Hi,
Currently, We're doing EMC testing for our product that using imx6dl and camera ov5640.
Now, we want to change frequency of mclk for ov5640_mipi. It's default value is 24Mhz.
I tried change mclk with many difference value from device tree but it still got measuring result from Oscilloscope is 24Mhz.
My question is if above solutions is not correct . So, is there any way to change this frequency of mclk?
Kernel version we 're using is Linux 4.1.15.
Thanks & Best Regards,
Dong
Hi Dong
clocks = <&clks 201>; is defined in
linux/include/dt-bindings/clock/imx6qdl-clock.h
also one can add cko2_podf, (it is defined in imx6qdl-clock.h as #define IMX6QDL_CLK_CKO2_PODF 199 )
and described in sect.18.6.21 CCM Clock Output Source Register (CCM_CCOSR) i.MX6Q RM
please check linux/arch/arm/mach-imx/clk-imx6q.c
http://git.freescale.com/git/cgit.cgi/imx/linux-2.6-imx.git/tree/arch/arm/mach-imx/clk-imx6q.c?h=imx...
imx_clk_set_parent(clk[IMX6QDL_CLK_CKO2_SEL], clk[IMX6QDL_CLK_OSC]);
imx_clk_set_parent(clk[IMX6QDL_CLK_CKO], clk[IMX6QDL_CLK_CKO2]);
Best regards
igor
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Hi igor,
Sorry , I not really clearly how to change that speed on ov5640_mipi? could you please explain more about that solution, where I should change the value of speed so that it can reduce frequency of mipi_ov5640. :smileyhappy: Thanks very much for your respond !
Best regards,
Dong
Hi Igor,
I tried to change clock from 201 to 199 like that clocks = <&clks 199> from device tree but camera can't work, there are no output for mclk also.
I don't know it's correct with your suggestion or not?
Thanks
Dong