PWM frequency for LCD brightness in linux-3.10-at91

[merliness]

Hello,
I use the ARM AT91SAM9G35 with the linux-3.10-at91 and I would like to change the basic frequency of the LCD brightness. In this version of Linux, I think that , the backlight driver is not managed via the device tree. How do I change the base PWM
frequency and level of the backlight ?
In advance, thank you for your answer.
Best Regards,

[blue_z]

... I would like to change the basic frequency of the LCD brightness.

Since brightness does not have a frequency, what are you actually trying to accomplish?

In this version of Linux, I think that , the backlight driver is not managed via the device tree.

"Managed" is the wrong word; the Device Tree is for configuration.
The backlight is also not a descrete device, but composed of bits and pieces scattered about the board.

How do I change the base PWM frequency

You would have to hack the driver.

... and level of the backlight ?

Use the sysfs interface.

Regards