35 lines
1.1 KiB
Diff
35 lines
1.1 KiB
Diff
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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Date: Thu, 21 Mar 2013 11:35:49 +0100
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Subject: i2c/omap: drop the lock hard irq context
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Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.4-rc6-rt1/patches-4.4-rc6-rt1.tar.xz
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The lock is taken while reading two registers. On RT the first lock is
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taken in hard irq where it might sleep and in the threaded irq.
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The threaded irq runs in oneshot mode so the hard irq does not run until
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the thread the completes so there is no reason to grab the lock.
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Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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---
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drivers/i2c/busses/i2c-omap.c | 5 +----
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1 file changed, 1 insertion(+), 4 deletions(-)
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--- a/drivers/i2c/busses/i2c-omap.c
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+++ b/drivers/i2c/busses/i2c-omap.c
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@@ -995,15 +995,12 @@ omap_i2c_isr(int irq, void *dev_id)
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u16 mask;
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u16 stat;
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- spin_lock(&omap->lock);
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- mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG);
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stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG);
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+ mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG);
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if (stat & mask)
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ret = IRQ_WAKE_THREAD;
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- spin_unlock(&omap->lock);
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-
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return ret;
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}
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