From patchwork Mon Nov 17 10:57:56 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Yan X-Patchwork-Id: 5327701 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 54F839F818 for ; Tue, 18 Nov 2014 11:26:26 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 3D75320176 for ; Tue, 18 Nov 2014 11:26:25 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 2A3122012B for ; Tue, 18 Nov 2014 11:26:24 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 36CDA6E47F; Tue, 18 Nov 2014 03:26:05 -0800 (PST) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from regular1.263xmail.com (regular1.263xmail.com [211.150.99.140]) by gabe.freedesktop.org (Postfix) with ESMTP id 8C6F16E4A4 for ; Mon, 17 Nov 2014 02:58:12 -0800 (PST) Received: from andy.yan?rock-chips.com (unknown [192.168.167.140]) by regular1.263xmail.com (Postfix) with SMTP id D51CB3E25; Mon, 17 Nov 2014 18:58:08 +0800 (CST) X-263anti-spam: KSV:0; X-MAIL-GRAY: 0 X-MAIL-DELIVERY: 1 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 DF46943B; Mon, 17 Nov 2014 18:58:02 +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: <50b4725e3515221c6aca88560fe06568> 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 9347ROPDU3; Mon, 17 Nov 2014 18:58:05 +0800 (CST) From: Andy Yan To: airlied@linux.ie, heiko@sntech.de, fabio.estevam@freescale.com, rmk+kernel@arm.linux.org.uk Subject: [PATCH v12 08/11] drm: bridge/dw_hdmi: clear i2cmphy_stat0 reg in hdmi_phy_wait_i2c_done Date: Mon, 17 Nov 2014 18:57:56 +0800 Message-Id: <1416221876-13173-1-git-send-email-andy.yan@rock-chips.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1415793593-5075-1-git-send-email-andy.yan@rock-chips.com> References: <1415793593-5075-1-git-send-email-andy.yan@rock-chips.com> X-Mailman-Approved-At: Tue, 18 Nov 2014 03:25:51 -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 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 v12: None Changes in v11: - split form patch 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 Changes in v2: 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 7b32bb8..898488d 100644 --- a/drivers/gpu/drm/bridge/dw_hdmi.c +++ b/drivers/gpu/drm/bridge/dw_hdmi.c @@ -668,11 +668,15 @@ 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; }