|  | /* | 
|  | *  linux/drivers/gpio/pl061.c | 
|  | * | 
|  | *  Copyright (C) 2008, 2009 Provigent Ltd. | 
|  | * | 
|  | * 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. | 
|  | * | 
|  | * Driver for the ARM PrimeCell(tm) General Purpose Input/Output (PL061) | 
|  | * | 
|  | * Data sheet: ARM DDI 0190B, September 2000 | 
|  | */ | 
|  | #include <linux/spinlock.h> | 
|  | #include <linux/errno.h> | 
|  | #include <linux/module.h> | 
|  | #include <linux/list.h> | 
|  | #include <linux/io.h> | 
|  | #include <linux/ioport.h> | 
|  | #include <linux/irq.h> | 
|  | #include <linux/bitops.h> | 
|  | #include <linux/workqueue.h> | 
|  | #include <linux/gpio.h> | 
|  | #include <linux/device.h> | 
|  | #include <linux/amba/bus.h> | 
|  | #include <linux/amba/pl061.h> | 
|  |  | 
|  | #define GPIODIR 0x400 | 
|  | #define GPIOIS  0x404 | 
|  | #define GPIOIBE 0x408 | 
|  | #define GPIOIEV 0x40C | 
|  | #define GPIOIE  0x410 | 
|  | #define GPIORIS 0x414 | 
|  | #define GPIOMIS 0x418 | 
|  | #define GPIOIC  0x41C | 
|  |  | 
|  | #define PL061_GPIO_NR	8 | 
|  |  | 
|  | struct pl061_gpio { | 
|  | /* We use a list of pl061_gpio structs for each trigger IRQ in the main | 
|  | * interrupts controller of the system. We need this to support systems | 
|  | * in which more that one PL061s are connected to the same IRQ. The ISR | 
|  | * interates through this list to find the source of the interrupt. | 
|  | */ | 
|  | struct list_head	list; | 
|  |  | 
|  | /* Each of the two spinlocks protects a different set of hardware | 
|  | * regiters and data structurs. This decouples the code of the IRQ from | 
|  | * the GPIO code. This also makes the case of a GPIO routine call from | 
|  | * the IRQ code simpler. | 
|  | */ | 
|  | spinlock_t		lock;		/* GPIO registers */ | 
|  | spinlock_t		irq_lock;	/* IRQ registers */ | 
|  |  | 
|  | void __iomem		*base; | 
|  | unsigned		irq_base; | 
|  | struct gpio_chip	gc; | 
|  | }; | 
|  |  | 
|  | static int pl061_direction_input(struct gpio_chip *gc, unsigned offset) | 
|  | { | 
|  | struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc); | 
|  | unsigned long flags; | 
|  | unsigned char gpiodir; | 
|  |  | 
|  | if (offset >= gc->ngpio) | 
|  | return -EINVAL; | 
|  |  | 
|  | spin_lock_irqsave(&chip->lock, flags); | 
|  | gpiodir = readb(chip->base + GPIODIR); | 
|  | gpiodir &= ~(1 << offset); | 
|  | writeb(gpiodir, chip->base + GPIODIR); | 
|  | spin_unlock_irqrestore(&chip->lock, flags); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int pl061_direction_output(struct gpio_chip *gc, unsigned offset, | 
|  | int value) | 
|  | { | 
|  | struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc); | 
|  | unsigned long flags; | 
|  | unsigned char gpiodir; | 
|  |  | 
|  | if (offset >= gc->ngpio) | 
|  | return -EINVAL; | 
|  |  | 
|  | spin_lock_irqsave(&chip->lock, flags); | 
|  | writeb(!!value << offset, chip->base + (1 << (offset + 2))); | 
|  | gpiodir = readb(chip->base + GPIODIR); | 
|  | gpiodir |= 1 << offset; | 
|  | writeb(gpiodir, chip->base + GPIODIR); | 
|  | spin_unlock_irqrestore(&chip->lock, flags); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int pl061_get_value(struct gpio_chip *gc, unsigned offset) | 
|  | { | 
|  | struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc); | 
|  |  | 
|  | return !!readb(chip->base + (1 << (offset + 2))); | 
|  | } | 
|  |  | 
|  | static void pl061_set_value(struct gpio_chip *gc, unsigned offset, int value) | 
|  | { | 
|  | struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc); | 
|  |  | 
|  | writeb(!!value << offset, chip->base + (1 << (offset + 2))); | 
|  | } | 
|  |  | 
