Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752177AbdIKBxy (ORCPT ); Sun, 10 Sep 2017 21:53:54 -0400 Received: from mail-pf0-f193.google.com ([209.85.192.193]:38719 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752055AbdIKBxw (ORCPT ); Sun, 10 Sep 2017 21:53:52 -0400 X-Google-Smtp-Source: ADKCNb5AtfeyI7Y3ETmvEJoZTumoPQ7XI67LtrO6wZ002KH6pYNftcRK+aLL37voAaFh1In8/3lpqg== From: Jacob Chen To: linux-rockchip@lists.infradead.org Cc: linux-kernel@vger.kernel.org, roliveir@synopsys.com, linux-media@vger.kernel.org, mchehab@kernel.org, vladimir_zapolskiy@mentor.com, hans.verkuil@cisco.com, sakari.ailus@linux.intel.com, lolivei@synopsys.com, p.zabel@pengutronix.de, Jacob Chen Subject: [PATCH] media: i2c: OV5647: ensure clock lane in LP-11 state before streaming on Date: Mon, 11 Sep 2017 09:53:40 +0800 Message-Id: <1505094820-11958-1-git-send-email-jacob-chen@iotwrt.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1712 Lines: 67 When I was supporting Rpi Camera Module on the ASUS Tinker board, I found this driver have some issues with rockchip's mipi-csi driver. It didn't place clock lane in LP-11 state before performing D-PHY initialisation. >From our experience, on some OV sensors, LP-11 state is not achieved while BIT(5)-0x4800 is cleared. So let's set BIT(5) and BIT(0) both while not streaming, in order to coax the clock lane into LP-11 state. 0x4800 : MIPI CTRL 00 BIT(5) : clock lane gate enable 0: continuous 1: none-continuous BIT(0) : manually set clock lane 0: Not used 1: used Changes in V2: modify commit messages Signed-off-by: Jacob Chen --- drivers/media/i2c/ov5647.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c index 95ce90f..247302d 100644 --- a/drivers/media/i2c/ov5647.c +++ b/drivers/media/i2c/ov5647.c @@ -253,6 +253,10 @@ static int ov5647_stream_on(struct v4l2_subdev *sd) { int ret; + ret = ov5647_write(sd, 0x4800, 0x04); + if (ret < 0) + return ret; + ret = ov5647_write(sd, 0x4202, 0x00); if (ret < 0) return ret; @@ -264,6 +268,10 @@ static int ov5647_stream_off(struct v4l2_subdev *sd) { int ret; + ret = ov5647_write(sd, 0x4800, 0x25); + if (ret < 0) + return ret; + ret = ov5647_write(sd, 0x4202, 0x0f); if (ret < 0) return ret; @@ -320,7 +328,10 @@ static int __sensor_init(struct v4l2_subdev *sd) return ret; } - return ov5647_write(sd, 0x4800, 0x04); + /* + * stream off to make the clock lane into LP-11 state. + */ + return ov5647_stream_off(sd); } static int ov5647_sensor_power(struct v4l2_subdev *sd, int on) -- 2.7.4