4.17-stable review patch. If anyone has any objections, please let me know.
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From: Alex Deucher alexander.deucher@amd.com
commit 5292221d6ddfed75e5b46cd42237a677094b99f3 upstream.
This reverts commit 018d82e5f02ef3583411bcaa4e00c69786f46f19.
This breaks DDC in certain cases. Revert for 4.18 and previous kernels. For 4.19, this is fixed with the following more extensive patches: drm/amd/display: Serialize is_dp_sink_present drm/amd/display: Break out function to simply read aux reply drm/amd/display: Return aux replies directly to DRM drm/amd/display: Right shift AUX reply value sooner than later drm/amd/display: Read AUX channel even if only status byte is returned
Link: https://lists.freedesktop.org/archives/amd-gfx/2018-July/023788.html Acked-by: Harry Wentland harry.wentland@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c | 20 ++++-------- drivers/gpu/drm/amd/display/dc/core/dc_link_ddc.c | 10 +----- drivers/gpu/drm/amd/display/dc/inc/dc_link_ddc.h | 5 +-- 3 files changed, 13 insertions(+), 22 deletions(-)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c @@ -83,22 +83,21 @@ static ssize_t dm_dp_aux_transfer(struct enum i2c_mot_mode mot = (msg->request & DP_AUX_I2C_MOT) ? I2C_MOT_TRUE : I2C_MOT_FALSE; enum ddc_result res; - uint32_t read_bytes = msg->size; + ssize_t read_bytes;
if (WARN_ON(msg->size > 16)) return -E2BIG;
switch (msg->request & ~DP_AUX_I2C_MOT) { case DP_AUX_NATIVE_READ: - res = dal_ddc_service_read_dpcd_data( + read_bytes = dal_ddc_service_read_dpcd_data( TO_DM_AUX(aux)->ddc_service, false, I2C_MOT_UNDEF, msg->address, msg->buffer, - msg->size, - &read_bytes); - break; + msg->size); + return read_bytes; case DP_AUX_NATIVE_WRITE: res = dal_ddc_service_write_dpcd_data( TO_DM_AUX(aux)->ddc_service, @@ -109,15 +108,14 @@ static ssize_t dm_dp_aux_transfer(struct msg->size); break; case DP_AUX_I2C_READ: - res = dal_ddc_service_read_dpcd_data( + read_bytes = dal_ddc_service_read_dpcd_data( TO_DM_AUX(aux)->ddc_service, true, mot, msg->address, msg->buffer, - msg->size, - &read_bytes); - break; + msg->size); + return read_bytes; case DP_AUX_I2C_WRITE: res = dal_ddc_service_write_dpcd_data( TO_DM_AUX(aux)->ddc_service, @@ -139,9 +137,7 @@ static ssize_t dm_dp_aux_transfer(struct r == DDC_RESULT_SUCESSFULL); #endif
- if (res != DDC_RESULT_SUCESSFULL) - return -EIO; - return read_bytes; + return msg->size; }
static enum drm_connector_status --- a/drivers/gpu/drm/amd/display/dc/core/dc_link_ddc.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_ddc.c @@ -629,14 +629,13 @@ bool dal_ddc_service_query_ddc_data( return ret; }
-enum ddc_result dal_ddc_service_read_dpcd_data( +ssize_t dal_ddc_service_read_dpcd_data( struct ddc_service *ddc, bool i2c, enum i2c_mot_mode mot, uint32_t address, uint8_t *data, - uint32_t len, - uint32_t *read) + uint32_t len) { struct aux_payload read_payload = { .i2c_over_aux = i2c, @@ -653,8 +652,6 @@ enum ddc_result dal_ddc_service_read_dpc .mot = mot };
- *read = 0; - if (len > DEFAULT_AUX_MAX_DATA_SIZE) { BREAK_TO_DEBUGGER(); return DDC_RESULT_FAILED_INVALID_OPERATION; @@ -664,8 +661,7 @@ enum ddc_result dal_ddc_service_read_dpc ddc->ctx->i2caux, ddc->ddc_pin, &command)) { - *read = command.payloads->length; - return DDC_RESULT_SUCESSFULL; + return (ssize_t)command.payloads->length; }
return DDC_RESULT_FAILED_OPERATION; --- a/drivers/gpu/drm/amd/display/dc/inc/dc_link_ddc.h +++ b/drivers/gpu/drm/amd/display/dc/inc/dc_link_ddc.h @@ -102,14 +102,13 @@ bool dal_ddc_service_query_ddc_data( uint8_t *read_buf, uint32_t read_size);
-enum ddc_result dal_ddc_service_read_dpcd_data( +ssize_t dal_ddc_service_read_dpcd_data( struct ddc_service *ddc, bool i2c, enum i2c_mot_mode mot, uint32_t address, uint8_t *data, - uint32_t len, - uint32_t *read); + uint32_t len);
enum ddc_result dal_ddc_service_write_dpcd_data( struct ddc_service *ddc,