From patchwork Tue Jan 17 00:52:52 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Stultz X-Patchwork-Id: 9519709 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 69B5D601C3 for ; Tue, 17 Jan 2017 00:53:10 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 552AC283FD for ; Tue, 17 Jan 2017 00:53:10 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 49F1F28494; Tue, 17 Jan 2017 00:53:10 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id D8545283FD for ; Tue, 17 Jan 2017 00:53:09 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E31A66E5A2; Tue, 17 Jan 2017 00:53:04 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-pg0-x22a.google.com (mail-pg0-x22a.google.com [IPv6:2607:f8b0:400e:c05::22a]) by gabe.freedesktop.org (Postfix) with ESMTPS id 38FC16E59A for ; Tue, 17 Jan 2017 00:53:03 +0000 (UTC) Received: by mail-pg0-x22a.google.com with SMTP id t6so14251220pgt.3 for ; Mon, 16 Jan 2017 16:53:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=IGTT6YVzGSFz2F9Zo1AJDGSlDu7UZzqYvjTPYrfDt3s=; b=KMC1R+a250oExvRJ9v8WxyZR5VBXeJvJ5XhTQ8VFfVX+BYBtFBRN2S62yLU52O6R/E eTImg+qoxzNAkLXBH5oITB/ADrexaPHnO9dU85PiIqXoOBSqCjAs++7nArs7yjnr98aH nvW1YKakJMcfKIs7vBwqu4hOn8YjcqhfXPIsk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=IGTT6YVzGSFz2F9Zo1AJDGSlDu7UZzqYvjTPYrfDt3s=; b=qrZRqTxyTxqhqSxmKuHrkMrzLWZKJX1fAUUnrJs9ipHn2EAtA3Cc0gvTOjmXZEGg7F XZJ5CRzd2UCt84cazvFzvk64kNqOjN9qOjTX8eYpzpkaBeHtJh6Vl5lHUKxuJk1J/SzL zDYkJpWRA6D2BZhIWYQ13V8yb8FLMY1LtSL9UW+vT2xcDpQFKhbs0Knrcr4f1+6yrKbT JjSH+c3PGXK64+YRDWKhu2r2VyBFgmnJmu9JDsFZYOqemG/e+MYgtHeVZzmBK9P5F8N3 pLYYrVm72lTOuA7OOcmDV7Rh9zFInqUxS2A9Lm0CVF2ldGZBBxU8Vym+/Wi/M4l/JyxL R2RQ== X-Gm-Message-State: AIkVDXLarwLzmGWWueZ0nMcMKmFHjwKSjsGKDIumkhJQceBLqdVc/iubZo9Tvt0xtPOqngIA X-Received: by 10.98.71.199 with SMTP id p68mr40551209pfi.104.1484614382426; Mon, 16 Jan 2017 16:53:02 -0800 (PST) Received: from localhost.localdomain ([2601:1c2:1002:83f0:4e72:b9ff:fe99:466a]) by smtp.gmail.com with ESMTPSA id q19sm50220516pfl.21.2017.01.16.16.53.01 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 16 Jan 2017 16:53:01 -0800 (PST) From: John Stultz To: lkml Subject: [PATCH 6/6] drm/bridge: adv7511: Re-write the i2c address before EDID probing Date: Mon, 16 Jan 2017 16:52:52 -0800 Message-Id: <1484614372-15342-7-git-send-email-john.stultz@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1484614372-15342-1-git-send-email-john.stultz@linaro.org> References: <1484614372-15342-1-git-send-email-john.stultz@linaro.org> Cc: dri-devel@lists.freedesktop.org, Wolfram Sang , Laurent Pinchart X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP I've found that by just turning the chip on and off via the POWER_DOWN register, I end up getting i2c_transfer errors on HiKey. Investigating further, it seems some of the register state in the regmap cache is getting lost, likely as the device registers were reset during power off. Thus this patch simply re-writes the i2c address to the ADV7511_REG_EDID_I2C_ADDR register to ensure its properly set before we try to read the EDID data. Cc: David Airlie Cc: Archit Taneja Cc: Wolfram Sang Cc: Lars-Peter Clausen Cc: Laurent Pinchart Cc: dri-devel@lists.freedesktop.org Signed-off-by: John Stultz Reviewed-by: Laurent Pinchart --- v4: New approach to make the EDID_I2C_ADDR register sane, as suggested by Laurent --- drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c index d216f61..0ed89ea 100644 --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c @@ -573,9 +573,17 @@ static int adv7511_get_modes(struct adv7511 *adv7511, unsigned int count; /* Reading the EDID only works if the device is powered */ - if (!adv7511->powered) + if (!adv7511->powered) { + unsigned int edid_i2c_addr = + (adv7511->i2c_main->addr << 1) + 4; + __adv7511_power_on(adv7511); + /* Reset the EDID_I2C_ADDR register as it might be cleared */ + regmap_write(adv7511->regmap, ADV7511_REG_EDID_I2C_ADDR, + edid_i2c_addr); + } + edid = drm_do_get_edid(connector, adv7511_get_edid_block, adv7511); if (!adv7511->powered)