i.MX ProcessorsのトピックSPI driver Sabre lite

SPI driver Sabre lite

niklasmolin — Tue, 11 Feb 2014 03:02:54 GMT

Hi.

I'm trying the nitrogen6x build for the Sabre lite board and trying to enable the SPIdev driver (In Yocto).

I have changed the alias in the board-mx6_nitrogen6x.c file and also updated the defconfig (I think it's the right one) to enable SPIDEV etc.

But I still don't see spidev under /dev directory.

Is there anything else I'm missing here?

I managed to get it work when I was using sabrelite as "MACHINE", for about 2 months ago.

Thanks,

Niklas

Re: SPI driver Sabre lite

EricNelson — Tue, 11 Feb 2014 13:03:30 GMT

Hi Niklas,

The default kernel configuration has support for SPI. You can validate this by looking in /proc/mtd to see the flash partitions and you can run "hexdump -c /dev/mtd0r0" to see the content of SPI-NOR.

It seems that you're asking about userspace SPI access though (/dev/spi...). This isn't included in the standard kernel configuration, and you'd need to enable it by running "bitbake -c menuconfig linux-boundary".

I wonder why you're doing this though. Are you hooking up a different SPI device through other pins? If so, you'll need to change the pin-muxing for the SPI and chip-select pins and add another SPI bus to the system as shown here:

linux-imx6/arch/arm/mach-mx6/board-mx6_nitrogen6x.c at boundary-imx_3.0.35_4.1.0 · boundarydevices/linux-imx6 · GitHub

If you're doing this level of kernel hacking, I'd strongly recommend building the kernel outside of Yocto, so that you have a proper git repository backing your efforts.

Re: SPI driver Sabre lite

niklasmolin — Thu, 13 Feb 2014 15:28:56 GMT

Hi Eric.

Thanks for you reply.

This was definitely helpful, since we just wanted to access the flash to do some tests.

Thanks,

Niklas