From patchwork Mon Nov 13 12:56:38 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 10055853 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 4261A60586 for ; Mon, 13 Nov 2017 13:03:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4B3AA2951A for ; Mon, 13 Nov 2017 13:03:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3FF2F2951C; Mon, 13 Nov 2017 13:03:05 +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=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED 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 C62E72951A for ; Mon, 13 Nov 2017 13:03:04 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D30706E0F3; Mon, 13 Nov 2017 13:03:03 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) by gabe.freedesktop.org (Postfix) with ESMTPS id 24AAB6E0F3 for ; Mon, 13 Nov 2017 13:03:03 +0000 (UTC) Received: from localhost (LFbn-1-12253-150.w90-92.abo.wanadoo.fr [90.92.67.150]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 7A081ABB; Mon, 13 Nov 2017 13:03:02 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Subject: [PATCH 4.9 81/87] drm/bridge: adv7511: Re-write the i2c address before EDID probing Date: Mon, 13 Nov 2017 13:56:38 +0100 Message-Id: <20171113125622.533445512@linuxfoundation.org> X-Mailer: git-send-email 2.15.0 In-Reply-To: <20171113125615.304035578@linuxfoundation.org> References: <20171113125615.304035578@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Cc: Nhan Nguyen , David Airlie , Greg Kroah-Hartman , dri-devel@lists.freedesktop.org, stable@vger.kernel.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: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: John Stultz commit 3587c856675c45809010c2cee5b21096f6e8e938 upstream. 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 turns out that some of the register state in hardware is getting lost, as the device registers are reset when the chip is powered down. 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 Reviewed-by: Laurent Pinchart Tested-by: Laurent Pinchart Signed-off-by: John Stultz Signed-off-by: Archit Taneja Link: http://patchwork.freedesktop.org/patch/msgid/1484614372-15342-7-git-send-email-john.stultz@linaro.org Signed-off-by: Nhan Nguyen Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) --- 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 adv7 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)