#include <linux/kernel.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
+#include <linux/err.h>
 #include <linux/msm_ssbi.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/pm8xxx/pm8921.h>
 
 struct pm8921 {
        struct device                   *dev;
+       struct pm_irq_chip              *irq_chip;
 };
 
 static int pm8921_readb(const struct device *dev, u16 addr, u8 *val)
        return msm_ssbi_write(pmic->dev->parent, addr, buf, cnt);
 }
 
+static int pm8921_read_irq_stat(const struct device *dev, int irq)
+{
+       const struct pm8xxx_drvdata *pm8921_drvdata = dev_get_drvdata(dev);
+       const struct pm8921 *pmic = pm8921_drvdata->pm_chip_data;
+
+       return pm8xxx_get_irq_stat(pmic->irq_chip, irq);
+}
+
 static struct pm8xxx_drvdata pm8921_drvdata = {
        .pmic_readb             = pm8921_readb,
        .pmic_writeb            = pm8921_writeb,
        .pmic_read_buf          = pm8921_read_buf,
        .pmic_write_buf         = pm8921_write_buf,
+       .pmic_read_irq_stat     = pm8921_read_irq_stat,
 };
 
+static int __devinit pm8921_add_subdevices(const struct pm8921_platform_data
+                                          *pdata,
+                                          struct pm8921 *pmic,
+                                          u32 rev)
+{
+       int ret = 0, irq_base = 0;
+       struct pm_irq_chip *irq_chip;
+
+       if (pdata->irq_pdata) {
+               pdata->irq_pdata->irq_cdata.nirqs = PM8921_NR_IRQS;
+               pdata->irq_pdata->irq_cdata.rev = rev;
+               irq_base = pdata->irq_pdata->irq_base;
+               irq_chip = pm8xxx_irq_init(pmic->dev, pdata->irq_pdata);
+
+               if (IS_ERR(irq_chip)) {
+                       pr_err("Failed to init interrupts ret=%ld\n",
+                                       PTR_ERR(irq_chip));
+                       return PTR_ERR(irq_chip);
+               }
+               pmic->irq_chip = irq_chip;
+       }
+       return ret;
+}
+
 static int __devinit pm8921_probe(struct platform_device *pdev)
 {
        const struct pm8921_platform_data *pdata = pdev->dev.platform_data;
        struct pm8921 *pmic;
        int rc;
        u8 val;
+       u32 rev;
 
        if (!pdata) {
                pr_err("missing platform data\n");
                goto err_read_rev;
        }
        pr_info("PMIC revision 1: %02X\n", val);
+       rev = val;
 
        /* Read PMIC chip revision 2 */
        rc = msm_ssbi_read(pdev->dev.parent, REG_HWREV_2, &val, sizeof(val));
                goto err_read_rev;
        }
        pr_info("PMIC revision 2: %02X\n", val);
+       rev |= val << BITS_PER_BYTE;
 
        pmic->dev = &pdev->dev;
        pm8921_drvdata.pm_chip_data = pmic;
        platform_set_drvdata(pdev, &pm8921_drvdata);
 
+       rc = pm8921_add_subdevices(pdata, pmic, rev);
+       if (rc) {
+               pr_err("Cannot add subdevices rc=%d\n", rc);
+               goto err;
+       }
+
+       /* gpio might not work if no irq device is found */
+       WARN_ON(pmic->irq_chip == NULL);
+
        return 0;
 
+err:
+       mfd_remove_devices(pmic->dev);
+       platform_set_drvdata(pdev, NULL);
 err_read_rev:
        kfree(pmic);
        return rc;
                pmic = drvdata->pm_chip_data;
        if (pmic)
                mfd_remove_devices(pmic->dev);
+       if (pmic->irq_chip) {
+               pm8xxx_irq_exit(pmic->irq_chip);
+               pmic->irq_chip = NULL;
+       }
        platform_set_drvdata(pdev, NULL);
        kfree(pmic);
 
