diff options
Diffstat (limited to 'drivers/gpio/gpio-sa1100.c')
| -rw-r--r-- | drivers/gpio/gpio-sa1100.c | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-sa1100.c b/drivers/gpio/gpio-sa1100.c new file mode 100644 index 000000000..bec397a60 --- /dev/null +++ b/drivers/gpio/gpio-sa1100.c @@ -0,0 +1,267 @@ +/* + * linux/arch/arm/mach-sa1100/gpio.c + * + * Generic SA-1100 GPIO handling + * + * 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/gpio.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/io.h> +#include <linux/syscore_ops.h> +#include <mach/hardware.h> +#include <mach/irqs.h> + +static int sa1100_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + return GPLR & GPIO_GPIO(offset); +} + +static void sa1100_gpio_set(struct gpio_chip *chip, unsigned offset, int value) +{ + if (value) + GPSR = GPIO_GPIO(offset); + else + GPCR = GPIO_GPIO(offset); +} + +static int sa1100_direction_input(struct gpio_chip *chip, unsigned offset) +{ + unsigned long flags; + + local_irq_save(flags); + GPDR &= ~GPIO_GPIO(offset); + local_irq_restore(flags); + return 0; +} + +static int sa1100_direction_output(struct gpio_chip *chip, unsigned offset, int value) +{ + unsigned long flags; + + local_irq_save(flags); + sa1100_gpio_set(chip, offset, value); + GPDR |= GPIO_GPIO(offset); + local_irq_restore(flags); + return 0; +} + +static int sa1100_to_irq(struct gpio_chip *chip, unsigned offset) +{ + return IRQ_GPIO0 + offset; +} + +static struct gpio_chip sa1100_gpio_chip = { + .label = "gpio", + .direction_input = sa1100_direction_input, + .direction_output = sa1100_direction_output, + .set = sa1100_gpio_set, + .get = sa1100_gpio_get, + .to_irq = sa1100_to_irq, + .base = 0, + .ngpio = GPIO_MAX + 1, +}; + +/* + * SA1100 GPIO edge detection for IRQs: + * IRQs are generated on Falling-Edge, Rising-Edge, or both. + * Use this instead of directly setting GRER/GFER. + */ +static int GPIO_IRQ_rising_edge; +static int GPIO_IRQ_falling_edge; +static int GPIO_IRQ_mask; + +static int sa1100_gpio_type(struct irq_data *d, unsigned int type) +{ + unsigned int mask; + + mask = BIT(d->hwirq); + + if (type == IRQ_TYPE_PROBE) { + if ((GPIO_IRQ_rising_edge | GPIO_IRQ_falling_edge) & mask) + return 0; + type = IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING; + } + + if (type & IRQ_TYPE_EDGE_RISING) + GPIO_IRQ_rising_edge |= mask; + else + GPIO_IRQ_rising_edge &= ~mask; + if (type & IRQ_TYPE_EDGE_FALLING) + GPIO_IRQ_falling_edge |= mask; + else + GPIO_IRQ_falling_edge &= ~mask; + + GRER = GPIO_IRQ_rising_edge & GPIO_IRQ_mask; + GFER = GPIO_IRQ_falling_edge & GPIO_IRQ_mask; + + return 0; +} + +/* + * GPIO IRQs must be acknowledged. + */ +static void sa1100_gpio_ack(struct irq_data *d) +{ + GEDR = BIT(d->hwirq); +} + +static void sa1100_gpio_mask(struct irq_data *d) +{ + unsigned int mask = BIT(d->hwirq); + + GPIO_IRQ_mask &= ~mask; + + GRER &= ~mask; + GFER &= ~mask; +} + +static void sa1100_gpio_unmask(struct irq_data *d) +{ + unsigned int mask = BIT(d->hwirq); + + GPIO_IRQ_mask |= mask; + + GRER = GPIO_IRQ_rising_edge & GPIO_IRQ_mask; + GFER = GPIO_IRQ_falling_edge & GPIO_IRQ_mask; +} + +static int sa1100_gpio_wake(struct irq_data *d, unsigned int