drm_dp_link_rate_to_bw_code and ...bw_code_to_link_rate simply divide by and multiply with 27000, respectively. Avoid an overflow in the u8 dpcd[0] and the multiply+divide alltogether.
fixes: e1cff82c1097bda2478 ("fix anx6345 compilation for v5.5") Signed-off-by: Torsten Duwe duwe@suse.de --- https://patchwork.freedesktop.org/patch/343004/ https://lists.freedesktop.org/archives/dri-devel/2020-January/253535.html
Can someone please review this? It's equivalent to commit 3e138a63d6674a4567a018a31 which just made it into drm-tip.
--- a/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c +++ b/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c @@ -210,10 +210,9 @@ static int anx6345_dp_link_training(struct anx6345 *anx6345) if (err) return err;
- dpcd[0] = drm_dp_max_link_rate(anx6345->dpcd); - dpcd[0] = drm_dp_link_rate_to_bw_code(dpcd[0]); err = regmap_write(anx6345->map[I2C_IDX_DPTX], - SP_DP_MAIN_LINK_BW_SET_REG, dpcd[0]); + SP_DP_MAIN_LINK_BW_SET_REG, + anx6345->dpcd[DP_MAX_LINK_RATE]); if (err) return err;