Re: Use LIS3MDL with LSM6DSM sensor-hub

[Lorenzo Bianconi <lorenzo@kernel.org>]

[-- Attachment #1: Type: text/plain, Size: 3147 bytes --]

> On 2020-03-19 21:49, Lorenzo Bianconi wrote:
> > > On 2020-03-19 18:40, Lorenzo Bianconi wrote:
> > > > > On 2020-03-14 13:43, Lorenzo Bianconi wrote:
> > > > > > On Mar 11, Jimmy Assarsson wrote:
> > > > > > > Hi,
> > > > > > > 
> > 
> > [...]
> > 
> > > > > > Hi Jimmy,
> > > > > > 
> > > > > > in order to set the full scale on LIS3MDL you can try the following patch (just
> > > > > > compiled, not tested)
> > > > > > 
> > > > > > Regards,
> > > > > > Lorenzo
> > > > > 
> > > > > Hi Lorenzo,
> > > > > 
> > > > > Sorry for the late response and thanks for the patch!
> > > > 
> > > > Hi Jimmy,
> > > > 
> > > > ok, I will post the patch, thx for testing.
> > > 
> > > Great, you can add
> > > Tested-by: Jimmy Assarsson <jimmyassarsson@gmail.com>
> > > 
> > > > > The patches seems to work.
> > > > > Are there any specific tests that we should carry out?
> > > > > Via the sysfs interface, we've tested reading raw values of each channel and
> > > > > configuring ODR and full scale.
> > > > 
> > > > you can try to enable batching in the hw FIFO doing something like:
> > > > 
> > > > $echo 1 > /sys/bus/iio/devices/<iio-magn>/scan_elements/in_magn_x_en
> > > > $echo 1 > /sys/bus/iio/devices/<iio-magn>/scan_elements/in_magn_y_en
> > > > $echo 1 > /sys/bus/iio/devices/<iio-magn>/scan_elements/in_magn_z_en
> > > > $echo 1 > /sys/bus/iio/devices/<iio-magn>/scan_elements/in_timestamp_en
> > > > 
> > > > $watermark=64
> > > > $echo $((2*watermark)) > /sys/bus/iio/devices/<iio-magn>/buffer/length
> > > > $echo $watermark > /sys/bus/iio/devices/<iio-magn>/buffer/watermark
> > > > 
> > > > $generic_buffer -gn lsm6dsm_magn -c <# of samples>
> > > 
> > > Ok. I don't got any scan_elements nor buffer directory, for any of the devices.
> > > I guess it is not possible to use the FIFO without configuring any interrupt?
> > > We got the following dts:
> > > &spi1 {
> > > 	#address-cells = <1>;
> > > 	#size-cells = <0>;
> > > 	lsm6dsm@0 {
> > > 		compatible = "st,lsm6dsm";
> > > 		reg = <0x0>;
> > > 
> > > 		spi-max-frequency = <500000>;
> > > 		st,pullups = "true";
> > 
> > yes, you need to provide the interrupt line doing something like (this is from
> > the dts on my rpi):
> > 
> > 	lsm6dsm@0 {
> > 		...
> > 		interrupt-parent = <&gpio>;
> > 		interrupts = <21 0x4>;
> > 		...
> > 	};
> > 
> > > 	};
> > > };
> > > 
> > > I'll look into this tomorrow or in the beginning of next week, thanks for the help.
> 
> Now I've tested this. It looks fine, except for the very first sample:
> $ ./iio_generic_buffer -gn lsm6dsm_magn -c 1
> iio device number being used is 3
> trigger-less mode selected
> -3.250836 -2.796192 10.212408 1584976428879020199
> 1.893036 2.343738 -0.853224 1584976428917070199
> 1.888218 2.343300 -0.852786 1584976428955095199
> 1.888218 2.343300 -0.852786 1584976428993145199
> 1.889532 2.345490 -0.851472 1584976429031170199

values seems reasonable but I guess it depends on sensor calibration and how is
oriented. Do you have any app to test it?

Regards,
Lorenzo

> 
> Is this expected?
> 
> Regards,
> jimmy

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]