 
--- /dev/null
+/*
+ * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only 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.
+ */
+
+#define pr_fmt(fmt)    "%s: " fmt, __func__
+
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/mfd/pm8xxx/core.h>
+#include <linux/mfd/pm8xxx/irq.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+/* PMIC8xxx IRQ */
+
+#define        SSBI_REG_ADDR_IRQ_BASE          0x1BB
+
+#define        SSBI_REG_ADDR_IRQ_ROOT          (SSBI_REG_ADDR_IRQ_BASE + 0)
+#define        SSBI_REG_ADDR_IRQ_M_STATUS1     (SSBI_REG_ADDR_IRQ_BASE + 1)
+#define        SSBI_REG_ADDR_IRQ_M_STATUS2     (SSBI_REG_ADDR_IRQ_BASE + 2)
+#define        SSBI_REG_ADDR_IRQ_M_STATUS3     (SSBI_REG_ADDR_IRQ_BASE + 3)
+#define        SSBI_REG_ADDR_IRQ_M_STATUS4     (SSBI_REG_ADDR_IRQ_BASE + 4)
+#define        SSBI_REG_ADDR_IRQ_BLK_SEL       (SSBI_REG_ADDR_IRQ_BASE + 5)
+#define        SSBI_REG_ADDR_IRQ_IT_STATUS     (SSBI_REG_ADDR_IRQ_BASE + 6)
+#define        SSBI_REG_ADDR_IRQ_CONFIG        (SSBI_REG_ADDR_IRQ_BASE + 7)
+#define        SSBI_REG_ADDR_IRQ_RT_STATUS     (SSBI_REG_ADDR_IRQ_BASE + 8)
+
+#define        PM_IRQF_LVL_SEL                 0x01    /* level select */
+#define        PM_IRQF_MASK_FE                 0x02    /* mask falling edge */
+#define        PM_IRQF_MASK_RE                 0x04    /* mask rising edge */
+#define        PM_IRQF_CLR                     0x08    /* clear interrupt */
+#define        PM_IRQF_BITS_MASK               0x70
+#define        PM_IRQF_BITS_SHIFT              4
+#define        PM_IRQF_WRITE                   0x80
+
+#define        PM_IRQF_MASK_ALL                (PM_IRQF_MASK_FE | \
+                                       PM_IRQF_MASK_RE)
+
+struct pm_irq_chip {
+       struct device           *dev;
+       spinlock_t              pm_irq_lock;
+       unsigned int            devirq;
+       unsigned int            irq_base;
+       unsigned int            num_irqs;
+       unsigned int            num_blocks;
+       unsigned int            num_masters;
+       u8                      config[0];
+};
+
+static int pm8xxx_read_root_irq(const struct pm_irq_chip *chip, u8 *rp)
+{
+       return pm8xxx_readb(chip->dev, SSBI_REG_ADDR_IRQ_ROOT, rp);
+}
+
+static int pm8xxx_read_master_irq(const struct pm_irq_chip *chip, u8 m, u8 *bp)
+{
+       return pm8xxx_readb(chip->dev,
+                       SSBI_REG_ADDR_IRQ_M_STATUS1 + m, bp);
+}
+
+static int pm8xxx_read_block_irq(struct pm_irq_chip *chip, u8 bp, u8 *ip)
+{
+       int     rc;
+
+       spin_lock(&chip->pm_irq_lock);
+       rc = pm8xxx_writeb(chip->dev, SSBI_REG_ADDR_IRQ_BLK_SEL, bp);
+       if (rc) {
+               pr_err("Failed Selecting Block %d rc=%d\n", bp, rc);
+               goto bail;
+       }
+
+       rc = pm8xxx_readb(chip->dev, SSBI_REG_ADDR_IRQ_IT_STATUS, ip);
+       if (rc)
+               pr_err("Failed Reading Status rc=%d\n", rc);
+bail:
+       spin_unlock(&chip->pm_irq_lock);
+       return rc;
+}
+
+static int pm8xxx_config_irq(struct pm_irq_chip *chip, u8 bp, u8 cp)
+{
+       int     rc;
+
+       spin_lock(&chip->pm_irq_lock);
+       rc = pm8xxx_writeb(chip->dev, SSBI_REG_ADDR_IRQ_BLK_SEL, bp);
+       if (rc) {
+               pr_err("Failed Selecting Block %d rc=%d\n", bp, rc);
+               goto bail;
+       }
+
+       cp |= PM_IRQF_WRITE;
+       rc = pm8xxx_writeb(chip->dev, SSBI_REG_ADDR_IRQ_CONFIG, cp);
+       if (rc)
+               pr_err("Failed Configuring IRQ rc=%d\n", rc);
+bail:
+       spin_unlock(&chip->pm_irq_lock);
+       return rc;
+}
+
+static int pm8xxx_irq_block_handler(struct pm_irq_chip *chip, int block)
+{
+       int pmirq, irq, i, ret = 0;
+       u8 bits;
+
+       ret = pm8xxx_read_block_irq(chip, block, &bits);
+       if (ret) {
+               pr_err("Failed reading %d block ret=%d", block, ret);
+               return ret;
+       }
+       if (!bits) {
+               pr_err("block bit set in master but no irqs: %d", block);
