gpio-ml-ioh: Support interrupt function

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

2 files changed, 207 insertions, 3 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index d539efd96d4b..04499c19e986 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -402,6 +402,7 @@ config GPIO_PCH
 config GPIO_ML_IOH
         tristate "OKI SEMICONDUCTOR ML7213 IOH GPIO support"
         depends on PCI
+        select GENERIC_IRQ_CHIP
         help
           ML7213 is companion chip for Intel Atom E6xx series.
           This driver can be used for OKI SEMICONDUCTOR ML7213 IOH(Input/Output
diff --git a/drivers/gpio/gpio-ml-ioh.c b/drivers/gpio/gpio-ml-ioh.c
index 655e55c55e02..4fab37bf564d 100644
--- a/drivers/gpio/gpio-ml-ioh.c
+++ b/drivers/gpio/gpio-ml-ioh.c
@@ -18,6 +18,17 @@
 #include <linux/slab.h>
 #include <linux/pci.h>
 #include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+
+#define IOH_EDGE_FALLING        0
+#define IOH_EDGE_RISING         BIT(0)
+#define IOH_LEVEL_L             BIT(1)
+#define IOH_LEVEL_H             (BIT(0) | BIT(1))
+#define IOH_EDGE_BOTH           BIT(2)
+#define IOH_IM_MASK             (BIT(0) | BIT(1) | BIT(2))
+
+#define IOH_IRQ_BASE            0
 
 #define PCI_VENDOR_ID_ROHM             0x10DB
 
@@ -46,12 +57,20 @@ struct ioh_regs {
 
 /**
  * struct ioh_gpio_reg_data - The register store data.
+ * @ien_reg     To store contents of interrupt enable register.
+ * @imask_reg:  To store contents of interrupt mask regist
  * @po_reg:     To store contents of PO register.
  * @pm_reg:     To store contents of PM register.
+ * @im0_reg:    To store contents of interrupt mode regist0
+ * @im1_reg:    To store contents of interrupt mode regist1
  */
 struct ioh_gpio_reg_data {
+        u32 ien_reg;
+        u32 imask_reg;
         u32 po_reg;
         u32 pm_reg;
+        u32 im0_reg;
+        u32 im1_reg;
 };
 
 /**
@@ -63,6 +82,9 @@ struct ioh_gpio_reg_data {
  * @ioh_gpio_reg:               Memory mapped Register data is saved here
  *                              when suspend.
  * @ch:                         Indicate GPIO channel
+ * @irq_base:           Save base of IRQ number for interrupt
+ * @spinlock:           Used for register access protection in
+ *                              interrupt context ioh_irq_type and PM;
  */
 struct ioh_gpio {
         void __iomem *base;
@@ -72,6 +94,8 @@ struct ioh_gpio {
         struct ioh_gpio_reg_data ioh_gpio_reg;
         struct mutex lock;
         int ch;
+        int irq_base;
+        spinlock_t spinlock;
 };
 
 static const int num_ports[] = {6, 12, 16, 16, 15, 16, 16, 12};
@@ -147,6 +171,10 @@ static void ioh_gpio_save_reg_conf(struct ioh_gpio *chip)
 {
         chip->ioh_gpio_reg.po_reg = ioread32(&chip->reg->regs[chip->ch].po);
         chip->ioh_gpio_reg.pm_reg = ioread32(&chip->reg->regs[chip->ch].pm);
+        chip->ioh_gpio_reg.ien_reg = ioread32(&chip->reg->regs[chip->ch].ien);
+        chip->ioh_gpio_reg.imask_reg = ioread32(&chip->reg->regs[chip->ch].imask);
+        chip->ioh_gpio_reg.im0_reg = ioread32(&chip->reg->regs[chip->ch].im_0);
+        chip->ioh_gpio_reg.im1_reg = ioread32(&chip->reg->regs[chip->ch].im_1);
 }
 
