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 X-Spam-Level: X-Spam-Status: No, score=-16.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 34651C433DB for ; Mon, 8 Feb 2021 23:42:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 107E364E9A for ; Mon, 8 Feb 2021 23:42:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231653AbhBHXmb (ORCPT ); Mon, 8 Feb 2021 18:42:31 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:20575 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231503AbhBHXlB (ORCPT ); Mon, 8 Feb 2021 18:41:01 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612827575; 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=z7QuXw0xqGJm2yN8W3IbIyrys9hJs+25FapVqIcdCi8=; b=DYevw5xKkpEEUo0Wq9nkNq/kpAQzhSnUxCNcthLZMyNyWf6kEh7gLDu6puemzWGcQNTUoc JzEkW8ybC8jQ65xh5MsTBsg8XsIf5mmkWRqXzJElA1wB0ok5eGp06TPZIg4tERQfu32YDH mcMG48dPUgAz3GsI0TpbEuBw1waKdcQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-326-JNOM0HblN0CWnUFq04JA1g-1; Mon, 08 Feb 2021 18:39:32 -0500 X-MC-Unique: JNOM0HblN0CWnUFq04JA1g-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7A280804023; Mon, 8 Feb 2021 23:39:30 +0000 (UTC) Received: from Whitewolf.redhat.com (ovpn-114-219.rdu2.redhat.com [10.10.114.219]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6EE3260938; Mon, 8 Feb 2021 23:39:29 +0000 (UTC) From: Lyude Paul To: dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Cc: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , David Airlie , Daniel Vetter , Sean Paul , linux-kernel@vger.kernel.org (open list) Subject: [RFC v4 08/11] drm/i915/dpcd_bl: Return early in vesa_calc_max_backlight if we can't read PWMGEN_BIT_COUNT Date: Mon, 8 Feb 2021 18:38:58 -0500 Message-Id: <20210208233902.1289693-9-lyude@redhat.com> In-Reply-To: <20210208233902.1289693-1-lyude@redhat.com> References: <20210208233902.1289693-1-lyude@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If we can't read DP_EDP_PWMGEN_BIT_COUNT in intel_dp_aux_vesa_calc_max_backlight() but do have a valid PWM frequency defined in the VBT, we'll keep going in the function until we inevitably fail on reading DP_EDP_PWMGEN_BIT_COUNT_CAP_MIN. There's not much point in doing this, so just return early. Signed-off-by: Lyude Paul --- drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c index 611eb3a7cc08..a139f0e08839 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c @@ -449,11 +449,14 @@ static u32 intel_dp_aux_vesa_calc_max_backlight(struct intel_connector *connecto int freq, fxp, fxp_min, fxp_max, fxp_actual, f = 1; u8 pn, pn_min, pn_max; - if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, &pn) == 1) { - pn &= DP_EDP_PWMGEN_BIT_COUNT_MASK; - max_backlight = (1 << pn) - 1; + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, &pn) != 1) { + drm_dbg_kms(&i915->drm, "Failed to read pwmgen bit count cap\n"); + return 0; } + pn &= DP_EDP_PWMGEN_BIT_COUNT_MASK; + max_backlight = (1 << pn) - 1; + /* Find desired value of (F x P) * Note that, if F x P is out of supported range, the maximum value or * minimum value will applied automatically. So no need to check that. -- 2.29.2 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 X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 EED4FC433E0 for ; Mon, 8 Feb 2021 23:39:41 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id AF6D864E77 for ; Mon, 8 Feb 2021 23:39:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AF6D864E77 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=nouveau-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4C9896EA45; Mon, 8 Feb 2021 23:39:37 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id 76CA36EA3E for ; Mon, 8 Feb 2021 23:39:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612827573; 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=z7QuXw0xqGJm2yN8W3IbIyrys9hJs+25FapVqIcdCi8=; b=ToM2XLMalE174IxlNxEfuuj5xS72M3kiYSdrA+kl9joWFUQ/VfXSdLBjWeTms9jKAwALlT porY830O+uzrkdmWudDZG9uwNpF0vrMTAd0DTSg9OxFKOHn/dMscGEW7d8isVybEWS7891 dm1yHbKfaJ+qoTmPsj7HdZnlOpWXL4k= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-326-JNOM0HblN0CWnUFq04JA1g-1; Mon, 08 Feb 2021 18:39:32 -0500 X-MC-Unique: JNOM0HblN0CWnUFq04JA1g-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7A280804023; Mon, 8 Feb 2021 23:39:30 +0000 (UTC) Received: from