +0100
committerPaulius Zaleckas <paulius.zaleckas@teltonika.lt>2009-03-26 09:06:27 +0100
commit1df621ae2f3b03d557d962a7afec2b1d04558986 (patch)
tree3de532bd034f01a73d4c04e297afa69835886708 /arch/arm/mach-gemini/gpio.c
parentMAINTAINERS: add myself as Gemini architecture maintainer (diff)
downloadlinux-1df621ae2f3b03d557d962a7afec2b1d04558986.tar.xz
linux-1df621ae2f3b03d557d962a7afec2b1d04558986.zip
Gemini: gpiolib based GPIO support v2
v2: - update copyrights Signed-off-by: Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
Diffstat (limited to 'arch/arm/mach-gemini/gpio.c')
-rw-r--r--arch/arm/mach-gemini/gpio.c232
1 files changed, 232 insertions, 0 deletions
diff --git a/arch/arm/mach-gemini/gpio.c b/arch/arm/mach-gemini/gpio.c
new file mode 100644
index 000000000000..e7263854bc7b
--- /dev/null
+++ b/arch/arm/mach-gemini/gpio.c
@@ -0,0 +1,232 @@
+/*
+ * 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));
+}