public-mirrors/linux
1
0
Fork 0
mirror of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-08-05 16:54:27 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

OMAPDSS: DISPC: fix 64 bit issue in 5-tap

Browse source 
The DISPC driver uses 64 bit arithmetic to calculate the required clock
rate for scaling. The code does not seem to work correctly, and instead
calculates with 32 bit numbers, giving wrong result.

Fix the code by typecasting values to u64 first, so that the
calculations do happen in 64 bits.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
This commit is contained in:
Tomi Valkeinen 2015-04-10 12:48:36 +03:00
parent f2aee319d9
commit c582935c00
1 changed files with 3 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
drivers/video/fbdev/omap2/dss/dispc.c
View file

@ -2166,7 +2166,7 @@ static unsigned long calc_core_clk_five_taps(unsigned long pclk,
if (height > out_height) {
unsigned int ppl = mgr_timings->x_res;
tmp = pclk * height * out_width;
tmp = (u64)pclk * height * out_width;
do_div(tmp, 2 * out_height * ppl);
core_clk = tmp;
@ -2174,14 +2174,14 @@ static unsigned long calc_core_clk_five_taps(unsigned long pclk,
if (ppl == out_width)
return 0;
tmp = pclk * (height - 2 * out_height) * out_width;
tmp = (u64)pclk * (height - 2 * out_height) * out_width;
do_div(tmp, 2 * out_height * (ppl - out_width));
core_clk = max_t(u32, core_clk, tmp);
}
}
if (width > out_width) {
tmp = pclk * width;
tmp = (u64)pclk * width;
do_div(tmp, out_width);
core_clk = max_t(u32, core_clk, tmp);