From patchwork Sat Jan 11 19:27:29 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aradhya Bhatia X-Patchwork-Id: 13936155 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 91549E7719C for ; Sat, 11 Jan 2025 19:28:05 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 170F410E218; Sat, 11 Jan 2025 19:28:05 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=linux.dev header.i=@linux.dev header.b="VTIqkDQX"; dkim-atps=neutral Received: from out-186.mta1.migadu.com (out-186.mta1.migadu.com [95.215.58.186]) by gabe.freedesktop.org (Postfix) with ESMTPS id F3BEB10E218 for ; Sat, 11 Jan 2025 19:28:02 +0000 (UTC) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1736623681; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=NRAlMFaOYUM3PL1/bODAdBoL/WvDYph2ZNsIdv2WJ+o=; b=VTIqkDQXmb1Td6f6HNj7KdUgblP704E06RTsdmpr568SQZiOctBy6sRFL/uNMeEsFzosL+ qR+4euTvMfk4MsYwbFC3UNoUTW/5brCvn8fiwcO1HWOpJpNU9dq7Ny3jXO6bybpYyn29ah ZvAnHrYH333bNc6a1ayXxdK5yarlGIk= From: Aradhya Bhatia To: Tomi Valkeinen , Dmitry Baryshkov , Laurent Pinchart , Andrzej Hajda , Neil Armstrong , Robert Foss , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter Cc: Nishanth Menon , Vignesh Raghavendra , Devarsh Thakkar , Praneeth Bajjuri , Udit Kumar , Jayesh Choudhary , DRI Development List , Linux Kernel List , Aradhya Bhatia Subject: [PATCH v6 03/12] drm/bridge: cdns-dsi: Fix phy de-init and flag it so Date: Sun, 12 Jan 2025 00:57:29 +0530 Message-Id: <20250111192738.308889-4-aradhya.bhatia@linux.dev> In-Reply-To: <20250111192738.308889-1-aradhya.bhatia@linux.dev> References: <20250111192738.308889-1-aradhya.bhatia@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT 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" From: Aradhya Bhatia The driver code doesn't have a de-initialization path as yet, and so it does not clear the phy_initialized flag while suspending. This is a problem because after resume the driver looks at this flag to determine if a Phy re-initialization is required or not. It is in fact required because the hardware is resuming from a suspend, but the driver does not carry out any re-initialization causing the D-Phy to not work at all. Add the counterpart of phy_power_on(), that is phy_power_off() from the _bridge_disable() and clear the flags so that the Phy can be initialized again when required. Move the Phy initialization from _bridge_enable() to _resume(), and de-initialize during the _suspend() - so that the phy_{init, exit}() take place once every resume/suspend cycle. The order of calls still remains the same. phy_init() needs to be called before phy_power_on() - which happens still. What this patch changes is the frequency of the phy_init() call. Instead of it being called once every bridge enable/disable cycle, it is now being called once every resume/suspend cycle. This move has been considered safe after numerous tests with the hardware. Fixes: fced5a364dee ("drm/bridge: cdns: Convert to phy framework") Signed-off-by: Aradhya Bhatia Signed-off-by: Aradhya Bhatia --- drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c index 056583e81155..47550891427c 100644 --- a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c +++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c @@ -672,6 +672,10 @@ static void cdns_dsi_bridge_disable(struct drm_bridge *bridge) if (dsi->platform_ops && dsi->platform_ops->disable) dsi->platform_ops->disable(dsi); + phy_power_off(dsi->dphy); + dsi->link_initialized = false; + dsi->phy_initialized = false; + pm_runtime_put(dsi->base.dev); } @@ -698,7 +702,6 @@ static void cdns_dsi_hs_init(struct cdns_dsi *dsi) DPHY_CMN_PDN | DPHY_PLL_PDN, dsi->regs + MCTL_DPHY_CFG0); - phy_init(dsi->dphy); phy_set_mode(dsi->dphy, PHY_MODE_MIPI_DPHY); phy_configure(dsi->dphy, &output->phy_opts); phy_power_on(dsi->dphy); @@ -1120,6 +1123,8 @@ static int __maybe_unused cdns_dsi_resume(struct device *dev) clk_prepare_enable(dsi->dsi_p_clk); clk_prepare_enable(dsi->dsi_sys_clk); + phy_init(dsi->dphy); + return 0; } @@ -1127,10 +1132,11 @@ static int __maybe_unused cdns_dsi_suspend(struct device *dev) { struct cdns_dsi *dsi = dev_get_drvdata(dev); + phy_exit(dsi->dphy); + clk_disable_unprepare(dsi->dsi_sys_clk); clk_disable_unprepare(dsi->dsi_p_clk); reset_control_assert(dsi->dsi_p_rst); - dsi->link_initialized = false; return 0; }