How to write spi custom device driver for sensor

[Dhevan]

Hi,

I want to write custom linux spi device driver for imx8m mini.

Which kernal api and documentation i need to refer.

[AldoG]

Hello,

For this you may refer to the Linux kernel documentation:
https://www.kernel.org/doc/html/v4.19/driver-api/spi.html
Our test SPI driver:
https://source.codeaurora.org/external/imx/imx-test/tree/test/mxc_spi_test/mxc_spi_test1.c?h=lf-5.10... 
The i.MX SPI driver:
https://source.codeaurora.org/external/imx/linux-imx/tree/drivers/spi/spi-imx.c?h=lf-5.10.y

For documentation, you may also check our Linux documentation (i.MX Linux Reference Manual​) available for download here:
https://www.nxp.com/design/software/embedded-software/i-mx-software/embedded-linux-for-i-mx-applicat...

Best regards,
Aldo.

[Dhevan]

Hi @AldoG,

Thanks for your reply.

 If we wrote two independent kernel device driver our issue will resolve ?

I have another doubt's also.

kernel driver - spi-imx.c and spidev.c what will be the difference between these two driver?

Thanks & Regards,

      Vasu

[AldoG]

Hi,

Sorry I don't know what kind of issue are you referring to.

For difference, spi-imx is the SPI Master controller driver, while spidev is a userspace kernel driver.

You can refer to the following documentation:
https://source.codeaurora.org/external/imx/linux-imx/tree/Documentation/spi/spidev.rst?h=lf-5.10.y

Best regards,
Aldo.