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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 82087C433EF for ; Tue, 7 Jun 2022 21:22:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377795AbiFGVW1 (ORCPT ); Tue, 7 Jun 2022 17:22:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54540 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1380794AbiFGVQ7 (ORCPT ); Tue, 7 Jun 2022 17:16:59 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B179C2982C; Tue, 7 Jun 2022 11:57:25 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 6E76EB8233E; Tue, 7 Jun 2022 18:57:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D72C9C385A2; Tue, 7 Jun 2022 18:57:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654628243; bh=l+KNCHbgVMmd/yIZZbjqm8gJi4yhr1wcah02wTfDYYw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZNV031xN9tKDoklMlydq2Q2J6KlmDYQn9609QGRwJfsCEZqlwCJAGa9E+UN2k+GPQ 6yBSnWiPx2+0Ba58plVWGE9lEx9fvY3J3QbUWM5ghqbrFE3FZCubePZa1HTtm0nbRY 6oodKPSgSLi/Pb1hHSHk5zCYnjO24cj0cl8z1prU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tom Rix , Robert Foss , Sasha Levin Subject: [PATCH 5.18 258/879] drm/bridge: anx7625: check the return on anx7625_aux_trans Date: Tue, 7 Jun 2022 18:56:16 +0200 Message-Id: <20220607165010.338124319@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220607165002.659942637@linuxfoundation.org> References: <20220607165002.659942637@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Tom Rix [ Upstream commit d583e752732421b26fef0d65020565f3bef12248 ] Clang static analysis reports this issue anx7625.c:876:13: warning: The left operand of '&' is a garbage value if (!(bcap & 0xOA01)) { ~~~~ ^ bcap is only set by a successful call to anx7625_aux_trans(). So check. Fixes: cd1637c7e480 ("drm/bridge: anx7625: add HDCP support") Signed-off-by: Tom Rix Fixes: adca62ec370c ("drm/bridge: anx7625: Support reading edid through aux channel") Signed-off-by: Robert Foss Link: https://patchwork.freedesktop.org/patch/msgid/20220303201943.501746-1-trix@redhat.com Reviewed-by: Robert Foss Signed-off-by: Sasha Levin --- drivers/gpu/drm/bridge/analogix/anx7625.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c index 31ecf5626f1d..8e1851a57638 100644 --- a/drivers/gpu/drm/bridge/analogix/anx7625.c +++ b/drivers/gpu/drm/bridge/analogix/anx7625.c @@ -874,7 +874,10 @@ static int anx7625_hdcp_enable(struct anx7625_data *ctx) } /* Read downstream capability */ - anx7625_aux_trans(ctx, DP_AUX_NATIVE_READ, 0x68028, 1, &bcap); + ret = anx7625_aux_trans(ctx, DP_AUX_NATIVE_READ, 0x68028, 1, &bcap); + if (ret < 0) + return ret; + if (!(bcap & 0x01)) { pr_warn("downstream not support HDCP 1.4, cap(%x).\n", bcap); return 0; -- 2.35.1