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Subject[PATCH v2 7/8] platform: sh_veu: use 64-bit arithmetic instead of 32-bit
Cast left and top to dma_addr_t in order to give the compiler complete
information about the proper arithmetic to use. Notice that these
variables are being used in contexts that expect expressions of
type dma_addr_t (64 bit, unsigned).

Such expressions are currently being evaluated using 32-bit arithmetic.

Also, move the expression (((dma_addr_t)left * veu->vfmt_out.fmt->depth) >> 3)
at the end in order to avoid a line wrapping checkpatch.pl warning.

Addresses-Coverity-ID: 1056807
Addresses-Coverity-ID: 1056808
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
Changes in v2:
- Update subject and changelog to better reflect the proposed code changes.
- Move the expression (((dma_addr_t)left * veu->vfmt_out.fmt->depth) >> 3)
at the end in order to avoid a line wrapping checkpatch.pl warning.

drivers/media/platform/sh_veu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/sh_veu.c b/drivers/media/platform/sh_veu.c
index 976ea0b..1a0cde0 100644
--- a/drivers/media/platform/sh_veu.c
+++ b/drivers/media/platform/sh_veu.c
@@ -520,8 +520,8 @@ static void sh_veu_colour_offset(struct sh_veu_dev *veu, struct sh_veu_vfmt *vfm
/* dst_left and dst_top validity will be verified in CROP / COMPOSE */
unsigned int left = vfmt->frame.left & ~0x03;
unsigned int top = vfmt->frame.top;
- dma_addr_t offset = ((left * veu->vfmt_out.fmt->depth) >> 3) +
- top * veu->vfmt_out.bytesperline;
+ dma_addr_t offset = (dma_addr_t)top * veu->vfmt_out.bytesperline +
+ (((dma_addr_t)left * veu->vfmt_out.fmt->depth) >> 3);
unsigned int y_line;

vfmt->offset_y = offset;
--
2.7.4
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