mfd: Add irq support in 88pm860x

88PM860x is a complex PMIC device. It contains touch, charger, sound, rtc,
backlight, led, and so on.

Host communicates to 88PM860x by I2C bus. Use thread irq to support this
usage case.

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 219 insertions, 7 deletions

diff --git a/drivers/mfd/88pm860x-core.c b/drivers/mfd/88pm860x-core.c
index 72b00304dc3..9185f0d945f 100644
--- a/drivers/mfd/88pm860x-core.c
+++ b/drivers/mfd/88pm860x-core.c
@@ -11,6 +11,7 @@
 
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/i2c.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/mfd/core.h>
@@ -67,15 +68,209 @@ static struct mfd_cell pm8607_devs[] = {
         PM8607_REG_DEVS(ldo14, LDO14),
 };
 
-static void device_8606_init(struct pm860x_chip *chip, struct i2c_client *i2c,
-                             struct pm860x_platform_data *pdata)
+#define CHECK_IRQ(irq)                                  \
+do {                                                    \
+        if ((irq < 0) || (irq >= PM860X_NUM_IRQ))       \
+                return -EINVAL;                         \
+} while (0)
+
+/* IRQs only occur on 88PM8607 */
+int pm860x_mask_irq(struct pm860x_chip *chip, int irq)
+{
+        struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
+                                : chip->companion;
+        int offset, data, ret;
+
+        CHECK_IRQ(irq);
+
+        offset = (irq >> 3) + PM8607_INT_MASK_1;
+        data = 1 << (irq % 8);
+        ret = pm860x_set_bits(i2c, offset, data, 0);
+
+        return ret;
+}
+EXPORT_SYMBOL(pm860x_mask_irq);
+
+int pm860x_unmask_irq(struct pm860x_chip *chip, int irq)
+{
+        struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
+                                : chip->companion;
+        int offset, data, ret;
+
+        CHECK_IRQ(irq);
+
+        offset = (irq >> 3) + PM8607_INT_MASK_1;
+        data = 1 << (irq % 8);
+        ret = pm860x_set_bits(i2c, offset, data, data);
+
+        return ret;
+}
+EXPORT_SYMBOL(pm860x_unmask_irq);
+
+#define INT_STATUS_NUM          (3)
+
+static irqreturn_t pm8607_irq_thread(int irq, void *data)
+{
+        DECLARE_BITMAP(irq_status, PM860X_NUM_IRQ);
+        struct pm860x_chip *chip = data;
+        struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
+                                : chip->companion;
+        unsigned char status_buf[INT_STATUS_NUM << 1];
+        unsigned long value;
+        int i, ret;
+
+        irq_status[0] = 0;
+
+        /* read out status register */
+        ret = pm860x_bulk_read(i2c, PM8607_INT_STATUS1,
+                                INT_STATUS_NUM << 1, status_buf);
+        if (ret < 0)
+                goto out;
+        if (chip->irq_mode) {
+                /* 0, clear by read. 1, clear by write */
+                ret = pm860x_bulk_write(i2c, PM8607_INT_STATUS1,
+                                        INT_STATUS_NUM, status_buf);
+                if (ret < 0)
+                        goto out;
+        }
+
+        /* clear masked interrupt status */
+        for (i = 0, value = 0; i < INT_STATUS_NUM; i++) {
+                status_buf[i] &= status_buf[i + INT_STATUS_NUM];
+                irq_status[0] |= status_buf[i] << (i * 8);
+        }
+
+        while (!bitmap_empty(irq_status, PM860X_NUM_IRQ)) {
+                irq = find_first_bit(irq_status, PM860X_NUM_IRQ);
+                clear_bit(irq, irq_status);
+                dev_dbg(chip->dev, "Servicing IRQ #%d\n", irq);
+
+                mutex_lock(&chip->irq_lock);
+                if (chip->irq[irq].handler)
+                        chip->irq[irq].handler(irq, chip->irq[irq].data);
+                else {
+                        pm860x_mask_irq(chip, irq);
+                        dev_err(chip->dev, "Nobody cares IRQ %d. "
+                                "Now mask it.\n", irq);
+                        for (i = 0; i < (INT_STATUS_NUM << 1); i++) {
+                                dev_err(chip->dev, "status[%d]:%x\n", i,
+                                        status_buf[i]);
+                        }
+                }
+                mutex_unlock(&chip->irq_lock);
+        }
+out:
+        return IRQ_HANDLED;
+}
+
+int pm860x_request_irq(struct pm860x_chip *chip, int irq,
+                       irq_handler_t handler, void *data)
 {
+        CHECK_IRQ(irq);
+        if (!handler)
+                return -EINVAL;
+
+        mutex_lock(&chip->irq_lock);
+        chip->irq[irq].handler = handler;
+        chip->irq[irq].data = data;
+        mutex_unlock(&chip->irq_lock);
+
+        return 0;
 }
+EXPORT_SYMBOL(pm860x_request_irq);
 
