LSM6DS3 linux driver for ODR of 1666 Hz

[Weden.1]

Hello STM,

looking the the mainline kernel for the IMU line, i see some comments in the code that say the only supported ODRs are that of up to 416 Hz. is it possible to run the sensor in high performance mode with the current linux driver? Is there a patchset that provides support for this or is this something that is unsupported with linux?

https://elixir.bootlin.com/linux/v5.12-rc8/source/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c#L18

regards,

wes

[Eleon BORLINI]

Hi wes @Weden.1​ ,

it should be possible -at least theoretically-, but I'm not an expert of these drivers.

Please refer to the Linux drivers on Github, for the specific product LSM6DS3 (st_lsm6ds3).

Here the limit is 416Hz too:

#define ST_LSM6DS3_ODR_416HZ_VAL		0x06

Probably it is enough to add a define with the values according to the codification you can find on the datasheet p.54.

 

But for these kind of requests I suggest you to open an issue directly on Github (LINK:( ST experts will help you, usually within a week.

Please keep me updated about your request.

-Eleon

[Weden.1]

Thanks Eleon for the quick response. I just submitted a ticket to the github link you suggested. I'll keep you posted on how it goes.

thanks for the help,

-wes

[Weden.1]

Hi Eleon,

i haven't heard back from anyone on the Github Issue link. is there somewhere else I could post, or some other person I could ask?

thanks,

-wes

[Eleon BORLINI]

Hi wes @Weden.1​ ,

Our internal experts (singular in fact, 1 expert...) has currently some problem to follow the Github issues due to requests overloading, but he is aware of the problem and (I hope) he'll reply soon.

Please keep checked in the next days whether there are updates on the topic.

-Eleon

[Weden.1]

any updates for this?

[Eleon BORLINI]

Hi @Weden.1​ ,

I wrote internally for help now, I'll keep you update in case of positive feedback.

-Eleon

[Eleon BORLINI]

Hi @Weden.1​ ,

here is the feedback from our expert:

with the current linux driver structure, it doesn't make sense to extend the support for ODR > 416Hz, since it wouldn't be guaranteed the handler execution. Something can be implemented if and only if the sensor is used in batching mode (decimation bits in FIFO_CTRL3 (08h) register, see datasheet p.48), in order to match the max ODR-416Hz condition, using the FIFO with high watermark values.

Let me please know if it can be feasible for you.

-Eleon