Driver Development : SPI or 4 wire Interface on BBB

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1

I am developing a driver for a hardware whose datasheet says it has a 4 wire Serial interface .DataIN/OUT,Clock,CS .Does it means I can develop a full fledged SPI driver on Linux to use it.
To add more when the CLK has n-n+1(say 3-4) rising edge with LE = 1 certain control register will be written .Value of n depends on the type of control register.
Will it be good to develop a SPI driver for this or this can be achieved better by using the GPIOs(setting/resetting the CLK,Data Lines) .

experts comments required.
Rp

2

Here are the possible solutions:

  1. Use spidev which allows a user space application to communicate with a device over SPI
  2. Use PRU to communicate with device over SPI
  3. Develop a device driver to communicate with device over SPI
  4. Adapt an IIO driver that is similar to your device

Regards,
John

3

My Question was Can CS be selectively made High or Low at nth or pth Clock Pulse while using/writing the SPI driver?

4

Best to use the PRU and control the I/O with software.

Regards,
John

5

Most SPI peripheral can control the CS automatically. The TRM will tell you if you can meet your timing diagrams. If it doesn’t you need to use a GPIO control of CLK in software

6

What is PRU?Can you post a link or keywords related to it.?

7

Just Google “am335x pru”

http://processors.wiki.ti.com/index.php/PRU-ICSS

Regards,
John