i.MX6UL: Failed to connect multiple SPI slaves devices to spi bus of imx6UL

[ganesh_k]

Dear NXP Team,

We are trying to connect multiple SPI salves (5 slaves) to i.MX6UL processor - SPI bus. But in our case only 4 slave devices are able to communicate with master(i.MX6UL), and unable to communicate with 5 slave. In a simple way only 4 slaves can be able to communicate over SPI bus irrespective of the number slave devices connected to it.

Is there any limitation in SPI master driver about this slave device connection?

Attaching the device tree configuration and the respective to SPI logs for your reference.

Please help us in this regards

Thanks,

Ganesh K

[kef2]

SNVS pads and non-SNVS pads can't be mixed in the same pinctrl groups. SNVS pads belong to iomuxc-snvs, while non-SNVS pads belong to iomuxc. 

[Sanket_Parekh]

Hi @ganesh_k 

I hope you are doing well.

Maximum limit of slave device connect with SPI master is 4. That is why 5th device was unable to connect at a time. For more reference one can refer Chapter 20 Enhanced Configurable SPI of IMX6UL Reference manual.

Thanks & Regards

Sanket Parekh

[kef2]

Only 4 HW CS's, unlimited GPIO CS's!

[ganesh_k]

Hi @Sanket_Parekh,

Thanks for the quick response. Will come back to you if any further information is needed in this regard.

Thanks,

Ganesh K

[Sanket_Parekh]

Hi @ganesh_k 

Any updates from your side?

If not, Can I mark this ticket to close state?

Thanks & Regards

Sanket Parekh