Incorporating External Spi Flash vin-supply/supply-gpio

[frambow_i]

Hi

I'm currently trying to set up an external flash (s25FL064L) that is power controlled by a GPIO pin switching a generic Mosfet to power the flash only when needed. I'm using a NRF9160 as the MCU. 

While there is either the SUPPLY node in the compatible Jedec SPI-NOR flash resulting in a supply-gpio attribute in the devicetree, which doesn't seem to be be turning the gpio pin on itself. There is also a vin-supply attribute that only accepts a regulator node which I was not able to correctly configure to just switch the corresponding gpio pin. 

Has anyone of you any experience in a related problem or can help me finding out how to properly solve my problem ? 

[Sigurd Hellesvik]

Hi,

I searched for "supply-gpios" in a previous ticket:  Question about supply-gpios specification in dts file . I think the answer here is the same: supply-gpios is not used in this case, so the drivers are responsible for handling that.

Maybe the easiest way here is to use the Power Management features to "trick" zephyr into toggling that pin for you?
You see, if you use Power Management, the SPI-NOR driver will do some stuff on power management.
Now, you can also implement custom things that happen on power management, and use that to toggle supply-gpios.

The most proper method would be to implement a new custom driver for your external flash setup, which uses supply-gpios, I think.

Does this answer your question?

Regards,
Sigurd Hellesvik