gpio: add Intel Moorestown Platform Langwell chip gpio driver
The Langwell chip is the IO hub for Intel Moorestown platform which has a
64-pin gpio block device inside. It is exposed as a dedicated PCI device.
We use it to control outside peripheral as well as to do IRQ demuxing.
The gpio block uses MSI to send level type interrupt to IOAPIC.
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>
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index ccca08e..9ad20ff 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -180,6 +180,12 @@
If unsure, say N.
+config GPIO_LANGWELL
+ bool "Intel Moorestown Platform Langwell GPIO support"
+ depends on PCI
+ help
+ Say Y here to support Intel Moorestown platform GPIO.
+
comment "SPI GPIO expanders:"
config GPIO_MAX7301
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index c1ac034..b8eef76 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -4,6 +4,7 @@
obj-$(CONFIG_GPIOLIB) += gpiolib.o
+obj-$(CONFIG_GPIO_LANGWELL) += langwell_gpio.o
obj-$(CONFIG_GPIO_MAX7301) += max7301.o
obj-$(CONFIG_GPIO_MAX732X) += max732x.o
obj-$(CONFIG_GPIO_MC33880) += mc33880.o
diff --git a/drivers/gpio/langwell_gpio.c b/drivers/gpio/langwell_gpio.c
new file mode 100644
index 0000000..5711ce5
--- /dev/null
+++ b/drivers/gpio/langwell_gpio.c
@@ -0,0 +1,297 @@
+/* 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.
+ */
+
+#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>
+
+struct lnw_gpio_register {
+ u32 GPLR[2];
+ u32 GPDR[2];
+ u32 GPSR[2];
+ u32 GPCR[2];
+ u32 GRER[2];
+ u32 GFER[2];
+ u32 GEDR[2];
+};
+
+struct lnw_gpio {
+ struct gpio_chip chip;
+ struct lnw_gpio_register *reg_base;
+ spinlock_t lock;
+ unsigned irq_base;
+};
+
+static int lnw_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
+ u8 reg = offset / 32;
+ void __iomem *gplr;
+
+ gplr = (void __iomem *)(&lnw->reg_base->GPLR[reg]);
+ return readl(gplr) & BIT(offset % 32);
+}
+
+static void lnw_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ struct lnw_gpio *lnw = container_of(chip, struct lnw_gpio, chip);
+ u8 reg = offset / 32;
+ void __iomem *gpsr, *gpcr;
+
+ if (value) {
+ gpsr = (void __iomem *)(&lnw->reg_base->GPSR[reg]);
+ writel(BIT(offset % 32), gpsr);
+ } else {
+ gpcr = (void __iomem *)(&lnw->reg_base->GPCR[reg]);
+ 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);
+ u8 reg = offset / 32;
+ u32 value;
+ unsigned long flags;
+ void __iomem *gpdr;
+
+ gpdr = (void __iomem *)(&lnw->reg_base->GPDR[reg]);
+ 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);
+ u8 reg = offset / 32;
+ unsigned long flags;
+ void __iomem *gpdr;
+
+ lnw_gpio_set(chip, offset, value);
+ gpdr = (void __iomem *)(&lnw->reg_base->GPDR[reg]);
+ 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;
+ u8 reg = gpio / 32;
+ unsigned long flags;
+ u32 value;
+ void __iomem *grer = (void __iomem *)(&lnw->reg_base->GRER[reg]);
+ void __iomem *gfer = (void __iomem *)(&lnw->reg_base->GFER[reg]);
+
+ if (gpio < 0 || 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)
+{
+ struct lnw_gpio *lnw = get_irq_chip_data(irq);
+ u32 gpio = irq - lnw->irq_base;
+ u8 reg = gpio / 32;
+ void __iomem *gedr;
+
+ gedr = (void __iomem *)(&lnw->reg_base->GEDR[reg]);
+ writel(BIT(gpio % 32), gedr);
+};
+
+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 struct pci_device_id lnw_gpio_ids[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f) },
+ { 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 reg, gpio;
+ void __iomem *gedr;
+ u32 gedr_v;
+
+ /* check GPIO controller to check which pin triggered the interrupt */
+ for (reg = 0; reg < lnw->chip.ngpio / 32; reg++) {
+ gedr = (void __iomem *)(&lnw->reg_base->GEDR[reg]);
+ gedr_v = readl(gedr);
+ if (!gedr_v)
+ continue;
+ for (gpio = reg*32; gpio < reg*32+32; gpio++) {
+ gedr_v = readl(gedr);
+ 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 = 64;
+ 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);