-static void device_8607_init(struct pm860x_chip *chip, struct i2c_client *i2c,
-                             struct pm860x_platform_data *pdata)
+int pm860x_free_irq(struct pm860x_chip *chip, int irq)
 {
-        int i, count;
+        CHECK_IRQ(irq);
+
+        mutex_lock(&chip->irq_lock);
+        chip->irq[irq].handler = NULL;
+        chip->irq[irq].data = NULL;
+        mutex_unlock(&chip->irq_lock);
+
+        return 0;
+}
+EXPORT_SYMBOL(pm860x_free_irq);
+
+static int __devinit device_irq_init(struct pm860x_chip *chip,
+                                     struct pm860x_platform_data *pdata)
+{
+        struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
+                                : chip->companion;
+        unsigned char status_buf[INT_STATUS_NUM];
+        int data, mask, ret = -EINVAL;
+
+        mutex_init(&chip->irq_lock);
+
+        mask = PM8607_B0_MISC1_INV_INT | PM8607_B0_MISC1_INT_CLEAR
+                | PM8607_B0_MISC1_INT_MASK;
+        data = 0;
+        chip->irq_mode = 0;
+        if (pdata && pdata->irq_mode) {
+                /*
+                 * irq_mode defines the way of clearing interrupt. If it's 1,
+                 * clear IRQ by write. Otherwise, clear it by read.
+                 * This control bit is valid from 88PM8607 B0 steping.
+                 */
+                data |= PM8607_B0_MISC1_INT_CLEAR;
+                chip->irq_mode = 1;
+        }
+        ret = pm860x_set_bits(i2c, PM8607_B0_MISC1, mask, data);
+        if (ret < 0)
+                goto out;
+
+        /* mask all IRQs */
+        memset(status_buf, 0, INT_STATUS_NUM);
+        ret = pm860x_bulk_write(i2c, PM8607_INT_MASK_1,
+                                INT_STATUS_NUM, status_buf);
+        if (ret < 0)
+                goto out;
+
+        if (chip->irq_mode) {
+                /* clear interrupt status by write */
+                memset(status_buf, 0xFF, INT_STATUS_NUM);
+                ret = pm860x_bulk_write(i2c, PM8607_INT_STATUS1,
+                                        INT_STATUS_NUM, status_buf);
+        } else {
+                /* clear interrupt status by read */
+                ret = pm860x_bulk_read(i2c, PM8607_INT_STATUS1,
+                                        INT_STATUS_NUM, status_buf);
+        }
+        if (ret < 0)
+                goto out;
+
+        memset(chip->irq, 0, sizeof(struct pm860x_irq) * PM860X_NUM_IRQ);
+
+        ret = request_threaded_irq(i2c->irq, NULL, pm8607_irq_thread,
+                                IRQF_ONESHOT | IRQF_TRIGGER_LOW,
+                                "88PM8607", chip);
+        if (ret < 0) {
+                dev_err(chip->dev, "Failed to request IRQ #%d.\n", i2c->irq);
+                goto out;
+        }
+        chip->chip_irq = i2c->irq;
+        return 0;
+out:
+        return ret;
+}
+
+static void __devexit device_irq_exit(struct pm860x_chip *chip)
+{
+        if (chip->chip_irq >= 0)
+                free_irq(chip->chip_irq, chip);
+}
+
+static void __devinit device_8606_init(struct pm860x_chip *chip,
+                                       struct i2c_client *i2c,
+                                       struct pm860x_platform_data *pdata)
+{
+}
+
+static void __devinit device_8607_init(struct pm860x_chip *chip,
+                                       struct i2c_client *i2c,
+                                       struct pm860x_platform_data *pdata)
+{
+        int i, count, data;
         int ret;
 
         ret = pm860x_reg_read(i2c, PM8607_CHIP_ID);
@@ -91,7 +286,6 @@ static void device_8607_init(struct pm860x_chip *chip, struct i2c_client *i2c,
                         "Chip ID: %02x\n", ret);
                 goto out;
         }
-        chip->chip_version = ret;
 
         ret = pm860x_reg_read(i2c, PM8607_BUCK3);
         if (ret < 0) {
@@ -101,12 +295,26 @@ static void device_8607_init(struct pm860x_chip *chip, struct i2c_client *i2c,
         if (ret & PM8607_BUCK3_DOUBLE)
                 chip->buck3_double = 1;
 
-        ret = pm860x_reg_read(i2c, PM8607_MISC1);
+        ret = pm860x_reg_read(i2c, PM8607_B0_MISC1);
         if (ret < 0) {
                 dev_err(chip->dev, "Failed to read MISC1 register: %d\n", ret);
                 goto out;
         }
 
+        if (pdata && (pdata->i2c_port == PI2C_PORT))
+                data = PM8607_B0_MISC1_PI2C;
+        else
+                data = 0;
+        ret = pm860x_set_bits(i2c, PM8607_B0_MISC1, PM8607_B0_MISC1_PI2C, data);
+        if (ret < 0) {
+                dev_err(chip->dev, "Failed to access MISC1:%d\n", ret);
+                goto out;
+        }
+
+        ret = device_irq_init(chip, pdata);
+        if (ret < 0)
+                goto out;
+
         count = ARRAY_SIZE(pm8607_devs);
         for (i = 0; i < count; i++) {
                 ret = mfd_add_devices(chip->dev, i, &pm8607_devs[i],
@@ -123,6 +331,8 @@ out:
 int pm860x_device_init(struct pm860x_chip *chip,
                        struct pm860x_platform_data *pdata)
 {
+        chip->chip_irq = -EINVAL;
+
         switch (chip->id) {
         case CHIP_PM8606:
                 device_8606_init(chip, chip->client, pdata);
@@ -142,11 +352,13 @@ int pm860x_device_init(struct pm860x_chip *chip,
                         break;
                 }
         }
+
         return 0;
 }
 
 void pm860x_device_exit(struct pm860x_chip *chip)
 {
+        device_irq_exit(chip);
         mfd_remove_devices(chip->dev);
 }