From: David (Dingchen) Zhang Date: Fri, 6 Dec 2019 22:56:37 +0000 (-0500) Subject: drm: add dp helper to initialize remote aux channel. X-Git-Tag: v5.15~4520^2~15^2~3 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=c908b1c4bb56c27fa6fbb48e2d3dbebdad366706;p=platform%2Fkernel%2Flinux-starfive.git drm: add dp helper to initialize remote aux channel. [why] We need to minimally initialize the remote aux channel, e.g. the crc work struct of remote aux to dump the sink's DPRX CRCs in MST setup. [how] Add helper that only initializes the crc work struct of the remote aux, hooke crc work queue to 'drm_dp_aux_crc_work'. Then call this helper in DP MST port initialization. This, plus David Francis' patch [1], fix the issue of MST remote aux DPCD CRCs read. [1] https://patchwork.kernel.org/patch/11217941/ Cc: Leo Li Cc: Harry Wentland Signed-off-by: David (Dingchen) Zhang Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 374cedc..a5364b5 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -979,6 +979,19 @@ static void drm_dp_aux_crc_work(struct work_struct *work) } /** + * drm_dp_remote_aux_init() - minimally initialise a remote aux channel + * @aux: DisplayPort AUX channel + * + * Used for remote aux channel in general. Merely initialize the crc work + * struct. + */ +void drm_dp_remote_aux_init(struct drm_dp_aux *aux) +{ + INIT_WORK(&aux->crc_work, drm_dp_aux_crc_work); +} +EXPORT_SYMBOL(drm_dp_remote_aux_init); + +/** * drm_dp_aux_init() - minimally initialise an aux channel * @aux: DisplayPort AUX channel * diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index 7d174ba..fa06566 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -2200,6 +2200,9 @@ drm_dp_mst_add_port(struct drm_device *dev, port->aux.dev = dev->dev; port->aux.is_remote = true; + /* initialize the MST downstream port's AUX crc work queue */ + drm_dp_remote_aux_init(&port->aux); + /* * Make sure the memory allocation for our parent branch stays * around until our own memory allocation is released diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 0aeaf4a..bc04467 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -1465,6 +1465,7 @@ int drm_dp_downstream_id(struct drm_dp_aux *aux, char id[6]); void drm_dp_downstream_debug(struct seq_file *m, const u8 dpcd[DP_RECEIVER_CAP_SIZE], const u8 port_cap[4], struct drm_dp_aux *aux); +void drm_dp_remote_aux_init(struct drm_dp_aux *aux); void drm_dp_aux_init(struct drm_dp_aux *aux); int drm_dp_aux_register(struct drm_dp_aux *aux); void drm_dp_aux_unregister(struct drm_dp_aux *aux);