Re: [PATCH] iio: gyro: bmg160: wait full startup time after mode change at probe

[Andy Shevchenko]

On Mon, May 11, 2026 at 11:27:55AM +0500, Stepan Ionichev wrote:
> bmg160_chip_init() calls bmg160_set_mode(BMG160_MODE_NORMAL) and
> then waits only 500-1000 us. Per the BMG160 datasheet
> (BST-BMG160-DS000-07 Rev. 1.0, May 2013), the start-up and wake-up
> times (tsu, twusm) are 30 ms.
> 
> The same file already waits BMG160_MAX_STARTUP_TIME_MS (80 ms)
> in bmg160_runtime_resume() after the same set_mode(NORMAL)
> operation. The 500 us value at probe was likely a unit mix-up;
> the old comment said "500 ms" while the code used microseconds.
> 
> Reuse the same constant via msleep_interruptible() to match the
> runtime resume path. Without this, register writes that follow
> the mode change can hit the chip before it is ready.

...

> -	/* Wait upto 500 ms to be ready after changing mode */

First of all, the same comment, put better description on "why?"
based on the datasheet explanation.

> -	usleep_range(500, 1000);
> +	msleep_interruptible(BMG160_MAX_STARTUP_TIME_MS);

Hmm... This returns an error in case it's aborted by a signal or other means.
What are you supposed to do with that?

-- 
With Best Regards,
Andy Shevchenko