|  | static int pl061_to_irq(struct gpio_chip *gc, unsigned offset) | 
|  | { | 
|  | struct pl061_gpio *chip = container_of(gc, struct pl061_gpio, gc); | 
|  |  | 
|  | if (chip->irq_base == (unsigned) -1) | 
|  | return -EINVAL; | 
|  |  | 
|  | return chip->irq_base + offset; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * PL061 GPIO IRQ | 
|  | */ | 
|  | static void pl061_irq_disable(unsigned irq) | 
|  | { | 
|  | struct pl061_gpio *chip = get_irq_chip_data(irq); | 
|  | int offset = irq - chip->irq_base; | 
|  | unsigned long flags; | 
|  | u8 gpioie; | 
|  |  | 
|  | spin_lock_irqsave(&chip->irq_lock, flags); | 
|  | gpioie = readb(chip->base + GPIOIE); | 
|  | gpioie &= ~(1 << offset); | 
|  | writeb(gpioie, chip->base + GPIOIE); | 
|  | spin_unlock_irqrestore(&chip->irq_lock, flags); | 
|  | } | 
|  |  | 
|  | static void pl061_irq_enable(unsigned irq) | 
|  | { | 
|  | struct pl061_gpio *chip = get_irq_chip_data(irq); | 
|  | int offset = irq - chip->irq_base; | 
|  | unsigned long flags; | 
|  | u8 gpioie; | 
|  |  | 
|  | spin_lock_irqsave(&chip->irq_lock, flags); | 
|  | gpioie = readb(chip->base + GPIOIE); | 
|  | gpioie |= 1 << offset; | 
|  | writeb(gpioie, chip->base + GPIOIE); | 
|  | spin_unlock_irqrestore(&chip->irq_lock, flags); | 
|  | } | 
|  |  | 
|  | static int pl061_irq_type(unsigned irq, unsigned trigger) | 
|  | { | 
|  | struct pl061_gpio *chip = get_irq_chip_data(irq); | 
|  | int offset = irq - chip->irq_base; | 
|  | unsigned long flags; | 
|  | u8 gpiois, gpioibe, gpioiev; | 
|  |  | 
|  | if (offset < 0 || offset > PL061_GPIO_NR) | 
|  | return -EINVAL; | 
|  |  | 
|  | spin_lock_irqsave(&chip->irq_lock, flags); | 
|  |  | 
|  | gpioiev = readb(chip->base + GPIOIEV); | 
|  |  | 
|  | gpiois = readb(chip->base + GPIOIS); | 
|  | if (trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) { | 
|  | gpiois |= 1 << offset; | 
|  | if (trigger & IRQ_TYPE_LEVEL_HIGH) | 
|  | gpioiev |= 1 << offset; | 
|  | else | 
|  | gpioiev &= ~(1 << offset); | 
|  | } else | 
|  | gpiois &= ~(1 << offset); | 
|  | writeb(gpiois, chip->base + GPIOIS); | 
|  |  | 
|  | gpioibe = readb(chip->base + GPIOIBE); | 
|  | if ((trigger & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) | 
|  | gpioibe |= 1 << offset; | 
|  | else { | 
|  | gpioibe &= ~(1 << offset); | 
|  | if (trigger & IRQ_TYPE_EDGE_RISING) | 
|  | gpioiev |= 1 << offset; | 
|  | else | 
|  | gpioiev &= ~(1 << offset); | 
|  | } | 
|  | writeb(gpioibe, chip->base + GPIOIBE); | 
|  |  | 
|  | writeb(gpioiev, chip->base + GPIOIEV); | 
|  |  | 
|  | spin_unlock_irqrestore(&chip->irq_lock, flags); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static struct irq_chip pl061_irqchip = { | 
|  | .name		= "GPIO", | 
|  | .enable		= pl061_irq_enable, | 
|  | .disable	= pl061_irq_disable, | 
|  | .set_type	= pl061_irq_type, | 
|  | }; | 
|  |  | 
|  | static void pl061_irq_handler(unsigned irq, struct irq_desc *desc) | 
|  | { | 
|  | struct list_head *chip_list = get_irq_chip_data(irq); | 
|  | struct list_head *ptr; | 
|  | struct pl061_gpio *chip; | 
|  |  | 
|  | desc->chip->ack(irq); | 
|  | list_for_each(ptr, chip_list) { | 
|  | unsigned long pending; | 
|  | int offset; | 
|  |  | 
|  | chip = list_entry(ptr, struct pl061_gpio, list); | 
|  | pending = readb(chip->base + GPIOMIS); | 
|  | writeb(pending, chip->base + GPIOIC); | 
|  |  | 
|  | if (pending == 0) | 
|  | continue; | 
|  |  | 
|  | for_each_bit(offset, &pending, PL061_GPIO_NR) | 
|  | generic_handle_irq(pl061_to_irq(&chip->gc, offset)); | 
|  | } | 
|  | desc->chip->unmask(irq); | 
|  | } | 
|  |  | 
|  | static int __init pl061_probe(struct amba_device *dev, struct amba_id *id) | 
