PWM

環境：Freescale imx6
            (共有4組pwm可以使用)

PWM (兩邊都要改)
1. bootable/bootloader/uboot-imx/board/freescale/mx6q_sabresd/mx6q_sabresd.c

imx_pwm_config(pwm0, 250000, 500000);
imx_pwm_enable(pwm0);

2. kernel_imx/arch/arm/mach-mx6/board-mx6q_sabresd.c

static struct platform_pwm_backlight_data mx6_sabresd_pwm_backlight_data = {
 .pwm_id = 0,
 .max_brightness = 248,
 .dft_brightness = 128,
 //.pwm_period_ns = 50000,
 .pwm_period_ns = 500000,
};