From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A32C1126C01; Thu, 12 Dec 2024 08:18:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.15 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733991523; cv=none; b=E/buPLu6ICj/ZXJCGNWLVeUqPg+FUuEuo66aPJuZAj7FIlRCDfO1VjcGW98xicbs62r2FL4pQ5sPKcybclSZE1qdfkUVgraaIgTTW7UeQa9LwFhcjkSi/KEYzMnDXnrRKFys6adl/r9Hl1ij6E0YfKxC8Kt/wk7Oiaj4Jj+9x7o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733991523; c=relaxed/simple; bh=dVHHLoWyfFDn4SykayA6jpY7XugJsCld6W0h27L/1oo=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=O/GghdHBAsGmuAnUvH7FaGSPonZpNyNWl3WJNJwrifbENY7scj8pUROE0BUL9mFL9AqLvZzYXsxEHR0Xi3bnmDz2y3BmGLGfOP24RuN8QbwNT1iJuIFBnu/pVfV1AVkLRVu9ZtvcEB7TGGadsneMFFx3WzYFjYysJsT9txxhPcU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=ioJAYtTb; arc=none smtp.client-ip=198.175.65.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="ioJAYtTb" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1733991522; x=1765527522; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=dVHHLoWyfFDn4SykayA6jpY7XugJsCld6W0h27L/1oo=; b=ioJAYtTbNBFonlxPrUh0yGbFolMi4Z7osuz3yrhoWGoJ2SoaxqZ5BRiM kedP89Iwalsk/aV4KeZu1H08UcgJleo07WMkPGJqcg7qNBDD/KHHBsRQm a63OvafedMU4NTcgLd+f50h59Mm8byzAgWtGqPmu5+OhzOV6lFJOyYZO9 ZUd2lU30vm+MYICc3AFtWZwdxx7w7NlR5X2ZxnlPIsODymOdDzk3EwI7m 1qrKRQqrmjwg1M0aJDbpvIExrIfyKr8rVu0GbSOisBz2u+I0bhDbdJk88 ANGB7XqdV8pPlXSvKpYlBqZkcZVRoVcFrk1S+QmPxbtB1AocxVvRgGBuP w==; X-CSE-ConnectionGUID: HfQnmDw+R2eH/H8w2YIqrQ== X-CSE-MsgGUID: JCe5ne/6Samuom5oKi6FVA== X-IronPort-AV: E=McAfee;i="6700,10204,11283"; a="38086244" X-IronPort-AV: E=Sophos;i="6.12,227,1728975600"; d="scan'208";a="38086244" 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> Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain 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