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 <[email protected]> --- drivers/video/fbdev/omap2/dss/dispc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/video/fbdev/omap2/dss/dispc.c b/drivers/video/fbdev/omap2/dss/dispc.c index 4488d9367bd3..2db1c986e989 100644 --- a/drivers/video/fbdev/omap2/dss/dispc.c +++ b/drivers/video/fbdev/omap2/dss/dispc.c @@ -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); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
