linux/drivers/gpio/langwell_gpio.c
Alek Du 8081c84c9c gpio: add Penwell gpio support
Intel Penwell chip has two 96 pins GPIO blocks, which are very similiar as
Intel Langwell chip GPIO block, except for pin number difference. This
patch expends the original Langwell GPIO driver to support Penwell's.

Signed-off-by: Alek Du <alek.du@intel.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:42 -07:00

309 lines
8.0 KiB
C

/* langwell_gpio.c Moorestown platform Langwell chip GPIO driver
* Copyright (c) 2008 - 2009, Intel Corporation.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/* Supports:
* Moorestown platform Langwell chip.
* Medfield platform Penwell chip.
*/
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/stddef.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <linux/slab.h>
/*
* Langwell chip has 64 pins and thus there are 2 32bit registers to control
* each feature, while Penwell chip has 96 pins for each block, and need 3 32bit
* registers to control them, so we only define the order here instead of a
* structure, to get a bit offset for a pin (use GPDR as an example):
*
* nreg = ngpio / 32;
* reg = offset / 32;
* bit = offset % 32;
* reg_addr = reg_base + GPDR * nreg * 4 + reg * 4;
*
* so the bit of reg_addr is to control pin offset's GPDR feature
*/
enum GPIO_REG {
GPLR = 0, /* pin level read-only */
GPDR, /* pin direction */
GPSR, /* pin set */
GPCR, /* pin clear */
GRER, /* rising edge detect */
GFER, /* falling edge detect */
GEDR, /* edge detect result */
};
struct lnw_gpio {
struct gpio_chip chip;
void *reg_base;
spinlock_t lock;
unsigned irq_base;
};
static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned offset,
enum GPIO_REG reg_type)
{
struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
unsigned nreg = chip->ngpio / 32;
u8 reg = offset / 32;
void __iomem *ptr;
ptr = (void __iomem *)(lnw->reg_base + reg_type * nreg * 4 + reg * 4);
return ptr;
}
static int lnw_gpio_get(struct gpio_chip *chip, unsigned offset)
{
void __iomem *gplr = gpio_reg(chip, offset, GPLR);
return readl(gplr) & BIT(offset % 32);
}
static void lnw_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
void __iomem *gpsr, *gpcr;
if (value) {
gpsr = gpio_reg(chip, offset, GPSR);
writel(BIT(offset % 32), gpsr);
} else {
gpcr = gpio_reg(chip, offset, GPCR);
writel(BIT(offset % 32), gpcr);
}
}
static int lnw_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
u32 value;
unsigned long flags;
spin_lock_irqsave(&lnw->lock, flags);
value = readl(gpdr);
value &= ~BIT(offset % 32);
writel(value, gpdr);
spin_unlock_irqrestore(&lnw->lock, flags);
return 0;
}
static int lnw_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int value)
{
struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
unsigned long flags;
lnw_gpio_set(chip, offset, value);
spin_lock_irqsave(&lnw->lock, flags);
value = readl(gpdr);
value |= BIT(offset % 32);;
writel(value, gpdr);
spin_unlock_irqrestore(&lnw->lock, flags);
return 0;
}
static int lnw_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
return lnw->irq_base + offset;
}
static int lnw_irq_type(unsigned irq, unsigned type)
{
struct lnw_gpio *lnw = get_irq_chip_data(irq);
u32 gpio = irq - lnw->irq_base;
unsigned long flags;
u32 value;
void __iomem *grer = gpio_reg(&lnw->chip, gpio, GRER);
void __iomem *gfer = gpio_reg(&lnw->chip, gpio, GFER);
if (gpio >= lnw->chip.ngpio)
return -EINVAL;
spin_lock_irqsave(&lnw->lock, flags);
if (type & IRQ_TYPE_EDGE_RISING)
value = readl(grer) | BIT(gpio % 32);
else
value = readl(grer) & (~BIT(gpio % 32));
writel(value, grer);
if (type & IRQ_TYPE_EDGE_FALLING)
value = readl(gfer) | BIT(gpio % 32);
else
