2009-04-16 05:56:21

by Ben Nizette

[permalink] [raw]
Subject: [PATCH 4/9] sa1111ps2: Use disable_irq_nosync() from within irq handlers.


disable_irq() should wait for all running handlers to complete
before returning. As such, if it's used to disable an interrupt
from that interrupt's handler it will deadlock. This replaces
the dangerous instances with the _nosync() variant which doesn't
have this problem.

Signed-off-by: Ben Nizette <[email protected]>
---
diff --git a/drivers/input/serio/sa1111ps2.c b/drivers/input/serio/sa1111ps2.c
index 57953c0..f412c69 100644
--- a/drivers/input/serio/sa1111ps2.c
+++ b/drivers/input/serio/sa1111ps2.c
@@ -77,7 +77,7 @@ static irqreturn_t ps2_txint(int irq, void *dev_id)
spin_lock(&ps2if->lock);
status = sa1111_readl(ps2if->base + SA1111_PS2STAT);
if (ps2if->head == ps2if->tail) {
- disable_irq(irq);
+ disable_irq_nosync(irq);
/* done */
} else if (status & PS2STAT_TXE) {
sa1111_writel(ps2if->buf[ps2if->tail], ps2if->base + SA1111_PS2DATA);
--
1.6.0.2