From ccddd5d32048876bd1fbc79663238f7a712921b8 Mon Sep 17 00:00:00 2001 From: Anthony Koo Date: Wed, 6 Feb 2019 11:45:42 -0500 Subject: [PATCH 1301/2940] drm/amd/display: Fix exception from AUX acquire failure [Why] AUX arbitration occurs between SW and FW components. When AUX acquire fails, it causes engine->ddc to be NULL, which leads to an exception when we try to release the AUX engine. [How] When AUX engine acquire fails, it should return from the function without trying to continue the operation. The upper level will determine if it wants to retry. i.e. dce_aux_transfer_with_retries will be used and retry. Signed-off-by: Anthony Koo Reviewed-by: Aric Cyr Acked-by: Leo Li --- drivers/gpu/drm/amd/display/dc/dce/dce_aux.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c b/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c index 4febf4ef7240..2f50be33ab15 100644 --- a/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c +++ b/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c @@ -374,7 +374,6 @@ static bool acquire( struct dce_aux *engine, struct ddc *ddc) { - enum gpio_result result; if (!is_engine_available(engine)) @@ -455,7 +454,8 @@ int dce_aux_transfer(struct ddc_service *ddc, memset(&aux_rep, 0, sizeof(aux_rep)); aux_engine = ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en]; - acquire(aux_engine, ddc_pin); + if (!acquire(aux_engine, ddc_pin)) + return -1; if (payload->i2c_over_aux) aux_req.type = AUX_TRANSACTION_TYPE_I2C; -- 2.17.1