From: Felipe Balbi <balbi@xxxxxx>
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@xxxxxx>
[Trivial formating changes]
Signed-off-by: Shubhrajyoti D <shubhrajyoti@xxxxxx>
---
drivers/i2c/busses/i2c-omap.c | 43 +++++++++++++++++++++++++++++++++++-----
1 files changed, 37 insertions(+), 6 deletions(-)
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index f5eafb7..39e5d36 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_HANDLED;
+ 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);
--
1.7.5.4
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