From patchwork Thu Mar 31 18:45:00 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jani Nikula X-Patchwork-Id: 12797580 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 65F12C433EF for ; Thu, 31 Mar 2022 18:45:42 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1158610F46C; Thu, 31 Mar 2022 18:45:41 +0000 (UTC) Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by gabe.freedesktop.org (Postfix) with ESMTPS id 63E5310F46A; Thu, 31 Mar 2022 18:45:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1648752338; x=1680288338; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=UmsDR08Qio5SdDt08gcg9htocecF05aXi2TcpSL5194=; b=PWIDF5jofq+W8g+I+CbOG9lboDmbZwNSqhmqK0Tj//EeRNA0KOmynz7J G8z/7QYyxI9ABcTP9ECwSaFtiWc2hllMrzfz2Vm7J5J6suID9brKbxtUW 5WgwWr6w3o0vdc6KdZYNizTtD1Q8Xy7NJ1wCBlwT2a++o6NCoRFfieyhU NZHgNV5hxDysdrSfOaOxh3+mTlBLbtk8ZGQUPgdf3ukDC45HU+D6q79Il jH+rmSVQ5k9E7A51jh+sognM0kzfEl9Sq+uiE1/TcPNpKrcAnq8qe+x8j +9pyBKmrzz1QwI+yeirdPeQ5dMiReG9zzvBK9DJrMWU2oUqHdmmyQmKXw w==; X-IronPort-AV: E=McAfee;i="6200,9189,10302"; a="323099369" X-IronPort-AV: E=Sophos;i="5.90,225,1643702400"; d="scan'208";a="323099369" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Mar 2022 11:45:27 -0700 X-IronPort-AV: E=Sophos;i="5.90,225,1643702400"; d="scan'208";a="522460055" Received: from gluca-mobl1.ger.corp.intel.com (HELO localhost) ([10.252.48.194]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Mar 2022 11:45:26 -0700 From: Jani Nikula To: dri-devel@lists.freedesktop.org Subject: [PATCH v2 03/12] drm/edid: add edid_block_tag() helper to get the EDID extension tag Date: Thu, 31 Mar 2022 21:45:00 +0300 Message-Id: <3f27c67db63c186a48e83fdee2d1ac8a17714e78.1648752228.git.jani.nikula@intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: References: MIME-Version: 1.0 Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo 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: jani.nikula@intel.com, intel-gfx@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The extension tag at offset 0 is not present in struct edid, add a helper for it to reduce the need to use u8 *. Cc: Ville Syrjälä Signed-off-by: Jani Nikula Reviewed-by: Ville Syrjälä --- drivers/gpu/drm/drm_edid.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 82e00650af14..7c9ce5b0bd5b 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -1618,6 +1618,13 @@ static int edid_block_get_checksum(const void *_block) return block->checksum; } +static int edid_block_tag(const void *_block) +{ + const u8 *block = _block; + + return block[0]; +} + static bool drm_edid_is_zero(const u8 *in_edid, int length) { if (memchr_inv(in_edid, 0, length)) @@ -1710,7 +1717,7 @@ bool drm_edid_block_valid(u8 *raw_edid, int block, bool print_bad_edid, *edid_corrupt = true; /* allow CEA to slide through, switches mangle this */ - if (raw_edid[0] == CEA_EXT) { + if (edid_block_tag(raw_edid) == CEA_EXT) { DRM_DEBUG("EDID checksum is invalid, remainder is %d\n", csum); DRM_DEBUG("Assuming a KVM switch modified the CEA block but left the original checksum\n"); } else { @@ -1722,7 +1729,7 @@ bool drm_edid_block_valid(u8 *raw_edid, int block, bool print_bad_edid, } /* per-block-type checks */ - switch (raw_edid[0]) { + switch (edid_block_tag(raw_edid)) { case 0: /* base */ if (edid->version != 1) { DRM_NOTE("EDID has major version %d, instead of 1\n", edid->version); @@ -3366,7 +3373,7 @@ const u8 *drm_find_edid_extension(const struct edid *edid, /* Find CEA extension */ for (i = *ext_index; i < edid->extensions; i++) { edid_ext = (const u8 *)edid + EDID_LENGTH * (i + 1); - if (edid_ext[0] == ext_id) + if (edid_block_tag(edid_ext) == ext_id) break; }