+               return 0;
+       }
+
+       /* Check IRQ bits */
+       for (i = 0; i < 8; i++) {
+               if (bits & (1 << i)) {
+                       pmirq = block * 8 + i;
+                       irq = pmirq + chip->irq_base;
+                       generic_handle_irq(irq);
+               }
+       }
+       return 0;
+}
+
+static int pm8xxx_irq_master_handler(struct pm_irq_chip *chip, int master)
+{
+       u8 blockbits;
+       int block_number, i, ret = 0;
+
+       ret = pm8xxx_read_master_irq(chip, master, &blockbits);
+       if (ret) {
+               pr_err("Failed to read master %d ret=%d\n", master, ret);
+               return ret;
+       }
+       if (!blockbits) {
+               pr_err("master bit set in root but no blocks: %d", master);
+               return 0;
+       }
+
+       for (i = 0; i < 8; i++)
+               if (blockbits & (1 << i)) {
+                       block_number = master * 8 + i;  /* block # */
+                       ret |= pm8xxx_irq_block_handler(chip, block_number);
+               }
+       return ret;
+}
+
+static void pm8xxx_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+       struct pm_irq_chip *chip = irq_desc_get_handler_data(desc);
+       struct irq_chip *irq_chip = irq_desc_get_chip(desc);
+       u8      root;
+       int     i, ret, masters = 0;
+
+       ret = pm8xxx_read_root_irq(chip, &root);
+       if (ret) {
+               pr_err("Can't read root status ret=%d\n", ret);
+               return;
+       }
+
+       /* on pm8xxx series masters start from bit 1 of the root */
+       masters = root >> 1;
+
+       /* Read allowed masters for blocks. */
+       for (i = 0; i < chip->num_masters; i++)
+               if (masters & (1 << i))
+                       pm8xxx_irq_master_handler(chip, i);
+
+       irq_chip->irq_ack(&desc->irq_data);
+}
+
+static void pm8xxx_irq_mask_ack(struct irq_data *d)
+{
+       struct pm_irq_chip *chip = irq_data_get_irq_chip_data(d);
+       unsigned int pmirq = d->irq - chip->irq_base;
+       int     master, irq_bit;
+       u8      block, config;
+
+       block = pmirq / 8;
+       master = block / 8;
+       irq_bit = pmirq % 8;
+
+       config = chip->config[pmirq] | PM_IRQF_MASK_ALL | PM_IRQF_CLR;
+       pm8xxx_config_irq(chip, block, config);
+}
+
+static void pm8xxx_irq_unmask(struct irq_data *d)
+{
+       struct pm_irq_chip *chip = irq_data_get_irq_chip_data(d);
+       unsigned int pmirq = d->irq - chip->irq_base;
+       int     master, irq_bit;
+       u8      block, config;
+
+       block = pmirq / 8;
+       master = block / 8;
+       irq_bit = pmirq % 8;
+
+       config = chip->config[pmirq];
+       pm8xxx_config_irq(chip, block, config);
+}
+
+static int pm8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
+{
+       struct pm_irq_chip *chip = irq_data_get_irq_chip_data(d);
+       unsigned int pmirq = d->irq - chip->irq_base;
+       int master, irq_bit;
+       u8 block, config;
+
+       block = pmirq / 8;
+       master = block / 8;
+       irq_bit  = pmirq % 8;
+
+       chip->config[pmirq] = (irq_bit << PM_IRQF_BITS_SHIFT)
+                                                       | PM_IRQF_MASK_ALL;
+       if (flow_type & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)) {
+               if (flow_type & IRQF_TRIGGER_RISING)
+                       chip->config[pmirq] &= ~PM_IRQF_MASK_RE;
+               if (flow_type & IRQF_TRIGGER_FALLING)
+                       chip->config[pmirq] &= ~PM_IRQF_MASK_FE;
+       } else {
+               chip->config[pmirq] |= PM_IRQF_LVL_SEL;
+
+               if (flow_type & IRQF_TRIGGER_HIGH)
+                       chip->config[pmirq] &= ~PM_IRQF_MASK_RE;
+               else
+                       chip->config[pmirq] &= ~PM_IRQF_MASK_FE;
+       }
+
+       config = chip->config[pmirq] | PM_IRQF_CLR;
+       return pm8xxx_config_irq(chip, block, config);
+}
+
