From: Hartmut Birr <e9hack@googlemail.com>
Date: Wed, 1 Nov 2006 15:46:32 +0000 (-0300)
Subject: V4L/DVB (4914): Saa7146: Protect access to the IER register by a spinlock
X-Git-Tag: v2.6.20-rc1~145^2~5^2~38
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=88bbdf74fcfa7ed1fd1a3c825ee5575752344326;p=linux-2.6

V4L/DVB (4914): Saa7146: Protect access to the IER register by a spinlock

Protect the access to the IER register of the SAA7146 by the device
spinlock. I2C transfers may use interrupt mode now.

Signed-off-by: Oliver Endriss <o.endriss@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
---

diff --git a/include/media/saa7146.h b/include/media/saa7146.h
index fee579f10b..afa5ff6469 100644
--- a/include/media/saa7146.h
+++ b/include/media/saa7146.h
@@ -42,10 +42,20 @@ extern unsigned int saa7146_debug;
 #define DEB_INT(x)  if (0!=(DEBUG_VARIABLE&0x20)) { DEBUG_PROLOG; printk x; } /* interrupt debug messages */
 #define DEB_CAP(x)  if (0!=(DEBUG_VARIABLE&0x40)) { DEBUG_PROLOG; printk x; } /* capture debug messages */
 
-#define SAA7146_IER_DISABLE(x,y) \
-	saa7146_write(x, IER, saa7146_read(x, IER) & ~(y));
-#define SAA7146_IER_ENABLE(x,y) \
-	saa7146_write(x, IER, saa7146_read(x, IER) | (y));
+#define SAA7146_IER_DISABLE(x,y) 					\
+	do { 								\
+		unsigned int flags; 					\
+		spin_lock_irqsave(&x->int_slock, flags); 		\
+		saa7146_write(x, IER, saa7146_read(x, IER) & ~(y));	\
+		spin_unlock_irqrestore(&x->int_slock, flags);		\
+	} while(0)
+#define SAA7146_IER_ENABLE(x,y)						\
+	do { 								\
+		unsigned int flags; 					\
+		spin_lock_irqsave(&x->int_slock, flags); 		\
+		saa7146_write(x, IER, saa7146_read(x, IER) | (y));	\
+		spin_unlock_irqrestore(&x->int_slock, flags);		\
+	} while(0)
 #define SAA7146_ISR_CLEAR(x,y) \
 	saa7146_write(x, ISR, (y));