From 644a80508f918e488aad70814b65b7007438ef4c Mon Sep 17 00:00:00 2001 From: Lionel Landwerlin Date: Tue, 22 Mar 2016 14:10:33 +0000 Subject: [PATCH] drm: fix lut value extraction function When extracting the value at full precision (16 bits), no need to round the value. This was spotted by Jani when running sparse. Unfortunately this fix doesn't get rid of the warning. Signed-off-by: Lionel Landwerlin Reported-by: Jani Nikula Cc: Daniel Stone Cc: Daniel Vetter Cc: Matt Roper Cc: dri-devel@lists.freedesktop.org Fixes: 5488dc16fde7 ("drm: introduce pipe color correction properties") Reviewed-by: Emil Velikov Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1458655833-19547-1-git-send-email-lionel.g.landwerlin@intel.com --- include/drm/drm_crtc.h | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index 6d4684242a00..a6fbc9e5e896 100644 --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -2592,10 +2592,14 @@ static inline struct drm_property *drm_property_find(struct drm_device *dev, static inline uint32_t drm_color_lut_extract(uint32_t user_input, uint32_t bit_precision) { - uint32_t val = user_input + (1 << (16 - bit_precision - 1)); + uint32_t val = user_input; uint32_t max = 0xffff >> (16 - bit_precision); - val >>= 16 - bit_precision; + /* Round only if we're not using full precision. */ + if (bit_precision < 16) { + val += 1UL << (16 - bit_precision - 1); + val >>= 16 - bit_precision; + } return clamp_val(val, 0, max); } -- 2.20.1