1 files changed, 358 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-pl061.c b/drivers/gpio/gpio-pl061.c
new file mode 100644
index 000000000000..2c5a18f32bf3
--- /dev/null
+++ b/drivers/gpio/gpio-pl061.c
@@ -0,0 +1,358 @@
+/*
+ * 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 = irq_get_handler_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;
+	}
+	irq_set_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);
+		irq_set_handler_data(irq, chip_list);
+	} else
+		chip_list = irq_get_handler_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);
+
+		irq_set_chip_and_handler(i + chip->irq_base, &pl061_irqchip,
+					 handle_simple_irq);
+		set_irq_flags(i+chip->irq_base, IRQF_VALID);
+		irq_set_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");