diff options
Diffstat (limited to 'arch/arm/mach-davinci/gpio.c')
-rw-r--r-- | arch/arm/mach-davinci/gpio.c | 292 |
1 files changed, 292 insertions, 0 deletions
diff --git a/arch/arm/mach-davinci/gpio.c b/arch/arm/mach-davinci/gpio.c new file mode 100644 index 0000000..b49e9d0 --- /dev/null +++ b/arch/arm/mach-davinci/gpio.c @@ -0,0 +1,292 @@ +/* + * TI DaVinci GPIO Support + * + * Copyright (c) 2006-2007 David Brownell + * Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com> + * + * 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/errno.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/bitops.h> + +#include <mach/irqs.h> +#include <mach/hardware.h> +#include <mach/gpio.h> + +#include <asm/mach/irq.h> + + +static DEFINE_SPINLOCK(gpio_lock); + +struct davinci_gpio { + struct gpio_chip chip; + struct gpio_controller *__iomem regs; +}; + +static struct davinci_gpio chips[DIV_ROUND_UP(DAVINCI_N_GPIO, 32)]; + + +/* create a non-inlined version */ +static struct gpio_controller *__iomem __init gpio2controller(unsigned gpio) +{ + return __gpio_to_controller(gpio); +} + + +/*--------------------------------------------------------------------------*/ + +/* + * board setup code *MUST* set PINMUX0 and PINMUX1 as + * needed, and enable the GPIO clock. + */ + +static int davinci_direction_in(struct gpio_chip *chip, unsigned offset) +{ + struct davinci_gpio *d = container_of(chip, struct davinci_gpio, chip); + struct gpio_controller *__iomem g = d->regs; + u32 temp; + + spin_lock(&gpio_lock); + temp = __raw_readl(&g->dir); + temp |= (1 << offset); + __raw_writel(temp, &g->dir); + spin_unlock(&gpio_lock); + + return 0; +} + +/* + * Read the pin's value (works even if it's set up as output); + * returns zero/nonzero. + * + * Note that changes are synched to the GPIO clock, so reading values back + * right after you've set them may give old values. + */ +static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + struct davinci_gpio *d = container_of(chip, struct davinci_gpio, chip); + struct gpio_controller *__iomem g = d->regs; + + return (1 << offset) & __raw_readl(&g->in_data); +} + +static int +davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value) +{ + struct davinci_gpio *d = container_of(chip, struct davinci_gpio, chip); + struct gpio_controller *__iomem g = d->regs; + u32 temp; + u32 mask = 1 << offset; + + spin_lock(&gpio_lock); + temp = __raw_readl(&g->dir); + temp &= ~mask; + __raw_writel(mask, value ? &g->set_data : &g->clr_data); + __raw_writel(temp, &g->dir); + spin_unlock(&gpio_lock); + return 0; +} + +/* + * Assuming the pin is muxed as a gpio output, set its output value. + */ +static void +davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value) +{ + struct davinci_gpio *d = container_of(chip, struct davinci_gpio, chip); + struct gpio_controller *__iomem g = d->regs; + + __raw_writel((1 << offset), value ? &g->set_data : &g->clr_data); +} + +static int __init davinci_gpio_setup(void) +{ + int i, base; + + for (i = 0, base = 0; + i < ARRAY_SIZE(chips); + i++, base += 32) { + chips[i].chip.label = "DaVinci"; + + chips[i].chip.direction_input = davinci_direction_in; + chips[i].chip.get = davinci_gpio_get; + chips[i].chip.direction_output = davinci_direction_out; + chips[i].chip.set = davinci_gpio_set; + + chips[i].chip.base = base; + chips[i].chip.ngpio = DAVINCI_N_GPIO - base; + if (chips[i].chip.ngpio > 32) + chips[i].chip.ngpio = 32; + + chips[i].regs = gpio2controller(base); + + gpiochip_add(&chips[i].chip); + } + + return 0; +} +pure_initcall(davinci_gpio_setup); + +/*--------------------------------------------------------------------------*/ +/* + * We expect irqs will normally be set up as input pins, but they can also be + * used as output pins ... which is convenient for testing. + * + * NOTE: GPIO0..GPIO7 also have direct INTC