Whitewolf.redhat.com (ovpn-114-219.rdu2.redhat.com [10.10.114.219]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6EE3260938; Mon, 8 Feb 2021 23:39:29 +0000 (UTC) From: Lyude Paul To: dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Date: Mon, 8 Feb 2021 18:38:58 -0500 Message-Id: <20210208233902.1289693-9-lyude@redhat.com> In-Reply-To: <20210208233902.1289693-1-lyude@redhat.com> References: <20210208233902.1289693-1-lyude@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Nouveau] [RFC v4 08/11] drm/i915/dpcd_bl: Return early in vesa_calc_max_backlight if we can't read PWMGEN_BIT_COUNT X-BeenThere: nouveau@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Nouveau development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: David Airlie , Joonas Lahtinen , open list , Jani Nikula , Sean Paul , Daniel Vetter , Rodrigo Vivi Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: nouveau-bounces@lists.freedesktop.org Sender: "Nouveau" If we can't read DP_EDP_PWMGEN_BIT_COUNT in intel_dp_aux_vesa_calc_max_backlight() but do have a valid PWM frequency defined in the VBT, we'll keep going in the function until we inevitably fail on reading DP_EDP_PWMGEN_BIT_COUNT_CAP_MIN. There's not much point in doing this, so just return early. Signed-off-by: Lyude Paul --- drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c index 611eb3a7cc08..a139f0e08839 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c @@ -449,11 +449,14 @@ static u32 intel_dp_aux_vesa_calc_max_backlight(struct intel_connector *connecto int freq, fxp, fxp_min, fxp_max, fxp_actual, f = 1; u8 pn, pn_min, pn_max; - if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, &pn) == 1) { - pn &= DP_EDP_PWMGEN_BIT_COUNT_MASK; - max_backlight = (1 << pn) - 1; + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, &pn) != 1) { + drm_dbg_kms(&i915->drm, "Failed to read pwmgen bit count cap\n"); + return 0; } + pn &= DP_EDP_PWMGEN_BIT_COUNT_MASK; + max_backlight = (1 << pn) - 1; + /* Find desired value of (F x P) * Note that, if F x P is out of supported range, the maximum value or * minimum value will applied automatically. So no need to check that. -- 2.29.2 _______________________________________________ Nouveau mailing list Nouveau@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/nouveau 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 X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 C5E94C433E6 for ; Mon, 8 Feb 2021 23:39:44 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 8F30964E7B for ; Mon, 8 Feb 2021 23:39:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8F30964E7B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D838D6EA4A; Mon, 8 Feb 2021 23:39:37 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9EA896EA42 for ; Mon, 8 Feb 2021 23:39:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612827573; 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=z7QuXw0xqGJm2yN8W3IbIyrys9hJs+25FapVqIcdCi8=; b=ToM2XLMalE174IxlNxEfuuj5xS72M3kiYSdrA+kl9joWFUQ/VfXSdLBjWeTms9jKAwALlT porY830O+uzrkdmWudDZG9uwNpF0vrMTAd0DTSg9OxFKOHn/dMscGEW7d8isVybEWS7891 dm1yHbKfaJ+qoTmPsj7HdZnlOpWXL4k= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-326-JNOM0HblN0CWnUFq04JA1g-1; Mon, 08 Feb 2021 18:39:32 -0500 X-MC-Unique: JNOM0HblN0CWnUFq04JA1g-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7A280804023; Mon, 8 Feb 2021 23:39:30 +0000 (UTC) Received: from Whitewolf.redhat.com (ovpn-114-219.rdu2.redhat.com [10.10.114.219]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6EE3260938; Mon, 8 Feb 2021 23:39:29 +0000 (UTC) From: Lyude Paul To: dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Subject: [RFC v4 08/11] drm/i915/dpcd_bl: Return early in vesa_calc_max_backlight if we can't read PWMGEN_BIT_COUNT Date: Mon, 8 Feb 2021 18:38:58 -0500 Message-Id: <20210208233902.1289693-9-lyude@redhat.com> In-Reply-To: <20210208233902.1289693-1-lyude@redhat.com> References: <20210208233902.1289693-1-lyude@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 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: , Cc: David Airlie , open list , Sean Paul , Rodrigo Vivi Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" If we can't read DP_EDP_PWMGEN_BIT_COUNT in intel_dp_aux_vesa_calc_max_backlight() but do have a valid PWM frequency