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 09133CA5FB1 for ; Wed, 30 Sep 2026 08:04:56 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 91C6A10F230; Wed, 30 Sep 2026 08:04:55 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="JbjJdxQV"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.10]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4D0BE10F229; Wed, 30 Sep 2026 08:04:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1790755495; x=1822291495; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version:content-transfer-encoding; bh=aB8Cp4nhgf7pMdLW6i8ghQb1w1f/0/D8MNkDliazAv4=; b=JbjJdxQVlZ7af4VExL1DDfkhiTkrzmiYpL9eXfd0aDaYsp537+TKZk6T JreZSn6MqlYgPcjxU6Or7PFTU0GlXH51cVGsqAhdJ2xgUghK+4FwZ8x1s 8tgAphk0nr494vNh37JGoLLpa7b10T59gILa+aUuLkKt6sZ5eflnujLzk 2qVHm8kp/R+e1aLz2fDcSVa3DV2vGc/hAbvWm790VI4NTOH8EEfXZP/bW R2WCgBdprgSLv2xHQA5ovtpI+79sNcXjCSbFLzwrzcoauUZ25y8vVitOX Ph3QFrlAwXUHD0KahCrYjtXHyynSkcHouiEz3FnbT4+IRm2GgiZL3unn2 Q==; X-CSE-ConnectionGUID: BAgFCt9gQJ6Kg1QN/IDbxw== X-CSE-MsgGUID: xnjgwFPCS8eLKXPYYBwyXQ== X-IronPort-AV: E=McAfee;i="6800,10657,11920"; a="107873331" X-IronPort-AV: E=Sophos;i="6.27,132,1787036400"; d="scan'208";a="107873331" Received: from fmviesa008.fm.intel.com ([10.60.135.148]) by orvoesa102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Sep 2026 01:04:54 -0700 X-CSE-ConnectionGUID: Cu/v+AVgQF+x1mViGCxdEQ== X-CSE-MsgGUID: dg7Wz5AVSvSpELsP3mYYzg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,132,1787036400"; d="scan'208";a="275761811" Received: from pgcooper-mobl3.ger.corp.intel.com (HELO localhost) ([10.245.245.107]) by fmviesa008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Sep 2026 01:04:51 -0700 From: Jani Nikula To: Animesh Manna , intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, dri-devel@lists.freedesktop.org Cc: jouni.hogander@intel.com, suraj.kandpal@intel.com, Animesh Manna Subject: Re: [PATCH v6 02/18] drm/i915/alpm: Move alpm sink capability readout into a separate function In-Reply-To: <20260915180449.277933-3-animesh.manna@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs Bertel Jungin Aukio 5, 02600 Espoo, Finland References: <20260915180449.277933-1-animesh.manna@intel.com> <20260915180449.277933-3-animesh.manna@intel.com> Date: Wed, 30 Sep 2026 11:04:49 +0300 Message-ID: <2ed6b4ccefd2d302433fb990401b0d62efa75c84@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Tue, 15 Sep 2026, Animesh Manna wrote: > Abstract ALPM DPCD initialization into its own function. > > v2: > - Improve commit description. [Suraj, Jouni] > > Cc: Jouni H=C3=B6gander > Signed-off-by: Animesh Manna > --- > drivers/gpu/drm/i915/display/intel_alpm.c | 11 +++++++++++ > drivers/gpu/drm/i915/display/intel_alpm.h | 1 + > drivers/gpu/drm/i915/display/intel_dp.c | 6 +----- > 3 files changed, 13 insertions(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c b/drivers/gpu/drm/= i915/display/intel_alpm.c > index 10943539bc7c..a6743fe62d48 100644 > --- a/drivers/gpu/drm/i915/display/intel_alpm.c > +++ b/drivers/gpu/drm/i915/display/intel_alpm.c > @@ -43,6 +43,17 @@ bool intel_alpm_is_alpm_aux_less(struct intel_dp *inte= l_dp, > (crtc_state->has_lobf && intel_alpm_aux_less_wake_supported(intel_dp)); > } >=20=20 > +bool intel_alpm_init_dpcd(struct intel_dp *intel_dp) > +{ > + u8 dpcd; > + > + if (drm_dp_dpcd_read_byte(&intel_dp->aux, DP_RECEIVER_ALPM_CAP, &dpcd) = < 0) > + return false; > + > + intel_dp->alpm_dpcd =3D dpcd; > + return true; > +} Why not propagate the original error instead of flattening to a boolean? What does boolean true/false mean for a function that's not a predicate function but "init"? >From a maintenance perspective, the mixing of bool vs. int return values is a problem because you never know what is being checked for in the caller side: if (!intel_alpm_init_dpcd()) Does that return bool and false means failure? Or does that return int and false means success?! BR, Jani. > + > void intel_alpm_init(struct intel_dp *intel_dp) > { > mutex_init(&intel_dp->alpm.lock); > diff --git a/drivers/gpu/drm/i915/display/intel_alpm.h b/drivers/gpu/drm/= i915/display/intel_alpm.h > index f8f605d94f96..56c3e1482e37 100644 > --- a/drivers/gpu/drm/i915/display/intel_alpm.h > +++ b/drivers/gpu/drm/i915/display/intel_alpm.h > @@ -15,6 +15,7 @@ struct intel_connector; > struct intel_atomic_state; > struct intel_crtc; >=20=20 > +bool intel_alpm_init_dpcd(struct intel_dp *intel_dp); > void intel_alpm_init(struct intel_dp *intel_dp); > bool intel_alpm_compute_params(struct intel_dp *intel_dp, > struct intel_crtc_state *crtc_state); > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i9= 15/display/intel_dp.c > index 0cd5e6b5034c..650c8b39270b 100644 > --- a/drivers/gpu/drm/i915/display/intel_dp.c > +++ b/drivers/gpu/drm/i915/display/intel_dp.c > @@ -4783,7 +4783,6 @@ static bool > intel_edp_init_dpcd(struct intel_dp *intel_dp, struct intel_connector *c= onnector) > { > struct intel_display *display =3D to_intel_display(intel_dp); > - int ret; > u8 dprx; >=20=20 > /* this function is meant to be called only once */ > @@ -4829,10 +4828,7 @@ intel_edp_init_dpcd(struct intel_dp *intel_dp, str= uct intel_connector *connector > */ > intel_dp_init_source_oui(intel_dp); >=20=20 > - /* Read the ALPM DPCD caps */ > - ret =3D drm_dp_dpcd_read_byte(&intel_dp->aux, DP_RECEIVER_ALPM_CAP, > - &intel_dp->alpm_dpcd); > - if (ret < 0) > + if (!intel_alpm_init_dpcd(intel_dp)) > return false; >=20=20 > /* --=20 Jani Nikula, Intel