From patchwork Thu Jul 9 12:04:27 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: sonika.jindal@intel.com X-Patchwork-Id: 6755371 Return-Path: X-Original-To: patchwork-intel-gfx@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id E0E1A9F2F0 for ; Thu, 9 Jul 2015 12:15:18 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id EA53420551 for ; Thu, 9 Jul 2015 12:15:16 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 68A7120567 for ; Thu, 9 Jul 2015 12:15:15 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8B6A36E2AB; Thu, 9 Jul 2015 05:15:14 -0700 (PDT) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by gabe.freedesktop.org (Postfix) with ESMTP id 1FFB16E4F8 for ; Thu, 9 Jul 2015 05:15:13 -0700 (PDT) Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga101.fm.intel.com with ESMTP; 09 Jul 2015 05:14:50 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.15,439,1432623600"; d="scan'208";a="759032095" Received: from sonikaji-desktop.iind.intel.com ([10.223.25.81]) by fmsmga002.fm.intel.com with ESMTP; 09 Jul 2015 05:14:48 -0700 From: Sonika Jindal To: intel-gfx@lists.freedesktop.org Date: Thu, 9 Jul 2015 17:34:27 +0530 Message-Id: <1436443470-28890-3-git-send-email-sonika.jindal@intel.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1436443470-28890-1-git-send-email-sonika.jindal@intel.com> References: <1436443470-28890-1-git-send-email-sonika.jindal@intel.com> Subject: [Intel-gfx] [PATCH 2/5] drm/i915: Add HDMI probe function X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Spam-Status: No, score=-4.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Shashank Sharma This patch adds a separate probe function for HDMI EDID read over DDC channel. This function has been registered as a .hot_plug handler for HDMI encoder. The reason behind addition of this separate function needs brief explaination. The current implementation of hdmi_detect() function re-sets the cached HDMI edid (in connector->detect_edid) in every detect call.This function gets called many times, sometimes directly from userspace probes, forcing drivers to read EDID every detect function call.This causes several problems like: 1. Race conditions in multiple hot_plug / unplug cases, between interrupts bottom halves and userspace detections. 2. Many Un-necessary EDID reads for single hotplug/unplug 3. HDMI complaince failures which expects only one EDID read per hotplug This function will be serving the purpose of really reading the EDID by really probing the DDC channel, and updating the cached EDID. The plan is to: 1. i915 IRQ handler bottom half function already calls intel_encoder->hotplug() function. Adding This probe function which will read the EDID only in case of a hotplug / unplug. 2. Reuse the cached EDID in hdmi_detect() function UNLESS we are forced to probe the EDID by the force=1 variable.The next patch in the series does this. 3. Make sure that we are using this force variable properly. Signed-off-by: Shashank Sharma --- drivers/gpu/drm/i915/intel_hdmi.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c index af4d1e6..064ddd8 100644 --- a/drivers/gpu/drm/i915/intel_hdmi.c +++ b/drivers/gpu/drm/i915/intel_hdmi.c @@ -1340,6 +1340,24 @@ intel_hdmi_set_edid(struct drm_connector *connector) return connected; } +void intel_hdmi_probe(struct intel_encoder *intel_encoder) +{ + struct intel_hdmi *intel_hdmi = + enc_to_intel_hdmi(&intel_encoder->base); + struct intel_connector *intel_connector = + intel_hdmi->attached_connector; + /* + * We are here, means there is a hotplug or a force + * detection. Clear the cached EDID and probe the + * DDC bus to check the current status of HDMI. + */ + intel_hdmi_unset_edid(&intel_connector->base); + if (intel_hdmi_set_edid(&intel_connector->base)) + DRM_DEBUG_DRIVER("DDC probe: got EDID\n"); + else + DRM_DEBUG_DRIVER("DDC probe: no EDID\n"); +} + static enum drm_connector_status intel_hdmi_detect(struct drm_connector *connector, bool force) { @@ -1997,6 +2015,7 @@ void intel_hdmi_init_connector(struct intel_digital_port *intel_dig_port, intel_connector->unregister = intel_connector_unregister; intel_hdmi_add_properties(intel_hdmi, connector); + intel_encoder->hot_plug = intel_hdmi_probe; intel_connector_attach_encoder(intel_connector, intel_encoder); drm_connector_register(connector);