 /*
@@ -154,13 +182,21 @@ static void ioh_gpio_save_reg_conf(struct ioh_gpio *chip)
  */
 static void ioh_gpio_restore_reg_conf(struct ioh_gpio *chip)
 {
-        /* to store contents of PO register */
         iowrite32(chip->ioh_gpio_reg.po_reg, &chip->reg->regs[chip->ch].po);
-        /* to store contents of PM register */
         iowrite32(chip->ioh_gpio_reg.pm_reg, &chip->reg->regs[chip->ch].pm);
+        iowrite32(chip->ioh_gpio_reg.ien_reg, &chip->reg->regs[chip->ch].ien);
+        iowrite32(chip->ioh_gpio_reg.imask_reg, &chip->reg->regs[chip->ch].imask);
+        iowrite32(chip->ioh_gpio_reg.im0_reg, &chip->reg->regs[chip->ch].im_0);
+        iowrite32(chip->ioh_gpio_reg.im1_reg, &chip->reg->regs[chip->ch].im_1);
 }
 #endif
 
+static int ioh_gpio_to_irq(struct gpio_chip *gpio, unsigned offset)
+{
+        struct ioh_gpio *chip = container_of(gpio, struct ioh_gpio, gpio);
+        return chip->irq_base + offset;
+}
+
 static void ioh_gpio_setup(struct ioh_gpio *chip, int num_port)
 {
         struct gpio_chip *gpio = &chip->gpio;
@@ -175,16 +211,148 @@ static void ioh_gpio_setup(struct ioh_gpio *chip, int num_port)
         gpio->base = -1;
         gpio->ngpio = num_port;
         gpio->can_sleep = 0;
+        gpio->to_irq = ioh_gpio_to_irq;
+}
+
+static int ioh_irq_type(struct irq_data *d, unsigned int type)
+{
+        u32 im;
+        u32 *im_reg;
+        u32 ien;
+        u32 im_pos;
+        int ch;
+        unsigned long flags;
+        u32 val;
+        int irq = d->irq;
+        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+        struct ioh_gpio *chip = gc->private;
+
+        ch = irq - chip->irq_base;
+        if (irq <= chip->irq_base + 7) {
+                im_reg = &chip->reg->regs[chip->ch].im_0;
+                im_pos = ch;
+        } else {
+                im_reg = &chip->reg->regs[chip->ch].im_1;
+                im_pos = ch - 8;
+        }
+        dev_dbg(chip->dev, "%s:irq=%d type=%d ch=%d pos=%d type=%d\n",
+                __func__, irq, type, ch, im_pos, type);
+
+        spin_lock_irqsave(&chip->spinlock, flags);
+
+        switch (type) {
+        case IRQ_TYPE_EDGE_RISING:
+                val = IOH_EDGE_RISING;
+                break;
+        case IRQ_TYPE_EDGE_FALLING:
+                val = IOH_EDGE_FALLING;
+                break;
+        case IRQ_TYPE_EDGE_BOTH:
+                val = IOH_EDGE_BOTH;
+                break;
+        case IRQ_TYPE_LEVEL_HIGH:
+                val = IOH_LEVEL_H;
+                break;
+        case IRQ_TYPE_LEVEL_LOW:
+                val = IOH_LEVEL_L;
+                break;
+        case IRQ_TYPE_PROBE:
+                goto end;
+        default:
+                dev_warn(chip->dev, "%s: unknown type(%dd)",
+                        __func__, type);
+                goto end;
+        }
+
+        /* Set interrupt mode */
+        im = ioread32(im_reg) & ~(IOH_IM_MASK << (im_pos * 4));
+        iowrite32(im | (val << (im_pos * 4)), im_reg);
+
+        /* iclr */
+        iowrite32(BIT(ch), &chip->reg->regs[chip->ch].iclr);
+
+        /* IMASKCLR */
+        iowrite32(BIT(ch), &chip->reg->regs[chip->ch].imaskclr);
+
+        /* Enable interrupt */
+        ien = ioread32(&chip->reg->regs[chip->ch].ien);
+        iowrite32(ien | BIT(ch), &chip->reg->regs[chip->ch].ien);
+end:
+        spin_unlock_irqrestore(&chip->spinlock, flags);
+
+        return 0;
+}
+
+static void ioh_irq_unmask(struct irq_data *d)
+{
+        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+        struct ioh_gpio *chip = gc->private;
+
+        iowrite32(1 << (d->irq - chip->irq_base),
+                  &chip->reg->regs[chip->ch].imaskclr);
+}
+
+static void ioh_irq_mask(struct irq_data *d)
+{
+        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+        struct ioh_gpio *chip = gc->private;
+
+        iowrite32(1 << (d->irq - chip->irq_base),
+                  &chip->reg->regs[chip->ch].imask);
+}
+
+static irqreturn_t ioh_gpio_handler(int irq, void *dev_id)
+{
+        struct ioh_gpio *chip = dev_id;
+        u32 reg_val;
+        int i, j;
+        int ret = IRQ_NONE;
+
+        for (i = 0; i < 8; i++) {
+                reg_val = ioread32(&chip->reg->regs[i].istatus);
+                for (j = 0; j < num_ports[i]; j++) {
+                        if (reg_val & BIT(j)) {
+                                dev_dbg(chip->dev,
+                                        "%s:[%d]:irq=%d status=0x%x\n",
+                                        __func__, j, irq, reg_val);
+                                iowrite32(BIT(j),
+                                          &chip->reg->regs[chip->ch].iclr);
+                                generic_handle_irq(chip->irq_base + j);
+                                ret = IRQ_HANDLED;
+                        }
+                }
+        }
+        return ret;
+}
+
+static __devinit void ioh_gpio_alloc_generic_chip(struct ioh_gpio *chip,
+                                unsigned int irq_start, unsigned int num)
+{
+        struct irq_chip_generic *gc;
+        struct irq_chip_type *ct;
+
+        gc = irq_alloc_generic_chip("ioh_gpio", 1, irq_start, chip->base,
+                                    handle_simple_irq);
+        gc->private = chip;
+        ct = gc->chip_types;
+
+        ct->chip.irq_mask = ioh_irq_mask;
+        ct->chip.irq_unmask = ioh_irq_unmask;
+        ct->chip.irq_set_type = ioh_irq_type;
+
+        irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
+                               IRQ_NOREQUEST | IRQ_NOPROBE, 0);
 }
 
