From patchwork Wed Nov 4 10:35:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacopo Mondi X-Patchwork-Id: 11880199 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 076D014C0 for ; Wed, 4 Nov 2020 10:36:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E39AB21734 for ; Wed, 4 Nov 2020 10:36:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729097AbgKDKgq (ORCPT ); Wed, 4 Nov 2020 05:36:46 -0500 Received: from relay7-d.mail.gandi.net ([217.70.183.200]:44723 "EHLO relay7-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728287AbgKDKgp (ORCPT ); Wed, 4 Nov 2020 05:36:45 -0500 X-Originating-IP: 93.34.118.233 Received: from uno.lan (93-34-118-233.ip49.fastwebnet.it [93.34.118.233]) (Authenticated sender: jacopo@jmondi.org) by relay7-d.mail.gandi.net (Postfix) with ESMTPSA id AE7A820011; Wed, 4 Nov 2020 10:36:42 +0000 (UTC) From: Jacopo Mondi To: linux-media@vger.kernel.org Cc: Jacopo Mondi , mchehab@kernel.org, sakari.ailus@linux.intel.com, hverkuil@xs4all.nl, laurent.pinchart@ideasonboard.com, roman.kovalivskyi@globallogic.com, dafna.hirschfeld@collabora.com, dave.stevenson@raspberrypi.org, naush@raspberrypi.com, erosca@de.adit-jv.com Subject: [PATCH v2 02/30] media: ov5647: Add support for PWDN GPIO. Date: Wed, 4 Nov 2020 11:35:54 +0100 Message-Id: <20201104103622.595908-3-jacopo@jmondi.org> X-Mailer: git-send-email 2.29.1 In-Reply-To: <20201104103622.595908-1-jacopo@jmondi.org> References: <20201104103622.595908-1-jacopo@jmondi.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org 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 | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c index e7d2e5b4ad4b9..5dde138763eb0 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 +597,14 @@ 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); + if (IS_ERR(sensor->pwdn)) { + dev_err(dev, "Failed to get 'pwdn' gpio\n"); + return -EINVAL; + } + mutex_init(&sensor->lock); sd = &sensor->sd; @@ -594,7 +618,15 @@ 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;