Clock out on Low/High speed connectors


#1

Hi,

Is there any possibility of getting a configurable clock out on low/high speed connectors on the dragon board? I need a clock that is configurable from 1024Hz to 4096Hz with a minimum step less than 128Hz. I don’t need duty cycle control.
uname -a returns the following -
Linux linaro-developer 4.4.9-linaro-lt-qcom #1 SMP PREEMPT Thu Jun 30 21:34:48 UTC 2016 aarch64 GNU/Linux

Regards
Bharath


#2

cat /sys/kernel/debug/pinctrl/1000000.pinctrl/pinmux-functions | grep clk
returned the following -
function: cam_mclk0, groups = [ gpio26 ]
function: cam_mclk1, groups = [ gpio27 ]
function: dmic0_clk, groups = [ gpio0 ]
function: gcc_gp1_clk_a, groups = [ gpio49 ]
function: gcc_gp1_clk_b, groups = [ gpio97 ]
function: gcc_gp2_clk_a, groups = [ gpio50 ]
function: gcc_gp2_clk_b, groups = [ gpio12 ]
function: gcc_gp3_clk_a, groups = [ gpio51 ]
function: gcc_gp3_clk_b, groups = [ gpio13 ]
function: qdss_traceclk_a, groups = [ gpio46 ]
function: qdss_traceclk_b, groups = [ gpio5 ]

But I dont know how to get any of these clocks out on the pins. gpio12/13 are brought out on the Low speed connecter on the dragonboard. But, I dont know how to change the pinmux configurations on the pins to enable gcc_gp3_clk_b or gcc_gp2_clk_b.

Regards
Bharath