value = readl(gfer) & (~BIT(gpio % 32));
writel(value, gfer);
spin_unlock_irqrestore(&lnw->lock, flags);
return 0;
};
static void lnw_irq_unmask(unsigned irq)
{
};
static void lnw_irq_mask(unsigned irq)
{
};
static struct irq_chip lnw_irqchip = {
.name = "LNW-GPIO",
.mask = lnw_irq_mask,
.unmask = lnw_irq_unmask,
.set_type = lnw_irq_type,
};
static DEFINE_PCI_DEVICE_TABLE(lnw_gpio_ids) = { /* pin number */
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f), .driver_data = 64 },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081f), .driver_data = 96 },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081a), .driver_data = 96 },
{ 0, }
};
MODULE_DEVICE_TABLE(pci, lnw_gpio_ids);
static void lnw_irq_handler(unsigned irq, struct irq_desc *desc)
{
struct lnw_gpio *lnw = (struct lnw_gpio *)get_irq_data(irq);
u32 base, gpio;
void __iomem *gedr;
u32 gedr_v;
/* check GPIO controller to check which pin triggered the interrupt */
for (base = 0; base < lnw->chip.ngpio; base += 32) {
gedr = gpio_reg(&lnw->chip, base, GEDR);
gedr_v = readl(gedr);
if (!gedr_v)
continue;
for (gpio = base; gpio < base + 32; gpio++)
if (gedr_v & BIT(gpio % 32)) {
pr_debug("pin %d triggered\n", gpio);
generic_handle_irq(lnw->irq_base + gpio);
}
/* clear the edge detect status bit */
writel(gedr_v, gedr);
}
desc->chip->eoi(irq);
}
static int __devinit lnw_gpio_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
void *base;
int i;
resource_size_t start, len;
struct lnw_gpio *lnw;
u32 irq_base;
u32 gpio_base;
int retval = 0;
retval = pci_enable_device(pdev);
if (retval)
goto done;
retval = pci_request_regions(pdev, "langwell_gpio");
if (retval) {
dev_err(&pdev->dev, "error requesting resources\n");
goto err2;
}
/* get the irq_base from bar1 */
start = pci_resource_start(pdev, 1);
len = pci_resource_len(pdev, 1);
base = ioremap_nocache(start, len);
if (!base) {
dev_err(&pdev->dev, "error mapping bar1\n");
goto err3;
}
irq_base = *(u32 *)base;
gpio_base = *((u32 *)base + 1);
/* release the IO mapping, since we already get the info from bar1 */
iounmap(base);
/* get the register base from bar0 */
start = pci_resource_start(pdev, 0);
len = pci_resource_len(pdev, 0);
base = ioremap_nocache(start, len);
if (!base) {
dev_err(&pdev->dev, "error mapping bar0\n");
retval = -EFAULT;
goto err3;
}
lnw = kzalloc(sizeof(struct lnw_gpio), GFP_KERNEL);
if (!lnw) {
dev_err(&pdev->dev, "can't allocate langwell_gpio chip data\n");
retval = -ENOMEM;
goto err4;
}
lnw->reg_base = base;
lnw->irq_base = irq_base;
lnw->chip.label = dev_name(&pdev->dev);
lnw->chip.direction_input = lnw_gpio_direction_input;
lnw->chip.direction_output = lnw_gpio_direction_output;
lnw->chip.get = lnw_gpio_get;
lnw->chip.set = lnw_gpio_set;
lnw->chip.to_irq = lnw_gpio_to_irq;
lnw->chip.base = gpio_base;
lnw->chip.ngpio = id->driver_data;
lnw->chip.can_sleep = 0;
pci_set_drvdata(pdev, lnw);
retval = gpiochip_add(&lnw->chip);
if (retval) {
dev_err(&pdev->dev, "langwell gpiochip_add error %d\n", retval);
goto err5;
}
set_irq_data(pdev->irq, lnw);
set_irq_chained_handler(pdev->irq, lnw_irq_handler);
for (i = 0; i < lnw->chip.ngpio; i++) {
set_irq_chip_and_handler_name(i + lnw->irq_base, &lnw_irqchip,
handle_simple_irq, "demux");
set_irq_chip_data(i + lnw->irq_base, lnw);
}
spin_lock_init(&lnw->lock);
goto done;
err5:
kfree(lnw);
err4:
iounmap(base);
err3:
pci_release_regions(pdev);
err2:
pci_disable_device(pdev);
done:
return retval;
}
static struct pci_driver lnw_gpio_driver = {
.name = "langwell_gpio",
.id_table = lnw_gpio_ids,
.probe = lnw_gpio_probe,
};
static int __init lnw_gpio_init(void)
{
return pci_register_driver(&lnw_gpio_driver);
}
device_initcall(lnw_gpio_init);