1 files changed, 37 insertions, 6 deletions

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 498a462c49b7..049331cebb7f 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -176,6 +176,7 @@ enum {
 #define I2C_OMAP_ERRATA_I462            (1 << 1)
 
 struct omap_i2c_dev {
+        spinlock_t              lock;           /* IRQ synchronization */
         struct device           *dev;
         void __iomem            *base;          /* virtual */
         int                     irq;
@@ -854,9 +855,30 @@ static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes,
 }
 
 static irqreturn_t
-omap_i2c_isr(int this_irq, void *dev_id)
+omap_i2c_isr(int irq, void *dev_id)
 {
         struct omap_i2c_dev *dev = dev_id;
+        irqreturn_t ret = IRQ_HANDLED;
+        u16 mask;
+        u16 stat;
+
+        spin_lock(&dev->lock);
+        mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
+        stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+
+        if (stat & mask)
+                ret = IRQ_WAKE_THREAD;
+
+        spin_unlock(&dev->lock);
+
+        return ret;
+}
+
+static irqreturn_t
+omap_i2c_isr_thread(int this_irq, void *dev_id)
+{
+        struct omap_i2c_dev *dev = dev_id;
+        unsigned long flags;
         u16 bits;
         u16 stat;
         int err = 0, count = 0;
@@ -864,6 +886,7 @@ omap_i2c_isr(int this_irq, void *dev_id)
         if (pm_runtime_suspended(dev->dev))
                 return IRQ_NONE;
 
+        spin_lock_irqsave(&dev->lock, flags);
         do {
                 bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
                 stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
@@ -877,6 +900,7 @@ omap_i2c_isr(int this_irq, void *dev_id)
 
                 if (!stat) {
                         /* my work here is done */
+                        spin_unlock_irqrestore(&dev->lock, flags);
                         return IRQ_HANDLED;
                 }
 
@@ -985,6 +1009,8 @@ omap_i2c_isr(int this_irq, void *dev_id)
 
 out:
         omap_i2c_complete_cmd(dev, err);
+        spin_unlock_irqrestore(&dev->lock, flags);
+
         return IRQ_HANDLED;
 }
 
@@ -1028,7 +1054,6 @@ omap_i2c_probe(struct platform_device *pdev)
         struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data;
         struct device_node      *node = pdev->dev.of_node;
         const struct of_device_id *match;
-        irq_handler_t isr;
         int irq;
         int r;
 
@@ -1078,6 +1103,8 @@ omap_i2c_probe(struct platform_device *pdev)
         dev->dev = &pdev->dev;
         dev->irq = irq;
 
+        spin_lock_init(&dev->lock);
+
         platform_set_drvdata(pdev, dev);
         init_completion(&dev->cmd_complete);
 
@@ -1130,10 +1157,14 @@ omap_i2c_probe(struct platform_device *pdev)
         /* reset ASAP, clearing any IRQs */
         omap_i2c_init(dev);
 
-        isr = (dev->rev < OMAP_I2C_OMAP1_REV_2) ? omap_i2c_omap1_isr :
-                                                                   omap_i2c_isr;
-        r = devm_request_irq(&pdev->dev, dev->irq, isr, IRQF_NO_SUSPEND,
-                             pdev->name, dev);
+        if (dev->rev < OMAP_I2C_OMAP1_REV_2)
+                r = devm_request_irq(&pdev->dev, dev->irq, omap_i2c_omap1_isr,
+                                IRQF_NO_SUSPEND, pdev->name, dev);
+        else
+                r = devm_request_threaded_irq(&pdev->dev, dev->irq,
+                                omap_i2c_isr, omap_i2c_isr_thread,
+                                IRQF_NO_SUSPEND | IRQF_ONESHOT,
+                                pdev->name, dev);
 
         if (r) {
                 dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);