Accessing I2C_SLV0* registers in burst mode (MPU9250/SPI)

Hi,
We are developing DMA based driver for MPU9250, and everything works perfect except part responsible for accessing magnetometer.
We are using MPU9250 connected via SPI interface and it's internal registers I2C_SLV0_ADDR/I2C_SLV0_REG/I2C_SLV0_CTRL for making connection to AK8963 magnetometer.
We have problems with burst write (3 bytes) starting from register I2C_SLV0_ADDR (0x25). It does not work, the data seems to be not transfered by internal I2C to AK8963 device.
Please see pictures below including signals registered on SPI lines.
https://copy.com/xwgfZTvEoUwOqOXv
https://copy.com/NrjUhET2vsbcz2fp
It looks like there is need of small delay (1ms is enough) between writing to I2C_SLV0_ADDR and I2C_SLV0_REG and I2C_SLV0_CTRL. Is it true?
I can't find any detailed information regarding accessing AK8963 registers. (time limits?)

Best regards
Krzysiek