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 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 A1D58E7717F for ; Thu, 12 Dec 2024 08:18:42 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4241310E20A; Thu, 12 Dec 2024 08:18:42 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="N/QLTTsZ"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.15]) by gabe.freedesktop.org (Postfix) with ESMTPS id 39E5F10E20A; Thu, 12 Dec 2024 08:18:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1733991521; x=1765527521; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=dVHHLoWyfFDn4SykayA6jpY7XugJsCld6W0h27L/1oo=; b=N/QLTTsZ5sPUx3LVxIO4pLi5GS1T0ZyV9b9QThbJZvExwsLGtPQuYLNG N3nAeRBDZoHN5tWJnStvzToGV1uhGCPExQB04wg/VGYyHykkwoTnWh2qN yVQ/dcuSchgIfRnza9hGEwsS2Vua5j79yOerul/avUcIu3Fi/6yPZ1mWg lKyEiHR/48BvSE0dUEjdbZOoeiISH+JMKGzNEsZ+BJFzevuq0xvmPa/Wf XWKmEHuzKw3p1IkAcK4Mq4eB8jIl+UxBe1emO3YmquH+XHtlHLE5hE16u XfOQ96O+ewdk3CSafOpY6IRdLLVhg7JhMjp5j9ss7JWUQZQKi+I7+9U6X g==; X-CSE-ConnectionGUID: pJ6q5DxpTtaSXM7CeVeNuQ== X-CSE-MsgGUID: LPZ8zC+gTFGYKfoAl44vbw== X-IronPort-AV: E=McAfee;i="6700,10204,11283"; a="38086245" X-IronPort-AV: E=Sophos;i="6.12,227,1728975600"; d="scan'208";a="38086245" Received: from fmviesa008.fm.intel.com ([10.60.135.148]) by orvoesa107.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Dec 2024 00:18:41 -0800 X-CSE-ConnectionGUID: AIQA0pf8S+KINcKZiVC2wA== X-CSE-MsgGUID: 5JT1BapkSSCqRnj0Cwzaiw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.12,227,1728975600"; d="scan'208";a="96397015" Received: from klitkey1-mobl1.ger.corp.intel.com (HELO localhost) ([10.245.246.101]) by fmviesa008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Dec 2024 00:18:33 -0800 From: Jani Nikula To: Dmitry Baryshkov , Johan Hovold Cc: Abel Vesa , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Karol Herbst , Lyude Paul , Danilo Krummrich , Rodrigo Vivi , Joonas Lahtinen , Tvrtko Ursulin , Rob Clark , Abhinav Kumar , Sean Paul , Marijn Suijten , Bjorn Andersson , Konrad Dybcio , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, nouveau@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org Subject: Re: [PATCH v2 1/4] drm/dp: Add helper to set LTTPRs in transparent mode In-Reply-To: <3omcjrgfkdmw466ok7gej2jge25vtwzaiycwz2xgejwppyvkza@rhssgk7xz4hj> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20241211-drm-dp-msm-add-lttpr-transparent-mode-set-v2-0-d5906ed38b28@linaro.org> <20241211-drm-dp-msm-add-lttpr-transparent-mode-set-v2-1-d5906ed38b28@linaro.org> <3omcjrgfkdmw466ok7gej2jge25vtwzaiycwz2xgejwppyvkza@rhssgk7xz4hj> Date: Thu, 12 Dec 2024 10:18:30 +0200 Message-ID: <87pllxxqjt.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" On Wed, 11 Dec 2024, Dmitry Baryshkov wrote: > On Wed, Dec 11, 2024 at 03:42:27PM +0100, Johan Hovold wrote: >> On Wed, Dec 11, 2024 at 03:04:12PM +0200, Abel Vesa wrote: >> >> > +/** >> > + * drm_dp_lttpr_set_transparent_mode - set the LTTPR in transparent mode >> > + * @aux: DisplayPort AUX channel >> > + * @enable: Enable or disable transparent mode >> > + * >> > + * Returns 0 on success or a negative error code on failure. >> > + */ >> > +int drm_dp_lttpr_set_transparent_mode(struct drm_dp_aux *aux, bool enable) >> > +{ >> > + u8 val = enable ? DP_PHY_REPEATER_MODE_TRANSPARENT : >> > + DP_PHY_REPEATER_MODE_NON_TRANSPARENT; >> > + int ret = drm_dp_dpcd_writeb(aux, DP_PHY_REPEATER_MODE, val); >> > + >> > + return ret == 1 ? 0 : ret; >> >> This looks correct, but I had to go look at drm_dp_dpcd_writeb() to make >> sure it never returns 0 (for short transfers). >> >> > +} >> > +EXPORT_SYMBOL(drm_dp_lttpr_set_transparent_mode); >> >> This appears to be what the driver currently uses, but why not >> EXPORT_SYMBOL_GPL? > > $ git grep EXPORT_SYMBOL drivers/gpu/drm/*.c | wc -l > 962 > $ git grep EXPORT_SYMBOL_GPL drivers/gpu/drm/*.c | wc -l > 93 It's even more tilted under display/. BR, Jani. -- Jani Nikula, Intel