Invensense MPU6500 driver with Digital Motion Processor (DMP)

[Daniel Baluta <daniel.baluta@intel.com>]

Hi Nathan/Ge,

I'm playing with Invensense MPU6500 device but I'm having problems
receiving data when the DPM is enabled.

I've rebased the code from 3.4 [1] on top of the latest iio git
tree. Without DMP enabled, I see interrupts arriving and I can
read data from /dev/iio:device0.

I'm using the following sequence for test:

sysfs_dev=/sys/bus/iio/devices/iio:device0

#Write dmp fw
fw_loaded=`cat ${sysfs_dev}/firmware_loaded`
if [ $fw_loaded -eq 0 ]; then
     fwtool write /bin/fw.bin
fi

#Enable accel
echo 0 > ${sysfs_dev}/buffer/enable
echo 200 > ${sysfs_dev}/sampling_frequency
echo 1 > ${sysfs_dev}/accel_fifo_enable
echo 1 > ${sysfs_dev}/accel_enable
echo 1 > ${sysfs_dev}/gyro_fifo_enable
echo 1 > ${sysfs_dev}/gyro_enable
#echo 1 > ${sysfs_dev}/master_enable

#Enable DMP
echo 1 > ${sysfs_dev}/dmp_on
echo 1 > ${sysfs_dev}/dmp_int_on
echo 1 > ${sysfs_dev}/dmp_event_int_on
echo 1 > ${sysfs_dev}/buffer/enable

cat /dev/iio\:device0

Now, the problem is that there is not interrupt triggered. Have you 
faced similar issues? Is there something wrong with the above sequence? 
 
 



thanks,
Daniel.

[1] 
https://android.googlesource.com/kernel/msm/+/android-msm-hammerhead-3.4-kk-fr2/drivers/staging/iio/imu/inv_mpu