--- /dev/null
+/*
+ * 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)));
+}
+
+/*
+ * 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 gpio;
+
+ 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(gpio, &pending, PL061_GPIO_NR)
+ generic_handle_irq(gpio_to_irq(gpio));
+ }
+ 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 unsigned long init_irq[BITS_TO_LONGS(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.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) {
+ 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");
projects / GitHub / MotorolaMobilityLLC / kernel-slsi.git / commitdiff