how to get or initialize clock in L4Linux

Martin Schröder martin.schroeder at
Fri Aug 8 12:20:45 CEST 2014

Hi Yunchuan,

Am 08.08.2014 um 10:49 schrieb Yunchuan Geng:
> Hi, L4hackers,
> I am implementing I2C drivers from native linux to L4Linux. I am using
> Freescale iMX6Q SD board. Kernel version 3.14
> in ./drivers/i2c/busses/i2c-imx.c, function i2c_imx_probe(),
> devm_clk_get() is called. And fails at here. I understand that clock are
> initialized from function "__init imx6q_clocks_init()".
> I managed to compile and call the imx6q_clocks_init() function from
> L4Linux, but encountered many problem.
> The question is, Is it necessary to initialize clocks in L4Linux and how?

I had the same problem with clocking of the network driver in 
fec_main.c. My approach is to do the clock setup outside of l4linux, 
preferably let the bootloader (U-Boot) do this for me. So when the 
driver is probed all clock setup can be skipped in the driver.


More information about the l4-hackers mailing list