[RFC/PATCH 1/3] i2c/omap: drop the lock hard irq context

Felipe Balbi balbi at ti.com
Thu Aug 1 08:12:43 EDT 2013


From: Sebastian Andrzej Siewior <bigeasy at linutronix.de>

The lock is taken while reading two registers. On RT the first lock is
taken in hard irq where it might sleep and in the threaded irq.
The threaded irq runs in oneshot mode so the hard irq does not run until
the thread the completes so there is no reason to grab the lock.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy at linutronix.de>
Signed-off-by: Felipe Balbi <balbi at ti.com>
---
 drivers/i2c/busses/i2c-omap.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 142b694d..8ceb98a 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -884,15 +884,12 @@ omap_i2c_isr(int irq, void *dev_id)
 	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);
+	mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
 
 	if (stat & mask)
 		ret = IRQ_WAKE_THREAD;
 
-	spin_unlock(&dev->lock);
-
 	return ret;
 }
 
-- 
1.8.3.4.840.g6a90778




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