From: Javier Carrasco <javier.carrasco.cruz@gmail.com>
To: Jonathan Cameron <jic23@kernel.org>,
Lars-Peter Clausen <lars@metafoo.de>,
Li peiyu <579lpy@gmail.com>, Rob Herring <robh+dt@kernel.org>,
Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
Conor Dooley <conor+dt@kernel.org>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>,
linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org,
devicetree@vger.kernel.org,
Javier Carrasco <javier.carrasco.cruz@gmail.com>
Subject: [PATCH v2 3/3] iio: humidity: hdc3020: add reset management
Date: Mon, 26 Feb 2024 22:25:57 +0100 [thread overview]
Message-ID: <20240226-hdc3020-pm-v2-3-cec6766086e8@gmail.com> (raw)
In-Reply-To: <20240226-hdc3020-pm-v2-0-cec6766086e8@gmail.com>
The HDC3020 provides an active low reset signal that must be handled if
connected. Asserting this signal turns the device into Trigger-on Demand
measurement mode, reducing its power consumption when no measurements
are required like in low-power modes.
According to the datasheet, the longest "Reset Ready" is 3 ms, which is
only taken into account if the reset signal is defined.
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
---
drivers/iio/humidity/hdc3020.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/iio/humidity/hdc3020.c b/drivers/iio/humidity/hdc3020.c
index 6848be41e1c8..aa477b5e583e 100644
--- a/drivers/iio/humidity/hdc3020.c
+++ b/drivers/iio/humidity/hdc3020.c
@@ -15,6 +15,7 @@
#include <linux/cleanup.h>
#include <linux/crc8.h>
#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/interrupt.h>
@@ -70,6 +71,7 @@
struct hdc3020_data {
struct i2c_client *client;
+ struct gpio_desc *reset_gpio;
struct regulator *vdd_supply;
/*
* Ensure that the sensor configuration (currently only heater is
@@ -558,6 +560,9 @@ static int hdc3020_power_off(struct hdc3020_data *data)
{
hdc3020_exec_cmd(data, HDC3020_EXIT_AUTO);
+ if (data->reset_gpio)
+ gpiod_set_value_cansleep(data->reset_gpio, 1);
+
return regulator_disable(data->vdd_supply);
}
@@ -571,6 +576,11 @@ static int hdc3020_power_on(struct hdc3020_data *data)
fsleep(5000);
+ if (data->reset_gpio) {
+ gpiod_set_value_cansleep(data->reset_gpio, 0);
+ fsleep(3000);
+ }
+
if (data->client->irq) {
/*
* The alert output is activated by default upon power up,
@@ -627,6 +637,12 @@ static int hdc3020_probe(struct i2c_client *client)
return dev_err_probe(&client->dev, PTR_ERR(data->vdd_supply),
"Unable to get VDD regulator\n");
+ data->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(data->reset_gpio))
+ return dev_err_probe(&client->dev, PTR_ERR(data->reset_gpio),
+ "Cannot get reset GPIO\n");
+
ret = hdc3020_power_on(data);
if (ret)
return dev_err_probe(&client->dev, ret, "Power on failed\n");
--
2.40.1
prev parent reply other threads:[~2024-02-26 21:26 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-02-26 21:25 [PATCH v2 0/3] iio: humidity: hdc3020: add power and reset management Javier Carrasco
2024-02-26 21:25 ` [PATCH v2 1/3] iio: humidity: hdc3020: add power management Javier Carrasco
2024-03-03 16:31 ` Jonathan Cameron
2024-03-03 20:05 ` Javier Carrasco
2024-02-26 21:25 ` [PATCH v2 2/3] dt-bindings: iio: humidity: hdc3020: add reset-gpios Javier Carrasco
2024-02-27 7:50 ` Krzysztof Kozlowski
2024-02-26 21:25 ` Javier Carrasco [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20240226-hdc3020-pm-v2-3-cec6766086e8@gmail.com \
--to=javier.carrasco.cruz@gmail.com \
--cc=579lpy@gmail.com \
--cc=Jonathan.Cameron@huawei.com \
--cc=conor+dt@kernel.org \
--cc=devicetree@vger.kernel.org \
--cc=jic23@kernel.org \
--cc=krzysztof.kozlowski+dt@linaro.org \
--cc=lars@metafoo.de \
--cc=linux-iio@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=robh+dt@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).