/********************************************************************** *                I.MX6 KEY_ROW4 can't as GPIO pin * 说明： *     Tony遇到KEY_ROW4作为GPIO口时无法设置高、低电平问题，后来通过在 * 相关patch中找到方法，很特殊。 * *                                  2016-11-26 深圳 南山平山村 曾剑锋 *********************************************************************/一、参考文档：    1. android-imx6-kitkat/kernel_imx.git/3.0.35/SR-0013-Split-C1-to-C1-and-microsom.patch        https://github.com/rabeeh/android-imx6-kitkat/blob/master/kernel_imx.git/3.0.35/SR-0013-Split-C1-to-C1-and-microsom.patch    2. [meta-freescale] [PATCH] Added support for the SolidRun HummingBird    (also known as Carrier One)        https://lists.yoctoproject.org/pipermail/meta-freescale/2014-January/006271.html二、解决方法：    #define MX6DL_ENET_PAD_CTRL_PD (PAD_CTL_PKE | PAD_CTL_PUE  |        \            PAD_CTL_PUS_100K_DOWN | PAD_CTL_SPEED_MED |        \            PAD_CTL_DSE_40ohm   | PAD_CTL_HYS)    IOMUX_PAD(0x0650, 0x0268, 5, 0x0000, 0, MX6DL_ENET_PAD_CTRL_PD), /* KEY_ROW4 reset signal */