diff options
Diffstat (limited to 'arch/arm/mach-gemini/gpio.c')
| -rw-r--r-- | arch/arm/mach-gemini/gpio.c | 232 |
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 0000000..e726385 --- /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)); +} |