From: Andrey Gusakov andrey.gusakov@cogentembedded.com
[ Upstream commit 9217c1abbc145a77d65c476cf2004a3df02104c7 ]
First four bytes should go to DP0_AUXWDATA0. Due to bug if len > 4 first four bytes was writen to DP0_AUXWDATA1 and all data get shifted by 4 bytes. Fix it.
Acked-by: Philipp Zabel p.zabel@pengutronix.de Signed-off-by: Andrey Gusakov andrey.gusakov@cogentembedded.com Signed-off-by: Andrzej Hajda a.hajda@samsung.com Link: https://patchwork.freedesktop.org/patch/msgid/1510073785-16108-6-git-send-em... Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- drivers/gpu/drm/bridge/tc358767.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c index 821b93f68eef..6d0772864935 100644 --- a/drivers/gpu/drm/bridge/tc358767.c +++ b/drivers/gpu/drm/bridge/tc358767.c @@ -318,7 +318,7 @@ static ssize_t tc_aux_transfer(struct drm_dp_aux *aux, tmp = (tmp << 8) | buf[i]; i++; if (((i % 4) == 0) || (i == size)) { - tc_write(DP0_AUXWDATA(i >> 2), tmp); + tc_write(DP0_AUXWDATA((i - 1) >> 2), tmp); tmp = 0; } }