linux/drivers/gpio/pl061.c

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/*
* 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 cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#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(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 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",
.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_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_set_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_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[] __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");