From patchwork Wed Dec 3 15:34:48 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Yan X-Patchwork-Id: 5435431 Return-Path: X-Original-To: patchwork-dri-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 498419F72D for ; Thu, 4 Dec 2014 04:51:30 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 77DDA2028D for ; Thu, 4 Dec 2014 04:51:29 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id B07DB20253 for ; Thu, 4 Dec 2014 04:51:27 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3EDA26E813; Wed, 3 Dec 2014 20:51:08 -0800 (PST) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from lucky1.263xmail.com (lucky1.263xmail.com [211.157.147.131]) by gabe.freedesktop.org (Postfix) with ESMTP id 0D26A73559 for ; Wed, 3 Dec 2014 07:35:20 -0800 (PST) Received: from andy.yan?rock-chips.com (unknown [192.168.167.87]) by lucky1.263xmail.com (Postfix) with SMTP id 690661052A; Wed, 3 Dec 2014 23:35:15 +0800 (CST) X-263anti-spam: KSV:0; X-MAIL-GRAY: 1 X-MAIL-DELIVERY: 0 X-KSVirus-check: 0 X-ABS-CHECKED: 4 Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.263.net (Postfix) with ESMTP id F378341F5; Wed, 3 Dec 2014 23:35:15 +0800 (CST) X-RL-SENDER: andy.yan@rock-chips.com X-FST-TO: airlied@linux.ie X-SENDER-IP: 127.0.0.1 X-LOGIN-NAME: andy.yan@rock-chips.com X-UNIQUE-TAG: <99cd3793ce8e67dc57a6f00628fedf86> X-ATTACHMENT-NUM: 0 X-SENDER: yxj@rock-chips.com X-DNS-TYPE: 0 Received: from localhost.localdomain (unknown [127.0.0.1]) by smtp.263.net (Postfix) whith ESMTP id 6946CKMAMG; Wed, 03 Dec 2014 23:35:18 +0800 (CST) From: Andy Yan To: airlied@linux.ie, Philipp Zabel , heiko@sntech.de, fabio.estevam@freescale.com, rmk+kernel@arm.linux.org.uk Subject: [PATCH v16 09/12] drm: bridge/dw_hdmi: clear i2cmphy_stat0 reg in hdmi_phy_wait_i2c_done Date: Wed, 3 Dec 2014 23:34:48 +0800 Message-Id: <1417620888-30781-1-git-send-email-andy.yan@rock-chips.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1417620408-30354-1-git-send-email-andy.yan@rock-chips.com> References: <1417620408-30354-1-git-send-email-andy.yan@rock-chips.com> X-Mailman-Approved-At: Wed, 03 Dec 2014 20:51:00 -0800 Cc: Mark Rutland , dri-devel@lists.freedesktop.org, ykk@rock-chips.com, devel@driverdev.osuosl.org, Arnd Bergmann , linux-rockchip@lists.infradead.org, Grant Likely , Dave Airlie , jay.xu@rock-chips.com, devicetree@vger.kernel.org, Zubair.Kakakhel@imgtec.com, Pawel Moll , Ian Campbell , Rob Herring , mark.yao@rock-chips.com, Josh Boyer , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, djkurtz@google.com, Kumar Gala , Andy Yan , vladimir_zapolskiy@mentor.com 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-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_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 HDMI_IH_I2CMPHY_STAT0 is a clear on write register, which indicates i2cm operation status(i2c transfer done or error), every hdmi phy register configuration must check this register to make sure the configuration has complete. But the indication bit should be cleared after check, otherwise the corresponding bit will hold on forever, this may give a wrong signal for next check. Signed-off-by: Andy Yan --- Changes in v16: None Changes in v15: None Changes in v14: None Changes in v13: None Changes in v12: None Changes in v11: None Changes in v10: None Changes in v9: None Changes in v8: None Changes in v7: None Changes in v6: None Changes in v5: None Changes in v4: None Changes in v3: None drivers/gpu/drm/bridge/dw_hdmi.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/dw_hdmi.c b/drivers/gpu/drm/bridge/dw_hdmi.c index e3999da..e53dae0 100644 --- a/drivers/gpu/drm/bridge/dw_hdmi.c +++ b/drivers/gpu/drm/bridge/dw_hdmi.c @@ -666,11 +666,15 @@ static inline void hdmi_phy_test_dout(struct dw_hdmi *hdmi, static bool hdmi_phy_wait_i2c_done(struct dw_hdmi *hdmi, int msec) { - while ((hdmi_readb(hdmi, HDMI_IH_I2CMPHY_STAT0) & 0x3) == 0) { + u32 val; + + while ((val = hdmi_readb(hdmi, HDMI_IH_I2CMPHY_STAT0) & 0x3) == 0) { if (msec-- == 0) return false; udelay(1000); } + hdmi_writeb(hdmi, val, HDMI_IH_I2CMPHY_STAT0); + return true; }