From patchwork Mon Jan 18 11:35:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 366925 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, 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 CDBA5C4332E for ; Mon, 18 Jan 2021 11:50:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9AFB820829 for ; Mon, 18 Jan 2021 11:50:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390579AbhARLuZ (ORCPT ); Mon, 18 Jan 2021 06:50:25 -0500 Received: from mail.kernel.org ([198.145.29.99]:39324 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390931AbhARLqm (ORCPT ); Mon, 18 Jan 2021 06:46:42 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id B459D22D6E; Mon, 18 Jan 2021 11:46:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1610970385; bh=cUQqw0XAmxlACM9hTcvfPMhxA4zczWrIZ3fjAgsHN9I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=d0Y5DVDFQCmM0m3qb4IGyF1j02cI7kZANzrMGhKZa1lcQHVuHlozY8D2pb8Lit+vK OGd4bm4yqG7xnPzeiZvjAG1iw/dHUCGB9KBASek7p44xB4QQqXdTtN/LmVMq62fGAl MZZx01khUhYHDcxTT5tZUaixdbaF1dSL4E0MGknQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hans de Goede , =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= , Jani Nikula Subject: [PATCH 5.10 140/152] drm/i915/dsi: Use unconditional msleep for the panel_on_delay when there is no reset-deassert MIPI-sequence Date: Mon, 18 Jan 2021 12:35:15 +0100 Message-Id: <20210118113359.431863721@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210118113352.764293297@linuxfoundation.org> References: <20210118113352.764293297@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Hans de Goede commit 00cb645fd7e29bdd20967cd20fa8f77bcdf422f9 upstream. Commit 25b4620ee822 ("drm/i915/dsi: Skip delays for v3 VBTs in vid-mode") added an intel_dsi_msleep() helper which skips sleeping if the MIPI-sequences have a version of 3 or newer and the panel is in vid-mode; and it moved a bunch of msleep-s over to this new helper. This was based on my reading of the big comment around line 730 which starts with "Panel enable/disable sequences from the VBT spec.", where the "v3 video mode seq" column does not have any wait t# entries. Given that this code has been used on a lot of different devices without issues until now, it seems that my interpretation of the spec here is mostly correct. But now I have encountered one device, an Acer Aspire Switch 10 E SW3-016, where the panel will not light up unless we do actually honor the panel_on_delay after exexuting the MIPI_SEQ_PANEL_ON sequence. What seems to set this model apart is that it is lacking a MIPI_SEQ_DEASSERT_RESET sequence, which is where the power-on delay usually happens. Fix the panel not lighting up on this model by using an unconditional msleep(panel_on_delay) instead of intel_dsi_msleep() when there is no MIPI_SEQ_DEASSERT_RESET sequence. Fixes: 25b4620ee822 ("drm/i915/dsi: Skip delays for v3 VBTs in vid-mode") Signed-off-by: Hans de Goede Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20201118124058.26021-1-hdegoede@redhat.com (cherry picked from commit 6fdb335f1c9c0845b50625de1624d8445c4c4a07) Signed-off-by: Jani Nikula Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/display/vlv_dsi.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) --- a/drivers/gpu/drm/i915/display/vlv_dsi.c +++ b/drivers/gpu/drm/i915/display/vlv_dsi.c @@ -812,10 +812,20 @@ static void intel_dsi_pre_enable(struct intel_dsi_prepare(encoder, pipe_config); intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_POWER_ON); - intel_dsi_msleep(intel_dsi, intel_dsi->panel_on_delay); - /* Deassert reset */ - intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DEASSERT_RESET); + /* + * Give the panel time to power-on and then deassert its reset. + * Depending on the VBT MIPI sequences version the deassert-seq + * may contain the necessary delay, intel_dsi_msleep() will skip + * the delay in that case. If there is no deassert-seq, then an + * unconditional msleep is used to give the panel time to power-on. + */ + if (dev_priv->vbt.dsi.sequence[MIPI_SEQ_DEASSERT_RESET]) { + intel_dsi_msleep(intel_dsi, intel_dsi->panel_on_delay); + intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DEASSERT_RESET); + } else { + msleep(intel_dsi->panel_on_delay); + } if (IS_GEMINILAKE(dev_priv)) { glk_cold_boot = glk_dsi_enable_io(encoder);