 static int __devinit ioh_gpio_probe(struct pci_dev *pdev,
                                     const struct pci_device_id *id)
 {
         int ret;
-        int i;
+        int i, j;
         struct ioh_gpio *chip;
         void __iomem *base;
         void __iomem *chip_save;
+        int irq_base;
 
         ret = pci_enable_device(pdev);
         if (ret) {
@@ -228,10 +396,41 @@ static int __devinit ioh_gpio_probe(struct pci_dev *pdev,
         }
 
         chip = chip_save;
+        for (j = 0; j < 8; j++, chip++) {
+                irq_base = irq_alloc_descs(-1, IOH_IRQ_BASE, num_ports[j],
+                                           GFP_KERNEL);
+                if (irq_base < 0) {
+                        dev_warn(&pdev->dev,
+                                "ml_ioh_gpio: Failed to get IRQ base num\n");
+                        chip->irq_base = -1;
+                        goto err_irq_alloc_descs;
+                }
+                chip->irq_base = irq_base;
+                ioh_gpio_alloc_generic_chip(chip, irq_base, num_ports[j]);
+        }
+
+        chip = chip_save;
+        ret = request_irq(pdev->irq, ioh_gpio_handler,
+                             IRQF_SHARED, KBUILD_MODNAME, chip);
+        if (ret != 0) {
+                dev_err(&pdev->dev,
+                        "%s request_irq failed\n", __func__);
+                goto err_request_irq;
+        }
+
         pci_set_drvdata(pdev, chip);
 
         return 0;
 
+err_request_irq:
+        chip = chip_save;
+err_irq_alloc_descs:
+        while (--j >= 0) {
+                chip--;
+                irq_free_descs(chip->irq_base, num_ports[j]);
+        }
+
+        chip = chip_save;
 err_gpiochip_add:
         while (--i >= 0) {
                 chip--;
@@ -264,7 +463,11 @@ static void __devexit ioh_gpio_remove(struct pci_dev *pdev)
         void __iomem *chip_save;
 
         chip_save = chip;
+
+        free_irq(pdev->irq, chip);
+
         for (i = 0; i < 8; i++, chip++) {
+                irq_free_descs(chip->irq_base, num_ports[i]);
                 err = gpiochip_remove(&chip->gpio);
                 if (err)
                         dev_err(&pdev->dev, "Failed gpiochip_remove\n");