On Wed, Mar 26, 2025 at 01:34:17PM +0800, Hermes Wu via B4 Relay wrote:
> From: Hermes Wu <hermes...@ite.com.tw>
>
> When connect to device which can only training done by
> step training, skip auto training when link training restart,
> usually happen when display resolution is changed.
>
> Signed-off-by: Hermes Wu <hermes...@ite.com.tw>
> ---
> drivers/gpu/drm/bridge/ite-it6505.c | 29 +++++++++++++++++------------
> 1 file changed, 17 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/ite-it6505.c
> b/drivers/gpu/drm/bridge/ite-it6505.c
> index
> 2bbe787ccb1b57906f2a31a011dd92f327019b08..47f8134df8b6f5c2172c6cfdbc91da8063993a05
> 100644
> --- a/drivers/gpu/drm/bridge/ite-it6505.c
> +++ b/drivers/gpu/drm/bridge/ite-it6505.c
> @@ -467,6 +467,7 @@ struct it6505 {
> struct delayed_work hdcp_work;
> struct work_struct hdcp_wait_ksv_list;
> struct completion extcon_completion;
> + u8 step_train_only;
> bool hdcp_desired;
> bool is_repeater;
> u8 hdcp_down_stream_count;
> @@ -2457,11 +2458,13 @@ static void it6505_link_step_train_process(struct
> it6505 *it6505)
> ret ? "pass" : "failed", i + 1);
> if (ret) {
> it6505_link_train_ok(it6505);
> + it6505->step_train_only = true;
> return;
> }
> }
>
> DRM_DEV_DEBUG_DRIVER(dev, "training fail");
> + it6505->step_train_only = false;
> it6505->link_state = LINK_IDLE;
> it6505_video_reset(it6505);
> }
> @@ -2477,18 +2480,19 @@ static void it6505_link_training_work(struct
> work_struct *work)
>
> if (!it6505_get_sink_hpd_status(it6505))
> return;
> -
> - for (retry = AUTO_TRAIN_RETRY; retry > 0; retry--) {
> - it6505_link_training_setup(it6505);
> - it6505_reset_hdcp(it6505);
> - it6505_aux_reset(it6505);
> -
> - ret = it6505_link_start_auto_train(it6505);
> - DRM_DEV_DEBUG_DRIVER(dev, "auto train %s,",
> - ret ? "pass" : "failed");
> - if (ret) {
> - it6505_link_train_ok(it6505);
> - return;
> + if (!it6505->step_train_only) {
No need to. Just
for (retry = AUTO_TRAIN_RETRY; retry > 0 &&
!it6505->step_train_only; retry--) {
> + for (retry = AUTO_TRAIN_RETRY; retry > 0; retry--) {
> + it6505_link_training_setup(it6505);
> + it6505_reset_hdcp(it6505);
> + it6505_aux_reset(it6505);
> +
> + ret = it6505_link_start_auto_train(it6505);
> + DRM_DEV_DEBUG_DRIVER(dev, "auto train %s,",
> + ret ? "pass" : "failed");
> + if (ret) {
> + it6505_link_train_ok(it6505);
> + return;
> + }
> }
> }
>
> @@ -2599,6 +2603,7 @@ static void it6505_irq_hpd(struct it6505 *it6505)
> it6505_variable_config(it6505);
> it6505_parse_link_capabilities(it6505);
> }
> + it6505->step_train_only = false;
>
> it6505_drm_dp_link_set_power(&it6505->aux, &it6505->link,
> DP_SET_POWER_D0);
>
> --
> 2.34.1
>
>
--
With best wishes
Dmitry