on) +{ + if (on) + PWER |= BIT(d->hwirq); + else + PWER &= ~BIT(d->hwirq); + return 0; +} + +/* + * This is for GPIO IRQs + */ +static struct irq_chip sa1100_gpio_irq_chip = { + .name = "GPIO", + .irq_ack = sa1100_gpio_ack, + .irq_mask = sa1100_gpio_mask, + .irq_unmask = sa1100_gpio_unmask, + .irq_set_type = sa1100_gpio_type, + .irq_set_wake = sa1100_gpio_wake, +}; + +static int sa1100_gpio_irqdomain_map(struct irq_domain *d, + unsigned int irq, irq_hw_number_t hwirq) +{ + irq_set_chip_and_handler(irq, &sa1100_gpio_irq_chip, + handle_edge_irq); + set_irq_flags(irq, IRQF_VALID | IRQF_PROBE); + + return 0; +} + +static struct irq_domain_ops sa1100_gpio_irqdomain_ops = { + .map = sa1100_gpio_irqdomain_map, + .xlate = irq_domain_xlate_onetwocell, +}; + +static struct irq_domain *sa1100_gpio_irqdomain; + +/* + * IRQ 0-11 (GPIO) handler. We enter here with the + * irq_controller_lock held, and IRQs disabled. Decode the IRQ + * and call the handler. + */ +static void +sa1100_gpio_handler(unsigned int irq, struct irq_desc *desc) +{ + unsigned int mask; + + mask = GEDR; + do { + /* + * clear down all currently active IRQ sources. + * We will be processing them all. + */ + GEDR = mask; + + irq = IRQ_GPIO0; + do { + if (mask & 1) + generic_handle_irq(irq); + mask >>= 1; + irq++; + } while (mask); + + mask = GEDR; + } while (mask); +} + +static int sa1100_gpio_suspend(void) +{ + /* + * Set the appropriate edges for wakeup. + */ + GRER = PWER & GPIO_IRQ_rising_edge; + GFER = PWER & GPIO_IRQ_falling_edge; + + /* + * Clear any pending GPIO interrupts. + */ + GEDR = GEDR; + + return 0; +} + +static void sa1100_gpio_resume(void) +{ + GRER = GPIO_IRQ_rising_edge & GPIO_IRQ_mask; + GFER = GPIO_IRQ_falling_edge & GPIO_IRQ_mask; +} + +static struct syscore_ops sa1100_gpio_syscore_ops = { + .suspend = sa1100_gpio_suspend, + .resume = sa1100_gpio_resume, +}; + +static int __init sa1100_gpio_init_devicefs(void) +{ + register_syscore_ops(&sa1100_gpio_syscore_ops); + return 0; +} + +device_initcall(sa1100_gpio_init_devicefs); + +void __init sa1100_init_gpio(void) +{ + /* clear all GPIO edge detects */ + GFER = 0; + GRER = 0; + GEDR = -1; + + gpiochip_add(&sa1100_gpio_chip); + + sa1100_gpio_irqdomain = irq_domain_add_simple(NULL, + 28, IRQ_GPIO0, + &sa1100_gpio_irqdomain_ops, NULL); + + /* + * Install handlers for GPIO 0-10 edge detect interrupts + */ + irq_set_chained_handler(IRQ_GPIO0_SC, sa1100_gpio_handler); + irq_set_chained_handler(IRQ_GPIO1_SC, sa1100_gpio_handler); + irq_set_chained_handler(IRQ_GPIO2_SC, sa1100_gpio_handler); + irq_set_chained_handler(IRQ_GPIO3_SC, sa1100_gpio_handler); + irq_set_chained_handler(IRQ_GPIO4_SC, sa1100_gpio_handler); + irq_set_chained_handler(IRQ_GPIO5_SC, sa1100_gpio_handler); + irq_set_chained_handler(IRQ_GPIO6_SC, sa1100_gpio_handler); + irq_set_chained_handler(IRQ_GPIO7_SC, sa1100_gpio_handler); + irq_set_chained_handler(IRQ_GPIO8_SC, sa1100_gpio_handler); + irq_set_chained_handler(IRQ_GPIO9_SC, sa1100_gpio_handler); + irq_set_chained_handler(IRQ_GPIO10_SC, sa1100_gpio_handler); + /* + * Install handler for GPIO 11-27 edge detect interrupts + */ + irq_set_chained_handler(IRQ_GPIO11_27, sa1100_gpio_handler); + +} |