From patchwork Wed Mar 24 08:53:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Hans Verkuil X-Patchwork-Id: 12160537 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=-17.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 A017EC433DB for ; Wed, 24 Mar 2021 08:54:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6E1ED619F7 for ; Wed, 24 Mar 2021 08:54:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233715AbhCXIyE (ORCPT ); Wed, 24 Mar 2021 04:54:04 -0400 Received: from lb1-smtp-cloud8.xs4all.net ([194.109.24.21]:37171 "EHLO lb1-smtp-cloud8.xs4all.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234045AbhCXIxj (ORCPT ); Wed, 24 Mar 2021 04:53:39 -0400 Received: from cust-b5b5937f ([IPv6:fc0c:c16d:66b8:757f:c639:739b:9d66:799d]) by smtp-cloud8.xs4all.net with ESMTPA id OzGelwIG0CAEGOzGhlZ4uS; Wed, 24 Mar 2021 09:53:38 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=xs4all.nl; s=s2; t=1616576018; bh=yUW/RaeQJPREro1UhJl7zUUe5GW6I7n4sN+UfTklbiA=; h=To:From:Subject:Message-ID:Date:MIME-Version:Content-Type:From: Subject; b=t7mS48/If8c2VqZG3sdGugENOzCZVV+x8kySCc6gu5VNEdk5xlh8cmhWSmOTfneSU jbxRogAbefyflOyiDQzASJ4/OnMikr/OiCdZXx+agTzbJODGLO9qjHEMOgvr8N9wkO 5sLzz5+vl1XL+Yh6oaNihRRvlaSVZoMgvsSHrGQbuwDnOEZK7rXmM3gXU46RpMB8/J 2n4TuVYPULIaT9hR0Seb8iDtHYcETlB9LRkBhw9qT1kJIJOlOHAbm0LBGYxjIaZVwN zM9EnAcOEBa9GckvpLZbS28C48gf1Vph0kTP/9RQpCImedfVsMeozHpIiiMgJPFTh9 BGYmj/0mKMXWg== To: Maling list - DRI developers Cc: Linux Media Mailing List , =?utf-8?q?Niklas?= =?utf-8?q?_S=C3=B6derlund?= , Laurent Pinchart , Archit Taneja From: Hans Verkuil Subject: [PATCH] drm/bridge: adv7511: fix support for large EDIDs Message-ID: <904185be-19ea-a321-a227-d4e659fe1b68@xs4all.nl> Date: Wed, 24 Mar 2021 09:53:32 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Firefox/78.0 Thunderbird/78.7.1 MIME-Version: 1.0 Content-Language: en-US X-CMAE-Envelope: MS4xfNrjgwN9wqpC/KjMFiHEs1iNMh4C3iRxaZNAhNJJGzyKMVaiJjuAzQsRH2IcUY8myNGkUwwSf4ycnPWcKTzdq8rT+VqdjWa3i2Yci2OzPUbVcdjHf2i+ BSMUhjnjgUr6GL5+faqXubZJjxHPBbaw5ZJIMXnAWm8cbBqxjoxhwKIqbajScraLFAQBGW+Qi5FZyrLZWNKpsClQcGHGGB0yrgxiflAECegagcW6zOsOdrT/ j7nZehzZfeBL4bM97wwZ85uf0lPM0tPnA2We7yvmOtLZ/y/X1zkQyHRi07Bk5FUcYMqKGWqt0XESUiuxEupYMqz2PefBTZy7pCKwWPtaWUimF/RO8mMrJf+K jCypa6QQjyh4SX1yCMSWxzq2dthHuA== Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org While testing support for large (> 256 bytes) EDIDs on the Renesas Koelsch board I noticed that the adv7511 bridge driver only read the first two blocks. The media V4L2 version for the adv7511 (drivers/media/i2c/adv7511-v4l2.c) handled this correctly. Besides a simple bug when setting the segment register (it was set to the block number instead of block / 2), the logic of the code was also weird. In particular reading the DDC_STATUS is odd: this is unrelated to EDID reading. The reworked code just waits for any EDID segment reads to finish (this does nothing if the a segment is already read), checks if the desired segment matches the read segment, and if not, then it requests the new segment and waits again for the EDID segment to be read. Finally it checks if the currently buffered EDID segment contains the desired EDID block, and if not it will update the EDID buffer from the adv7511. Tested with my Koelsch board and with EDIDs of 1, 2, 3 and 4 blocks. Signed-off-by: Hans Verkuil Tested-by: Niklas Söderlund --- Testing on the Renesas board also requires these two adv7604 patches if you want to test with an HDMI cable between the HDMI input and output: https://patchwork.linuxtv.org/project/linux-media/patch/00882808-472a-d429-c565-a701da579ead@xs4all.nl/ https://patchwork.linuxtv.org/project/linux-media/patch/c7093e76-ffb4-b19c-f576-b264f935a3ce@xs4all.nl/ --- diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c index 76555ae64e9c..9e8db1c60167 100644 --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c @@ -328,6 +328,7 @@ static void adv7511_set_link_config(struct adv7511 *adv7511, static void __adv7511_power_on(struct adv7511 *adv7511) { adv7511->current_edid_segment = -1; + adv7511->edid_read = false; regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER, ADV7511_POWER_POWER_DOWN, 0); @@ -529,29 +530,35 @@ static int adv7511_get_edid_block(void *data, u8 *buf, unsigned int block, struct adv7511 *adv7511 = data; struct i2c_msg xfer[2]; uint8_t offset; + unsigned int cur_segment; unsigned int i; int ret; if (len > 128) return -EINVAL; - if (adv7511->current_edid_segment != block / 2) { - unsigned int status; + /* wait for any EDID segment reads to finish */ + adv7511_wait_for_edid(adv7511, 200); - ret = regmap_read(adv7511->regmap, ADV7511_REG_DDC_STATUS, - &status); + ret = regmap_read(adv7511->regmap, ADV7511_REG_EDID_SEGMENT, &cur_segment); + if (ret < 0) + return ret; + + /* + * If the current read segment does not match what we need, then + * write the new segment and wait for it to be read. + */ + if (cur_segment != block / 2) { + adv7511->edid_read = false; + cur_segment = block / 2; + regmap_write(adv7511->regmap, ADV7511_REG_EDID_SEGMENT, + cur_segment); + ret = adv7511_wait_for_edid(adv7511, 200); if (ret < 0) return ret; + } - if (status != 2) { - adv7511->edid_read = false; - regmap_write(adv7511->regmap, ADV7511_REG_EDID_SEGMENT, - block); - ret = adv7511_wait_for_edid(adv7511, 200); - if (ret < 0) - return ret; - } - + if (adv7511->current_edid_segment != cur_segment) { /* Break this apart, hopefully more I2C controllers will * support 64 byte transfers than 256 byte transfers */ @@ -579,7 +586,7 @@ static int adv7511_get_edid_block(void *data, u8 *buf, unsigned int block, offset += 64; } - adv7511->current_edid_segment = block / 2; + adv7511->current_edid_segment = cur_segment; } if (block % 2 == 0)