SPI master on Colibri i.MX7D

Hello,
My environment is: Toradex Colibri iMX7 Dual Module 512MB V1.1C.
I wish I could use the device spi 3 (ecspi3) in master mode with 2 slave device. One using a chip select on pin gpio4 11 (pin SS0 spi3) (sodimm 86) and the other using pin gpio4 7 (sodimm 129) not dedicated to spi 3 controller.
Is this possible, if so how? Or is it only possible to use the 4 pin SS dedicated to spi3. In this case, can you confirm that it is not possible to manage more than 4 devices per SPI controller.

Thanking you.

Regards,

@paul.goulpie, please let us know which OS you plan to use. Linux or Windows Embedded Compact? In general it should be possible to use GPIOs as chip select and therefore could use as many slaves as you have GPIOs available. The software needs of course to control them correctly. If you let us know which OS you want to use, we might have some more hints.

Hello,
I just figured out why the SPI3 CS on pin gpio4 7 (sodimm 129) was not working. This one was already declared as used in the device tree for the reg_usb_otg_vbus. After disabling this one everything works perfectly. For information I am on a Linux environment with a BSP owner (kernel 4.9 vanilla).
Thank you for your answers.

Regards,