Re: [PATCH v6 1/4] iio: pressure: bmp280: Use sleep and forced mode for oneshot captures

Andy Shevchenko
2024-09-13T09:52:02Z

On Fri, Sep 13, 2024 at 01:32:31AM +0200, Vasileios Amoiridis wrote:
> Add forced mode support in sensors BMP28x, BME28x, BMP3xx and BMP58x.
> Sensors BMP18x and BMP085 are old and do not support this feature so
> their operation is not affected at all.
>
> Essentially, up to now, the rest of the sensors were used in normal mode
> all the time. This means that they are continuously doing measurements
> even though these measurements are not used. Even though the sensor does
> provide PM support, to cover all the possible use cases, the sensor needs
> to go into sleep mode and wake up whenever necessary.
>
> The idea is that the sensor is by default in sleep mode, wakes up in
> forced mode when a oneshot capture is requested, or in normal mode
> when the buffer is enabled. The difference lays in the fact that in
> forced mode, the sensor does only one conversion and goes back to sleep
> while in normal mode, the sensor does continuous measurements with the
> frequency that was set in the ODR registers.
>
> The bmpX_chip_config() functions which are responsible for applying
> the requested configuration to the sensor, are modified accordingly
> in order to set the sensor by default in sleep mode.
>
> DEEP STANDBY, Low Power NORMAL and CONTINUOUS modes, supported only by
> the BMP58x version, are not added.

...

> + if (!((reg & BMP380_STATUS_DRDY_PRESS_MASK) &&
> + (reg & BMP380_STATUS_DRDY_TEMP_MASK))) {

I would add one more space to make the indentation follow the logic.

(no need to resend until Jonathan asks for it, otherwise I believe
he can amend this whilst applying)

> + dev_err(data->dev, "Measurement cycle didn't complete.\n");
> + return -EBUSY;
> + }

...

> + /*
> + * According to the BMP3 Sensor API, the sensor needs 5000us

Can we use 5ms...

> + * in order to go to the sleep mode.
> + */
> + fsleep(5000);

...and 5 * USEC_PER_MSEC here respectively?

--
With Best Regards,
Andy Shevchenko