[PATCH 38/49] drm/i915: check for div-by-zero in vlv_PLL_is_optimal

Imre Deak
2015-03-17T09:40:55Z

Signed-off-by: Imre Deak <imre.deak@intel.com>
---
drivers/gpu/drm/i915/intel_display.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 7feb047..5874512 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -786,6 +786,9 @@ static bool vlv_PLL_is_optimal(struct drm_device *dev, int target_freq,
unsigned int best_error_ppm,
unsigned int *error_ppm)
{
+ if (WARN_ON_ONCE(!target_freq))
+ return false;
+
*error_ppm = div_u64(1000000ULL *
abs(target_freq - calculated_clock->dot),
target_freq);
--
2.1.0