[PATCH] pch_gpio: support interrupt function

From: Tomoya MORINAGA
Date: Mon May 16 2011 - 22:41:07 EST


Support interrupt function.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@xxxxxxxxxxxxxxx>
---
drivers/gpio/Kconfig | 2 +-
drivers/gpio/pch_gpio.c | 153 +++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 154 insertions(+), 1 deletions(-)

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 664660e..bfb467b 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -326,7 +326,7 @@ config GPIO_LANGWELL
Say Y here to support Intel Langwell/Penwell GPIO.

config GPIO_PCH
- tristate "PCH GPIO of Intel Topcliff"
+ bool "PCH GPIO of Intel Topcliff"
depends on PCI
help
This driver is for PCH(Platform controller Hub) GPIO of Intel Topcliff
diff --git a/drivers/gpio/pch_gpio.c b/drivers/gpio/pch_gpio.c
index 2c6af87..939771a 100644
--- a/drivers/gpio/pch_gpio.c
+++ b/drivers/gpio/pch_gpio.c
@@ -17,10 +17,21 @@
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>

#define PCH_GPIO_ALL_PINS 0xfff /* Mask for GPIO pins 0 to 11 */
#define GPIO_NUM_PINS 12 /* Specifies number of GPIO PINS GPIO0-GPIO11 */

+#define PCH_EDGE_FALLING 0
+#define PCH_EDGE_RISING BIT(0)
+#define PCH_LEVEL_L BIT(1)
+#define PCH_LEVEL_H (BIT(0) | BIT(1))
+#define PCH_EDGE_BOTH BIT(2)
+#define PCH_IM_MASK (BIT(0) | BIT(1) | BIT(2))
+
+#define PCH_IRQ_BASE 23
+
struct pch_regs {
u32 ien;
u32 istatus;
@@ -55,6 +66,7 @@ struct pch_gpio_reg_data {
* @gpio: Data for GPIO infrastructure.
* @pch_gpio_reg: Memory mapped Register data is saved here
* when suspend.
+ * @lock: spin_lock variable
*/
struct pch_gpio {
void __iomem *base;
@@ -63,6 +75,8 @@ struct pch_gpio {
struct gpio_chip gpio;
struct pch_gpio_reg_data pch_gpio_reg;
struct mutex lock;
+ int irq_base;
+ spinlock_t spinlock;
};

static void pch_gpio_set(struct gpio_chip *gpio, unsigned nr, int val)
@@ -105,6 +119,7 @@ static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
reg_val |= (1 << nr);
else
reg_val &= ~(1 << nr);
+ iowrite32(reg_val, &chip->reg->po);

mutex_unlock(&chip->lock);

@@ -145,6 +160,12 @@ static void pch_gpio_restore_reg_conf(struct pch_gpio *chip)
iowrite32(chip->pch_gpio_reg.pm_reg, &chip->reg->pm);
}

