i2c: omap: switch to threaded IRQ support
for OMAP2, we can easily switch over to threaded
IRQs on the I2C driver. This will allow us to
spend less time in hardirq context.
Signed-off-by: Felipe Balbi <balbi@ti.com>
[Trivial formating changes]
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 498a462..049331c 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -176,6 +176,7 @@
#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 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 @@
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 @@
if (!stat) {
/* my work here is done */
+ spin_unlock_irqrestore(&dev->lock, flags);
return IRQ_HANDLED;
}
@@ -985,6 +1009,8 @@
out:
omap_i2c_complete_cmd(dev, err);
+ spin_unlock_irqrestore(&dev->lock, flags);
+
return IRQ_HANDLED;
}
@@ -1028,7 +1054,6 @@
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 @@
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 @@
/* 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);