From 8265981bb439f3ecc5356fb877a6c2a6636ac88a Mon Sep 17 00:00:00 2001
From: Todd Poynor <toddpoynor@google.com>
Date: Fri, 13 Jul 2012 15:30:48 +0900
Subject: [PATCH] ARM: SAMSUNG: fix race in s3c_adc_start for ADC

Checking for adc->ts_pend already claimed should be done with the
lock held.

Signed-off-by: Todd Poynor <toddpoynor@google.com>
Acked-by: Ben Dooks <ben-linux@fluff.org>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
---
 arch/arm/plat-samsung/adc.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/arch/arm/plat-samsung/adc.c b/arch/arm/plat-samsung/adc.c
index 33ecd0c9f0c3..b1e05ccff3ac 100644
--- a/arch/arm/plat-samsung/adc.c
+++ b/arch/arm/plat-samsung/adc.c
@@ -157,11 +157,13 @@ int s3c_adc_start(struct s3c_adc_client *client,
 		return -EINVAL;
 	}
 
-	if (client->is_ts && adc->ts_pend)
-		return -EAGAIN;
-
 	spin_lock_irqsave(&adc->lock, flags);
 
+	if (client->is_ts && adc->ts_pend) {
+		spin_unlock_irqrestore(&adc->lock, flags);
+		return -EAGAIN;
+	}
+
 	client->channel = channel;
 	client->nr_samples = nr_samples;