Commit 167ffc44 authored by Dan Carpenter's avatar Dan Carpenter Committed by Dave Airlie

drm: radeon: fix sign bug

The "error" variable is unsigned so it's never less than zero.  I
changed it to check if (freq < current_freq) directly.

"best_error" is also unsigned so "best_error - 100" could be a large
number instead of a negative.  Since "error" is unsigned it is never
less than a negative and so the cases where "best_error" is less than or
equal to 100 are false.
Signed-off-by: default avatarDan Carpenter <error27@gmail.com>
Reviewed-by: default avatarAlex Deucher <alexdeucher@gmail.com>
Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
parent 4c712e6c
...@@ -558,15 +558,17 @@ static void radeon_compute_pll_legacy(struct radeon_pll *pll, ...@@ -558,15 +558,17 @@ static void radeon_compute_pll_legacy(struct radeon_pll *pll,
current_freq = radeon_div(tmp, ref_div * post_div); current_freq = radeon_div(tmp, ref_div * post_div);
if (pll->flags & RADEON_PLL_PREFER_CLOSEST_LOWER) { if (pll->flags & RADEON_PLL_PREFER_CLOSEST_LOWER) {
error = freq - current_freq; if (freq < current_freq)
error = error < 0 ? 0xffffffff : error; error = 0xffffffff;
else
error = freq - current_freq;
} else } else
error = abs(current_freq - freq); error = abs(current_freq - freq);
vco_diff = abs(vco - best_vco); vco_diff = abs(vco - best_vco);
if ((best_vco == 0 && error < best_error) || if ((best_vco == 0 && error < best_error) ||
(best_vco != 0 && (best_vco != 0 &&
(error < best_error - 100 || ((best_error > 100 && error < best_error - 100) ||
(abs(error - best_error) < 100 && vco_diff < best_vco_diff)))) { (abs(error - best_error) < 100 && vco_diff < best_vco_diff)))) {
best_post_div = post_div; best_post_div = post_div;
best_ref_div = ref_div; best_ref_div = ref_div;
......
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