From: Alex Deucher <alexander.deuc...@amd.com>
If there are error flags in the aux status, retry the transaction.
This makes aux much more reliable, especially on llano systems.
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Cc: stable at kernel.org
---
drivers/gpu/drm/radeon/atombios_dp.c | 12 +++++++++---
1 files changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/radeon/atombios_dp.c
b/drivers/gpu/drm/radeon/atombios_dp.c
index 4da2388..79e8ebc 100644
--- a/drivers/gpu/drm/radeon/atombios_dp.c
+++ b/drivers/gpu/drm/radeon/atombios_dp.c
@@ -129,7 +129,9 @@ static int radeon_dp_aux_native_write(struct
radeon_connector *radeon_connector,
for (retry = 0; retry < 4; retry++) {
ret = radeon_process_aux_ch(dig_connector->dp_i2c_bus,
msg, msg_bytes, NULL, 0, delay,
&ack);
- if (ret < 0)
+ if (ret == -EBUSY)
+ continue;
+ else if (ret < 0)
return ret;
if ((ack & AUX_NATIVE_REPLY_MASK) == AUX_NATIVE_REPLY_ACK)
return send_bytes;
@@ -160,7 +162,9 @@ static int radeon_dp_aux_native_read(struct
radeon_connector *radeon_connector,
for (retry = 0; retry < 4; retry++) {
ret = radeon_process_aux_ch(dig_connector->dp_i2c_bus,
msg, msg_bytes, recv, recv_bytes,
delay, &ack);
- if (ret < 0)
+ if (ret == -EBUSY)
+ continue;
+ else if (ret < 0)
return ret;
if ((ack & AUX_NATIVE_REPLY_MASK) == AUX_NATIVE_REPLY_ACK)
return ret;
@@ -236,7 +240,9 @@ int radeon_dp_i2c_aux_ch(struct i2c_adapter *adapter, int
mode,
for (retry = 0; retry < 4; retry++) {
ret = radeon_process_aux_ch(auxch,
msg, msg_bytes, reply, reply_bytes,
0, &ack);
- if (ret < 0) {
+ if (ret == -EBUSY)
+ continue;
+ else if (ret < 0) {
DRM_DEBUG_KMS("aux_ch failed %d\n", ret);
return ret;
}
--
1.7.1.1
