diff options
Diffstat (limited to 'arch/arm/mach-ep93xx/gpio.c')
| -rw-r--r-- | arch/arm/mach-ep93xx/gpio.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/arch/arm/mach-ep93xx/gpio.c b/arch/arm/mach-ep93xx/gpio.c new file mode 100644 index 000000000000..dc2e4c00d989 --- /dev/null +++ b/arch/arm/mach-ep93xx/gpio.c @@ -0,0 +1,158 @@ +/* + * linux/arch/arm/mach-ep93xx/gpio.c + * + * Generic EP93xx GPIO handling + * + * Copyright (c) 2008 Ryan Mallon <ryan@bluewatersys.com> + * + * Based on code originally from: + * linux/arch/arm/mach-ep93xx/core.c + * + * 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 <linux/init.h> +#include <linux/module.h> +#include <linux/seq_file.h> + +#include <asm/arch/ep93xx-regs.h> +#include <asm/io.h> +#include <asm/gpio.h> + +struct ep93xx_gpio_chip { + struct gpio_chip chip; + + unsigned int data_reg; + unsigned int data_dir_reg; +}; + +#define to_ep93xx_gpio_chip(c) container_of(c, struct ep93xx_gpio_chip, chip) + +/* From core.c */ +extern void ep93xx_gpio_int_mask(unsigned line); +extern void ep93xx_gpio_update_int_params(unsigned port); + +static int ep93xx_gpio_direction_input(struct gpio_chip *chip, unsigned offset) +{ + struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip); + unsigned long flags; + u8 v; + + local_irq_save(flags); + v = __raw_readb(ep93xx_chip->data_dir_reg); + v &= ~(1 << offset); + __raw_writeb(v, ep93xx_chip->data_dir_reg); + local_irq_restore(flags); + + return 0; +} + +static int ep93xx_gpio_direction_output(struct gpio_chip *chip, + unsigned offset, int val) +{ + struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip); + unsigned long flags; + int line; + u8 v; + + local_irq_save(flags); + + /* Set the value */ + v = __raw_readb(ep93xx_chip->data_reg); + if (val) + v |= (1 << offset); + else + v &= ~(1 << offset); + __raw_writeb(v, ep93xx_chip->data_reg); + + /* Drive as an output */ + line = chip->base + offset; + if (line <= EP93XX_GPIO_LINE_MAX_IRQ) { + /* Ports A/B/F */ + ep93xx_gpio_int_mask(line); + ep93xx_gpio_update_int_params(line >> 3); + } + + v = __raw_readb(ep93xx_chip->data_dir_reg); + v |= (1 << offset); + __raw_writeb(v, ep93xx_chip->data_dir_reg); + + local_irq_restore(flags); + + return 0; +} + +static int ep93xx_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip); + + return !!(__raw_readb(ep93xx_chip->data_reg) & (1 << offset)); +} + +static void ep93xx_gpio_set(struct gpio_chip *chip, unsigned offset, int val) +{ + struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip); + unsigned long flags; + u8 v; + + local_irq_save(flags); + v = __raw_readb(ep93xx_chip->data_reg); + if (val) + v |= (1 << offset); + else + v &= ~(1 << offset); + __raw_writeb(v, ep93xx_chip->data_reg); + local_irq_restore(flags); +} + +static void ep93xx_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip) +{ + struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip); + u8 data_reg, data_dir_reg; + int i; + + data_reg = __raw_readb(ep93xx_chip->data_reg); + data_dir_reg = __raw_readb(ep93xx_chip->data_dir_reg); + + for (i = 0; i < chip->ngpio; i++) + seq_printf(s, "GPIO %s%d: %s %s\n", chip->label, i, + (data_reg & (1 << i)) ? "set" : "clear", + (data_dir_reg & (1 << i)) ? "out" : "in"); +} + +#define EP93XX_GPIO_BANK(name, dr, ddr, base_gpio) \ + { \ + .chip = { \ + .label = name, \ + .direction_input = ep93xx_gpio_direction_input, \ + .direction_output = ep93xx_gpio_direction_output, \ + .get = ep93xx_gpio_get, \ + .set = ep93xx_gpio_set, \ + .dbg_show = ep93xx_gpio_dbg_show, \ + .base = base_gpio, \ + .ngpio = 8, \ + }, \ + .data_reg = EP93XX_GPIO_REG(dr), \ + .data_dir_reg = EP93XX_GPIO_REG(ddr), \ + } + +static struct ep93xx_gpio_chip ep93xx_gpio_banks[] = { + EP93XX_GPIO_BANK("A", 0x00, 0x10, 0), + EP93XX_GPIO_BANK("B", 0x04, 0x14, 8), + EP93XX_GPIO_BANK("C", 0x30, 0x34, 40), + EP93XX_GPIO_BANK("D", 0x0c, 0x1c, 24), + EP93XX_GPIO_BANK("E", 0x20, 0x24, 32), + EP93XX_GPIO_BANK("F", 0x08, 0x18, 16), + EP93XX_GPIO_BANK("G", 0x38, 0x3c, 48), + EP93XX_GPIO_BANK("H", 0x40, 0x44, 56), +}; + +void __init ep93xx_gpio_init(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(ep93xx_gpio_banks); i++) + gpiochip_add(&ep93xx_gpio_banks[i].chip); +} |