| From 4f332844cc87c5f99c5300f788abbe8a8c731390 Mon Sep 17 00:00:00 2001 |
| From: Alex Deucher <alexander.deucher@amd.com> |
| Date: Tue, 4 Oct 2011 17:23:15 -0400 |
| Subject: drm/radeon/kms: retry aux transactions if there are status flags |
| MIME-Version: 1.0 |
| Content-Type: text/plain; charset=UTF-8 |
| Content-Transfer-Encoding: 8bit |
| |
| From: Alex Deucher <alexander.deucher@amd.com> |
| |
| commit 4f332844cc87c5f99c5300f788abbe8a8c731390 upstream. |
| |
| 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@amd.com> |
| Reviewed-by: Michel Dรคnzer <michel.daenzer@amd.com> |
| Signed-off-by: Dave Airlie <airlied@redhat.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| |
| --- |
| drivers/gpu/drm/radeon/atombios_dp.c | 12 +++++++++--- |
| 1 file changed, 9 insertions(+), 3 deletions(-) |
| |
| --- 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(st |
| 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(str |
| 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_adap |
| 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; |
| } |
