openwrtv4/target/linux/brcm2708/patches-3.10/0067-Avoid-responding-to-unexpected-I2C-interrupts.patch

From ed5a728f2593fbd3950c5c17ab7143bafc295e57 Mon Sep 17 00:00:00 2001
From: popcornmix <popcornmix@gmail.com>
Date: Thu, 13 Jun 2013 16:46:54 +0100
Subject: [PATCH 067/196] Avoid responding to unexpected I2C interrupts

---
 drivers/i2c/busses/i2c-bcm2708.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/i2c/busses/i2c-bcm2708.c b/drivers/i2c/busses/i2c-bcm2708.c
index edc90c0..33f4e7d 100644
--- a/drivers/i2c/busses/i2c-bcm2708.c
+++ b/drivers/i2c/busses/i2c-bcm2708.c
@@ -175,6 +175,11 @@ static irqreturn_t bcm2708_i2c_interrupt(int irq, void *dev_id)
 
 	spin_lock(&bi->lock);
 
+	/* we may see camera interrupts on the "other" I2C channel
+           Just return if we've not sent anything */
+        if (!bi->nmsgs || !bi->msg )
+		goto early_exit;
+
 	s = bcm2708_rd(bi, BSC_S);
 
 	if (s & (BSC_S_CLKT | BSC_S_ERR)) {
@@ -208,6 +213,7 @@ static irqreturn_t bcm2708_i2c_interrupt(int irq, void *dev_id)
 		handled = false;
 	}
 
+early_exit:
 	spin_unlock(&bi->lock);
 
 	return handled ? IRQ_HANDLED : IRQ_NONE;
-- 
1.9.1