hookups, which work in addition + * to their GPIOBNK0 irq (but with a bit less overhead). But we don't have + * a good way to hook those up ... + * + * All those INTC hookups (GPIO0..GPIO7 plus five IRQ banks) can also + * serve as EDMA event triggers. + */ + +static void gpio_irq_disable(unsigned irq) +{ + struct gpio_controller *__iomem g = get_irq_chip_data(irq); + u32 mask = __gpio_mask(irq_to_gpio(irq)); + + __raw_writel(mask, &g->clr_falling); + __raw_writel(mask, &g->clr_rising); +} + +static void gpio_irq_enable(unsigned irq) +{ + struct gpio_controller *__iomem g = get_irq_chip_data(irq); + u32 mask = __gpio_mask(irq_to_gpio(irq)); + + if (irq_desc[irq].status & IRQ_TYPE_EDGE_FALLING) + __raw_writel(mask, &g->set_falling); + if (irq_desc[irq].status & IRQ_TYPE_EDGE_RISING) + __raw_writel(mask, &g->set_rising); +} + +static int gpio_irq_type(unsigned irq, unsigned trigger) +{ + struct gpio_controller *__iomem g = get_irq_chip_data(irq); + u32 mask = __gpio_mask(irq_to_gpio(irq)); + + if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)) + return -EINVAL; + + irq_desc[irq].status &= ~IRQ_TYPE_SENSE_MASK; + irq_desc[irq].status |= trigger; + + __raw_writel(mask, (trigger & IRQ_TYPE_EDGE_FALLING) + ? &g->set_falling : &g->clr_falling); + __raw_writel(mask, (trigger & IRQ_TYPE_EDGE_RISING) + ? &g->set_rising : &g->clr_rising); + return 0; +} + +static struct irq_chip gpio_irqchip = { + .name = "GPIO", + .enable = gpio_irq_enable, + .disable = gpio_irq_disable, + .set_type = gpio_irq_type, +}; + +static void +gpio_irq_handler(unsigned irq, struct irq_desc *desc) +{ + struct gpio_controller *__iomem g = get_irq_chip_data(irq); + u32 mask = 0xffff; + + /* we only care about one bank */ + if (irq & 1) + mask <<= 16; + + /* temporarily mask (level sensitive) parent IRQ */ + desc->chip->ack(irq); + while (1) { + u32 status; + int n; + int res; + + /* ack any irqs */ + status = __raw_readl(&g->intstat) & mask; + if (!status) + break; + __raw_writel(status, &g->intstat); + if (irq & 1) + status >>= 16; + + /* now demux them to the right lowlevel handler */ + n = (int)get_irq_data(irq); + while (status) { + res = ffs(status); + n += res; + generic_handle_irq(n - 1); + status >>= res; + } + } + desc->chip->unmask(irq); + /* now it may re-trigger */ +} + +/* + * NOTE: for suspend/resume, probably best to make a sysdev (and class) + * with its suspend/resume calls hooking into the results of the set_wake() + * calls ... so if no gpios are wakeup events the clock can be disabled, + * with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0 + * can be set appropriately for GPIOV33 pins. + */ + +static int __init davinci_gpio_irq_setup(void) +{ + unsigned gpio, irq, bank; + struct clk *clk; + + clk = clk_get(NULL, "gpio"); + if (IS_ERR(clk)) { + printk(KERN_ERR "Error %ld getting gpio clock?\n", + PTR_ERR(clk)); + return 0; + } + + clk_enable(clk); + + for (gpio = 0, irq = gpio_to_irq(0), bank = IRQ_GPIOBNK0; + gpio < DAVINCI_N_GPIO; bank++) { + struct gpio_controller *__iomem g = gpio2controller(gpio); + unsigned i; + + __raw_writel(~0, &g->clr_falling); + __raw_writel(~0, &g->clr_rising); + + /* set up all irqs in this bank */ + set_irq_chained_handler(bank, gpio_irq_handler); + set_irq_chip_data(bank, g); + set_irq_data(bank, (void *)irq); + + for (i = 0; i < 16 && gpio < DAVINCI_N_GPIO; + i++, irq++, gpio++) { + set_irq_chip(irq, &gpio_irqchip); + set_irq_chip_data(irq, g); + set_irq_handler(irq, handle_simple_irq); + set_irq_flags(irq, IRQF_VALID); + } + } + + /* BINTEN -- per-bank interrupt enable. genirq would also let these + * bits be set/cleared dynamically. + */ + __raw_writel(0x1f, (void *__iomem) + IO_ADDRESS(DAVINCI_GPIO_BASE + 0x08)); + + printk(KERN_INFO "DaVinci: %d gpio irqs\n", irq - gpio_to_irq(0)); + + return 0; +} + +arch_initcall(davinci_gpio_irq_setup); |