i2c: xiic: move the xiic_process to thread context
authorShubhrajyoti Datta <shubhraj@xilinx.com>
Wed, 17 Jun 2015 15:18:12 +0000 (20:48 +0530)
committerWolfram Sang <wsa@the-dreams.de>
Mon, 10 Aug 2015 06:37:31 +0000 (08:37 +0200)
The xiic_process is a 154 line code that runs in isr context currently
move it to thread context. Also the name xiic_process suggests that the
intension was to run in process context.

Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com>
[wsa: initialized irqreturn_t to IRQ_NONE instead of IRQ_HANDLED]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
drivers/i2c/busses/i2c-xiic.c

index 912780a3a65ebf411f8bf7056133cdf57658ca35..3664dffdcab7316debf20e7e9d34094a87fdc75a 100644 (file)
@@ -358,8 +358,9 @@ static void xiic_wakeup(struct xiic_i2c *i2c, int code)
        wake_up(&i2c->wait);
 }
 
-static void xiic_process(struct xiic_i2c *i2c)
+static irqreturn_t xiic_process(int irq, void *dev_id)
 {
+       struct xiic_i2c *i2c = dev_id;
        u32 pend, isr, ier;
        u32 clr = 0;
 
@@ -368,6 +369,7 @@ static void xiic_process(struct xiic_i2c *i2c)
         * To find which interrupts are pending; AND interrupts pending with
         * interrupts masked.
         */
+       spin_lock(&i2c->lock);
        isr = xiic_getreg32(i2c, XIIC_IISR_OFFSET);
        ier = xiic_getreg32(i2c, XIIC_IIER_OFFSET);
        pend = isr & ier;
@@ -378,11 +380,6 @@ static void xiic_process(struct xiic_i2c *i2c)
                __func__, xiic_getreg8(i2c, XIIC_SR_REG_OFFSET),
                i2c->tx_msg, i2c->nmsgs);
 
-       /* Do not processes a devices interrupts if the device has no
-        * interrupts pending
-        */
-       if (!pend)
-               return;
 
        /* Service requesting interrupt */
        if ((pend & XIIC_INTR_ARB_LOST_MASK) ||
@@ -502,6 +499,8 @@ out:
        dev_dbg(i2c->adap.dev.parent, "%s clr: 0x%x\n", __func__, clr);
 
        xiic_setreg32(i2c, XIIC_IISR_OFFSET, clr);
+       spin_unlock(&i2c->lock);
+       return IRQ_HANDLED;
 }
 
 static int xiic_bus_busy(struct xiic_i2c *i2c)
@@ -602,16 +601,21 @@ static void xiic_start_send(struct xiic_i2c *i2c)
 static irqreturn_t xiic_isr(int irq, void *dev_id)
 {
        struct xiic_i2c *i2c = dev_id;
-
-       spin_lock(&i2c->lock);
+       u32 pend, isr, ier;
+       irqreturn_t ret = IRQ_NONE;
+       /* Do not processes a devices interrupts if the device has no
+        * interrupts pending
+        */
 
        dev_dbg(i2c->adap.dev.parent, "%s entry\n", __func__);
 
-       xiic_process(i2c);
-
-       spin_unlock(&i2c->lock);
+       isr = xiic_getreg32(i2c, XIIC_IISR_OFFSET);
+       ier = xiic_getreg32(i2c, XIIC_IIER_OFFSET);
+       pend = isr & ier;
+       if (pend)
+               ret = IRQ_WAKE_THREAD;
 
-       return IRQ_HANDLED;
+       return ret;
 }
 
 static void __xiic_start_xfer(struct xiic_i2c *i2c)
@@ -752,7 +756,10 @@ static int xiic_i2c_probe(struct platform_device *pdev)
        spin_lock_init(&i2c->lock);
        init_waitqueue_head(&i2c->wait);
 
-       ret = devm_request_irq(&pdev->dev, irq, xiic_isr, 0, pdev->name, i2c);
+       ret = devm_request_threaded_irq(&pdev->dev, irq, xiic_isr,
+                                       xiic_process, IRQF_ONESHOT,
+                                       pdev->name, i2c);
+
        if (ret < 0) {
                dev_err(&pdev->dev, "Cannot claim IRQ\n");
                return ret;