Adding i2c read/write support in Little Kernel

Products Support DragonBoard410c
#1

Hi All,

I am using little kernel in 410.

I have a requirement of reading and writing on I2C Expander (on i2c bus no. 3) in little Kernel.

It has default support of initialization, reading and writing for I2C-0 interface.

Now I want to in do initialization for I2C-3 interface.

Pinmuxing and other basic stuff had implemented. But I am finding some solution to enable clock for this i2c-3 controller clock.

I need pll configuration for enabling clock for this i2c-3 controller.

Can any body please guide me with some pointer to make it done.

Thanks.

#2

Hi,

I’m actually trying to figure out how to support I2C in LK as well. It looks like you’ve already resolved it for i2C-0. Would it be possible to share the code? If not, could you give some hints what needs to be done?
I can see a i2c_ssbi source code in the dev directory, but unfortunately using (without any mods) on Dragonboard 410c just crashes when an I2C commands is sent. I guess I need to set up different address base. Any info would be appreciated.
Thanks

#3

OK. Found it out. It’s described here: lm80-p0436-5_peripherals_programming_guide.pdf, chapter 4.2.1 Test code