[PATCH] Disable colour conversion in the CPiA Video Camera driver

Since in-kernel colorspace conversion is not allowed, this patch disables it
in the CPiA video camera driver by default.  Users should fix the applications
in case they don't work without conversion reenabled by setting the new
'colorspace_conv' module parameter to 1.  This is a temporary solution, so
within a few months deprecated code will be entirely removed.
Signed-off-by: Luca Risolia <luca.risolia@studio.unibo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/media/video/cpia.c

@@ -29,6 +29,7 @@
 #include <linux/config.h>
 
 #include <linux/module.h>
+#include <linux/moduleparam.h>
 #include <linux/init.h>
 #include <linux/fs.h>
 #include <linux/vmalloc.h>
@@ -62,6 +63,15 @@ MODULE_LICENSE("GPL");
 MODULE_SUPPORTED_DEVICE("video");
 #endif
 
+static unsigned short colorspace_conv = 0;
+module_param(colorspace_conv, ushort, 0444);
+MODULE_PARM_DESC(colorspace_conv,
+                 "\n<n> Colorspace conversion:"
+                 "\n0 = disable"
+                 "\n1 = enable"
+                 "\nDefault value is 0"
+                 "\n");
+
 #define ABOUT "V4L-Driver for Vision CPiA based cameras"
 
 #ifndef VID_HARDWARE_CPIA
@@ -1428,14 +1438,19 @@ static void __exit proc_cpia_destroy(void)
 /* supported frame palettes and depths */
 static inline int valid_mode(u16 palette, u16 depth)
 {
+	if ((palette == VIDEO_PALETTE_YUV422 && depth == 16) ||
+	    (palette == VIDEO_PALETTE_YUYV && depth == 16))
+		return 1;
+
+	if (colorspace_conv)
 		return (palette == VIDEO_PALETTE_GREY && depth == 8) ||
 		       (palette == VIDEO_PALETTE_RGB555 && depth == 16) ||
 		       (palette == VIDEO_PALETTE_RGB565 && depth == 16) ||
 		       (palette == VIDEO_PALETTE_RGB24 && depth == 24) ||
 		       (palette == VIDEO_PALETTE_RGB32 && depth == 32) ||
-	       (palette == VIDEO_PALETTE_YUV422 && depth == 16) ||
-	       (palette == VIDEO_PALETTE_YUYV && depth == 16) ||
 		       (palette == VIDEO_PALETTE_UYVY && depth == 16);
+
+	return 0;
 }
 
 static int match_videosize( int width, int height )
@@ -4040,6 +4055,13 @@ static int __init cpia_init(void)
 {
 	printk(KERN_INFO "%s v%d.%d.%d\n", ABOUT,
 	       CPIA_MAJ_VER, CPIA_MIN_VER, CPIA_PATCH_VER);
+
+	printk(KERN_WARNING "Since in-kernel colorspace conversion is not "
+	       "allowed, it is disabled by default now. Users should fix the "
+	       "applications in case they don't work without conversion "
+	       "reenabled by setting the 'colorspace_conv' module "
+	       "parameter to 1");
+
 #ifdef CONFIG_PROC_FS
 	proc_cpia_create();
 #endif