From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6AE7CC433EF for ; Sat, 18 Sep 2021 07:25:40 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CF5A2610E9 for ; Sat, 18 Sep 2021 07:25:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org CF5A2610E9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=uniontech.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 565136E0DB; Sat, 18 Sep 2021 07:25:36 +0000 (UTC) X-Greylist: delayed 429 seconds by postgrey-1.36 at gabe; Sat, 18 Sep 2021 03:58:39 UTC Received: from qq.com (smtpbg465.qq.com [59.36.132.35]) by gabe.freedesktop.org (Postfix) with ESMTPS id A59886E0D5 for ; Sat, 18 Sep 2021 03:58:39 +0000 (UTC) X-QQ-mid: bizesmtp44t1631937068tuf7vu0i Received: from localhost.localdomain (unknown [124.126.19.250]) by esmtp6.qq.com (ESMTP) with id ; Sat, 18 Sep 2021 11:51:06 +0800 (CST) X-QQ-SSF: 0140000000000050D000000B0000000 X-QQ-FEAT: OKkEFpVJhAgeOo+4wBV1a8svT7hEZbnr9Q8DIBXJHVG4F7VfEjlVBvIJQ4rhj iOeinhXzceJDjLrohQuz6dsPqstmrPfiWgPEEqh8CvsUG7WX2kGTUc8RbcBruycYeJlrU6W cJ9xE1JAtkTDpQlcPLUVnGNEkYO0tOkdfHZdUgxel2PPeuwe+ogreu0IUW0OIaHyOe+NfM3 rBs4pWIA73WDPrqlUVnkXRz+xu04nQsevwwp4SIa99f4oAMFR1Lg9KeMi4XrjIngnrcfgbb QjxLe5XY0w8/WO8R9ul/+/wsDafr6f9tmQ9Nw2NRpAF/QflMyvS3IAw9f4R/bdLO5sXOvnv dSS5fIa7eTqRPDxAYX72gqdP/MIYA== X-QQ-GoodBg: 1 From: Yunlongli To: ple@baylibre.com, narmstrong@baylibre.com, a.hajda@samsung.com, robert.foss@linaro.org, airlied@linux.ie, daniel@ffwll.ch Cc: Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, liyunlonga@uniontech.com Subject: [PATCH] drm: bridge: it66121: Added it66121 chip external screen status judgment. Date: Sat, 18 Sep 2021 11:50:41 +0800 Message-Id: <20210918035041.25512-1-liyunlonga@uniontech.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-QQ-SENDSIZE: 520 Feedback-ID: bizesmtp:uniontech.com:qybgforeign:qybgforeign1 X-QQ-Bgrelay: 1 X-Mailman-Approved-At: Sat, 18 Sep 2021 07:25:35 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" fix: Add further confirm if external screens are involved. log: In the actual tests, the IT66121 chip sometimes misjudged whether it had an external screen, so, reference the it66121_user_guid.pdf about Audio/Video data is stable or not A typical initialization of HDMI link should be based on interrupt signal and appropriate register probing. Recommended flow is detailed in IT66121 Programming Guide. Simply put, the microcontroller should monitor the HPD status first. Upon valid HPD event, move on to check RxSENDetect register to see if the receiver chip is ready for further handshaking. When RxSENDetect is asserted, start reading EDID data through DDC channels and carry on the rest of the handshaking subsequently.If the micro-controller makes no use of the interrupt signal as well as the above-mentioned status registers, the link establishment might fail. Please do follow the suggested initialization flow recommended in IT66121 Programming Guide. So, I add the IT66121_SYS_STATUS_SENDECTECT register status detection. Signed-off-by: Yunlongli --- drivers/gpu/drm/bridge/ite-it66121.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/ite-it66121.c b/drivers/gpu/drm/bridge/ite-it66121.c index 2f2a09adb4bc..9ed4fa298d11 100644 --- a/drivers/gpu/drm/bridge/ite-it66121.c +++ b/drivers/gpu/drm/bridge/ite-it66121.c @@ -523,7 +523,7 @@ static bool it66121_is_hpd_detect(struct it66121_ctx *ctx) if (regmap_read(ctx->regmap, IT66121_SYS_STATUS_REG, &val)) return false; - return val & IT66121_SYS_STATUS_HPDETECT; + return ((val & IT66121_SYS_STATUS_HPDETECT) && (val & IT66121_SYS_STATUS_SENDECTECT)); } static int it66121_bridge_attach(struct drm_bridge *bridge, -- 2.20.1