defined in the VBT, we'll keep going in the function until we inevitably fail on reading DP_EDP_PWMGEN_BIT_COUNT_CAP_MIN. There's not much point in doing this, so just return early. Signed-off-by: Lyude Paul --- drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c index 611eb3a7cc08..a139f0e08839 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c @@ -449,11 +449,14 @@ static u32 intel_dp_aux_vesa_calc_max_backlight(struct intel_connector *connecto int freq, fxp, fxp_min, fxp_max, fxp_actual, f = 1; u8 pn, pn_min, pn_max; - if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, &pn) == 1) { - pn &= DP_EDP_PWMGEN_BIT_COUNT_MASK; - max_backlight = (1 << pn) - 1; + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, &pn) != 1) { + drm_dbg_kms(&i915->drm, "Failed to read pwmgen bit count cap\n"); + return 0; } + pn &= DP_EDP_PWMGEN_BIT_COUNT_MASK; + max_backlight = (1 << pn) - 1; + /* Find desired value of (F x P) * Note that, if F x P is out of supported range, the maximum value or * minimum value will applied automatically. So no need to check that. -- 2.29.2 _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel 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 X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 44BC3C433E0 for ; Mon, 8 Feb 2021 23:39:44 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 0810C64E7B for ; Mon, 8 Feb 2021 23:39:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0810C64E7B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 91CE56EA53; Mon, 8 Feb 2021 23:39:38 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id AAC7D6EA4A for ; Mon, 8 Feb 2021 23:39:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612827575; 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=z7QuXw0xqGJm2yN8W3IbIyrys9hJs+25FapVqIcdCi8=; b=DYevw5xKkpEEUo0Wq9nkNq/kpAQzhSnUxCNcthLZMyNyWf6kEh7gLDu6puemzWGcQNTUoc JzEkW8ybC8jQ65xh5MsTBsg8XsIf5mmkWRqXzJElA1wB0ok5eGp06TPZIg4tERQfu32YDH mcMG48dPUgAz3GsI0TpbEuBw1waKdcQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-326-JNOM0HblN0CWnUFq04JA1g-1; Mon, 08 Feb 2021 18:39:32 -0500 X-MC-Unique: JNOM0HblN0CWnUFq04JA1g-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7A280804023; Mon, 8 Feb 2021 23:39:30 +0000 (UTC) Received: from Whitewolf.redhat.com (ovpn-114-219.rdu2.redhat.com [10.10.114.219]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6EE3260938; Mon, 8 Feb 2021 23:39:29 +0000 (UTC) From: Lyude Paul To: dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Date: Mon, 8 Feb 2021 18:38:58 -0500 Message-Id: <20210208233902.1289693-9-lyude@redhat.com> In-Reply-To: <20210208233902.1289693-1-lyude@redhat.com> References: <20210208233902.1289693-1-lyude@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Subject: [Intel-gfx] [RFC v4 08/11] drm/i915/dpcd_bl: Return early in vesa_calc_max_backlight if we can't read PWMGEN_BIT_COUNT 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: , Cc: David Airlie , open list , Sean Paul Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" If we can't read DP_EDP_PWMGEN_BIT_COUNT in intel_dp_aux_vesa_calc_max_backlight() but do have a valid PWM frequency defined in the VBT, we'll keep going in the function until we inevitably fail on reading DP_EDP_PWMGEN_BIT_COUNT_CAP_MIN. There's not much point in doing this, so just return early. Signed-off-by: Lyude Paul --- drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c index 611eb3a7cc08..a139f0e08839 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c @@ -449,11 +449,14 @@ static u32 intel_dp_aux_vesa_calc_max_backlight(struct intel_connector *connecto int freq, fxp, fxp_min, fxp_max, fxp_actual, f = 1; u8 pn, pn_min, pn_max; - if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, &pn) == 1) { - pn &= DP_EDP_PWMGEN_BIT_COUNT_MASK; - max_backlight = (1 << pn) - 1; + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_PWMGEN_BIT_COUNT, &pn) != 1) { + drm_dbg_kms(&i915->drm, "Failed to read pwmgen bit count cap\n"); + return 0; } + pn &= DP_EDP_PWMGEN_BIT_COUNT_MASK; + max_backlight = (1 << pn) - 1; + /* Find desired value of (F x P) * Note that, if F x P is out of supported range, the maximum value or * minimum value will applied automatically. So no need to check that. -- 2.29.2 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx