kernel-ark/drivers/gpio/gpio-langwell.c
David Cohen 2519f9abce gpio-langwell: fix irq conflicts when DT is not used
When DT is not used IOAPIC does not register irq domain. As result
IOAPIC won't care about gpio-langwell's virq and may cause conflict if
an irq number is equal to gpio-langwell's virq mapped beforehand.

This patch tells gpio_langwell to not ignore irq_base if != 0 and
preferably use it to avoid the conflict.

If DT is used, irq_base can safely be 0.

Signed-off-by: David Cohen <david.a.cohen@intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-05-20 20:10:22 +02:00

510 lines
12 KiB
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.
* Whitney point.
*/
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/platform_device.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>
#include <linux/pm_runtime.h>
#include <linux/irqdomain.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 */
GAFR, /* alt function */
};
struct lnw_gpio {
struct gpio_chip chip;
void *reg_base;
spinlock_t lock;
struct pci_dev *pdev;
struct irq_domain *domain;
};
#define to_lnw_priv(chip) container_of(chip, struct lnw_gpio, chip)
static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned offset,
enum GPIO_REG reg_type)
{
struct lnw_gpio *lnw = to_lnw_priv(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 void __iomem *gpio_reg_2bit(struct gpio_chip *chip, unsigned offset,
enum GPIO_REG reg_type)
{
struct lnw_gpio *lnw = to_lnw_priv(chip);
unsigned nreg = chip->ngpio / 32;
u8 reg = offset / 16;
void __iomem *ptr;
ptr = (void __iomem *)(lnw->reg_base + reg_type * nreg * 4 + reg * 4);
return ptr;
}
static int lnw_gpio_request(struct gpio_chip *chip, unsigned offset)
{
void __iomem *gafr = gpio_reg_2bit(chip, offset, GAFR);
u32 value = readl(gafr);
int shift = (offset % 16) << 1, af = (value >> shift) & 3;
if (af) {
value &= ~(3 << shift);
writel(value, gafr);
}
return 0;
}
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 = to_lnw_priv(chip);
void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
u32 value;
unsigned long flags;
if (lnw->pdev)
pm_runtime_get(&lnw->pdev->dev);
spin_lock_irqsave(&lnw->lock, flags);
value = readl(gpdr);
value &= ~BIT(offset % 32);
writel(value, gpdr);
spin_unlock_irqrestore(&lnw->lock, flags);
if (lnw->pdev)
pm_runtime_put(&lnw->pdev->dev);
return 0;
}
static int lnw_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int value)
{
struct lnw_gpio *lnw = to_lnw_priv(chip);
void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
unsigned long flags;
lnw_gpio_set(chip, offset, value);
if (lnw->pdev)
pm_runtime_get(&lnw->pdev->dev);
spin_lock_irqsave(&lnw->lock, flags);
value = readl(gpdr);
value |= BIT(offset % 32);
writel(value, gpdr);
spin_unlock_irqrestore(&lnw->lock, flags);
if (lnw->pdev)
pm_runtime_put(&lnw->pdev->dev);
return 0;
}
static int lnw_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
struct lnw_gpio *lnw = to_lnw_priv(chip);
return irq_create_mapping(lnw->domain, offset);
}
static int lnw_irq_type(struct irq_data *d, unsigned type)
{
struct lnw_gpio *lnw = irq_data_get_irq_chip_data(d);
u32 gpio = irqd_to_hwirq(d);
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;
if (lnw->pdev)
pm_runtime_get(&lnw->pdev->dev);
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);
if (lnw->pdev)
pm_runtime_put(&lnw->pdev->dev);
return 0;
}
static void lnw_irq_unmask(struct irq_data *d)
{
}
static void lnw_irq_mask(struct irq_data *d)
{
}
static struct irq_chip lnw_irqchip = {
.name = "LNW-GPIO",
.irq_mask = lnw_irq_mask,
.irq_unmask = lnw_irq_unmask,
.irq_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 },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08eb), .driver_data = 96 },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08f7), .driver_data = 96 },
{ 0, }
};
MODULE_DEVICE_TABLE(pci, lnw_gpio_ids);
static void lnw_irq_handler(unsigned irq, struct irq_desc *desc)
{
struct irq_data *data = irq_desc_get_irq_data(desc);
struct lnw_gpio *lnw = irq_data_get_irq_handler_data(data);
struct irq_chip *chip = irq_data_get_irq_chip(data);
u32 base, gpio, mask;
unsigned long pending;
void __iomem *gedr;
/* 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);
while ((pending = readl(gedr))) {
gpio = __ffs(pending);
mask = BIT(gpio);
/* Clear before handling so we can't lose an edge */
writel(mask, gedr);
generic_handle_irq(irq_find_mapping(lnw->domain,
base + gpio));
}
}
chip->irq_eoi(data);
}
static void lnw_irq_init_hw(struct lnw_gpio *lnw)
{
void __iomem *reg;
unsigned base;
for (base = 0; base < lnw->chip.ngpio; base += 32) {
/* Clear the rising-edge detect register */
reg = gpio_reg(&lnw->chip, base, GRER);
writel(0, reg);
/* Clear the falling-edge detect register */
reg = gpio_reg(&lnw->chip, base, GFER);
writel(0, reg);
/* Clear the edge detect status register */
reg = gpio_reg(&lnw->chip, base, GEDR);
writel(~0, reg);
}
}
static int lnw_gpio_irq_map(struct irq_domain *d, unsigned int virq,
irq_hw_number_t hw)
{
struct lnw_gpio *lnw = d->host_data;
irq_set_chip_and_handler_name(virq, &lnw_irqchip, handle_simple_irq,
"demux");
irq_set_chip_data(virq, lnw);
irq_set_irq_type(virq, IRQ_TYPE_NONE);
return 0;
}
static const struct irq_domain_ops lnw_gpio_irq_ops = {
.map = lnw_gpio_irq_map,
.xlate = irq_domain_xlate_twocell,
};
static int lnw_gpio_runtime_idle(struct device *dev)
{
int err = pm_schedule_suspend(dev, 500);
if (!err)
return 0;
return -EBUSY;
}
static const struct dev_pm_ops lnw_gpio_pm_ops = {
SET_RUNTIME_PM_OPS(NULL, NULL, lnw_gpio_runtime_idle)
};
static int lnw_gpio_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
void *base;
resource_size_t start, len;
struct lnw_gpio *lnw;
u32 gpio_base;
u32 irq_base;
int retval;
int ngpio = id->driver_data;
retval = pci_enable_device(pdev);
if (retval)
return retval;
retval = pci_request_regions(pdev, "langwell_gpio");
if (retval) {
dev_err(&pdev->dev, "error requesting resources\n");
goto err_pci_req_region;
}
/* get the gpio_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");
retval = -EFAULT;
goto err_ioremap;
}
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 = devm_ioremap_nocache(&pdev->dev, start, len);
if (!base) {
dev_err(&pdev->dev, "error mapping bar0\n");
retval = -EFAULT;
goto err_ioremap;
}
lnw = devm_kzalloc(&pdev->dev, sizeof(*lnw), GFP_KERNEL);
if (!lnw) {
dev_err(&pdev->dev, "can't allocate langwell_gpio chip data\n");
retval = -ENOMEM;
goto err_ioremap;
}
lnw->reg_base = base;
lnw->chip.label = dev_name(&pdev->dev);
lnw->chip.request = lnw_gpio_request;
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 = ngpio;
lnw->chip.can_sleep = 0;
lnw->pdev = pdev;
lnw->domain = irq_domain_add_simple(pdev->dev.of_node, ngpio, irq_base,
&lnw_gpio_irq_ops, lnw);
if (!lnw->domain) {
retval = -ENOMEM;
goto err_ioremap;
}
pci_set_drvdata(pdev, lnw);
retval = gpiochip_add(&lnw->chip);
if (retval) {
dev_err(&pdev->dev, "langwell gpiochip_add error %d\n", retval);
goto err_ioremap;
}
lnw_irq_init_hw(lnw);
irq_set_handler_data(pdev->irq, lnw);
irq_set_chained_handler(pdev->irq, lnw_irq_handler);
spin_lock_init(&lnw->lock);
pm_runtime_put_noidle(&pdev->dev);
pm_runtime_allow(&pdev->dev);
return 0;
err_ioremap:
pci_release_regions(pdev);
err_pci_req_region:
pci_disable_device(pdev);
return retval;
}
static struct pci_driver lnw_gpio_driver = {
.name = "langwell_gpio",
.id_table = lnw_gpio_ids,
.probe = lnw_gpio_probe,
.driver = {
.pm = &lnw_gpio_pm_ops,
},
};
static int wp_gpio_probe(struct platform_device *pdev)
{
struct lnw_gpio *lnw;
struct gpio_chip *gc;
struct resource *rc;
int retval = 0;
rc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!rc)
return -EINVAL;
lnw = kzalloc(sizeof(struct lnw_gpio), GFP_KERNEL);
if (!lnw) {
dev_err(&pdev->dev,
"can't allocate whitneypoint_gpio chip data\n");
return -ENOMEM;
}
lnw->reg_base = ioremap_nocache(rc->start, resource_size(rc));
if (lnw->reg_base == NULL) {
retval = -EINVAL;
goto err_kmalloc;
}
spin_lock_init(&lnw->lock);
gc = &lnw->chip;
gc->label = dev_name(&pdev->dev);
gc->owner = THIS_MODULE;
gc->direction_input = lnw_gpio_direction_input;
gc->direction_output = lnw_gpio_direction_output;
gc->get = lnw_gpio_get;
gc->set = lnw_gpio_set;
gc->to_irq = NULL;
gc->base = 0;
gc->ngpio = 64;
gc->can_sleep = 0;
retval = gpiochip_add(gc);
if (retval) {
dev_err(&pdev->dev, "whitneypoint gpiochip_add error %d\n",
retval);
goto err_ioremap;
}
platform_set_drvdata(pdev, lnw);
return 0;
err_ioremap:
iounmap(lnw->reg_base);
err_kmalloc:
kfree(lnw);
return retval;
}
static int wp_gpio_remove(struct platform_device *pdev)
{
struct lnw_gpio *lnw = platform_get_drvdata(pdev);
int err;
err = gpiochip_remove(&lnw->chip);
if (err)
dev_err(&pdev->dev, "failed to remove gpio_chip.\n");
iounmap(lnw->reg_base);
kfree(lnw);
platform_set_drvdata(pdev, NULL);
return 0;
}
static struct platform_driver wp_gpio_driver = {
.probe = wp_gpio_probe,
.remove = wp_gpio_remove,
.driver = {
.name = "wp_gpio",
.owner = THIS_MODULE,
},
};
static int __init lnw_gpio_init(void)
{
int ret;
ret = pci_register_driver(&lnw_gpio_driver);
if (ret < 0)
return ret;
ret = platform_driver_register(&wp_gpio_driver);
if (ret < 0)
pci_unregister_driver(&lnw_gpio_driver);
return ret;
}
device_initcall(lnw_gpio_init);