From: Dave Airlie <airl...@redhat.com>
If we get a msg.reply of REPLY_DEFER, we also get an err of 0
so we fail reads with 0 < size and return -EPROTO instead of trying
again.
v2: same fix in i2c code.
Found writing MST support.
Signed-off-by: Dave Airlie <airlied at redhat.com>
---
drivers/gpu/drm/drm_dp_helper.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index f4babed..2767148 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -386,11 +386,11 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8
request,
return err;
}
- if (err < size)
- return -EPROTO;
switch (msg.reply & DP_AUX_NATIVE_REPLY_MASK) {
case DP_AUX_NATIVE_REPLY_ACK:
+ if (err < size)
+ return -EPROTO;
return err;
case DP_AUX_NATIVE_REPLY_NACK:
@@ -599,8 +599,6 @@ static int drm_dp_i2c_do_msg(struct drm_dp_aux *aux, struct
drm_dp_aux_msg *msg)
return err;
}
- if (err < msg->size)
- return -EPROTO;
switch (msg->reply & DP_AUX_NATIVE_REPLY_MASK) {
case DP_AUX_NATIVE_REPLY_ACK:
@@ -639,6 +637,8 @@ static int drm_dp_i2c_do_msg(struct drm_dp_aux *aux, struct
drm_dp_aux_msg *msg)
* Both native ACK and I2C ACK replies received. We
* can assume the transfer was successful.
*/
+ if (err < msg->size)
+ return -EPROTO;
return 0;
case DP_AUX_I2C_REPLY_NACK:
--
1.8.5.3
