MCIMX6SL camera problem afte idling.

[satoshishimoda]

Hi community,

I have a problem on MCIMX6SLEVK.

Actually, MCIMX6SLEVK camera input does not works correctly after about 10 min from boot.

Please see the detail as below.

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[Board]

MCIMX6SLEVK

[BSP]

L3.0.35_4.1.0

[Condition]

1. A camera is connected to J24 connector on MCIMX6SLEVK.

2. Camera capture and I2C3 communication to the camera work continuously.

[Procedure]

1. Boot MCIMX6SLEVK with L3.0.35_4.1.0 BSP.

2. Leave MCIMX6SLEVK idle about 10 minutes.

[Problem]

After idling, sometime I2C3 SCL is pulled "low" and I2C communication does not work well.

Additionally, capturing from a camera which is connected to J24 and uses I2C3 does not work well.

(lack some frame, and jumble capture image)

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[Q]

Do you have a information about similar issue?

If you have it, could you tell me what should we modify?

If you need more information, please tell me it.

Best Regards,

Satoshi Shimoda

[satoshishimoda · Accepted solution]

Hi all,

I found the root cause.

It was caused by bus frequency scaling.

After about 10 min, set_low_bus_freq() and reduce_bus_freq_handler() function in /linux-3.0.35/arch/arm/mach-mx6/bus_freq.c is called.

Maybe, the reduced bus frequency is not sufficient to work camera and I2C.

We can avoid this issue by commenting out "reduce_bus_freq_handler()" or disable CONFIG_CPU_FREQ_GOV_POWERSAVE when building.

Best Regards,

Satoshi Shimoda