V4L: saa7146: Fix allocation of clipping memory

V4L: saa7146: Fix allocation of clipping memory

Olaf Hering pointed out that SAA7146_CLIPPING_MEM would become
very large for PAGE_SIZE > 4K.

In fact, the number of clipping windows is limited to 16,
and calculate_clipping_registers_rect() does not use more
than 256 bytes. SAA7146_CLIPPING_MEM adjusted accordingly.

(cherry picked from commit 7a7cd1920969dd9da4e0d99aab573b3eba24c799)

Thanks-to: Olaf Hering <olaf@aepfle.de>
Acked-by: Michael Hunold <hunold@linuxtv.org>
Signed-off-by: Oliver Endriss <o.endriss@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/include/media/saa7146_vv.h b/include/media/saa7146_vv.h
index 83fe2e3d1e25a43d1c3fefcab1255baf1194ea30..50e33b0e934984c543651bf4cb1fd8b3af550c87 100644 (file)
--- a/include/media/saa7146_vv.h
+++ b/include/media/saa7146_vv.h
@@ -239,7 +239,8 @@ void saa7146_res_free(struct saa7146_fh *fh, unsigned int bits);
 #define SAA7146_HPS_SYNC_PORT_B                0x01
 
 /* some memory sizes */
-#define SAA7146_CLIPPING_MEM   (14*PAGE_SIZE)
+/* max. 16 clipping rectangles */
+#define SAA7146_CLIPPING_MEM   (16 * 4 * sizeof(u32))
 
 /* some defines for the various clipping-modes */
 #define SAA7146_CLIPPING_RECT          0x4