V4L/DVB (3195): Fix for 64-bit compile warning

- Add the fix for the saa7146 64-bit compile warning (again). This time with
comments and checked by Johannes Stezenbach.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>

diff --git a/drivers/media/common/saa7146_hlp.c b/drivers/media/common/saa7146_hlp.c
index ec52dff8cb695a35fb72687b1aa508c5196b1b97..33bec8a6843b49bdc05ec9345326bad23a316a11 100644 (file)
--- a/drivers/media/common/saa7146_hlp.c
+++ b/drivers/media/common/saa7146_hlp.c
@@ -562,19 +562,26 @@ static void saa7146_set_position(struct saa7146_dev *dev, int w_x, int w_y, int
 
        int b_depth = vv->ov_fmt->depth;
        int b_bpl = vv->ov_fb.fmt.bytesperline;
-       u32 base = (u32)vv->ov_fb.base;
+       /* The unsigned long cast is to remove a 64-bit compile warning since
+          it looks like a 64-bit address is cast to a 32-bit value, even
+          though the base pointer is really a 32-bit physical address that
+          goes into a 32-bit DMA register.
+          FIXME: might not work on some 64-bit platforms, but see the FIXME
+          in struct v4l2_framebuffer (videodev2.h) for that.
+        */
+       u32 base = (u32)(unsigned long)vv->ov_fb.base;
 
        struct  saa7146_video_dma vdma1;
 
        /* calculate memory offsets for picture, look if we shall top-down-flip */
        vdma1.pitch     = 2*b_bpl;
        if ( 0 == vv->vflip ) {
-               vdma1.base_even = (u32)base + (w_y * (vdma1.pitch/2)) + (w_x * (b_depth / 8));
+               vdma1.base_even = base + (w_y * (vdma1.pitch/2)) + (w_x * (b_depth / 8));
                vdma1.base_odd  = vdma1.base_even + (vdma1.pitch / 2);
                vdma1.prot_addr = vdma1.base_even + (w_height * (vdma1.pitch / 2));
        }
        else {
-               vdma1.base_even = (u32)base + ((w_y+w_height) * (vdma1.pitch/2)) + (w_x * (b_depth / 8));
+               vdma1.base_even = base + ((w_y+w_height) * (vdma1.pitch/2)) + (w_x * (b_depth / 8));
                vdma1.base_odd  = vdma1.base_even - (vdma1.pitch / 2);
                vdma1.prot_addr = vdma1.base_odd - (w_height * (vdma1.pitch / 2));
        }