35 lines
1.1 KiB
Diff
35 lines
1.1 KiB
Diff
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
|
|
Date: Thu, 21 Mar 2013 11:35:49 +0100
|
|
Subject: i2c/omap: drop the lock hard irq context
|
|
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.6/older/patches-4.6.2-rt5.tar.xz
|
|
|
|
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@linutronix.de>
|
|
---
|
|
drivers/i2c/busses/i2c-omap.c | 5 +----
|
|
1 file changed, 1 insertion(+), 4 deletions(-)
|
|
|
|
--- a/drivers/i2c/busses/i2c-omap.c
|
|
+++ b/drivers/i2c/busses/i2c-omap.c
|
|
@@ -995,15 +995,12 @@ omap_i2c_isr(int irq, void *dev_id)
|
|
u16 mask;
|
|
u16 stat;
|
|
|
|
- spin_lock(&omap->lock);
|
|
- mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG);
|
|
stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG);
|
|
+ mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG);
|
|
|
|
if (stat & mask)
|
|
ret = IRQ_WAKE_THREAD;
|
|
|
|
- spin_unlock(&omap->lock);
|
|
-
|
|
return ret;
|
|
}
|
|
|