+static int pch_gpio_to_irq(struct gpio_chip *gpio, unsigned offset)
+{
+ struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
+ return chip->irq_base + offset;
+}
+
static void pch_gpio_setup(struct pch_gpio *chip)
{
struct gpio_chip *gpio = &chip->gpio;
@@ -159,6 +180,101 @@ static void pch_gpio_setup(struct pch_gpio *chip)
gpio->base = -1;
gpio->ngpio = GPIO_NUM_PINS;
gpio->can_sleep = 0;
+ gpio->to_irq = pch_gpio_to_irq;
+}
+
+static int pch_irq_type(unsigned irq, unsigned type)
+{
+ u32 im;
+ u32 *im_reg;
+ u32 ien;
+ u32 im_pos;
+ int ch;
+ unsigned long flags;
+ u32 val;
+ struct pch_gpio *chip = get_irq_chip_data(irq);
+
+ ch = irq - chip->irq_base;
+ if (irq <= chip->irq_base + 7) {
+ im_reg = &chip->reg->im0;
+ im_pos = ch;
+ } else {
+ im_reg = &chip->reg->im1;
+ im_pos = ch - 8;
+ }
+ dev_dbg(chip->dev, "%s:irq=%d type=%d ch=%d pos=%d\n",
+ __func__, irq, type, ch, im_pos);
+
+ spin_lock_irqsave(&chip->spinlock, flags);
+
+ if (type == IRQ_TYPE_EDGE_RISING)
+ val = PCH_EDGE_RISING;
+ else if (type == IRQ_TYPE_EDGE_FALLING)
+ val = PCH_EDGE_FALLING;
+ else if (type == IRQ_TYPE_EDGE_BOTH)
+ val = PCH_EDGE_BOTH;
+ else if (type == IRQ_TYPE_LEVEL_HIGH)
+ val = PCH_LEVEL_L;
+ else if (type == IRQ_TYPE_LEVEL_LOW)
+ val = PCH_LEVEL_H;
+ else if (type == IRQ_TYPE_PROBE)
+ goto end;
+ else {
+ dev_warn(chip->dev, "%s: unknown type(%dd)", __func__, type);
+ goto end;
+ }
+
+ /* Set interrupt mode */
+ im = ioread32(im_reg) & ~(PCH_IM_MASK << (im_pos * 4));
+ iowrite32(im | (val << (im_pos * 4)), im_reg);
+
+ /* iclr */
+ iowrite32(BIT(ch), &chip->reg->iclr);
+
+ /* IMASKCLR */
+ iowrite32(BIT(ch), &chip->reg->imaskclr);
+
+ /* Enable interrupt */
+ ien = ioread32(&chip->reg->ien);
+ iowrite32(ien | BIT(ch), &chip->reg->ien);
+end:
+ spin_unlock_irqrestore(&chip->spinlock, flags);
+
+ return 0;
+}
+
+static void pch_irq_unmask(unsigned irq)
+{
+}
+
+static void pch_irq_mask(unsigned irq)
+{
+}
+
+static struct irq_chip pch_irqchip = {
+ .name = "PCH-GPIO",
+ .mask = pch_irq_mask,
+ .unmask = pch_irq_unmask,
+ .set_type = pch_irq_type,
+};
+
+static irqreturn_t pch_gpio_handler(int irq, void *dev_id)
+{
+ struct pch_gpio *chip = dev_id;
+ u32 reg_val = ioread32(&chip->reg->istatus);
+ int i;
+ int ret = IRQ_NONE;
+
+ for (i = 0; i < GPIO_NUM_PINS; i++) {
+ if (reg_val & BIT(i)) {
+ dev_dbg(chip->dev, "%s:[%d]:irq=%d status=0x%x\n",
+ __func__, i, irq, reg_val);
+ iowrite32(BIT(i), &chip->reg->iclr);
+ generic_handle_irq(chip->irq_base + i);
+ ret = IRQ_HANDLED;
+ }
+ }
+ return ret;
}

static int __devinit pch_gpio_probe(struct pci_dev *pdev,
@@ -166,6 +282,8 @@ static int __devinit pch_gpio_probe(struct pci_dev *pdev,
{
s32 ret;
struct pch_gpio *chip;
+ int irq_base;
+ int i;

chip = kzalloc(sizeof(*chip), GFP_KERNEL);
if (chip == NULL)
@@ -201,8 +319,41 @@ static int __devinit pch_gpio_probe(struct pci_dev *pdev,
goto err_gpiochip_add;
}

+ irq_base = irq_alloc_descs(-1, PCH_IRQ_BASE, GPIO_NUM_PINS, GFP_KERNEL);
+ if (irq_base < 0) {
+ dev_err(&pdev->dev, "PCH gpio: Failed to get IRQ base num\n");
+ goto err_irq_alloc_descs;
+ }
+
+ chip->irq_base = irq_base;
+
+ ret = request_irq(pdev->irq, pch_gpio_handler,
+ IRQF_SHARED, KBUILD_MODNAME, chip);
+ if (ret != 0) {
+ dev_err(&pdev->dev,
+ "%s request_irq failed\n", __func__);
+ goto err_request_irq;
+ }
+
+ for (i = 0; i < GPIO_NUM_PINS; i++) {
+ set_irq_chip_and_handler_name(i + irq_base, &pch_irqchip,
+ handle_simple_irq, "pch");
+ set_irq_chip_data(i + irq_base, chip);
+ }
+
+ /* Initialize interrupt ien register */
+ iowrite32(0, &chip->reg->ien);
+
return 0;

+err_request_irq:
+ irq_free_descs(irq_base, GPIO_NUM_PINS);
+
+err_irq_alloc_descs:
+ ret = gpiochip_remove(&chip->gpio);
+ if (ret)
+ dev_err(&pdev->dev, "%s gpiochip_remove failed\n", __func__);
+
err_gpiochip_add:
pci_iounmap(pdev, chip->base);

@@ -223,6 +374,8 @@ static void __devexit pch_gpio_remove(struct pci_dev *pdev)
int err;
struct pch_gpio *chip = pci_get_drvdata(pdev);

+ irq_free_descs(chip->irq_base, GPIO_NUM_PINS);
+
err = gpiochip_remove(&chip->gpio);
if (err)
dev_err(&pdev->dev, "Failed gpiochip_remove\n");
--
1.7.4

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