+static int pm8xxx_irq_set_wake(struct irq_data *d, unsigned int on)
+{
+       return 0;
+}
+
+static struct irq_chip pm8xxx_irq_chip = {
+       .name           = "pm8xxx",
+       .irq_mask_ack   = pm8xxx_irq_mask_ack,
+       .irq_unmask     = pm8xxx_irq_unmask,
+       .irq_set_type   = pm8xxx_irq_set_type,
+       .irq_set_wake   = pm8xxx_irq_set_wake,
+       .flags          = IRQCHIP_MASK_ON_SUSPEND,
+};
+
+/**
+ * pm8xxx_get_irq_stat - get the status of the irq line
+ * @chip: pointer to identify a pmic irq controller
+ * @irq: the irq number
+ *
+ * The pm8xxx gpio and mpp rely on the interrupt block to read
+ * the values on their pins. This function is to facilitate reading
+ * the status of a gpio or an mpp line. The caller has to convert the
+ * gpio number to irq number.
+ *
+ * RETURNS:
+ * an int indicating the value read on that line
+ */
+int pm8xxx_get_irq_stat(struct pm_irq_chip *chip, int irq)
+{
+       int pmirq, rc;
+       u8  block, bits, bit;
+       unsigned long flags;
+
+       if (chip == NULL || irq < chip->irq_base ||
+                       irq >= chip->irq_base + chip->num_irqs)
+               return -EINVAL;
+
+       pmirq = irq - chip->irq_base;
+
+       block = pmirq / 8;
+       bit = pmirq % 8;
+
+       spin_lock_irqsave(&chip->pm_irq_lock, flags);
+
+       rc = pm8xxx_writeb(chip->dev, SSBI_REG_ADDR_IRQ_BLK_SEL, block);
+       if (rc) {
+               pr_err("Failed Selecting block irq=%d pmirq=%d blk=%d rc=%d\n",
+                       irq, pmirq, block, rc);
+               goto bail_out;
+       }
+
+       rc = pm8xxx_readb(chip->dev, SSBI_REG_ADDR_IRQ_RT_STATUS, &bits);
+       if (rc) {
+               pr_err("Failed Configuring irq=%d pmirq=%d blk=%d rc=%d\n",
+                       irq, pmirq, block, rc);
+               goto bail_out;
+       }
+
+       rc = (bits & (1 << bit)) ? 1 : 0;
+
+bail_out:
+       spin_unlock_irqrestore(&chip->pm_irq_lock, flags);
+
+       return rc;
+}
+EXPORT_SYMBOL_GPL(pm8xxx_get_irq_stat);
+
+struct pm_irq_chip *  __devinit pm8xxx_irq_init(struct device *dev,
+                               const struct pm8xxx_irq_platform_data *pdata)
+{
+       struct pm_irq_chip  *chip;
+       int devirq, rc;
+       unsigned int pmirq;
+
+       if (!pdata) {
+               pr_err("No platform data\n");
+               return ERR_PTR(-EINVAL);
+       }
+
+       devirq = pdata->devirq;
+       if (devirq < 0) {
+               pr_err("missing devirq\n");
+               rc = devirq;
+               return ERR_PTR(-EINVAL);
+       }
+
+       chip = kzalloc(sizeof(struct pm_irq_chip)
+                       + sizeof(u8) * pdata->irq_cdata.nirqs, GFP_KERNEL);
+       if (!chip) {
+               pr_err("Cannot alloc pm_irq_chip struct\n");
+               return ERR_PTR(-EINVAL);
+       }
+
+       chip->dev = dev;
+       chip->devirq = devirq;
+       chip->irq_base = pdata->irq_base;
+       chip->num_irqs = pdata->irq_cdata.nirqs;
+       chip->num_blocks = DIV_ROUND_UP(chip->num_irqs, 8);
+       chip->num_masters = DIV_ROUND_UP(chip->num_blocks, 8);
+       spin_lock_init(&chip->pm_irq_lock);
+
+       for (pmirq = 0; pmirq < chip->num_irqs; pmirq++) {
+               irq_set_chip_and_handler(chip->irq_base + pmirq,
+                               &pm8xxx_irq_chip,
+                               handle_level_irq);
+               irq_set_chip_data(chip->irq_base + pmirq, chip);
+#ifdef CONFIG_ARM
+               set_irq_flags(chip->irq_base + pmirq, IRQF_VALID);
+#else
+               irq_set_noprobe(chip->irq_base + pmirq);
+#endif
+       }
+
+       irq_set_irq_type(devirq, pdata->irq_trigger_flag);
+       irq_set_handler_data(devirq, chip);
+       irq_set_chained_handler(devirq, pm8xxx_irq_handler);
+       set_irq_wake(devirq, 1);
+
+       return chip;
+}
+
+int __devexit pm8xxx_irq_exit(struct pm_irq_chip *chip)
+{
+       irq_set_chained_handler(chip->devirq, NULL);
+       kfree(chip);
+       return 0;
+}