diff options
Diffstat (limited to 'arch/sh/boards/mach-x3proto/gpio.c')
-rw-r--r-- | arch/sh/boards/mach-x3proto/gpio.c | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/arch/sh/boards/mach-x3proto/gpio.c b/arch/sh/boards/mach-x3proto/gpio.c new file mode 100644 index 000000000..cea88b0ef --- /dev/null +++ b/arch/sh/boards/mach-x3proto/gpio.c @@ -0,0 +1,139 @@ +/* + * arch/sh/boards/mach-x3proto/gpio.c + * + * Renesas SH-X3 Prototype Baseboard GPIO Support. + * + * Copyright (C) 2010 - 2012 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/driver.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/spinlock.h> +#include <linux/irqdomain.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 struct irq_domain *x3proto_irq_domain; + +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) +{ + int virq; + + if (gpio < chip->ngpio) + virq = irq_create_mapping(x3proto_irq_domain, gpio); + else + virq = -ENXIO; + + return virq; +} + +static void x3proto_gpio_irq_handler(struct irq_desc *desc) +{ + struct irq_data *data = irq_desc_get_irq_data(desc); + 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(irq_linear_revmap(x3proto_irq_domain, 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, +}; + +static int x3proto_gpio_irq_map(struct irq_domain *domain, unsigned int virq, + irq_hw_number_t hwirq) +{ + irq_set_chip_and_handler_name(virq, &dummy_irq_chip, handle_simple_irq, + "gpio"); + + return 0; +} + +static struct irq_domain_ops x3proto_gpio_irq_ops = { + .map = x3proto_gpio_irq_map, + .xlate = irq_domain_xlate_twocell, +}; + +int __init x3proto_gpio_setup(void) +{ + int ilsel, ret; + + ilsel = ilsel_enable(ILSEL_KEY); + if (unlikely(ilsel < 0)) + return ilsel; + + ret = gpiochip_add_data(&x3proto_gpio_chip, NULL); + if (unlikely(ret)) + goto err_gpio; + + x3proto_irq_domain = irq_domain_add_linear(NULL, NR_BASEBOARD_GPIOS, + &x3proto_gpio_irq_ops, NULL); + if (unlikely(!x3proto_irq_domain)) + goto err_irq; + + 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); + + irq_set_chained_handler(ilsel, x3proto_gpio_irq_handler); + irq_set_irq_wake(ilsel, 1); + + return 0; + +err_irq: + gpiochip_remove(&x3proto_gpio_chip); + ret = 0; +err_gpio: + synchronize_irq(ilsel); + + ilsel_disable(ILSEL_KEY); + + return ret; +} |