|  | { | 
|  | struct pl061_platform_data *pdata; | 
|  | struct pl061_gpio *chip; | 
|  | struct list_head *chip_list; | 
|  | int ret, irq, i; | 
|  | static DECLARE_BITMAP(init_irq, NR_IRQS); | 
|  |  | 
|  | pdata = dev->dev.platform_data; | 
|  | if (pdata == NULL) | 
|  | return -ENODEV; | 
|  |  | 
|  | chip = kzalloc(sizeof(*chip), GFP_KERNEL); | 
|  | if (chip == NULL) | 
|  | return -ENOMEM; | 
|  |  | 
|  | if (!request_mem_region(dev->res.start, | 
|  | resource_size(&dev->res), "pl061")) { | 
|  | ret = -EBUSY; | 
|  | goto free_mem; | 
|  | } | 
|  |  | 
|  | chip->base = ioremap(dev->res.start, resource_size(&dev->res)); | 
|  | if (chip->base == NULL) { | 
|  | ret = -ENOMEM; | 
|  | goto release_region; | 
|  | } | 
|  |  | 
|  | spin_lock_init(&chip->lock); | 
|  | spin_lock_init(&chip->irq_lock); | 
|  | INIT_LIST_HEAD(&chip->list); | 
|  |  | 
|  | chip->gc.direction_input = pl061_direction_input; | 
|  | chip->gc.direction_output = pl061_direction_output; | 
|  | chip->gc.get = pl061_get_value; | 
|  | chip->gc.set = pl061_set_value; | 
|  | chip->gc.to_irq = pl061_to_irq; | 
|  | chip->gc.base = pdata->gpio_base; | 
|  | chip->gc.ngpio = PL061_GPIO_NR; | 
|  | chip->gc.label = dev_name(&dev->dev); | 
|  | chip->gc.dev = &dev->dev; | 
|  | chip->gc.owner = THIS_MODULE; | 
|  |  | 
|  | chip->irq_base = pdata->irq_base; | 
|  |  | 
|  | ret = gpiochip_add(&chip->gc); | 
|  | if (ret) | 
|  | goto iounmap; | 
|  |  | 
|  | /* | 
|  | * irq_chip support | 
|  | */ | 
|  |  | 
|  | if (chip->irq_base == (unsigned) -1) | 
|  | return 0; | 
|  |  | 
|  | writeb(0, chip->base + GPIOIE); /* disable irqs */ | 
|  | irq = dev->irq[0]; | 
|  | if (irq < 0) { | 
|  | ret = -ENODEV; | 
|  | goto iounmap; | 
|  | } | 
|  | set_irq_chained_handler(irq, pl061_irq_handler); | 
|  | if (!test_and_set_bit(irq, init_irq)) { /* list initialized? */ | 
|  | chip_list = kmalloc(sizeof(*chip_list), GFP_KERNEL); | 
|  | if (chip_list == NULL) { | 
|  | clear_bit(irq, init_irq); | 
|  | ret = -ENOMEM; | 
|  | goto iounmap; | 
|  | } | 
|  | INIT_LIST_HEAD(chip_list); | 
|  | set_irq_chip_data(irq, chip_list); | 
|  | } else | 
|  | chip_list = get_irq_chip_data(irq); | 
|  | list_add(&chip->list, chip_list); | 
|  |  | 
|  | for (i = 0; i < PL061_GPIO_NR; i++) { | 
|  | if (pdata->directions & (1 << i)) | 
|  | pl061_direction_output(&chip->gc, i, | 
|  | pdata->values & (1 << i)); | 
|  | else | 
|  | pl061_direction_input(&chip->gc, i); | 
|  |  | 
|  | set_irq_chip(i+chip->irq_base, &pl061_irqchip); | 
|  | set_irq_handler(i+chip->irq_base, handle_simple_irq); | 
|  | set_irq_flags(i+chip->irq_base, IRQF_VALID); | 
|  | set_irq_chip_data(i+chip->irq_base, chip); | 
|  | } | 
|  |  | 
|  | return 0; | 
|  |  | 
|  | iounmap: | 
|  | iounmap(chip->base); | 
|  | release_region: | 
|  | release_mem_region(dev->res.start, resource_size(&dev->res)); | 
|  | free_mem: | 
|  | kfree(chip); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static struct amba_id pl061_ids[] __initdata = { | 
|  | { | 
|  | .id	= 0x00041061, | 
|  | .mask	= 0x000fffff, | 
|  | }, | 
|  | { 0, 0 }, | 
|  | }; | 
|  |  | 
|  | static struct amba_driver pl061_gpio_driver = { | 
|  | .drv = { | 
|  | .name	= "pl061_gpio", | 
|  | }, | 
|  | .id_table	= pl061_ids, | 
|  | .probe		= pl061_probe, | 
|  | }; | 
|  |  | 
|  | static int __init pl061_gpio_init(void) | 
|  | { | 
|  | return amba_driver_register(&pl061_gpio_driver); | 
|  | } | 
|  | subsys_initcall(pl061_gpio_init); | 
|  |  | 
|  | MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>"); | 
|  | MODULE_DESCRIPTION("PL061 GPIO driver"); | 
|  | MODULE_LICENSE("GPL"); |