drivers/gpio/gpio-pl061.c - kernel/mindspeed - Git at Google

 /*
  * 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 == NO_IRQ)
 		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);

 	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
 	if (chip == NULL)
 		return -ENOMEM;

 	pdata = dev->dev.platform_data;
 	if (pdata) {
 		chip->gc.base = pdata->gpio_base;
 		chip->irq_base = pdata->irq_base;
 	} else if (dev->dev.of_node) {
 		chip->gc.base = -1;
 		chip->irq_base = NO_IRQ;
 	} else {
 		ret = -ENODEV;
 		goto free_mem;
 	}

 	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.ngpio = PL061_GPIO_NR;
 	chip->gc.label = dev_name(&dev->dev);
 	chip->gc.dev = &dev->dev;
 	chip->gc.owner = THIS_MODULE;

 	ret = gpiochip_add(&chip->gc);
 	if (ret)
 		goto iounmap;

 	/*
 	 * irq_chip support
 	 */

 	if (chip->irq_base == NO_IRQ)
 		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) {
 			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");
	/*
	* 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 == NO_IRQ)
	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);

	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
	if (chip == NULL)
	return -ENOMEM;

	pdata = dev->dev.platform_data;
	if (pdata) {
	chip->gc.base = pdata->gpio_base;
	chip->irq_base = pdata->irq_base;
	} else if (dev->dev.of_node) {
	chip->gc.base = -1;
	chip->irq_base = NO_IRQ;
	} else {
	ret = -ENODEV;
	goto free_mem;
	}

	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.ngpio = PL061_GPIO_NR;
	chip->gc.label = dev_name(&dev->dev);
	chip->gc.dev = &dev->dev;
	chip->gc.owner = THIS_MODULE;

	ret = gpiochip_add(&chip->gc);
	if (ret)
	goto iounmap;

	/*
	* irq_chip support
	*/

	if (chip->irq_base == NO_IRQ)
	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) {
	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");