From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9280FC433E0 for ; Thu, 9 Jul 2020 20:04:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 75EE4207DD for ; Thu, 9 Jul 2020 20:04:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726336AbgGIUET (ORCPT ); Thu, 9 Jul 2020 16:04:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42410 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726193AbgGIUES (ORCPT ); Thu, 9 Jul 2020 16:04:18 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B3B91C08C5CE for ; Thu, 9 Jul 2020 13:04:18 -0700 (PDT) Received: from [IPv6:2003:cb:8737:cf00:f5ff:2fff:89f:f3f4] (p200300cb8737cf00f5ff2fff089ff3f4.dip0.t-ipconnect.de [IPv6:2003:cb:8737:cf00:f5ff:2fff:89f:f3f4]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: dafna) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 03A072A663A; Thu, 9 Jul 2020 21:04:16 +0100 (BST) Subject: Re: [libcamera-devel] [PATCH 03/25] media: ov5647: Add support for PWDN GPIO. To: Jacopo Mondi , mchehab@kernel.org, sakari.ailus@linux.intel.com, hverkuil@xs4all.nl, laurent.pinchart@ideasonboard.com, roman.kovalivskyi@globallogic.com, dave.stevenson@raspberrypi.org, naush@raspberrypi.com Cc: mrodin@de.adit-jv.com, hugues.fruchet@st.com, mripard@kernel.org, aford173@gmail.com, sudipi@jp.adit-jv.com, andrew_gabbasov@mentor.com, erosca@de.adit-jv.com, linux-media@vger.kernel.org, libcamera-devel@lists.libcamera.org References: <20200623100815.10674-1-jacopo@jmondi.org> <20200623100815.10674-4-jacopo@jmondi.org> From: Dafna Hirschfeld Message-ID: <5dbb468e-db42-6ac2-db40-196dc0f8a09f@collabora.com> Date: Thu, 9 Jul 2020 22:04:14 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200623100815.10674-4-jacopo@jmondi.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On 23.06.20 12:07, Jacopo Mondi wrote: > From: Dave Stevenson > > Add support for an optional GPIO connected to PWDN on the sensor. This > allows the use of hardware standby mode where internal device clock > and circuit activities are halted. > > Please note that power is off when PWDN is high. > > Signed-off-by: Dave Stevenson > Signed-off-by: Roman Kovalivskyi > Signed-off-by: Jacopo Mondi > --- > drivers/media/i2c/ov5647.c | 28 ++++++++++++++++++++++++++++ > 1 file changed, 28 insertions(+) > > diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c > index e7d2e5b4ad4b9..105ff7f899b34 100644 > --- a/drivers/media/i2c/ov5647.c > +++ b/drivers/media/i2c/ov5647.c > @@ -21,6 +21,7 @@ > > #include > #include > +#include > #include > #include > #include > @@ -35,6 +36,13 @@ > > #define SENSOR_NAME "ov5647" > > +/* > + * From the datasheet, "20ms after PWDN goes low or 20ms after RESETB goes > + * high if reset is inserted after PWDN goes high, host can access sensor's > + * SCCB to initialize sensor." > + */ > +#define PWDN_ACTIVE_DELAY_MS 20 > + > #define MIPI_CTRL00_CLOCK_LANE_GATE BIT(5) > #define MIPI_CTRL00_BUS_IDLE BIT(2) > #define MIPI_CTRL00_CLOCK_LANE_DISABLE BIT(0) > @@ -86,6 +94,7 @@ struct ov5647 { > unsigned int height; > int power_count; > struct clk *xclk; > + struct gpio_desc *pwdn; > }; > > static inline struct ov5647 *to_state(struct v4l2_subdev *sd) > @@ -355,6 +364,11 @@ static int ov5647_sensor_power(struct v4l2_subdev *sd, int on) > if (on && !ov5647->power_count) { > dev_dbg(&client->dev, "OV5647 power on\n"); > > + if (ov5647->pwdn) { > + gpiod_set_value_cansleep(ov5647->pwdn, 0); > + msleep(PWDN_ACTIVE_DELAY_MS); > + } > + > ret = clk_prepare_enable(ov5647->xclk); > if (ret < 0) { > dev_err(&client->dev, "clk prepare enable failed\n"); > @@ -392,6 +406,8 @@ static int ov5647_sensor_power(struct v4l2_subdev *sd, int on) > dev_dbg(&client->dev, "soft stby failed\n"); > > clk_disable_unprepare(ov5647->xclk); > + > + gpiod_set_value_cansleep(ov5647->pwdn, 1); > } > > /* Update the power count. */ > @@ -581,6 +597,10 @@ static int ov5647_probe(struct i2c_client *client) > return -EINVAL; > } > > + /* Request the power down GPIO asserted */ > + sensor->pwdn = devm_gpiod_get_optional(&client->dev, "pwdn", > + GPIOD_OUT_HIGH); Hi, I see that other drivers check for error from 'devm_gpiod_get_optional' using 'IS_ERR' Thanks, Dafna > + > mutex_init(&sensor->lock); > > sd = &sensor->sd; > @@ -594,7 +614,15 @@ static int ov5647_probe(struct i2c_client *client) > if (ret < 0) > goto mutex_remove; > > + if (sensor->pwdn) { > + gpiod_set_value_cansleep(sensor->pwdn, 0); > + msleep(PWDN_ACTIVE_DELAY_MS); > + } > + > ret = ov5647_detect(sd); > + > + gpiod_set_value_cansleep(sensor->pwdn, 1); > + > if (ret < 0) > goto error; > >