| /* |
| * arch/sh/boards/mach-x3proto/gpio.c |
| * |
| * Renesas SH-X3 Prototype Baseboard GPIO Support. |
| * |
| * Copyright (C) 2010 Paul Mundt |
| * |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file "COPYING" in the main directory of this archive |
| * for more details. |
| */ |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/init.h> |
| #include <linux/interrupt.h> |
| #include <linux/gpio.h> |
| #include <linux/irq.h> |
| #include <linux/kernel.h> |
| #include <linux/spinlock.h> |
| #include <linux/io.h> |
| #include <mach/ilsel.h> |
| #include <mach/hardware.h> |
| |
| #define KEYCTLR 0xb81c0000 |
| #define KEYOUTR 0xb81c0002 |
| #define KEYDETR 0xb81c0004 |
| |
| static DEFINE_SPINLOCK(x3proto_gpio_lock); |
| static unsigned int x3proto_gpio_irq_map[NR_BASEBOARD_GPIOS] = { 0, }; |
| |
| static int x3proto_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) |
| { |
| unsigned long flags; |
| unsigned int data; |
| |
| spin_lock_irqsave(&x3proto_gpio_lock, flags); |
| data = __raw_readw(KEYCTLR); |
| data |= (1 << gpio); |
| __raw_writew(data, KEYCTLR); |
| spin_unlock_irqrestore(&x3proto_gpio_lock, flags); |
| |
| return 0; |
| } |
| |
| static int x3proto_gpio_get(struct gpio_chip *chip, unsigned gpio) |
| { |
| return !!(__raw_readw(KEYDETR) & (1 << gpio)); |
| } |
| |
| static int x3proto_gpio_to_irq(struct gpio_chip *chip, unsigned gpio) |
| { |
| return x3proto_gpio_irq_map[gpio]; |
| } |
| |
| static void x3proto_gpio_irq_handler(unsigned int irq, struct irq_desc *desc) |
| { |
| struct irq_data *data = irq_get_irq_data(irq); |
| struct irq_chip *chip = irq_data_get_irq_chip(data); |
| unsigned long mask; |
| int pin; |
| |
| chip->irq_mask_ack(data); |
| |
| mask = __raw_readw(KEYDETR); |
| |
| for_each_set_bit(pin, &mask, NR_BASEBOARD_GPIOS) |
| generic_handle_irq(x3proto_gpio_to_irq(NULL, pin)); |
| |
| chip->irq_unmask(data); |
| } |
| |
| struct gpio_chip x3proto_gpio_chip = { |
| .label = "x3proto-gpio", |
| .direction_input = x3proto_gpio_direction_input, |
| .get = x3proto_gpio_get, |
| .to_irq = x3proto_gpio_to_irq, |
| .base = -1, |
| .ngpio = NR_BASEBOARD_GPIOS, |
| }; |
| |
| int __init x3proto_gpio_setup(void) |
| { |
| int ilsel; |
| int ret, i; |
| |
| ilsel = ilsel_enable(ILSEL_KEY); |
| if (unlikely(ilsel < 0)) |
| return ilsel; |
| |
| ret = gpiochip_add(&x3proto_gpio_chip); |
| if (unlikely(ret)) |
| goto err_gpio; |
| |
| for (i = 0; i < NR_BASEBOARD_GPIOS; i++) { |
| unsigned long flags; |
| int irq = create_irq(); |
| |
| if (unlikely(irq < 0)) { |
| ret = -EINVAL; |
| goto err_irq; |
| } |
| |
| spin_lock_irqsave(&x3proto_gpio_lock, flags); |
| x3proto_gpio_irq_map[i] = irq; |
| set_irq_chip_and_handler_name(irq, &dummy_irq_chip, |
| handle_simple_irq, "gpio"); |
| spin_unlock_irqrestore(&x3proto_gpio_lock, flags); |
| } |
| |
| pr_info("registering '%s' support, handling GPIOs %u -> %u, " |
| "bound to IRQ %u\n", |
| x3proto_gpio_chip.label, x3proto_gpio_chip.base, |
| x3proto_gpio_chip.base + x3proto_gpio_chip.ngpio, |
| ilsel); |
| |
| set_irq_chained_handler(ilsel, x3proto_gpio_irq_handler); |
| set_irq_wake(ilsel, 1); |
| |
| return 0; |
| |
| err_irq: |
| for (; i >= 0; --i) |
| if (x3proto_gpio_irq_map[i]) |
| destroy_irq(x3proto_gpio_irq_map[i]); |
| |
| ret = gpiochip_remove(&x3proto_gpio_chip); |
| if (unlikely(ret)) |
| pr_err("Failed deregistering GPIO\n"); |
| |
| err_gpio: |
| synchronize_irq(ilsel); |
| |
| ilsel_disable(ILSEL_KEY); |
| |
| return ret; |
| } |