[PATCH] drm/mgag200: Fix type of dividend in do_div()

From: Thierry Reding
Date: Thu Oct 02 2014 - 03:29:54 EST


From: Thierry Reding <treding@xxxxxxxxxx>

The semantics of do_div() are (see include/asm-generic/do_div.h):

uint32_t do_div(uint64_t *n, uint32_t base)

Using a different type will therefore cause the following warning (as
seen on xtensa/allmodconfig):

CC [M] drivers/gpu/drm/mgag200/mgag200_mode.o
In file included from arch/xtensa/include/generated/asm/div64.h:1:0,
from include/linux/kernel.h:124,
from include/linux/delay.h:10,
from drivers/gpu/drm/mgag200/mgag200_mode.c:14:
drivers/gpu/drm/mgag200/mgag200_mode.c: In function 'mga_vga_calculate_mode_bandwidth':
include/asm-generic/div64.h:43:28: warning: comparison of distinct pointer types lacks a cast
(void)(((typeof((n)) *)0) == ((uint64_t *)0)); \
^
drivers/gpu/drm/mgag200/mgag200_mode.c:1471:2: note: in expansion of macro 'do_div'
do_div(pixels_per_second, total_area);
^
include/asm-generic/div64.h:43:28: warning: comparison of distinct pointer types lacks a cast
(void)(((typeof((n)) *)0) == ((uint64_t *)0)); \
^
drivers/gpu/drm/mgag200/mgag200_mode.c:1474:2: note: in expansion of macro 'do_div'
do_div(bandwidth, divisor);
^

Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
---
drivers/gpu/drm/mgag200/mgag200_mode.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
index 83485ab81ce8..4d519dc99db8 100644
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
@@ -1455,9 +1455,9 @@ static int mga_vga_get_modes(struct drm_connector *connector)
static uint32_t mga_vga_calculate_mode_bandwidth(struct drm_display_mode *mode,
int bits_per_pixel)
{
- uint32_t total_area, divisor;
- int64_t active_area, pixels_per_second, bandwidth;
uint64_t bytes_per_pixel = (bits_per_pixel + 7) / 8;
+ uint32_t total_area, divisor, active_area;
+ uint64_t pixels_per_second, bandwidth;

divisor = 1024;

--
2.1.0

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