From: xiazhengqiao Date: Thu, 21 Dec 2023 09:30:57 +0000 (+0800) Subject: drm/bridge: Fixed a DP link training bug X-Git-Tag: v6.9-rc1~126^2~24^2~8 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ca077ff8cac5af8a5a3c476983a6dd54aa3511b7;p=thirdparty%2Flinux.git drm/bridge: Fixed a DP link training bug To have better compatibility for DP sink, there is a retry mechanism for the link training process to switch between different training process. The original driver code doesn't reset the retry counter when training state is pass. If the system triggers link training over 3 times, there will be a chance to causes the driver to use the wrong training method and return a training fail result. To Fix this, we reset the retry counter when training state is pass each time. Signed-off-by: Allen Chen Signed-off-by: xiazhengqiao Reviewed-by: Robert Foss Signed-off-by: Robert Foss Link: https://patchwork.freedesktop.org/patch/msgid/20231221093057.7073-1-xiazhengqiao@huaqin.corp-partner.google.com --- diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c index 2f300f5ca051c..b589136ca6da9 100644 --- a/drivers/gpu/drm/bridge/ite-it6505.c +++ b/drivers/gpu/drm/bridge/ite-it6505.c @@ -2240,11 +2240,13 @@ static void it6505_link_training_work(struct work_struct *work) ret = it6505_link_start_auto_train(it6505); DRM_DEV_DEBUG_DRIVER(dev, "auto train %s, auto_train_retry: %d", ret ? "pass" : "failed", it6505->auto_train_retry); - it6505->auto_train_retry--; if (ret) { + it6505->auto_train_retry = AUTO_TRAIN_RETRY; it6505_link_train_ok(it6505); return; + } else { + it6505->auto_train_retry--; } it6505_dump(it6505);