From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751026AbdJAKW4 (ORCPT ); Sun, 1 Oct 2017 06:22:56 -0400 Received: from mail-pg0-f68.google.com ([74.125.83.68]:36357 "EHLO mail-pg0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750849AbdJAKWy (ORCPT ); Sun, 1 Oct 2017 06:22:54 -0400 X-Google-Smtp-Source: AOwi7QDw/AGr35LQqxdnUiB//NNSq320JeNw/5r8U01Xs+FZxvKJYSZXfmiCZuf3yXeo3Llgk2OT6A== From: Jacob Chen To: linux-media@vger.kernel.org Cc: linux-kernel@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 v3 1/2] media: i2c: OV5647: ensure clock lane in LP-11 state before streaming on Date: Sun, 1 Oct 2017 18:22:37 +0800 Message-Id: <20171001102238.21585-1-jacob-chen@iotwrt.com> X-Mailer: git-send-email 2.14.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 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 95ce90fdb876..247302d01f53 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) -- 2.14.1