| /* |
| * 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> |
| #include <linux/slab.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); |
| |
| /* |
| * gpio value is set again, because pl061 doesn't allow to set value of |
| * a gpio pin before configuring it in OUT mode. |
| */ |
| writeb(!!value << offset, chip->base + (1 << (offset + 2))); |
| 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(struct irq_data *d) |
| { |
| struct pl061_gpio *chip = irq_data_get_irq_chip_data(d); |
| int offset = d->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(struct irq_data *d) |
| { |
| struct pl061_gpio *chip = irq_data_get_irq_chip_data(d); |
| int offset = d->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(struct irq_data *d, unsigned trigger) |
| { |
| struct pl061_gpio *chip = irq_data_get_irq_chip_data(d); |
| int offset = d->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 if (trigger & IRQ_TYPE_EDGE_FALLING) |
| 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", |
| .irq_enable = pl061_irq_enable, |
| .irq_disable = pl061_irq_disable, |
| .irq_set_type = pl061_irq_type, |
| }; |
| |
| static void pl061_irq_handler(unsigned irq, struct irq_desc *desc) |
| { |
| struct list_head *chip_list = get_irq_data(irq); |
| struct list_head *ptr; |
| struct pl061_gpio *chip; |
| |
| desc->irq_data.chip->irq_ack(&desc->irq_data); |
| 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_set_bit(offset, &pending, PL061_GPIO_NR) |
| generic_handle_irq(pl061_to_irq(&chip->gc, offset)); |
| } |
| desc->irq_data.chip->irq_unmask(&desc->irq_data); |
| } |
| |
| static int pl061_probe(struct amba_device *dev, const 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_data(irq, chip_list); |
| } else |
| chip_list = get_irq_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[] = { |
| { |
| .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"); |